Khachatur Sarkisian

Long Work Hours and Adiposity Among Police Officers in a US Northeast City

Objective: To investigate the associations between long work hours and adiposity measures in police officers. Methods: Participants included 408 officers from the Buffalo Cardio-Metabolic Occupational Police Stress study who were examined between 2004 and 2009. Total work hours were abstracted from payroll records and questionnaires. Analysis of variance and covariance models were used. Results: Among male officers who worked the midnight shift, mean values of waist circumference and body mass index increased with longer work hours after adjustment for age, physical activity, energy intake, sleep duration, smoking status, police rank, activities after work (eg, child/family care, sports), and household income. Adiposity measures were not associated with work hours among women on any shift. Conclusion: Working longer hours was significantly associated with larger waist circumferences and higher body mass index among male police officers working the midnight shift.

A note on recovering the distributions from exponential moments

The problem of recovering a cumulative distribution function of a positive random variable via the scaled Laplace transform inversion is studied. The uniform upper bound of proposed approximation is derived. The approximation of a compound Poisson distribution as well as the estimation of a distribution function of the summands given the sample from a compound Poisson distribution are investigated. Applying the simulation study, the question of selecting the optimal scaling parameter of the proposed Laplace transform inversion is considered. The behavior of the approximants are demonstrated via plots and table.

Leptin, adiponectin, and heart rate variability among police officers

Police officers have a high prevalence of cardiovascular disease (CVD). Reduced heart rate variability (HRV) is known to increase CVD risk. Leptin and adiponectin may be related to CVD health. Therefore, our objective was to investigate the relationship between these variables and HRV.

Approximation of the ruin probability using the scaled Laplace transform inversion

The problem of recovering the ruin probability in the classical risk model based on the scaled Laplace transform inversion is studied. It is shown how to overcome the problem of evaluating the ruin probability at large values of an initial surplus process. Comparisons of proposed approximations with the ones based on the Laplace transform inversions using a fixed Talbot algorithm as well as on the ones using the Trefethen-Weideman-Schmelzer and maximum entropy methods are presented via a simulation study.

Associations between insulin and heart rate variability in police officers.

Low heart rate variability (HRV) has been linked to cardiovascular disease. Our objective was to examine the cross‐sectional association between insulin and HRV.

Effects of Ultraviolet Germicidal Irradiation (UVGI) on N95 Respirator Filtration Performance and Structural Integrity.

The ability to disinfect and reuse disposable N95 filtering facepiece respirators (FFRs) may be needed during a pandemic of an infectious respiratory disease such as influenza. Ultraviolet germicidal irradiation (UVGI) is one possible method for respirator disinfection. However, UV radiation degrades polymers, which presents the possibility that UVGI exposure could degrade the ability of a disposable respirator to protect the worker. To study this, we exposed both sides of material coupons and respirator straps from four models of N95 FFRs to UVGI doses from 120–950 J/cm2. We then tested the particle penetration, flow resistance, and bursting strengths of the individual respirator coupon layers, and the breaking strength of the respirator straps. We found that UVGI exposure led to a small increase in particle penetration (up to 1.25%) and had little effect on the flow resistance. UVGI exposure had a more pronounced effect on the strengths of the respirator materials. At the higher UVGI doses, the strength of the layers of respirator material was substantially reduced (in some cases, by >90%). The changes in the strengths of the respirator materials varied considerably among the different models of respirators. UVGI had less of an effect on the respirator straps; a dose of 2360 J/cm2 reduced the breaking strength of the straps by 20–51%. Our results suggest that UVGI could be used to effectively disinfect disposable respirators for reuse, but the maximum number of disinfection cycles will be limited by the respirator model and the UVGI dose required to inactivate the pathogen.

0065 Associations of Symptoms of Depression and Posttraumatic Stress Disorder with Peritraumatic Dissociation, and the role of Trauma Prior to Police Work

Objectives Our objective was to determine if symptoms of depression and posttraumatic stress disorder (PTSD) are associated with peritraumatic dissociation, and if this association is modified by trauma prior to police work. Method Symptoms of depression, PTSD symptoms, peritraumatic dissociative experience (PDE), and trauma before police work were measured using the Centre for Epidemiologic Studies Depression scale, PTSD Check List-Civilian Version, PDE questionnaire, and the brief trauma questionnaire, respectively in 328 police officers. Separate regression models were used to assess if either symptoms of depression or symptoms of PTSD were associated with PDE stratified by prior trauma. Means were adjusted for race, number of drinks per week, and smoking. Results PDE was significantly positively associated with symptoms of PTSD and depression (β = 0.642, p = 0.0001 and β = 0.276, p = 0.0002, respectively). PDE was positively associated with symptoms of PTSD regardless of trauma before police work (β = 0.599, p < 0.0001 (without prior trauma), 0.750, p < 0.0001 (with prior trauma). In contrast to PTSD, depression symptoms were significantly associated with PDE scores in individuals with prior trauma (β = 0.466, p = 0.0001), but not in individuals without prior trauma (β = 0.130, p = 0.155). Conclusions The results indicate that an increase in PDE is associated with an increase in symptoms of depression and PTSD. The results also show that PDE is associated with symptoms of PTSD regardless of prior trauma. In contrast, PDE was associated with depression symptoms only in individuals with prior trauma, indicating prior trauma may modify this relationship.

Association of Peritraumatic Dissociation With Symptoms of Depression and Posttraumatic Stress Disorder

Aim: In this study, we evaluated whether peritraumatic dissociation (PD) was associated with symptoms of depression and posttraumatic stress disorder (PTSD), and whether this association was modified by trauma prior to police work. Method: Symptoms of depression, PTSD, peritraumatic dissociative experience (PDE), and trauma prior to police work were measured using the Center for Epidemiologic Studies Depression scale, PTSD Checklist–Civilian, PDE questionnaire, and the Brief Trauma questionnaire, respectively, in 328 police officers. Separate regression models were used to assess if either symptoms of depression or PTSD were associated with PD stratified by prior trauma. Means were adjusted for race, number of drinks per week, and smoking. Results: PD was associated with symptoms of PTSD and depression (&bgr; = 0.65, p < .001 and &bgr; = 0.27, p < .001, respectively). PD was positively associated with symptoms of PTSD regardless of prior trauma (&bgr; = 0.61, p < .001(without prior trauma), 0.75, p < .001 (with prior trauma). In contrast to PTSD, depression symptoms were significantly associated with PD scores in individuals with prior trauma (&bgr; = 0.47, p < .001), but not in individuals without prior trauma (&bgr; = 0.13, p = .165). Limitations: This is a cross-sectional study. Outcomes were obtained via self-report and were not clinically diagnosed. Aspects of both the trauma event as well as the symptoms and severity of PD may have introduced recall bias. Conclusion: These results add to the literature indicating that PD plays a role in symptoms of PTSD and depression and how prior trauma may modify this relationship.

A Comparison of Two Laboratories for the Measurement of Wood Dust Using Button Sampler and Diffuse Reflection Infrared Fourier-Transform Spectroscopy (DRIFTS)

The current measurement method for occupational exposure to wood dust is by gravimetric analysis and is thus non-specific. In this work, diffuse reflection infrared Fourier transform spectroscopy (DRIFTS) for the analysis of only the wood component of dust was further evaluated by analysis of the same samples between two laboratories. Field samples were collected from six wood product factories using 25-mm glass fiber filters with the Button aerosol sampler. Gravimetric mass was determined in one laboratory by weighing the filters before and after aerosol collection. Diffuse reflection mid-infrared spectra were obtained from the wood dust on the filter which is placed on a motorized stage inside the spectrometer. The metric used for the DRIFTS analysis was the intensity of the carbonyl band in cellulose and hemicellulose at ~1735 cm(-1). Calibration curves were constructed separately in both laboratories using the same sets of prepared filters from the inhalable sampling fraction of red oak, southern yellow pine, and western red cedar in the range of 0.125-4 mg of wood dust. Using the same procedure in both laboratories to build the calibration curve and analyze the field samples, 62.3% of the samples measured within 25% of the average result with a mean difference between the laboratories of 18.5%. Some observations are included as to how the calibration and analysis can be improved. In particular, determining the wood type on each sample to allow matching to the most appropriate calibration increases the apparent proportion of wood dust in the sample and this likely provides more realistic DRIFTS results.

0052 Leptin, adiponectin, and heart rate variability among police officers

Objectives To investigate the relationship of leptin and adiponectin with heart rate variability (HRV). Method Leptin and adiponectin levels were measured in 388 non-diabetic officers from the Buffalo Cardio-Metabolic Occupational Police Stress study, following a 12-hour fast. HRV was performed according to methods published by the Task Force of the European Society of Cardiology and the North American Society of Pacing Electrophysiology for measurement and analysis of HRV. Mean values of high (HF) and low frequency (LF) HRV were compared across tertiles of leptin and adiponectin using ANOVA and ANCOVA; trends were assessed using linear regression models. Results Leptin, but not adiponectin, was significantly and inversely associated with HF and LF HRV. BMI and percent body fat (also waist circumference and abdominal height) significantly modified the association between leptin and LF (but not HF) HRV. Among officers with BMI <25 kg/m2, the association between leptin and HRV was not significant. However, among officers with BMI ≥25 kg/m2, the association between leptin and HRV was inversely related, after adjustment for age, gender, and race/ethnicity; p-values for trend (HF HRV, p = 0.019 and LF HRV, p < 0.0001). Similarly, among officers with percent body fat ≥25.5%, leptin and LF HRV showed significant, inverse associations (adjusted p for trend = 0.001). Conclusions Our results show that leptin levels were inversely and significantly associated with HRV among all officers, and particularly among officers with higher levels of adiposity. These results suggest that increased leptin levels may be associated with CVD-related health problems.