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Blood pressure responses are dependent on call type and related to hypertension status in firefighters

Blood pressure responses are dependent on call type and related to hypertension status in... BLOOD PRESSURE 2023, VOL. 32, NO. 1, 2161997 https://doi.org/10.1080/08037051.2022.2161997 RESEARCH ARTICLE Blood pressure responses are dependent on call type and related to hypertension status in firefighters a b a c a,d Paige J. Rynne , Cassandra C. Derella , Carly McMorrow , Rachel L. Dickinson , Stephanie Donahue , a e f Andrew A. Almeida , Megan Carty and Deborah L. Feairheller a b Department of Kinesiology, University of New Hampshire, Durham, NH, USA; Department of Physiology, Augusta University, c d Augusta, GA, USA; Misericordia University, Pittsburgh, PA, USA; Philadelphia College of Osteopathic Medicine, Philadelphia, PA, e f USA; Jefferson College of Population Health, Thomas Jefferson University, Philadelphia, PA, USA; Department of Kinesiology, California State University San Marcos, San Marcos, CA, USA ABSTRACT ARTICLE HISTORY Received 31 October 2022 Background: Impaired cardiovascular health is a concern for firefighters, with over 50% of line- Revised 7 December 2022 of-duty deaths having cardiac causes. Many firefighters have hypertension and <25% have their Accepted 19 December 2022 blood pressure (BP) controlled. The alarm response could be an unidentified cardiac risk, but interestingly, the BP response to different calls and on-the-job activity is unknown. KEYWORDS Purpose: We aimed to measure the physiological stress resulting from different call types (fire, Ambulatory blood pressure; medical) and job activity (riding apparatus, pre-alert alarms) through ambulatory BP (ABP) moni- blood pressure surge; toring in a population of firefighters. cardiovascular disease; Materials and methods: During 111 12-h work shifts firefighters wore an ABP monitor. BP was firefighters; stress response; measured at 30-min intervals and manual measurements were prompted when the pager went hypertension; alarm response off or whenever they felt stress. Results: Firefighters were hypertensive (124.3 ± 9.9/78.1 ± 6.7 mmHg), overweight (30.2 ± 4.6 kg/m ), middle-aged (40.5 ± 12.6 years) and experienced (17.3 ± 11.7 years). We calculated an average 11% increase in systolic and 10.5% increase in diastolic BP with alarm. Systolic BP (141.9 ± 13.2 mmHg) and diastolic BP (84.9 ± 11.1 mmHg) and the BP surges were higher while firefighters were respond- ing to medical calls compared to fire calls. Between BP groups we found that medical call systolic BP (p¼ .001, d¼ 1.2), diastolic BP (p¼ .017, d¼ 0.87), and fire call systolic BP (p¼ .03, d¼ 0.51) levels were higher in the hypertensive firefighters. Conclusion: This is the first report of BP surge responses to alarms and to occupational activ- ities in firefighters, and medical calls elicited the largest overall responses. PLAIN LANGUAGE SUMMARY Cardiovascular disease and impaired cardiovascular health are substantially more prevalent in firefighters, with over 50% of line-of-duty deaths being cardiac related. Many firefighters are diagnosed with high blood pressure (hypertension), which is known to increase the risk of heart attacks, strokes, heart disease, and other serious health complications. Upon stress, our body enacts the ‘fight or flight’ response where sympathetic nervous system activity triggers an immediate increase in heart rate and blood pressure. This response can be dangerous when surges reach extreme levels due to underlying impaired cardiovascular function. It is known that alarm sounds trigger a stress response. Firefighters respond to different alarms while on the job, each indicating different call types, such as a house fire or a medical emergency. Due to the prevalence of impaired cardiovascu- lar health in firefighters, the physical stress resulting from these alerts is cause for concern. The blood pressure surge response to different call types and job activities in healthy and hypertensive firefighters had not been measured before this study. Through the ambulatory blood pressure monitoring of 111 on-duty firefighters, this study dis- covered that medical calls caused the greatest blood pressure and heart rate surge. Also, firefighters with hypertension experienced a greater blood pressure surge in response to alarms than their non-hypertensive co-workers. CONTACT Deborah L. Feairheller dfeairheller@csusm.edu Department of Kinesiology, California State University San Marcos, 333 S. Twin Oaks Valley Rd, San Marcos, CA 92096, USA 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 2 P. J. RYNNE ET AL. Introduction day-to-day basis due to their occupational demands [15,16]. Firefighting is an occupation characterised by Cardiovascular disease (CVD) continues to be a stress, exposure to harmful agents, hazardous health source of extreme health and economic burden. risks, pressure-filled situations, and immediate Cardiac-related incidents are critical issues in the response to alarms. It is known that an alarm sound military, in veterans, and in firefighters. It is known causes an instant sympathetic nervous system that CVD is the leading cause of mortality in the response where an immediate BP and heart rate spike world with many modifiable risk factors, including occurs, and it is thought that this could be a con- elevated blood pressure (BP), high total cholesterol, tributor to the line-of-duty death incidence in fire- smoking, diabetes, obesity, and physical inactivity [1]. fighters [16]. Based on the new guidelines for hypertension diagno- Anecdotal reports from firefighters and clinicians sis, a larger percentage of the population is identified include comments like ‘I know my BP spikes when as hypertensive [2]. Thus, the clinical use of ambula- the pager goes off’, and ‘I can feel my heart pound- tory BP (ABP) monitoring is becoming a valuable ing’. Therefore, we aimed to evaluate and quantify the tool for accurate diagnosis, management, and treat- physiological stress resulting from different types of ment of hypertension [2]. It is believed that ABP calls (fire, medical) and job activity (riding apparatus, measurements may better predict target organ damage pre-alert alarms in the firehouse) through ABP moni- from hypertension compared to brachial BP measured toring in a population of firefighters. Pre-alert systems in the office or clinic [3,4]. To better understand the are designed to alert firefighters of an incoming emer- aetiology of BP, studies are needed in a variety of gency dispatch call with the thought that a lighter or occupational groups, including tactical populations, softer sound would be less ‘stressful’, and these pre- that examine ABP responses to stimuli [5,6]. alert alarms are sounded in some firehouses. We Throughout the day, certain activities can trigger a hypothesised that fire calls would result in the largest stress response which temporarily elevates BP. This BP surge in firefighters compared to other types of response is known as a BP surge. Additionally, it is calls and work conditions. We also hypothesised that known that BP fluctuates, and a higher BP variability hypertensive firefighters would have exaggerated car- has prognostic value in predicting risk and future car- diovascular responses. diac events [7]. The lack of BP awareness and corres- pondingly high levels of hypertension remain public health issues. Current military studies have reported Materials and methods that CVD risk is on the rise in younger active and One hundred thirty-three firefighters were recruited reserve service members, and veterans still have worse from fire stations in the Philadelphia PA and Durham health profiles than their active-duty counterparts [8]. NH areas. From this, eight did not meet the BP meas- Also, CVD and impaired cardiovascular health are urement adherence threshold (70% during the 12-h noticeably more prevalent in firefighters than in civil- timeframe), four never had a 911 emergency call ians. In firefighters, over 50% of line-of-duty deaths occur, and 10 chose not to wear an ABP monitor for are cardiac-related [9]. Many firefighters have hyper- the full 12 h. Therefore, we present data on 111 tension, but <25% have their BP under control [10]. (100 M, 11 F) firefighters. This is a similar gender A recent study estimated that 39% of firefighters have ratio (9.9% female) to the overall firefighter popula- elevated levels of BP, 45% may fall in the Stage I and tion which has been reported by the National Stage II hypertensive categories, and 50% of fire- Firefighter Protection Agency (10% female) [17]. Any fighters do not know their BP [11]. We have previ- firefighters with history of diabetes or CVD were ously reported that firefighters have exaggerated BP excluded. During their first visit, each firefighter responses to a workload while wearing protective gear received a full explanation of the study protocol, com- [12], but no study has examined BP responses to the pleted a health history form, and provided written occupational activity. informed consent. The protocol was approved by the The increased CVD risk and higher levels of Ursinus College and the University of New hypertension seen in firefighters may be a combin- Hampshire Institutional Review Boards. ation of physical and emotional stress due to the Height and weight were measured using a stadiom- nature of the job. In prior studies, it has been shown that there is a direct relationship between work stress eter and digital floor scale (BC-533; Tanita and BP [13,14]. Firefighters and emergency service Corporation, Arlington Heights, IL, USA) without personnel have some of the most stressful jobs on a shoes. Body mass index (BMI) was calculated and BLOOD PRESSURE 3 recorded. Clinical BP measurements were collected in Data from firefighters who collected <70% of the accordance with guidelines following 5 min of rest. potential ABP readings during their 12-h work shift Multiple measurements were made several minutes were excluded. The number of potential ABP readings apart over at least 3 days, and the average of all read- was determined based on the 12-h timeframe when a ings is reported as clinical BP. firefighter wore the monitor, excluding any additional ABP monitoring was completed as previously readings that they may have been collected on the described [18]. Non-invasive portable ABP monitors job. The values of systolic and diastolic BP readings (SpaceLabs, Model 90127, Redmond, WA, USA) were were analysed separately. The distribution of all varia- worn by each firefighter for a 12-h period. BP meas- bles was examined using Shapiro–Wilk test of nor- ures were obtained at 30-min intervals during the mality. Differences between hypertensive and daytime period (6:00 a.m.–10:00 p.m.), and 60-min normotensive firefighters were evaluated using the intervals at night (10:00 p.m.–6:00 a.m.) if worn dur- independent sample t-test. Differences in BP readings ing that timeframe. Firefighters were all instructed to by occupational condition were assessed by one-way wear the monitor for at least 12 h. Some firefighters analysis of variance (ANOVA). The comparison of BP chose to wear the monitor for longer than 12 h so values within the group of firefighters between differ- that they could collect data for their own records, but ent call types or occupational activity were analysed we only analysed the data from their 12-h work shift. with paired t-test. Data was covaried for gender, age, When an emergency call came in and their pager and prior BP medication usage. The effect size for went off, firefighters were instructed to push the analysis was examined using Cohen’s d. Correlations monitor’s button to initiate an automatic BP reading. (Pearson, two-tailed) were calculated to examine rela- They were also asked to force BP readings when they tionships between BP measures. SPSS 28.0.1 (SPSS were riding the apparatus, when the pre-alert alarm Inc., Chicago, IL, USA) was used for all analyses. would sound in the firehouse, or at any other time that they felt ‘stress’ at work. These extra readings Results that were collected enabled our detailed analysis and were in addition to the normal 12-h ambulatory mon- Clinical characteristics are presented in Table 1. One itoring. We report here the data collected during fire hundred and eleven data points were included in the calls, medical calls, riding the apparatus, and pre-alert analysis which reports on 2930 total BP readings, alarm readings. Additionally, all firefighters enrolled with an average of 26.4 BP readings per 12-h shift. in the study were asked to keep a log while wearing During the 111 shifts, firefighters logged 186 total the ABP monitor. They were given a data sheet where calls that were captured by ABP monitoring. Data they self-reported information on the time of day for included is from 100 (90.1%) male firefighters and 11 each reading, what they were doing, how they were (9.9%) female firefighters. Firefighters reported an feeling, and what type of emergency call or work average of 17.3 years of service as a municipal fire- activity they were performing. The BP measurements fighter, with 56 (50.5%) reporting more than 15 years collected over the 12-h monitoring period were aver- of service. In all, 74 (66.7%) of the firefighters in our aged and the mean value is reported as ABP. The BP study were hypertensive according to clinical seated surge measurements collected upon alarm or under BP guidelines. Furthermore, 12 firefighters had stage stress were analysed in comparison to the immediate 2 hypertension, with a seated resting BP of BP reading taken at the time of the event. For com- 140 mmHg systolic or 90 mmHg diastolic. parison, the BP measurements collected for each con- Firefighters were informed of the clinical BP dition were averaged by group and are presented as apparatus BP, medical BP, fire call BP, and pre- Table 1. Firefighter characteristics. Entire group Normotensive FF Hypertensive FF alert BP. Age (years) 40.5 (12.6) 37.1 (13.7) 42.1 (11.9) # years as FF 17.3 (11.7) 16.1 (11.4) 17.9 (11.9) Height (cm) 175.0 (7.4) 172.6 (7.5) 176.2 (7.2) Statistical analysis Weight (kg) 91.3 (14.6) 82.1 (13.4) 95.8 (13.1) BMI (kgm ) 30.2 (4.6) 27.9 (4.1) 31.2 (4.3) The results are expressed as mean values ± standard # BP measures 26.4 (9.5) 25.8 (9.2) 26.7 (9.6) deviation, and significance was set at p< .05. For the FF: firefighter; BMI: body mass index; #BP measures: # blood pressure measurements collected. report of ABP measurements, all ABP readings were Data are presented as mean (SD) for 111 total firefighters; 37 normoten- averaged, for the 12-h period and for each condition, sive, 74 hypertensive. to give a single systolic and diastolic BP measure. Significant at p< .05 between groups. 4 P. J. RYNNE ET AL. Table 2. Blood pressure measurements. Entire group Normotensive FF Hypertensive FF Clinical SBP, mmHg 124.3 (9.9) 114.1 (4.9) 129.4 (7.6) Clinical DBP, mmHg 78.1 (6.7) 73.6 (5.3) 80.4 (6.1) Ambulatory SBP, mmHg 127.8 (12.1) 120.5 (9.4) 131.4 (11.7) Ambulatory DBP, mmHg 77.8 (8.5) 74.4 (7.1) 79.5 (8.7) Ambulatory MAP, mmHg 93.5 (9.2) 89.5 (7.5) 95.5 (9.5) 12 SBP surge, mmHg 17.1 (12.1) 14.8 (12.1) 18.2 (12.1) DBP surge, mmHg 10.3 (9.3) 8.4 (7.4) 11.2 (9.9) FF: firefighter; SBP: systolic; DBP: diastolic blood pressure; MAP: mean Fire Call Medical Call arterial pressure. Data are presented as mean (SD) for 111 total firefighters; 37 normoten- sive, 74 hypertensive. Significant at p< .05 between groups. measurements that were collected. If they were hyper- tensive, it was suggested that they follow-up with their clinician. Anecdotal reports from some of the participants were that they started to monitor their own BP levels while on shift, so the study raised awareness within the crews of the increased risk of Fire Call Medical Call hypertension. Between the hypertension groups, Figure 1. Blood pressure surge measured by call-type. Data height (p ¼ .02, d ¼ 0.49), weight (p ¼ .00, d ¼ 1.0), shows (A) systolic blood pressure (SBP) surge and (B) diastolic and BMI (p ¼ .00, d ¼ 0.76) were higher in the hyper- blood pressure (DBP) surge values in normotensive firefighters tensive firefighters. (solid bars) compared to hypertensive firefighters (open bars). BP surge values capture the BP immediately occurring when Blood pressure measurements are presented in the pager alarm sounds. p< .05 between groups. Table 2. Based on clinical guidelines, the entire group on average is classified as hypertensive which matches Table 3. Blood pressure by occupational condition. previous reports of hypertension in firefighters [2,10]. Entire group Normotensive FF Hypertensive FF Considering all of the BP measurements, we found an Apparatus SBP, mmHg 135.9 (12.2) 130.8 (13.9) 138.1 (10.9) average 11% increase in systolic and 10.5% increase in Apparatus DBP, mmHg 81.8 (10.2) 78.0 (8.5) 83.4 (10.6) diastolic BP with alarm, which corresponds to the cal- Medical call SBP, mmHg 141.9 (13.2) 131.0 (9.9) 145.6 (12.2) Medical call DBP, mmHg 84.9 (11.1) 78.1 (9.1) 87.2 (10.9) culated systolic BP surge of 17.1 mmHg and diastolic Fire call SBP, mmHg 138.4 (18.7) 132.6 (18.0) 141.8 (18.3) BP surge of 10.3 mmHg with the immediate measure- Fire call DBP, mmHg 83.7 (12.2) 80.5 (10.6) 85.6 (12.7) ment when pager sounds. Hypertensive firefighters Pre-alert SBP, mmHg 137.4 (10.5) 129.0 (6.9) 139.2 (10.4) Pre-alert DBP, mmHg 83.3 (8.2) 85.6 (9.1) 82.8 (8.2) seemed to have higher BP surge measurements than FF: firefighter; SBP: systolic blood pressure; DBP: diastolic blood pressure. normotensive firefighters, but this was not significant. Data are presented as mean (SD) for 111 total firefighters; 37 normoten- We found that clinical systolic (p ¼ 0.00, d ¼ 2.2) and sive, 74 hypertensive. Significant at p< .05 between groups. diastolic BP (p ¼ .00, d ¼ 1.1), average ambulatory sys- tolic (p ¼ .00, d ¼ 0.9) and diastolic BP (p ¼ .002, firefighters were able to collect different numbers of d ¼ 0.62), and ambulatory mean arterial pressure BP measurements. Table 3 reports the average values (p ¼ .001, d ¼ 0.67) were higher in the hypertensive from all readings collected while riding apparatus (10 firefighters. in normotensive and 23 measures collected in hyper- Figure 1 shows the comparison between hyperten- tensive firefighters), on a medical call (11 in normo- sive and normotensive firefighter responses to fire tensive and 33 measures collected in hypertensive and medical calls. Overall, medical calls appeared to firefighters), on a fire call (32 in normotensive and 54 elicit higher BP responses than fire calls. Between measures collected in hypertensive firefighters), and group analysis showed that systolic and diastolic BP with the pre-alert (three in normotensive and 14 surges were higher in hypertensive firefighters for measures collected in hypertensive firefighters). both fire and medical calls, with only the diastolic BP Within the entire group, we found that BP measured surge significantly higher between groups for fire calls in response to medical calls was the highest and BP (p ¼ .014, d ¼ 0.51). measured while firefighters rode apparatus was the BP measurements collected by the condition are presented in Table 3. The average blood pressure level lowest. In the group, systolic BP on a medical call measured was dependent on call or activity type. was higher than systolic BP (p ¼ .001, d ¼ 0.88) on the Based on the unpredictable nature of the job, apparatus, diastolic BP on a medical call was higher DBP Surge (mmHg) SBP Surge (mmHg) BLOOD PRESSURE 5 A purpose of this study was to quantify the physio- logical stress resulting from different types of calls (fire and medical) and job activity (riding apparatus and pre-alert alarms in the firehouse) through ABP monitoring in a population of firefighters. The main findings of this study are that the average BP level measured is dependent on call or activity type. We -10 90 110 130 150 170 190 hypothesised that fire calls would result in the largest -30 BP surge in firefighters compared to other types of 12-hour SBP Average (mmHg) calls and work conditions, but this was not true. We found that medical calls yielded the highest overall BP readings, and BP measured while firefighters rode apparatus was the lowest. We also hypothesised that hypertensive firefighters would have exaggerated responses, and this was confirmed. In our study, the hypertensive firefighters had higher BP levels and 10 appeared to have larger BP surges with alarm. Furthermore, it seems that high BP in any firefighter 50 60 70 80 90 100 110 has a direct relationship with the average ABP level. -10 Recently we summarised the literature on BP 12-hourDBP Average (mmHg) responses in firefighters and found that there is a gap Figure 2. Comparison of the relationship between (A) systolic in the literature examining BP response to alarm [19]. blood pressure (SBP) and (B) diastolic blood pressure (DBP) surge levels and 12-h ambulatory blood pressure averages. The tactical operations and hazardous nature of fire- Data shows the linear trend in hypertensive firefighters (Solid fighting influence the stress responses and therefore line, dark grey squares) and normotensive firefighters (dashed affect BP. Considering that hypertension in fire- line, light grey diamonds). BP surge values capture the BP fighters often remains undiagnosed or undocumented, immediately occurring when the pager alarm sounds. Both studies like this are valuable. Typically, the work of significant at p ¼ .01. firefighting, regardless of volunteer or career, involves than diastolic BP (p ¼ .02, d ¼ 0.54) taken on the long periods of inactivity followed by unpredictable apparatus, and systolic BP on a fire call was higher and sometimes physically demanding work, accompa- than the systolic BP (p ¼ .04, d ¼ 0.38) measured on nied by life-threatening activity. Evidence also sug- the apparatus. As shown in Table 3, between BP gests that such strenuous stimuli could result in groups we found that medical call systolic BP cardiac-related events [20]. It is known that alarm (p ¼ .001, d ¼ 1.2), diastolic BP (p ¼ .017, d ¼ 0.87), response, which is like the body’s fight-or-flight and fire call systolic BP (p ¼ .03, d ¼ 0.51) levels were response, is related to the risk of cardiac events higher in the hypertensive firefighters compared to around 10 times higher than the work of firefighting normotensive firefighters. [21]. Medical calls elicited the largest response from Figure 2 shows the correlation scatterplot figures for our firefighters, and future studies should examine both normotensive and hypertensive firefighters. We the psychosocial aspect of firefighting. As this is the found a stronger relationship in hypertensive fire- first report of BP surges, it needs to be examined why fighters (r ¼ .824, p ¼ .00) than in normotensive fire- medical calls had higher overall BP readings. Recent guidelines continue to advocate the use of fighters (r ¼ .29, p ¼ .11) between the systolic BP surge ABP monitoring for hypertension diagnosis [5,6]. BP in response to fire calls with the overall 12-h systolic measurements collected in the office provide a single ABP average. We also found a stronger relationship reading at one-time point of patient’s BP, so this one between 12-h diastolic ABP values and diastolic BP measurement may be less predictive of CVD risk. surge in hypertensive firefighters (r ¼ .529, p ¼ .00) Ambulatory monitoring allows assessment of daytime than in normotensive firefighters (r ¼ .19, p ¼ .29). BP, night-time BP, morning BP surge levels, and BP levels during daily or occupational activities. ABP Discussion may also be a clinical way to assess psychological This is the first report of measured BP surge values to stress [15]. Also, it has been suggested that the risk of 911 alarms in a group of municipal firefighters. The sudden cardiac death in firefighters may increase Fire Call DBP Surge (mmHg) Fire Call SBP Surge (mmHg) 6 P. J. RYNNE ET AL. 5–7 times during the alarm response compared to ratio of the American firefighting population (10% non-emergency time [21,22]. Prior research has found female) [17]. Firefighter attributes, such as alarm that higher anxiety and stress exist in firefighters fatigue, years of experience, hydration status, mental within the first minute of alarm exposure which may state, sleep status, and fitness level, were not taken continue throughout the extreme work of firefighting into consideration since this was the first data collec- [23]. The alarm sound activates the sympathetic ner- tion of this type. Previous studies have found that vous system which is also related to an increase in emergency alarms during the night elicit a larger HR sudden cardiac events during alarm responses [24]. In surge and cortisol response in comparison to alarms our firefighters, BP surge with medical calls was during the day [30]. In future studies, it would be higher for both systolic and diastolic BP levels. Prior beneficial to evaluate how these additional variables studies have found that firefighters with post-trau- affect the intensity of the cardiovascular response to matic stress disorder (PTSD) experience an increased different call types and job activities in firefighters. physiological stress response when exposed to a trau- In conclusion, the immediate increases in BP seen matic stimulus [25]. We speculate that the exagger- with alarm are a cause for concern given the impaired ated BP surge in response to medical calls is likely cardiovascular health of the average firefighter. due to the anticipation of traumatic events based on Specifically, firefighters who are clinically hypertensive past experiences, and the nature of medical calls. should be aware of their own BP levels, since it seems We saw that hypertensive firefighters seemed to that their BP levels during calls are exaggerated. experience higher BP surges. Hypertension remains Further research is needed to elucidate potential the leading risk factor for CVD with exaggerated physiological relationships with cardiac-related bio- morning BP surge in hypertensives having a strong markers and the BP response in firefighters to differ- relationship with CVD. It can be argued that BP ent call types and activities. Additionally, it would be alarm response to 911 pager tones in firefighters is beneficial to evaluate the effect of psychological fac- similar to an exaggerated BP surge, much like a tors, such as prior exposures to traumatic events, on morning BP surge [26]. Prospective research has dem- the cardiovascular response. Ascertaining how these onstrated that morning BP surge is a risk for cardiac factors impact the magnitude of the stress response is events, but it has yet to be determined whether the essential, as we hope this information will help iden- BP surge that emergency service personnel experience tify ways in which the BP surge in firefighters, and is related to CVD [27]. Furthermore, BP surge differ- the resulting risk of adverse cardiac events, can ences relate to BP variability and multiple definitions be reduced. exist for morning BP surge and BP variability. Prior research has found that higher morning BP surge is related to left ventricular mass and ejection fraction Acknowledgments ratios in older patients, while in firefighters it has The authors would like to thank the firefighters for partici- been reported that body composition is the only con- pating in our study. The authors would also like to thank sistently significant predictor of left ventricular mass the HEART lab student researchers who helped with indexes [28,29]. We are the first to report that fire- data collection. fighters with hypertension may have heightened responses to alarm. This should be investigated fur- Disclosure statement ther. The relationship between BP variability, BP No potential conflict of interest was reported by surge with alarm, and cardiac risk needs to be eval- the author(s). uated in future studies. A limitation of this research is that the study groups were in the Philadelphia PA and Durham NH Funding regions, both being suburban areas. Also, all fire- This work was supported by the American Heart fighters who participated were municipal firefighters. Association under Grant 19AIREA34450151 (Feairheller). Therefore, the data presented may not be representa- tive of firefighters in rural or urban areas or of the wildland urban-interface firefighters. The gender of Data availability statement participants in this study was unbalanced, with only The datasets generated and analysed during the current 11 of the 111 firefighters being female. However, this study are available from the corresponding author on rea- gender ratio (9.9% female) is aligned with the gender sonable request. BLOOD PRESSURE 7 [16] Rosenthal T, Alter A. Occupational stress and hyper- References tension. J Am Soc Hypertens. 2012;6(1):2–22. [1] Benjamin EJ, Blaha MJ, Chiuve SE, et al. Heart dis- [17] Haynes HJG, Stein P. US Fire Department Profile- ease and stroke statistics-2017 update: a report from 2015. NFPA Research; 2017. p. 1–47. the American Heart Association. Circulation. 2017; [18] Diaz KM, Veerabhadrappa P, Kashem MA, et al. 135(10):e146–e603. Relationship of visit-to-visit and ambulatory blood [2] Whelton PK, Carey RM, Aronow WS, et al. 2017 pressure variability to vascular function in African ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ Americans. Hypertens Res. 2012;35(1):55–61. ASPC/NMA/PCNA guideline for the prevention, [19] McMorrow C, Feairheller DL. Blood pressure detection, evaluation, and management of high responses in firefighters reviewed. Curr Hypertens blood pressure in adults: executive summary: a Rev. 2022;18(2):145–152. report of the American College of Cardiology/ [20] Mittleman MA, Maclure M, Tofler GH, et al. American Heart Association Task Force on clinical Triggering of acute myocardial infarction by heavy practice guidelines. J Am Coll Cardiol. 2018;71(19): physical exerction. Protection against triggering by 2199–2269. regular exertion. N Engl J Med. 1993;329(23): [3] Kikuya M, Ohkubo T, Asayama K, et al. 1677–1683. Ambulatory blood pressure and 10-year risk of car- [21] Kales SN, Soteriades ES, Christoudias SG, et al. diovascular and non-cardiovascular mortality: the Ohasama study. Hypertension. 2005;45(2):240–245. Firefighters and on-duty deaths from coronary heart [4] Verdecchia P. Prognostic value of ambulatory blood disease: a case control study. Environ Health. 2003; pressure: current evidence and clinical implications. 2(1):14. Hypertension. 2000;35(3):844–851. [22] Kales SN, Soteriades ES, Christophi CA, et al. [5] Dolan E, O’Brien E. How should ambulatory blood Emergency duties and deaths from heart disease pressure measurement be used in general practice? J among firefighters in the United States. N Engl J Clin Hypertens. 2017;19(3):218–220. Med. 2007;356(12):1207–1215. [6] O’Brien E, Parati G, Stergiou G. Ambulatory blood [23] Bugajska J, Zuzewicz K, Szmauz-Dybko M, et al. pressure measurement: what is the international Cardiovascular stress, energy expenditure and sub- consensus? Hypertension. 2013;62(6):988–994. jective perceived ratings of fire fighters during typ- [7] Blacher J, Safar ME, Ly C, et al. Blood pressure vari- ical fire suppression and rescue tasks. Int J Occup ability: cardiovascular risk integrator or independent Saf Ergon. 2007;13(3):323–331. risk factor? J Hum Hypertens. 2015;29(2):122–126. [24] Smith DL, DeBlois JP, Kales SN, et al. [8] Hoerster KD, Lehavot K, Simpson T, et al. Health Cardiovascular strain of firefighting and the risk of and health behavior differences US military, veteran, sudden cardiac events. Exerc Sport Sci Rev. 2016; and civilian men. Am J Prev Med. 2012;43(5): 44(3):90–97. 483–489. [25] Kales SN, Tsismenakis AJ, Zhang C, et al. Blood [9] Geibe JR, Holder J, Peeples L, et al. Predictors of pressure in firefighters, police officers, and other on-duty coronary events in male firefighters in the emergency responders. Am J Hypertens. 2009;22(1): United States. Am J Cardiol. 2008;101(5):585–589. [10] Soteriades ES, Kales SN, Liarokapis D, et al. 11–20. Prospective surveillance of hypertension in fire- [26] Bombelli M, Fodri D, Toso E, et al. Relationship fighters. J Clin Hypertens. 2003;5(5):315–320. among morning blood pressure surge, 24-hour [11] Risavi BL, Staszko J. Prevalence of risk factors for blood pressure variability, and cardiovascular out- coronary artery disease in Pennsylvania (USA) fire- comes in a white population. Hypertension. 2014; fighters. Prehosp Disaster Med. 2016;31(1):102–107. 64(5):943–950. [12] Feairheller DL. Blood pressure and heart rate [27] Kario K. Morning surge in blood pressure and car- responses in volunteer firefighters while wearing diovascular risk. Evidence and prespectives. personal protective equipment. Blood Press Monit. Hypertension. 2010;56(5):765–773. 2015;20(4):194–198. [28] Kuwajima I, Mitani K, Miyao M, et al. Cardiac [13] Andel SA, Pindek S, Spector PE. Being called to implications of the morning surge in blood pressure safety: occupational callings and safety climate in the in elderly hypertensive patients: relation to arising emergency medical services. J Occup Environ Med. time. Am J Hypertens. 1995;8(1):29–33. 2016;58(12):1245–1249. [29] Korre MS, Guilherme LGP, Farioli A, et al. Effect of [14] Vrijkotte TG, van Doornen LJ, de Geus EJ. Effects body mass index on left ventricular mass in career of work stress on ambulatory blood pressure, heart male firefighters. Am J Cardiol. 2016;118(11): rate, and heart rate variability. Hypertension. 2000; 1769–1773. 35(4):880–886. [30] Hall SJ, Aisbett B, Tait JL, et al. The acute physio- [15] Kaikkonen P, Lindholm H, Lusa S. Physiological logical stress response to an emergency alarm and load and psychological stress during a 24-hour work mobilization during the day and at night. Noise shift among Finnish firefighters. J Occup Environ Med. 2017;59(1):41–46. Health. 2016;18(82):150–156. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Blood Pressure Taylor & Francis

Blood pressure responses are dependent on call type and related to hypertension status in firefighters

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BLOOD PRESSURE 2023, VOL. 32, NO. 1, 2161997 https://doi.org/10.1080/08037051.2022.2161997 RESEARCH ARTICLE Blood pressure responses are dependent on call type and related to hypertension status in firefighters a b a c a,d Paige J. Rynne , Cassandra C. Derella , Carly McMorrow , Rachel L. Dickinson , Stephanie Donahue , a e f Andrew A. Almeida , Megan Carty and Deborah L. Feairheller a b Department of Kinesiology, University of New Hampshire, Durham, NH, USA; Department of Physiology, Augusta University, c d Augusta, GA, USA; Misericordia University, Pittsburgh, PA, USA; Philadelphia College of Osteopathic Medicine, Philadelphia, PA, e f USA; Jefferson College of Population Health, Thomas Jefferson University, Philadelphia, PA, USA; Department of Kinesiology, California State University San Marcos, San Marcos, CA, USA ABSTRACT ARTICLE HISTORY Received 31 October 2022 Background: Impaired cardiovascular health is a concern for firefighters, with over 50% of line- Revised 7 December 2022 of-duty deaths having cardiac causes. Many firefighters have hypertension and <25% have their Accepted 19 December 2022 blood pressure (BP) controlled. The alarm response could be an unidentified cardiac risk, but interestingly, the BP response to different calls and on-the-job activity is unknown. KEYWORDS Purpose: We aimed to measure the physiological stress resulting from different call types (fire, Ambulatory blood pressure; medical) and job activity (riding apparatus, pre-alert alarms) through ambulatory BP (ABP) moni- blood pressure surge; toring in a population of firefighters. cardiovascular disease; Materials and methods: During 111 12-h work shifts firefighters wore an ABP monitor. BP was firefighters; stress response; measured at 30-min intervals and manual measurements were prompted when the pager went hypertension; alarm response off or whenever they felt stress. Results: Firefighters were hypertensive (124.3 ± 9.9/78.1 ± 6.7 mmHg), overweight (30.2 ± 4.6 kg/m ), middle-aged (40.5 ± 12.6 years) and experienced (17.3 ± 11.7 years). We calculated an average 11% increase in systolic and 10.5% increase in diastolic BP with alarm. Systolic BP (141.9 ± 13.2 mmHg) and diastolic BP (84.9 ± 11.1 mmHg) and the BP surges were higher while firefighters were respond- ing to medical calls compared to fire calls. Between BP groups we found that medical call systolic BP (p¼ .001, d¼ 1.2), diastolic BP (p¼ .017, d¼ 0.87), and fire call systolic BP (p¼ .03, d¼ 0.51) levels were higher in the hypertensive firefighters. Conclusion: This is the first report of BP surge responses to alarms and to occupational activ- ities in firefighters, and medical calls elicited the largest overall responses. PLAIN LANGUAGE SUMMARY Cardiovascular disease and impaired cardiovascular health are substantially more prevalent in firefighters, with over 50% of line-of-duty deaths being cardiac related. Many firefighters are diagnosed with high blood pressure (hypertension), which is known to increase the risk of heart attacks, strokes, heart disease, and other serious health complications. Upon stress, our body enacts the ‘fight or flight’ response where sympathetic nervous system activity triggers an immediate increase in heart rate and blood pressure. This response can be dangerous when surges reach extreme levels due to underlying impaired cardiovascular function. It is known that alarm sounds trigger a stress response. Firefighters respond to different alarms while on the job, each indicating different call types, such as a house fire or a medical emergency. Due to the prevalence of impaired cardiovascu- lar health in firefighters, the physical stress resulting from these alerts is cause for concern. The blood pressure surge response to different call types and job activities in healthy and hypertensive firefighters had not been measured before this study. Through the ambulatory blood pressure monitoring of 111 on-duty firefighters, this study dis- covered that medical calls caused the greatest blood pressure and heart rate surge. Also, firefighters with hypertension experienced a greater blood pressure surge in response to alarms than their non-hypertensive co-workers. CONTACT Deborah L. Feairheller dfeairheller@csusm.edu Department of Kinesiology, California State University San Marcos, 333 S. Twin Oaks Valley Rd, San Marcos, CA 92096, USA 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 2 P. J. RYNNE ET AL. Introduction day-to-day basis due to their occupational demands [15,16]. Firefighting is an occupation characterised by Cardiovascular disease (CVD) continues to be a stress, exposure to harmful agents, hazardous health source of extreme health and economic burden. risks, pressure-filled situations, and immediate Cardiac-related incidents are critical issues in the response to alarms. It is known that an alarm sound military, in veterans, and in firefighters. It is known causes an instant sympathetic nervous system that CVD is the leading cause of mortality in the response where an immediate BP and heart rate spike world with many modifiable risk factors, including occurs, and it is thought that this could be a con- elevated blood pressure (BP), high total cholesterol, tributor to the line-of-duty death incidence in fire- smoking, diabetes, obesity, and physical inactivity [1]. fighters [16]. Based on the new guidelines for hypertension diagno- Anecdotal reports from firefighters and clinicians sis, a larger percentage of the population is identified include comments like ‘I know my BP spikes when as hypertensive [2]. Thus, the clinical use of ambula- the pager goes off’, and ‘I can feel my heart pound- tory BP (ABP) monitoring is becoming a valuable ing’. Therefore, we aimed to evaluate and quantify the tool for accurate diagnosis, management, and treat- physiological stress resulting from different types of ment of hypertension [2]. It is believed that ABP calls (fire, medical) and job activity (riding apparatus, measurements may better predict target organ damage pre-alert alarms in the firehouse) through ABP moni- from hypertension compared to brachial BP measured toring in a population of firefighters. Pre-alert systems in the office or clinic [3,4]. To better understand the are designed to alert firefighters of an incoming emer- aetiology of BP, studies are needed in a variety of gency dispatch call with the thought that a lighter or occupational groups, including tactical populations, softer sound would be less ‘stressful’, and these pre- that examine ABP responses to stimuli [5,6]. alert alarms are sounded in some firehouses. We Throughout the day, certain activities can trigger a hypothesised that fire calls would result in the largest stress response which temporarily elevates BP. This BP surge in firefighters compared to other types of response is known as a BP surge. Additionally, it is calls and work conditions. We also hypothesised that known that BP fluctuates, and a higher BP variability hypertensive firefighters would have exaggerated car- has prognostic value in predicting risk and future car- diovascular responses. diac events [7]. The lack of BP awareness and corres- pondingly high levels of hypertension remain public health issues. Current military studies have reported Materials and methods that CVD risk is on the rise in younger active and One hundred thirty-three firefighters were recruited reserve service members, and veterans still have worse from fire stations in the Philadelphia PA and Durham health profiles than their active-duty counterparts [8]. NH areas. From this, eight did not meet the BP meas- Also, CVD and impaired cardiovascular health are urement adherence threshold (70% during the 12-h noticeably more prevalent in firefighters than in civil- timeframe), four never had a 911 emergency call ians. In firefighters, over 50% of line-of-duty deaths occur, and 10 chose not to wear an ABP monitor for are cardiac-related [9]. Many firefighters have hyper- the full 12 h. Therefore, we present data on 111 tension, but <25% have their BP under control [10]. (100 M, 11 F) firefighters. This is a similar gender A recent study estimated that 39% of firefighters have ratio (9.9% female) to the overall firefighter popula- elevated levels of BP, 45% may fall in the Stage I and tion which has been reported by the National Stage II hypertensive categories, and 50% of fire- Firefighter Protection Agency (10% female) [17]. Any fighters do not know their BP [11]. We have previ- firefighters with history of diabetes or CVD were ously reported that firefighters have exaggerated BP excluded. During their first visit, each firefighter responses to a workload while wearing protective gear received a full explanation of the study protocol, com- [12], but no study has examined BP responses to the pleted a health history form, and provided written occupational activity. informed consent. The protocol was approved by the The increased CVD risk and higher levels of Ursinus College and the University of New hypertension seen in firefighters may be a combin- Hampshire Institutional Review Boards. ation of physical and emotional stress due to the Height and weight were measured using a stadiom- nature of the job. In prior studies, it has been shown that there is a direct relationship between work stress eter and digital floor scale (BC-533; Tanita and BP [13,14]. Firefighters and emergency service Corporation, Arlington Heights, IL, USA) without personnel have some of the most stressful jobs on a shoes. Body mass index (BMI) was calculated and BLOOD PRESSURE 3 recorded. Clinical BP measurements were collected in Data from firefighters who collected <70% of the accordance with guidelines following 5 min of rest. potential ABP readings during their 12-h work shift Multiple measurements were made several minutes were excluded. The number of potential ABP readings apart over at least 3 days, and the average of all read- was determined based on the 12-h timeframe when a ings is reported as clinical BP. firefighter wore the monitor, excluding any additional ABP monitoring was completed as previously readings that they may have been collected on the described [18]. Non-invasive portable ABP monitors job. The values of systolic and diastolic BP readings (SpaceLabs, Model 90127, Redmond, WA, USA) were were analysed separately. The distribution of all varia- worn by each firefighter for a 12-h period. BP meas- bles was examined using Shapiro–Wilk test of nor- ures were obtained at 30-min intervals during the mality. Differences between hypertensive and daytime period (6:00 a.m.–10:00 p.m.), and 60-min normotensive firefighters were evaluated using the intervals at night (10:00 p.m.–6:00 a.m.) if worn dur- independent sample t-test. Differences in BP readings ing that timeframe. Firefighters were all instructed to by occupational condition were assessed by one-way wear the monitor for at least 12 h. Some firefighters analysis of variance (ANOVA). The comparison of BP chose to wear the monitor for longer than 12 h so values within the group of firefighters between differ- that they could collect data for their own records, but ent call types or occupational activity were analysed we only analysed the data from their 12-h work shift. with paired t-test. Data was covaried for gender, age, When an emergency call came in and their pager and prior BP medication usage. The effect size for went off, firefighters were instructed to push the analysis was examined using Cohen’s d. Correlations monitor’s button to initiate an automatic BP reading. (Pearson, two-tailed) were calculated to examine rela- They were also asked to force BP readings when they tionships between BP measures. SPSS 28.0.1 (SPSS were riding the apparatus, when the pre-alert alarm Inc., Chicago, IL, USA) was used for all analyses. would sound in the firehouse, or at any other time that they felt ‘stress’ at work. These extra readings Results that were collected enabled our detailed analysis and were in addition to the normal 12-h ambulatory mon- Clinical characteristics are presented in Table 1. One itoring. We report here the data collected during fire hundred and eleven data points were included in the calls, medical calls, riding the apparatus, and pre-alert analysis which reports on 2930 total BP readings, alarm readings. Additionally, all firefighters enrolled with an average of 26.4 BP readings per 12-h shift. in the study were asked to keep a log while wearing During the 111 shifts, firefighters logged 186 total the ABP monitor. They were given a data sheet where calls that were captured by ABP monitoring. Data they self-reported information on the time of day for included is from 100 (90.1%) male firefighters and 11 each reading, what they were doing, how they were (9.9%) female firefighters. Firefighters reported an feeling, and what type of emergency call or work average of 17.3 years of service as a municipal fire- activity they were performing. The BP measurements fighter, with 56 (50.5%) reporting more than 15 years collected over the 12-h monitoring period were aver- of service. In all, 74 (66.7%) of the firefighters in our aged and the mean value is reported as ABP. The BP study were hypertensive according to clinical seated surge measurements collected upon alarm or under BP guidelines. Furthermore, 12 firefighters had stage stress were analysed in comparison to the immediate 2 hypertension, with a seated resting BP of BP reading taken at the time of the event. For com- 140 mmHg systolic or 90 mmHg diastolic. parison, the BP measurements collected for each con- Firefighters were informed of the clinical BP dition were averaged by group and are presented as apparatus BP, medical BP, fire call BP, and pre- Table 1. Firefighter characteristics. Entire group Normotensive FF Hypertensive FF alert BP. Age (years) 40.5 (12.6) 37.1 (13.7) 42.1 (11.9) # years as FF 17.3 (11.7) 16.1 (11.4) 17.9 (11.9) Height (cm) 175.0 (7.4) 172.6 (7.5) 176.2 (7.2) Statistical analysis Weight (kg) 91.3 (14.6) 82.1 (13.4) 95.8 (13.1) BMI (kgm ) 30.2 (4.6) 27.9 (4.1) 31.2 (4.3) The results are expressed as mean values ± standard # BP measures 26.4 (9.5) 25.8 (9.2) 26.7 (9.6) deviation, and significance was set at p< .05. For the FF: firefighter; BMI: body mass index; #BP measures: # blood pressure measurements collected. report of ABP measurements, all ABP readings were Data are presented as mean (SD) for 111 total firefighters; 37 normoten- averaged, for the 12-h period and for each condition, sive, 74 hypertensive. to give a single systolic and diastolic BP measure. Significant at p< .05 between groups. 4 P. J. RYNNE ET AL. Table 2. Blood pressure measurements. Entire group Normotensive FF Hypertensive FF Clinical SBP, mmHg 124.3 (9.9) 114.1 (4.9) 129.4 (7.6) Clinical DBP, mmHg 78.1 (6.7) 73.6 (5.3) 80.4 (6.1) Ambulatory SBP, mmHg 127.8 (12.1) 120.5 (9.4) 131.4 (11.7) Ambulatory DBP, mmHg 77.8 (8.5) 74.4 (7.1) 79.5 (8.7) Ambulatory MAP, mmHg 93.5 (9.2) 89.5 (7.5) 95.5 (9.5) 12 SBP surge, mmHg 17.1 (12.1) 14.8 (12.1) 18.2 (12.1) DBP surge, mmHg 10.3 (9.3) 8.4 (7.4) 11.2 (9.9) FF: firefighter; SBP: systolic; DBP: diastolic blood pressure; MAP: mean Fire Call Medical Call arterial pressure. Data are presented as mean (SD) for 111 total firefighters; 37 normoten- sive, 74 hypertensive. Significant at p< .05 between groups. measurements that were collected. If they were hyper- tensive, it was suggested that they follow-up with their clinician. Anecdotal reports from some of the participants were that they started to monitor their own BP levels while on shift, so the study raised awareness within the crews of the increased risk of Fire Call Medical Call hypertension. Between the hypertension groups, Figure 1. Blood pressure surge measured by call-type. Data height (p ¼ .02, d ¼ 0.49), weight (p ¼ .00, d ¼ 1.0), shows (A) systolic blood pressure (SBP) surge and (B) diastolic and BMI (p ¼ .00, d ¼ 0.76) were higher in the hyper- blood pressure (DBP) surge values in normotensive firefighters tensive firefighters. (solid bars) compared to hypertensive firefighters (open bars). BP surge values capture the BP immediately occurring when Blood pressure measurements are presented in the pager alarm sounds. p< .05 between groups. Table 2. Based on clinical guidelines, the entire group on average is classified as hypertensive which matches Table 3. Blood pressure by occupational condition. previous reports of hypertension in firefighters [2,10]. Entire group Normotensive FF Hypertensive FF Considering all of the BP measurements, we found an Apparatus SBP, mmHg 135.9 (12.2) 130.8 (13.9) 138.1 (10.9) average 11% increase in systolic and 10.5% increase in Apparatus DBP, mmHg 81.8 (10.2) 78.0 (8.5) 83.4 (10.6) diastolic BP with alarm, which corresponds to the cal- Medical call SBP, mmHg 141.9 (13.2) 131.0 (9.9) 145.6 (12.2) Medical call DBP, mmHg 84.9 (11.1) 78.1 (9.1) 87.2 (10.9) culated systolic BP surge of 17.1 mmHg and diastolic Fire call SBP, mmHg 138.4 (18.7) 132.6 (18.0) 141.8 (18.3) BP surge of 10.3 mmHg with the immediate measure- Fire call DBP, mmHg 83.7 (12.2) 80.5 (10.6) 85.6 (12.7) ment when pager sounds. Hypertensive firefighters Pre-alert SBP, mmHg 137.4 (10.5) 129.0 (6.9) 139.2 (10.4) Pre-alert DBP, mmHg 83.3 (8.2) 85.6 (9.1) 82.8 (8.2) seemed to have higher BP surge measurements than FF: firefighter; SBP: systolic blood pressure; DBP: diastolic blood pressure. normotensive firefighters, but this was not significant. Data are presented as mean (SD) for 111 total firefighters; 37 normoten- We found that clinical systolic (p ¼ 0.00, d ¼ 2.2) and sive, 74 hypertensive. Significant at p< .05 between groups. diastolic BP (p ¼ .00, d ¼ 1.1), average ambulatory sys- tolic (p ¼ .00, d ¼ 0.9) and diastolic BP (p ¼ .002, firefighters were able to collect different numbers of d ¼ 0.62), and ambulatory mean arterial pressure BP measurements. Table 3 reports the average values (p ¼ .001, d ¼ 0.67) were higher in the hypertensive from all readings collected while riding apparatus (10 firefighters. in normotensive and 23 measures collected in hyper- Figure 1 shows the comparison between hyperten- tensive firefighters), on a medical call (11 in normo- sive and normotensive firefighter responses to fire tensive and 33 measures collected in hypertensive and medical calls. Overall, medical calls appeared to firefighters), on a fire call (32 in normotensive and 54 elicit higher BP responses than fire calls. Between measures collected in hypertensive firefighters), and group analysis showed that systolic and diastolic BP with the pre-alert (three in normotensive and 14 surges were higher in hypertensive firefighters for measures collected in hypertensive firefighters). both fire and medical calls, with only the diastolic BP Within the entire group, we found that BP measured surge significantly higher between groups for fire calls in response to medical calls was the highest and BP (p ¼ .014, d ¼ 0.51). measured while firefighters rode apparatus was the BP measurements collected by the condition are presented in Table 3. The average blood pressure level lowest. In the group, systolic BP on a medical call measured was dependent on call or activity type. was higher than systolic BP (p ¼ .001, d ¼ 0.88) on the Based on the unpredictable nature of the job, apparatus, diastolic BP on a medical call was higher DBP Surge (mmHg) SBP Surge (mmHg) BLOOD PRESSURE 5 A purpose of this study was to quantify the physio- logical stress resulting from different types of calls (fire and medical) and job activity (riding apparatus and pre-alert alarms in the firehouse) through ABP monitoring in a population of firefighters. The main findings of this study are that the average BP level measured is dependent on call or activity type. We -10 90 110 130 150 170 190 hypothesised that fire calls would result in the largest -30 BP surge in firefighters compared to other types of 12-hour SBP Average (mmHg) calls and work conditions, but this was not true. We found that medical calls yielded the highest overall BP readings, and BP measured while firefighters rode apparatus was the lowest. We also hypothesised that hypertensive firefighters would have exaggerated responses, and this was confirmed. In our study, the hypertensive firefighters had higher BP levels and 10 appeared to have larger BP surges with alarm. Furthermore, it seems that high BP in any firefighter 50 60 70 80 90 100 110 has a direct relationship with the average ABP level. -10 Recently we summarised the literature on BP 12-hourDBP Average (mmHg) responses in firefighters and found that there is a gap Figure 2. Comparison of the relationship between (A) systolic in the literature examining BP response to alarm [19]. blood pressure (SBP) and (B) diastolic blood pressure (DBP) surge levels and 12-h ambulatory blood pressure averages. The tactical operations and hazardous nature of fire- Data shows the linear trend in hypertensive firefighters (Solid fighting influence the stress responses and therefore line, dark grey squares) and normotensive firefighters (dashed affect BP. Considering that hypertension in fire- line, light grey diamonds). BP surge values capture the BP fighters often remains undiagnosed or undocumented, immediately occurring when the pager alarm sounds. Both studies like this are valuable. Typically, the work of significant at p ¼ .01. firefighting, regardless of volunteer or career, involves than diastolic BP (p ¼ .02, d ¼ 0.54) taken on the long periods of inactivity followed by unpredictable apparatus, and systolic BP on a fire call was higher and sometimes physically demanding work, accompa- than the systolic BP (p ¼ .04, d ¼ 0.38) measured on nied by life-threatening activity. Evidence also sug- the apparatus. As shown in Table 3, between BP gests that such strenuous stimuli could result in groups we found that medical call systolic BP cardiac-related events [20]. It is known that alarm (p ¼ .001, d ¼ 1.2), diastolic BP (p ¼ .017, d ¼ 0.87), response, which is like the body’s fight-or-flight and fire call systolic BP (p ¼ .03, d ¼ 0.51) levels were response, is related to the risk of cardiac events higher in the hypertensive firefighters compared to around 10 times higher than the work of firefighting normotensive firefighters. [21]. Medical calls elicited the largest response from Figure 2 shows the correlation scatterplot figures for our firefighters, and future studies should examine both normotensive and hypertensive firefighters. We the psychosocial aspect of firefighting. As this is the found a stronger relationship in hypertensive fire- first report of BP surges, it needs to be examined why fighters (r ¼ .824, p ¼ .00) than in normotensive fire- medical calls had higher overall BP readings. Recent guidelines continue to advocate the use of fighters (r ¼ .29, p ¼ .11) between the systolic BP surge ABP monitoring for hypertension diagnosis [5,6]. BP in response to fire calls with the overall 12-h systolic measurements collected in the office provide a single ABP average. We also found a stronger relationship reading at one-time point of patient’s BP, so this one between 12-h diastolic ABP values and diastolic BP measurement may be less predictive of CVD risk. surge in hypertensive firefighters (r ¼ .529, p ¼ .00) Ambulatory monitoring allows assessment of daytime than in normotensive firefighters (r ¼ .19, p ¼ .29). BP, night-time BP, morning BP surge levels, and BP levels during daily or occupational activities. ABP Discussion may also be a clinical way to assess psychological This is the first report of measured BP surge values to stress [15]. Also, it has been suggested that the risk of 911 alarms in a group of municipal firefighters. The sudden cardiac death in firefighters may increase Fire Call DBP Surge (mmHg) Fire Call SBP Surge (mmHg) 6 P. J. RYNNE ET AL. 5–7 times during the alarm response compared to ratio of the American firefighting population (10% non-emergency time [21,22]. Prior research has found female) [17]. Firefighter attributes, such as alarm that higher anxiety and stress exist in firefighters fatigue, years of experience, hydration status, mental within the first minute of alarm exposure which may state, sleep status, and fitness level, were not taken continue throughout the extreme work of firefighting into consideration since this was the first data collec- [23]. The alarm sound activates the sympathetic ner- tion of this type. Previous studies have found that vous system which is also related to an increase in emergency alarms during the night elicit a larger HR sudden cardiac events during alarm responses [24]. In surge and cortisol response in comparison to alarms our firefighters, BP surge with medical calls was during the day [30]. In future studies, it would be higher for both systolic and diastolic BP levels. Prior beneficial to evaluate how these additional variables studies have found that firefighters with post-trau- affect the intensity of the cardiovascular response to matic stress disorder (PTSD) experience an increased different call types and job activities in firefighters. physiological stress response when exposed to a trau- In conclusion, the immediate increases in BP seen matic stimulus [25]. We speculate that the exagger- with alarm are a cause for concern given the impaired ated BP surge in response to medical calls is likely cardiovascular health of the average firefighter. due to the anticipation of traumatic events based on Specifically, firefighters who are clinically hypertensive past experiences, and the nature of medical calls. should be aware of their own BP levels, since it seems We saw that hypertensive firefighters seemed to that their BP levels during calls are exaggerated. experience higher BP surges. Hypertension remains Further research is needed to elucidate potential the leading risk factor for CVD with exaggerated physiological relationships with cardiac-related bio- morning BP surge in hypertensives having a strong markers and the BP response in firefighters to differ- relationship with CVD. It can be argued that BP ent call types and activities. Additionally, it would be alarm response to 911 pager tones in firefighters is beneficial to evaluate the effect of psychological fac- similar to an exaggerated BP surge, much like a tors, such as prior exposures to traumatic events, on morning BP surge [26]. Prospective research has dem- the cardiovascular response. Ascertaining how these onstrated that morning BP surge is a risk for cardiac factors impact the magnitude of the stress response is events, but it has yet to be determined whether the essential, as we hope this information will help iden- BP surge that emergency service personnel experience tify ways in which the BP surge in firefighters, and is related to CVD [27]. Furthermore, BP surge differ- the resulting risk of adverse cardiac events, can ences relate to BP variability and multiple definitions be reduced. exist for morning BP surge and BP variability. Prior research has found that higher morning BP surge is related to left ventricular mass and ejection fraction Acknowledgments ratios in older patients, while in firefighters it has The authors would like to thank the firefighters for partici- been reported that body composition is the only con- pating in our study. The authors would also like to thank sistently significant predictor of left ventricular mass the HEART lab student researchers who helped with indexes [28,29]. We are the first to report that fire- data collection. fighters with hypertension may have heightened responses to alarm. This should be investigated fur- Disclosure statement ther. The relationship between BP variability, BP No potential conflict of interest was reported by surge with alarm, and cardiac risk needs to be eval- the author(s). uated in future studies. A limitation of this research is that the study groups were in the Philadelphia PA and Durham NH Funding regions, both being suburban areas. Also, all fire- This work was supported by the American Heart fighters who participated were municipal firefighters. Association under Grant 19AIREA34450151 (Feairheller). Therefore, the data presented may not be representa- tive of firefighters in rural or urban areas or of the wildland urban-interface firefighters. The gender of Data availability statement participants in this study was unbalanced, with only The datasets generated and analysed during the current 11 of the 111 firefighters being female. However, this study are available from the corresponding author on rea- gender ratio (9.9% female) is aligned with the gender sonable request. BLOOD PRESSURE 7 [16] Rosenthal T, Alter A. Occupational stress and hyper- References tension. J Am Soc Hypertens. 2012;6(1):2–22. [1] Benjamin EJ, Blaha MJ, Chiuve SE, et al. Heart dis- [17] Haynes HJG, Stein P. US Fire Department Profile- ease and stroke statistics-2017 update: a report from 2015. NFPA Research; 2017. p. 1–47. the American Heart Association. Circulation. 2017; [18] Diaz KM, Veerabhadrappa P, Kashem MA, et al. 135(10):e146–e603. Relationship of visit-to-visit and ambulatory blood [2] Whelton PK, Carey RM, Aronow WS, et al. 2017 pressure variability to vascular function in African ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ Americans. Hypertens Res. 2012;35(1):55–61. ASPC/NMA/PCNA guideline for the prevention, [19] McMorrow C, Feairheller DL. Blood pressure detection, evaluation, and management of high responses in firefighters reviewed. Curr Hypertens blood pressure in adults: executive summary: a Rev. 2022;18(2):145–152. report of the American College of Cardiology/ [20] Mittleman MA, Maclure M, Tofler GH, et al. American Heart Association Task Force on clinical Triggering of acute myocardial infarction by heavy practice guidelines. J Am Coll Cardiol. 2018;71(19): physical exerction. Protection against triggering by 2199–2269. regular exertion. N Engl J Med. 1993;329(23): [3] Kikuya M, Ohkubo T, Asayama K, et al. 1677–1683. Ambulatory blood pressure and 10-year risk of car- [21] Kales SN, Soteriades ES, Christoudias SG, et al. diovascular and non-cardiovascular mortality: the Ohasama study. Hypertension. 2005;45(2):240–245. Firefighters and on-duty deaths from coronary heart [4] Verdecchia P. Prognostic value of ambulatory blood disease: a case control study. Environ Health. 2003; pressure: current evidence and clinical implications. 2(1):14. Hypertension. 2000;35(3):844–851. [22] Kales SN, Soteriades ES, Christophi CA, et al. [5] Dolan E, O’Brien E. How should ambulatory blood Emergency duties and deaths from heart disease pressure measurement be used in general practice? J among firefighters in the United States. N Engl J Clin Hypertens. 2017;19(3):218–220. Med. 2007;356(12):1207–1215. [6] O’Brien E, Parati G, Stergiou G. Ambulatory blood [23] Bugajska J, Zuzewicz K, Szmauz-Dybko M, et al. pressure measurement: what is the international Cardiovascular stress, energy expenditure and sub- consensus? Hypertension. 2013;62(6):988–994. jective perceived ratings of fire fighters during typ- [7] Blacher J, Safar ME, Ly C, et al. Blood pressure vari- ical fire suppression and rescue tasks. Int J Occup ability: cardiovascular risk integrator or independent Saf Ergon. 2007;13(3):323–331. risk factor? J Hum Hypertens. 2015;29(2):122–126. [24] Smith DL, DeBlois JP, Kales SN, et al. [8] Hoerster KD, Lehavot K, Simpson T, et al. Health Cardiovascular strain of firefighting and the risk of and health behavior differences US military, veteran, sudden cardiac events. Exerc Sport Sci Rev. 2016; and civilian men. Am J Prev Med. 2012;43(5): 44(3):90–97. 483–489. [25] Kales SN, Tsismenakis AJ, Zhang C, et al. Blood [9] Geibe JR, Holder J, Peeples L, et al. Predictors of pressure in firefighters, police officers, and other on-duty coronary events in male firefighters in the emergency responders. Am J Hypertens. 2009;22(1): United States. Am J Cardiol. 2008;101(5):585–589. [10] Soteriades ES, Kales SN, Liarokapis D, et al. 11–20. Prospective surveillance of hypertension in fire- [26] Bombelli M, Fodri D, Toso E, et al. Relationship fighters. J Clin Hypertens. 2003;5(5):315–320. among morning blood pressure surge, 24-hour [11] Risavi BL, Staszko J. Prevalence of risk factors for blood pressure variability, and cardiovascular out- coronary artery disease in Pennsylvania (USA) fire- comes in a white population. Hypertension. 2014; fighters. Prehosp Disaster Med. 2016;31(1):102–107. 64(5):943–950. [12] Feairheller DL. Blood pressure and heart rate [27] Kario K. Morning surge in blood pressure and car- responses in volunteer firefighters while wearing diovascular risk. Evidence and prespectives. personal protective equipment. Blood Press Monit. Hypertension. 2010;56(5):765–773. 2015;20(4):194–198. [28] Kuwajima I, Mitani K, Miyao M, et al. Cardiac [13] Andel SA, Pindek S, Spector PE. Being called to implications of the morning surge in blood pressure safety: occupational callings and safety climate in the in elderly hypertensive patients: relation to arising emergency medical services. J Occup Environ Med. time. Am J Hypertens. 1995;8(1):29–33. 2016;58(12):1245–1249. [29] Korre MS, Guilherme LGP, Farioli A, et al. Effect of [14] Vrijkotte TG, van Doornen LJ, de Geus EJ. Effects body mass index on left ventricular mass in career of work stress on ambulatory blood pressure, heart male firefighters. Am J Cardiol. 2016;118(11): rate, and heart rate variability. Hypertension. 2000; 1769–1773. 35(4):880–886. [30] Hall SJ, Aisbett B, Tait JL, et al. The acute physio- [15] Kaikkonen P, Lindholm H, Lusa S. Physiological logical stress response to an emergency alarm and load and psychological stress during a 24-hour work mobilization during the day and at night. Noise shift among Finnish firefighters. J Occup Environ Med. 2017;59(1):41–46. Health. 2016;18(82):150–156.

Journal

Blood Pressure – Taylor & Francis

Published: Jan 1, 2

Keywords: Ambulatory blood pressure; blood pressure surge; cardiovascular disease; firefighters; stress response; hypertension; alarm response

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