Post-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.

Data 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.

CFAs 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.

Results 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.

Longitudinal 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.

A 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.

Among 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.

Trajectories 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.

Whether individual differences in cortisol contribute to subsequent major depressive disorder (MDD) is unknown.

To determine whether premorbid levels of salivary cortisol and dehydroepiandrosterone (DHEA) were associated with subsequent MDD and how these related to psychosocial factors known to increase the risk for MDD.

Adult women (n=116) were recruited from general practices. None was currently depressed; 83 were ‘psychosocially vulnerable’ to MDD, 33 were not. Salivary steroids (cortisol and DHEA at 08.00 h and 20.00 h), recent life events, current mood and social support were assessed at entry. Onset of MDD was recorded during 13 months' follow-up.

There were no associations between salivary cortisol or DHEA and recent life events or vulnerability. Twenty-eight onsets of MDD occurred during the follow-up period. This was associated with: severe adverse life events and difficulties during the follow-up period; mean morning cortisol levels at entry; and the presence of any of three vulnerability factors.

Individual differences in morning salivary cortisol levels may represent an independent risk factor for subsequent MDD. The origin of these differences in cortisol is not yet understood.

Many state and local emergency medical services (EMS) systems may wish to modify provider levels and their scope of practice to align their systems with the recommendations of the National Emergency Medical Services Education and Practice Blueprint. To determine any changes that may be needed in a typical EMS system, the knowledge and skills of EMS providers in one rural area of North Carolina were compared with the knowledge and skills recommended in the National Emergency Medical Services Education and Practice Blueprint.

A survey listing 175 items of patient care-oriented knowledge and skills described in the National Emergency Medical Services Education and Practice Blueprint was developed. EMS providers from five rural eastern North Carolina counties were asked to identify on the survey those items of knowledge and skills they believed they possessed. The skills and knowledge selected by the respondents at the five different North Carolina levels of certification were compared with the knowledge and skills listed for comparable provider levels delineated by the National Emergency Medical Services Education and Practice Blueprint. The proportions of the recommended skills reported to be possessed by the respondents were compared to determine which North Carolina certification levels best correlate with the Blueprint.

One hundred forty-five EMS providers completed the survey. The proportion of recommended skills and knowledge reported to be possessed by Emergency Medical Technicians (EMTs) ranked significantly lower than did the skills and knowledge reported to be possessed by respondents at other levels in five of the 10 Blueprint elements. The proportion of recommended skills and knowledge reported to be possessed by EMT-Defibrillator-level personnel ranked lower than did those reported to be possessed by respondents at other levels in seven of the 10 Blueprint elements. The proportion of recommended skills and knowledge reported to be possessed by EMT-Intermediates ranked lower than did those reported to be possessed by respondents at other levels in nine of the 10 Blueprint elements. The proportion of recommended skills and knowledge reported to be possessed by EMT-Advanced Intermediates ranked lower than were the skills and knowledge reported to be possessed by respondents at other levels in two of the 10 Blueprint elements. Finally, the proportion of recommended skills and knowledge reported to be possessed by EMT-Paramedics ranked lower than were those reported to be possessed by respondents at other levels in one of the 10 Blueprint elements.

In North Carolina, combining the EMT and EMT-Defibrillator levels and eliminating the EMT-Intermediate level would create three levels of certification, which would be more consistent with levels recommended by the Blueprint. The results of this study should be considered in any effort to revise the levels of EMS certification in North Carolina and in planning the training curricula for bridging those levels. Other states may require similar action to align with the National Emergency Medical Services Education and Practice Blueprint.