Faculty Bibliography

BACKGROUND: The hypothalamic-pituitary-adrenal axis is a major stress response system hypothesized to be involved in the pathogenesis of posttraumatic stress disorder (PTSD). However, few studies have prospectively examined the relationships among pre-exposure hypothalamic-pituitary-adrenal activity, acute stress reactions and PTSD. METHODS: Two hundred ninety-six police recruits were assessed during academy training before critical incident exposure and provided salivary cortisol at first awakening and after 30 minutes. A measure of cortisol awakening response (CAR) was computed as the change in cortisol level from the first to the second collection. At 12, 24, and 36 months following the start of active police service, officers were assessed for peritraumatic distress, peritraumatic dissociation, acute stress disorder (ASD) symptoms, and PTSD symptoms to their self-identified worst duty-related critical incident. Mixed models for repeated measures were used to analyze the effects of CAR on the outcome variables pooled across the three follow-up assessments. RESULTS: After controlling for time of awakening, first awakening cortisol levels, and cumulative critical incident stress exposure, CAR during academy training was associated with greater peritraumatic dissociation, beta = .14, z = 3.49, p < .0001, and greater ASD symptoms during police service assessed at 12, 24, and 36 months, beta = .09, Z = 2.03, p < .05, but not with peritraumatic distress, beta = .03, z = .81, p = .42, or PTSD symptoms, beta = -.004, z = -.09, p = .93. CONCLUSIONS: These findings suggest that greater cortisol response to awakening is a pre-exposure risk factor for peritraumatic dissociation and ASD symptoms during police service

BACKGROUND: Exposure to traumatic events is a necessary but not a sufficient condition for the development of posttraumatic stress disorder (PTSD). Pretrauma, peritrauma and posttrauma factors interact to impact on symptom severity. The aim of the present study is to determine risk factors for PTSD symptoms in Brazilian police officers. METHOD: In a cross-sectional sample of active duty officers (n = 212), participants were asked to complete a socio-demographic questionnaire and self-report scales on affective traits, cumulative critical incident exposure, peritraumatic distress and dissociation, PTSD symptoms, and social support. Hierarchical linear regression analysis was conducted to examine predictors of PTSD symptoms. RESULTS: Variables related to negative affect, job duration, frequency of critical incident exposure, peritraumatic dissociation, and lack of social support remained significant in the final model and explained 55% of the variance in PTSD symptoms. When interaction terms were evaluated, a synergistic effect between negative affect and peritraumatic dissociation was found. CONCLUSIONS: The risk factors found in this study provide clues on how to elaborate primary prevention strategies regarding PTSD symptoms in police officers. Such initiatives may lessen the impact of repeated exposure to traumatic events on police officers over the course of their careers.

Research has consistently demonstrated that stress reactions to potentially traumatic events do not represent a unified phenomenon. Instead, individuals tend to cluster into prototypical response patterns over time including chronic symptoms, recovery, and resilience. We examined heterogeneity in a posttraumatic stress disorder (PTSD) symptom course in a sample of 178 active-duty police officers following exposure to a life-threatening event using latent growth mixture modeling (LGMM). This analysis revealed 3 discrete PTSD symptom trajectories: resilient (88%), distressed-improving (10%), and distressed-worsening (2%). We further examined whether trait and peritraumatic dissociation distinguished these symptom trajectories. Findings indicate that trait and peritraumatic dissociation differentiated the resilient from the distressed-improving trajectory (trait, p < .05; peritraumatic, p < .001), but only peritraumatic dissociation differentiated the resilient from the distressed-worsening trajectory (p < .001). It is essential to explore heterogeneity in symptom course and its predictors among active-duty police officers, a repeatedly exposed group. These findings suggest that police officers may be a highly resilient group overall. Furthermore, though there is abundant evidence that dissociation has a positive linear relationship with PTSD symptoms, this study demonstrates that degree of dissociation can distinguish between resilient and symptomatic groups of individuals

This study examined the relationship between killing or seriously injuring someone in the line of duty and mental health symptoms in a sample of police officers (N = 400) who were first assessed during academy training and at five additional time points over three years. We found that nearly 10% of police officers reported having to kill or seriously injure someone in the line of duty in the first three years of police service. After controlling for demographics and exposure to life threat, killing or seriously injuring someone in the line of duty was significantly associated with PTSD symptoms (p < .01) and marginally associated with depression symptoms (p = .06). These results highlight the potential mental health impact of killing or seriously injuring someone in the line of duty. Greater attention to mental health services following these types of exposures can serve as a preventative measure for police officers who have been negatively impacted

Although police officers are frequently exposed to potentially traumatic incidents, only a minority will develop chronic posttraumatic stress disorder (PTSD). Identifying and understanding protective factors could inform the development of preventive interventions; however, few studies have examined this. In the present prospective study, 233 police officers were assessed during academy training and again following 2 years of police service. Caucasian race, less previous trauma exposure, and less critical incident exposure during police service as well as greater sense of self-worth, beliefs of greater benevolence of the world, greater social support and better social adjustment, all assessed during academy training, were associated with lower PTSD symptoms after 2 years of service. Positive personality attributes assessed during training with the NEO Five-Factor Personality Inventory were not associated with lower PTSD symptoms. In a hierarchical linear regression model, only Caucasian race, lower critical incident exposure during police service, greater assumptions of benevolence of the world and better social adjustment during training remained predictive of lower PTSD symptoms after 2 years of police service. These results suggest that positive world assumptions and better social functioning during training may protect police officers from critical incident related PTSD

Post-traumatic stress disorder (PTSD) is associated with elevated catecholamines and increased sympathetic arousal. However, it is unknown whether this condition is a pre-existing vulnerability factor for PTSD or an acquired result of either trauma exposure or the development of PTSD symptoms. We sought to examine if salivary 3-methoxy-4-hydroxy-phenylglycol (MHPG) in response to a laboratory stressor prior to critical incident exposure predicts the development of PTSD symptoms and if early childhood trauma influences this relationship. In a prospective cohort study, 349 urban police officers were assessed during academy training (baseline) and 243 were reassessed 12 months after the start of active duty (follow-up). At baseline, participants observed a video consisting of police critical incidents. Salivary MHPG was measured before and immediately after the challenge, and after 20min recovery. At follow-up, peritraumatic distress and PTSD symptoms were assessed in relationship to the worst critical incident during the past year. Participants with childhood trauma showed a trend towards higher MHPG increase to the challenge. Higher MHPG levels after 20min recovery were associated with both higher levels of peritraumatic distress and PTSD symptoms at follow-up. In a path analysis, elevated MHPG levels predicted higher peritraumatic distress which in turn predicted higher levels of PTSD symptoms while the direct effect of elevated MHPG levels on PTSD symptoms was no longer significant. Prolonged elevation of salivary MHPG in response to a laboratory stressor marks a predisposition to experience higher levels of peritraumatic distress and subsequently more PTSD symptoms following critical incident exposure

Aviation, military, police, and health care personnel have been particularly interested in the operational impact of sleep restriction and work schedules given the potential severe consequences of making fatigue-related errors. Most studies examining the impact of sleep loss or circadian manipulations have been conducted in controlled laboratory settings using small sample sizes. This study examined whether the relationship between prior night sleep duration and performance on the psychomotor vigilance task could be reliably detected in a field study of healthy police academy recruits. Subjects (N = 189) were medically and psychiatrically healthy. Sleep-wake activity was assessed with wrist actigraphy for 7 days. Subjects performed the psychomotor vigilance task (PVT) for 5 min on a personal digital assistant (PDA) device before and after their police academy workday and on comparable times during their days off. Mixed-effects logistic regression was used to estimate the probability of having > or =1 lapse on the PVT as a function of the previous night sleep duration during the 7 days of field testing. Valid estimates of sleep duration were obtained for 1082 nights of sleep. The probability of a lapse decreased by 3.5%/h sleep the night prior to testing. The overall probability of having a lapse decreased by 0.9%/h since awakening, holding hours of sleep constant. Perceived stress was not associated with sleep duration or probability of performance lapse. These findings demonstrate the feasibility of detecting sleep and circadian effects on cognitive performance in large field studies. These findings have implications regarding the daytime functioning of police officers

Police work is one of the most stressful occupations. Previous research has indicated that work stress and trauma exposure may place individuals at heightened risk for the development of depression symptomatology. This prospective longitudinal study was designed to examine predictors of depression symptoms in police service. Participants comprised 119 healthy police recruits from an ongoing prospective study. They completed baseline measures of depression symptoms, childhood trauma exposure, neuroticism, and self-worth during academy training. Follow-up measures of depression symptoms, PTSD symptoms, critical incident exposure, negative life events, and routine work environment stress were assessed after 12 months of police service. Hierarchical linear regression analysis was conducted to examine predictors of current levels of depression symptoms, controlling for baseline depression symptoms and current PTSD symptoms. Greater childhood trauma exposure, lower self-worth during training, and greater perceived work stress in the first year of police service predicted greater depression symptoms at 12 months. Depression symptoms at 1 year of police service were partly independent from PTSD symptoms at 12 months. Greater childhood trauma exposure and lower self-worth during training may be important variables to screen as risk factors for duty-related depression. Strategies to reduce routine work environment stress have the potential to decrease duty-related depression in law enforcement

BACKGROUND: Family history of psychiatric and substance use disorders has been associated with posttraumatic stress disorder (PTSD) in cross-sectional studies. METHOD: Using a prospective design, we examined the relationships of family history of psychiatric and substance use disorders to posttraumatic stress symptoms in 278 healthy police recruits. During academy training, recruits were interviewed on family and personal psychopathology, prior cumulative civilian trauma exposure, and completed self-report questionnaires on nonspecific symptoms of distress and alcohol use. Twelve months after commencement of active duty, participants completed questionnaires on critical incident exposure over the previous year, peritraumatic distress to the worst critical incident during this time, and posttraumatic stress symptoms. RESULTS: A path model indicated: (1) family loading for mood and anxiety disorders had an indirect effect on posttraumatic stress symptoms at 12 months that was mediated through peritraumatic distress to the officer's self-identified worst critical incident, (2) family loading for substance use disorders also predicted posttraumatic stress symptoms at 12 months and this relationship was mediated through peritraumatic distress. CONCLUSION: These findings support a model in which family histories of psychopathology and substance abuse are pre-existing vulnerability factors for experiencing greater peritraumatic distress to critical incident exposure which, in turn, increases the risk for development of symptoms of posttraumatic stress disorder. Replication in other first responders, military and civilians will be important to determine generalizability of these findings

This study examined the relationship between routine work environment stress and posttraumatic stress disorder (PTSD) symptoms in a sample of police officers (N = 180) who were first assessed during academy training and reassessed 1-year later. In a model that included gender, ethnicity, traumatic exposure prior to entering the academy, current negative life events, and critical incident exposure over the last year, routine work environment stress was most strongly associated with PTSD symptoms. We also found that routine work environment stress mediated the relationship between critical incident exposure and PTSD symptoms and between current negative life events and PTSD symptoms. Ensuring that the work environment is functioning optimally protects against the effects of duty-related critical incidents and negative life events outside police service