Michael A. Crane

Trajectories of PTSD risk and resilience in World Trade Center responders: An 8-year prospective cohort study

BACKGROUNDnLongitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders.nnnMETHODnA total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks.nnnRESULTSnAmong police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories.nnnCONCLUSIONSnTrajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.

Dimensional structure and course of post-traumatic stress symptomatology in World Trade Center responders.

BACKGROUNDnPost-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations.nnnMETHODnData were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11.nnnRESULTSnCFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time.nnnCONCLUSIONSnResults of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.

Cohort Profile: World Trade Center Health Program General Responder Cohort

Cohort Profile: World Trade Center Health Program General Responder Cohort Christopher R Dasaro,* William L Holden, Karen D Berman, Michael A Crane, Julia R Kaplan, Roberto G Lucchini, Benjamin J Luft, Jacqueline M Moline, Susan L Teitelbaum, Usha S Tirunagari, Iris G Udasin, Jean H Weiner, Patrice A Zigrossi and Andrew C Todd Icahn School of Medicine at Mount Sinai, Department of Preventive Medicine, New York, NY, USA, Stony Brook University Medical Center, Department of Medicine, Stony Brook, NY, USA, Hofstra North Shore-LIJ School of Medicine at Hofstra University, Department of Occupational Medicine, Epidemiology and Prevention, Hempstead, NY, USA and Robert Wood Johnson Medical Center, Environmental and Occupational Health Sciences Institute, Piscataway, NJ, USA

The response to September 11: a disaster case study.

BACKGROUNDnThe response to 9/11 continues into its 14th year. The World Trade Center Health Program (WTCHP), a long-term monitoring and treatment program now funded by the Zadroga Act of 2010, includes >60,000 World Trade Center (WTC) disaster responders and community members (survivors). The aim of this review is to identify several elements that have had a critical impact on the evolution of the WTC response and, directly or indirectly, the health of the WTC-exposed population. It further explores post-disaster monitoring efforts, recent scientific findings from the WTCHP, and some implications of this experience for ongoing and future environmental disaster response.nnnFINDINGSnTransparency and responsiveness, site safety and worker training, assessment of acute and chronic exposure, and development of clinical expertise are interconnected elements determining efficacy of disaster response.nnnCONCLUSIONnEven in a relatively well-resourced environment, challenges regarding allocation of appropriate attention to vulnerable populations and integration of treatment response to significant medical and mental health comorbidities remain areas of ongoing programmatic development.

Mortality among World Trade Center rescue and recovery workers, 2002–2011

BACKGROUNDnRescue and recovery workers responding to the 2001 collapse of the World Trade Center (WTC) sustained exposures to toxic chemicals and have elevated rates of multiple morbidities.nnnMETHODSnUsing data from the World Trade Center Health Program and the National Death Index for 2002-2011, we examined standardized mortality ratios (SMR) and proportional cancer mortality ratios (PCMR) with indirect standardization for age, sex, race, and calendar year to the U.S. general population, as well as associations between WTC-related environmental exposures and all-cause mortality.nnnRESULTSnWe identified 330 deaths among 28,918 responders (SMR 0.43, 95%CI 0.39-0.48). No cause-specific SMRs were meaningfully elevated. PCMRs were elevated for neoplasms of lymphatic and hematopoietic tissue (PCMR 1.76, 95%CI 1.06-2.75). Mortality hazard ratios showed no linear trend with exposure.nnnCONCLUSIONSnConsistent with a healthy worker effect, all-cause mortality among responders was not elevated. There was no clear association between intensity and duration of exposure and mortality. Surveillance is needed to monitor the proportionally higher cancer mortality attributed to lymphatic/hematopoietic neoplasms.

Implications of the World Trade Center Health Program (WTCHP) for the Public Health Response to the Great East Japan Earthquake

The attacks on the World Trade Center (WTC) on September 11, 2001 resulted in a serious burden of physical and mental illness for the 50,000 rescue workers that responded to 9/11 as well as the 400,000 residents and workers in the surrounding areas of New York City. The Zadroga Act of 2010 established the WTC Health Program (WTCHP) to provide monitoring and treatment of WTC exposure-related conditions and health surveillance for the responder and survivor populations. Several reports have highlighted the applicability of insights gained from the WTCHP to the public health response to the Great East Japan Earthquake. Optimal exposure monitoring processes and attention to the welfare of vulnerable exposed sub-groups are critical aspects of the response to both incidents. The ongoing mental health care concerns of 9/11 patients accentuate the need for accessible and appropriately skilled mental health care in Fukushima. Active efforts to demonstrate transparency and to promote community involvement in the public health response will be highly important in establishing successful long-term monitoring and treatment programs for the exposed populations in Fukushima.

Sex differences in asthma and gastroesophageal reflux disease incidence among the World Trade Center Health Program General Responder Cohort.

BACKGROUNDnAsthma and gastroesophageal reflux disease (GERD) are two common conditions among the responders to the WTC attacks. This study examined whether the cumulative incidence rates of asthma and GERD differed by sex among 24,022 and 23,557 WTC responders, respectively.nnnMETHODSnCox proportional hazards regression was used to examine the sex difference in the rate of onset of physician-diagnosed asthma or GERD, from 9/12/2001 through 12/31/2015.nnnRESULTSnThe cumulative incidence of asthma reached 23% for women and 17% for men by the end of 2015, and the cumulative incidence of GERD reached 45% for women and 38% for men. Comparing women to men, the hazard ratio was 1.48 (95% confidence interval (CI): 1.27, 1.74) for asthma, and 1.25 (95% CI: 1.13, 1.38) for GERD.nnnCONCLUSIONSnWTC general responders have a substantial burden of asthma and GERD, with higher incidence in women. Am. J. Ind. Med. 59:815-822, 2016.

Development of a Physiological Frailty Index for the World Trade Center General Responder Cohort

Responders to the 9/11/2001 WTC attacks were exposed to multiple toxic pollutants. Since 2002, the health of the responder cohort has been continuously tracked by the WTC Health Monitoring Program. However, no assessments have been made of frailty, an important health metric given the current average age of the WTC responder cohort (55 years). In this study, we use laboratory test results and other physiological parameters to construct a physiological frailty index (FI-Lab) for this cohort. The study sample comprised responders aged 40 years or older who completed a health monitoring visit at Mount Sinai Center within the past 5 years. For each subject, FI-Lab was computed as the proportion of 20 physiological parameters (lab tests, pulmonary function, and blood pressure) on which the subject had abnormal values. Using negative binomial regression models, we tested FI-Labs association with the SF-12 wellbeing score and various demographic characteristics. FI-Lab showed strong associations with the physical and mental components of the SF-12 as well as age, race, and smoking status. Using a cutoff of 0.25 to define presence of physiological/preclinical frailty, we found frailty prevalence in the study sample to be approximately 12%. This study demonstrates the feasibility of assessing preclinical frailty in the WTC responder cohort.

Assessment of cumulative health risk in the World Trade Center general responder cohort

BACKGROUNDnMultiple comorbidities have been reported among rescue/recovery workers responding to the 9/11/2001 WTC disaster. In this study, we developed an index that quantifies the cumulative physiological burden of comorbidities and predicts life expectancy in this cohort.nnnMETHODSnA machine learning approach (gradient boosting) was used to model the relationship between mortality and several clinical parameters (laboratory test results, blood pressure, pulmonary function measures). This model was used to construct a risk index, which was validated by assessing its association with a number of health outcomes within the WTC general responder cohort.nnnRESULTSnThe risk index showed significant associations with mortality, self-assessed physical health, and onset of multiple chronic conditions, particularly COPD, hypertension, asthma, and sleep apnea.nnnCONCLUSIONnAs an aggregate of several clinical parameters, this index serves as a cumulative measure of physiological dysregulation and could be utilized as a prognostic indicator of life expectancy and morbidity risk.