@article {bnh-5503, title = {Salivary cortisol profiles of on-call from home fire and emergency service personnel}, journal = {The International Journal on the Biology of Stress}, year = {2019}, month = {04/2019}, abstract = {

Working on-call with a night call resulted in a depressed (lower) cortisol awakening response (CAR) peak and post-awakening cortisol area under the curve with respect to ground (AUCG) the following day compared to when off-call. This may be due to exposure to noise, physical exertion, and stressful events during night callouts. There was no anticipatory effect to working on-call in any of the cortisol measures examined. This study, of male fire and emergency service workers who operate on-call from home, had two aims: (1) examine CAR and diurnal cortisol profile following a night on-call with a call, on-call without a call, and off-call; and, (2) explore whether there is an anticipatory effect of working on-call from home on diurnal cortisol profiles. Participants wore activity monitors, completed sleep and work diaries and collected seven saliva samples a day (0 min, 30 min, 60 min, 3 h, 6 h, 9 h, and 12 h after final awakening) for one week. CAR peak, reactivity and area under the curve with respect to increase (AUCI), post-awakening cortisol AUCG, diurnal cortisol slope and AUCG, and mean 12-h cortisol concentrations were calculated. The final analysis included 26 participants for Aim 1 (22 off-call nights, 68 nights on-call without a call, and 20 nights on-call with a call) and 14 participants for Aim 2 (25 days leading up to a night off-call and 92 days leading up to a night on-call). Generalized estimating equations models were constructed for each variable of interest. Aim 1: CAR peak and post-awakening cortisol AUCG\ were 8.2 {\textpm} 3.4 nmol/L and 5.7 {\textpm} 2.4 units lower, respectively, following a night on-call with a call compared to an off-call night. Aim 2: the day before a night on-call was not a significant predictor in any model. The lower CAR peak and post-awakening cortisol AUCG\ following a night on-call with a call compared to following an off-call night may be due to exposure to noise, physical exertion, and stressful events during night callouts. The lack of difference between the day before a night on-call and the day before an off-call night suggests there may not be an anticipatory effect on cortisol when on-call from home.

}, keywords = {Cortisol awakening response (CAR), distal on-call, diurnal cortisol profile, firefighters, home call, state emergency service workers}, doi = {https://doi.org/10.1080/10253890.2019.1584178}, url = {https://www.tandfonline.com/eprint/yDhRfifePuVq2Fxf8MCZ/full?target=10.1080\%2F10253890.2019.1584178\&}, author = {Sarah J Hall and Anne I. Turner and Sam J Robertson and Sally Ferguson and Brad Aisbett} } @article {bnh-4042, title = {The effect of working on-call from home on salivary cortisol in fire and emergency service personnel}, journal = {Psychoneuroendocrinology}, volume = {83}, year = {2017}, month = {11/2017}, abstract = {

On-call is an irregular work schedule allowing provision of 24-h services. Although it is purported that working on-call from home is stressful, little is known about impacts on stress physiology. This study aimed to (1) examine cortisol awakening response (CAR) and diurnal cortisol profile in fire and emergency service workers following a night on-call with a call (NIGHT), a night on-call without a call (NO) and an off-call night (OFF) and (2) explore whether there is an anticipatory effect of working on-call from home (ON) compared to off-call (OFF) on diurnal cortisol profiles.

}, doi = {10.1016/j.psyneuen.2017.07.289}, url = {http://www.psyneuen-journal.com/article/S0306-4530(17)30934-4/abstract}, author = {Sarah J Hall and Brad Aisbett and Sam J Robertson and Sally Ferguson and Anne I. Turner} } @article {bnh-3230, title = {Psychophysiological relationships between a multi-component self-report measure of mood, stress and behavioural signs and symptoms, and physiological stress responses during a simulated firefighting deployment}, journal = {International Journal of Psychophysiology}, volume = {110}, year = {2016}, month = {12/2016}, abstract = {

Physical work and sleep loss are wildland firefighting demands that elicit psychological and physiological stress responses. Research shows that these responses are statistically related which presents an opportunity to use subjective psychological questionnaires to monitor physiological changes among firefighters; an approach used extensively in sport settings. The aim of the present study was to investigate if changes in self-reported psychological factors on the multi-component training distress scale (MTDS), relate to cytokines and cortisol levels among firefighters completing three days of simulated physical firefighting work separated by an 8-h or restricted 4-h sleep each night. Each day firefighters completed the MTDS in the morning and salivary cortisol and inflammatory cytokines were measured throughout the day. When sleep restricted, firefighters demonstrated increases in MTDS factors of general fatigue, perceived stress and depressed mood that were related to elevated cytokines (TNF-α, IL-8, IL-10, IL-6) and cortisol. Conversely, firefighters who had an 8-h sleep demonstrated a positive relationship between physical signs and symptoms and elevated IL-6, while depressed mood was inversely related to decreasing cortisol and cytokines (IL-6, TNF-α, IL-10). Findings highlight the utility of the MTDS to detect psychological changes that reflect physiological responses among firefighters. Future research that establishes thresholds for specific factors which predict health-related physiological changes, will allow fire agencies implement multi-component measures to monitor and manage the health of personnel on the fire-ground.

}, doi = {http://dx.doi.org/10.1016/j.ijpsycho.2016.10.015}, url = {http://www.sciencedirect.com/science/article/pii/S0167876016307681}, author = {Alexander Wolkow and Brad Aisbett and Sally Ferguson and John Reynolds and Luana Main} } @article {bnh-2503, title = {The sleep architecture of Australian volunteer firefighters during a multi-day simulated wildfire suppression: Impact of sleep restriction and temperature}, journal = {Accident Analysis \& Prevention}, year = {2015}, month = {11/2015}, abstract = {

Author(s): Michael A. Cvirn, Jillian Dorrian, Bradley P. Smith, Sarah M. Jay, Grace E. Vincent, Sally A. Ferguson

Wildland firefighting exposes personnel to combinations of occupational and environmental stressors that include physical activity, heat and sleep restriction. However, the effects of these stressors on sleep have rarely been studied in the laboratory, and direct comparisons to field scenarios remain problematic. The aim of this study was to examine firefighters{\textquoteright} sleep during a three-day, four-night simulated wildfire suppression that included sleep restriction and physical activity circuits representative of firefighting wildfire suppression tasks in varied temperatures. Sixty-one volunteer firefighters (37.5{\textpm}14.5 years of age, mean{\textpm}SD) were assigned to one of three conditions: control (n =25; 8h sleep opportunities and 18{\textendash}20{\textdegree}C), awake (n =25; 4h sleep opportunities and 18{\textendash}20{\textdegree}C) or awake/hot (n =11; 4h sleep opportunities and 33{\textendash}35{\textdegree}C during the day and 23{\textendash}25{\textdegree}C during the night). Results demonstrated that amounts of N1, N2 and R sleep, TST, SOL and WASO declined, whilst sleep efficiency increased significantly in the awake and awake/hot conditions compared to the control condition. Results also demonstrated that SWS sleep remained relatively stable in the awake and awake/hot conditions compared to control values. Most importantly, no significant differences were found for any of the sleep measures between the awake and awake/hot conditions. Thus, working in hot daytime temperatures in combination with sleep restriction during the night did not affect patterns of sleep compared to working in temperate conditions in combination with sleep restriction during the night. However, the effects on sleep of high (\>25{\textdegree}C) night-time temperatures with sleep restriction in addition to physical activity remains to be studied.

}, url = {http://www.sciencedirect.com/science/article/pii/S0001457515301287}, author = {Michael A Cvirn and Jillian Dorrian and Bradley P Smith and Sarah M Jay and Sally Ferguson}, editor = {Grace Vincent} } @article {bnh-1736, title = {Sleep Restriction during Simulated Wildfire Suppression: Effect on Physical Task Performance}, journal = {PLOS ONE}, volume = {10}, year = {2015}, month = {01/2015}, abstract = {

Objectives

To examine the effects of sleep restriction on firefighters{\textquoteright} physical task performance during simulated wildfire suppression.

Methods

Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18) or a sleep restricted condition (4-hour sleep opportunity, n = 17). Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods.

Results

There were no differences between the sleep-restricted and control groups in firefighters{\textquoteright} task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group.

Conclusions

Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters{\textquoteright} performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters{\textquoteright} operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

}, keywords = {Firefighter fatigue, simulated wildfire suppression, sleep deprivation}, doi = {10.1371/journal.pone.0115329}, url = {http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0115329}, author = {Grace Vincent and Sally Ferguson and Jacqueline Tran and Larsen, Brianna and Alexander Wolkow and Brad Aisbett} } @article {bnh-1836, title = {Sleeping at work: not all about location, location, location}, journal = {Sleep Medicine Reviews}, volume = {19}, year = {2014}, month = {05/2014}, pages = {59-66}, chapter = {59}, abstract = {

Working arrangements in industries that use non-standard hours sometimes necessitate an {\textquoteleft}onsite{\textquoteright} workforce where workers sleep in accommodation within or adjacent to the workplace. Of particular relevance to these workers is the widely held (and largely anecdotal) assumption that sleep at home is better than sleep away, particularly when away for work. This narrative review explores the idea that sleep outcomes in these unique work situations are the product of an interaction between numerous factors including timing and duration of breaks, commute length, sleeping environment (noise, movement, vibration, light), circadian phase, demographic factors and familiarity with the sleep location. Based on the data presented in this review, it is our contention that the location of sleep, whilst important, is secondary to other factors such as the timing and duration of sleep periods. We suggest that future research should include measures that allow conceptualisation of other critical factors such as familiarity with the sleeping environment.

}, keywords = {Mobile workplaces, Non-residential workforce, Shift work, Sleep, Sleep environment, Sleep loss, Work rest facilities}, doi = {http://dx.doi.org/10.1016/j.smrv.2014.04.003}, url = {http://www.smrv-journal.com/article/S1087-0792(14)00044-6/abstract}, author = {Sarah M Jay and Brad Aisbett and Sprajcer, M. and Sally Ferguson} }