Conor S. O’Brien

Sleep Disorders, Health, and Safety in Police Officers

CONTEXT Sleep disorders often remain undiagnosed. Untreated sleep disorders among police officers may adversely affect their health and safety and pose a risk to the public. OBJECTIVE To quantify associations between sleep disorder risk and self-reported health, safety, and performance outcomes in police officers. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional and prospective cohort study of North American police officers participating in either an online or an on-site screening (n=4957) and monthly follow-up surveys (n=3545 officers representing 15,735 person-months) between July 2005 and December 2007. A total of 3693 officers in the United States and Canada participated in the online screening survey, and 1264 officers from a municipal police department and a state police department participated in the on-site survey. MAIN OUTCOME MEASURES Comorbid health conditions (cross-sectional); performance and safety outcomes (prospective). RESULTS Of the 4957 participants, 40.4% screened positive for at least 1 sleep disorder, most of whom had not been diagnosed previously. Of the total cohort, 1666 (33.6%) screened positive for obstructive sleep apnea, 281 (6.5%) for moderate to severe insomnia, 269 (5.4%) for shift work disorder (14.5% of those who worked the night shift). Of the 4608 participants who completed the sleepiness scale, 1312 (28.5%) reported excessive sleepiness. Of the total cohort, 1294 (26.1%) reported falling asleep while driving at least 1 time a month. Respondents who screened positive for obstructive sleep apnea or any sleep disorder had an increased prevalence of reported physical and mental health conditions, including diabetes, depression, and cardiovascular disease. An analysis of up to 2 years of monthly follow-up surveys showed that those respondents who screened positive for a sleep disorder vs those who did not had a higher rate of reporting that they had made a serious administrative error (17.9% vs 12.7%; adjusted odds ratio [OR], 1.43 [95% CI, 1.23-1.67]); of falling asleep while driving (14.4% vs 9.2%; adjusted OR, 1.51 [95% CI, 1.20-1.90]); of making an error or safety violation attributed to fatigue (23.7% vs 15.5%; adjusted OR, 1.63 [95% CI, 1.43-1.85]); and of exhibiting other adverse work-related outcomes including uncontrolled anger toward suspects (34.1% vs 28.5%; adjusted OR, 1.25 [95% CI, 1.09-1.43]), absenteeism (26.0% vs 20.9%; adjusted OR, 1.23 [95% CI, 1.08-1.40]), and falling asleep during meetings (14.1% vs 7.0%; adjusted OR, 1.95 [95% CI, 1.52-2.52]). CONCLUSION Among a group of North American police officers, sleep disorders were common and were significantly associated with increased risk of self-reported adverse health, performance, and safety outcomes.

High risk of near-crash driving events following night-shift work

Significance Drowsy driving is a major public health issue, particularly impacting the 9.5 million shift workers in America. Previous reports have assessed the impact of night work on driving in driving simulators. This real-vehicle driving study demonstrated increased objective and subjective drowsiness and degraded daytime driving performance in 16 night-shift workers while driving after a night of work, deteriorating with drive duration. No near-crashes occurred during driving after a night of sleep; 11 occurred during driving after night-work; all near-crashes occurred after at least 45 min of driving. Policy makers and night-workers should consider avoiding/minimizing driving or deploying effective countermeasures when driving after night-shift work to reduce drowsy driving and preventable crashes and injuries in this high-risk population. Night-shift workers are at high risk of drowsiness-related motor vehicle crashes as a result of circadian disruption and sleep restriction. However, the impact of actual night-shift work on measures of drowsiness and driving performance while operating a real motor vehicle remains unknown. Sixteen night-shift workers completed two 2-h daytime driving sessions on a closed driving track at the Liberty Mutual Research Institute for Safety: (i) a postsleep baseline driving session after an average of 7.6 ± 2.4 h sleep the previous night with no night-shift work, and (ii) a postnight-shift driving session following night-shift work. Physiological measures of drowsiness were collected, including infrared reflectance oculography, electroencephalography, and electrooculography. Driving performance measures included lane excursions, near-crash events, and drives terminated because of failure to maintain control of the vehicle. Eleven near-crashes occurred in 6 of 16 postnight-shift drives (37.5%), and 7 of 16 postnight-shift drives (43.8%) were terminated early for safety reasons, compared with zero near-crashes or early drive terminations during 16 postsleep drives (Fishers exact: P = 0.0088 and P = 0.0034, respectively). Participants had a significantly higher rate of lane excursions, average Johns Drowsiness Scale, blink duration, and number of slow eye movements during postnight-shift drives compared with postsleep drives (3.09/min vs. 1.49/min; 1.71 vs. 0.97; 125 ms vs. 100 ms; 35.8 vs. 19.1; respectively, P < 0.05 for all). Night-shift work increases driver drowsiness, degrading driving performance and increasing the risk of near-crash drive events. With more than 9.5 million Americans working overnight or rotating shifts and one-third of United States commutes exceeding 30 min, these results have implications for traffic and occupational safety.

Implementing a Sleep Health Education and Sleep Disorders Screening Program in Fire Departments: A Comparison of Methodology

Objective: The objective of this study is to compare three methods of administering a sleep health program (SHP) in fire departments. Methods: An SHP, comprising sleep health education and screening for common sleep disorders, was implemented in eight fire departments using three approaches: expert-led, train-the-trainer, and online. Participation rates, knowledge assessments, surveys, and focus group interviews were analyzed to assess the reach and effectiveness of the methodologies. Results: The Expert-led SHP had the highest participation rate, greatest improvement in knowledge scores, and prompted more firefighters to seek clinical sleep disorder evaluations (41%) than the other approaches (20 to 25%). Forty-two percent of focus group participants reported changing their sleep behaviors. Conclusion: All approaches yielded reasonable participation rates, but expert-led programs had the greatest reach and effectiveness in educating and screening firefighters for sleep disorders.

Prediction of drowsiness events in night shift workers during morning driving

The morning commute home is an especially vulnerable time for workers engaged in night shift work due to the heightened risk of experiencing drowsy driving. One strategy to manage this risk is to monitor the drivers state in real time using an in vehicle monitoring system and to alert drivers when they are becoming sleepy. The primary objective of this study is to build and evaluate predictive models for drowsiness events occurring in morning drives using a variety of physiological and performance data gathered under a real driving scenario. We used data collected from 16 night shift workers who drove an instrumented vehicle for approximately two hours on a test track on two occasions: after a night shift and after a night of rest. Drowsiness was defined by two outcome events: performance degradation (Lane-Crossing models) and electroencephalogram (EEG) characterized sleep episodes (Microsleep Models). For each outcome, we assessed the accuracy of sets of predictors, including or not including a driver factor, eyelid measures, and driving performance measures. We also compared the predictions using different time intervals relative to the events (e.g., 1-min prior to the event through 10-min prior). By examining the Area Under the receiver operating characteristic Curve (AUC), accuracy, sensitivity, and specificity of the predictive models, the results showed that the inclusion of an individual driver factor improved AUC and prediction accuracy for both outcomes. Eyelid measures improved the prediction for the Lane-Crossing models, but not for Microsleep models. Prediction performance was not changed by adding driving performance predictors or by increasing the time to the event for either outcome. The best models for both measures of drowsiness were those considering driver individual differences and eyelid measures, suggesting that these indicators should be strongly considered when predicting drowsiness events. The results of this paper can benefit the development of real-time drowsiness detection and help to manage drowsiness to avoid related motor-vehicle crashes and loss.

Sleep disorders, depression and anxiety are associated with adverse safety outcomes in healthcare workers: A prospective cohort study

The objective of the study was to determine if sleep disorder, depression or anxiety screening status was associated with safety outcomes in a diverse population of hospital workers. A sample of shift workers at four hospitals participated in a prospective cohort study. Participants were screened for five sleep disorders, depression and anxiety at baseline, then completed prospective monthly surveys for the next 6 months to capture motor vehicle crashes, near‐miss crashes, occupational exposures and medical errors. We tested the associations between sleep disorders, depression and anxiety and adverse safety outcomes using incidence rate ratios adjusted for potentially confounding factors in a multivariable negative binomial regression model. Of the 416 hospital workers who participated, two in five (40.9%) screened positive for a sleep disorder and 21.6% screened positive for depression or anxiety. After multivariable adjustment, screening positive for a sleep disorder was associated with 83% increased incidence of adverse safety outcomes. Screening positive for depression or anxiety increased the risk by 63%. Sleep disorders and mood disorders were independently associated with adverse outcomes and contributed additively to risk. Our findings suggest that screening for sleep disorders and mental health screening can help identify individuals who are vulnerable to adverse safety outcomes. Future research should evaluate sleep and mental health screening, evaluation and treatment programmes that may improve safety.

Cross-sectional analysis of sleep-promoting and wake-promoting drug use on health, fatigue-related error, and near-crashes in police officers

Objectives To examine sleep-promoting and wake-promoting drug use in police officers and associations between their use and health (excessive sleepiness, stress and burnout), performance (fatigue-related errors) and safety (near-crashes) outcomes, both alone and in combination with night-shift work. Design Cross-sectional survey. Setting Police officers from North America completed the survey either online or via paper/pencil at a police station. Participants 4957 police participated, 3693 online (91.9%, participation rate) and 1264 onsite (cooperation rate 63.1%). Main outcome measures Sleep-promoting and wake-promoting drug use, excessive sleepiness, near-crash motor vehicle crashes, dozing while driving, fatigue errors, stress and burnout. Results Over the past month, 20% of police officers reported using sleep-promoting drugs and drugs causing sleepiness, while wake-promoting agents were used by 28% of police (5% used wake-promoting drugs, 23% used high levels of caffeine and 4% smoked to stay awake). Use of sleep-promoting drugs was associated with increased near-crashes (OR=1.61; 95% CI 1.21 to 2.13), fatigue-related errors (OR=1.75; 95% CI 1.32 to 2.79), higher stress (OR=1.41; 95% CI 1.10 to 1.82), and higher burnout (OR=1.83; 95% CI 1.40 to 2.38). Wake-promoting drug use, high caffeine and smoking to stay awake were associated with increased odds of a fatigue-related error, stress and burnout (ORs ranging from 1.68 to 2.56). Caffeine consumption was common, and while smoking was not, of those participants who did smoke, one-in-three did so to remain awake. Night-shift work was associated with independent increases in excessive sleepiness, near-crashes and fatigue-related errors. Interactions between night-shift work and wake-promoting drug use were also found for excessive sleepiness. Conclusions Police who use sleep-promoting and wake-promoting drugs, especially when working night shifts, are most vulnerable to adverse health, performance and safety outcomes. Future research should examine temporal relationships between shift work, drug use and adverse outcomes, in order to develop optimal alertness management strategies.