Police officers are a unique occupational group due to the fact that they have more health problems than many other occupations. These health problems could be a result of elevated inflammation markers caused by poor sleep. Sleep influences circadian rhythms, which thereby influences the function of the immune system. The immune system is responsible for the body’s inflammatory response using pro-inflammatory cytokines such as IL-6, CRP, Fibrinogen, and TNF-a. These cytokines can become elevated if disruption of the sleep cycle occurs. Elevated levels of inflammatory markers are associated with increased risk of cardiovascular disease. Police officers also work shifts and have a large amount of occupational stress that may contribute to increased levels of pro-inflammatory markers as well.
This analysis aimed to examine the influence that objective and subjective measures of sleep have on inflammatory markers among police officers within the Buffalo Cardio-Metabolic Occupational Police Stress (BCOPS) cohort crosssectionally. Body mass index (BMI), shift work, and stress measures were examined as potential effect modifiers. Subjective measures of sleep were obtained by the Pittsburgh Sleep Quality Index (PSQI) and objective measures of sleep were obtained through actigraph data. Police officers wore an Actiwatch for 15 consecutive days, where data was made into different sleep parameters.
Sleep latency, quality, duration, efficiency and daytime dysfunction were used from the PSQI, and wake after sleep onset, sleep onset latency, sleep duration, and efficiency were used from the actigraph measures. The inflammation markers were collected from blood samples after a 12 hour fast. Each inflammatory marker was measured using different assays at the University of Vermont.
General linear models were used to compare adjusted means of categorical sleep measures and beta coefficients for continuous sleep measures for each inflammation marker. Analyses were stratified by normal (18.5-24.9 BMI), overweight (25-29.9 BMI), and obese (≥30 BMI), and then by day and evening/night shiftwork. Logistic regression was performed on a dichotomous version of CRP, using a clinial cut point, and odds ratios were obtained for highrisk CRP. Statistically significant associations were seen between various sleep measures and inflammation markers. It is seen that as sleep worsens, there is an elevation in pro-inflammatory markers
