Persistence of multiple illnesses in World Trade Center rescue and recovery workers: a cohort study

Abstract

Background: More than 50,000 people participated in the rescue and recovery work that followed the Sept 11, 2001 (9/11) attacks on the World Trade Center (WTC). Multiple health problems in these workers were reported in the early years after the disaster. We report incidence and prevalence rates of physical and mental health disorders during the 9 years since the attacks, examine their associations with occupational exposures, and quantify physical and mental health comorbidities.

Methods: In this longitudinal study of a large cohort of WTC rescue and recovery workers, we gathered data from 27,449 participants in the WTC Screening, Monitoring, and Treatment Program. The study population included police officers, firefighters, construction workers, and municipal workers. We used the Kaplan-Meier procedure to estimate cumulative and annual incidence of physical disorders (asthma, sinusitis, and gastro-oesophageal reflux disease), mental health disorders (depression, post-traumatic stress disorder [PTSD], and panic disorder), and spirometric abnormalities. Incidence rates were assessed also by level of exposure (days worked at the WTC site and exposure to the dust cloud).

Findings: 9-year cumulative incidence of asthma was 27·6% (number at risk: 7027), sinusitis 42·3% (5870), and gastro-oesophageal reflux disease 39·3% (5650). In police officers, cumulative incidence of depression was 7·0% (number at risk: 3648), PTSD 9·3% (3761), and panic disorder 8·4% (3780). In other rescue and recovery workers, cumulative incidence of depression was 27·5% (number at risk: 4200), PTSD 31·9% (4342), and panic disorder 21·2% (4953). 9-year cumulative incidence for spirometric abnormalities was 41·8% (number at risk: 5769); three-quarters of these abnormalities were low forced vital capacity. Incidence of most disorders was highest in workers with greatest WTC exposure. Extensive comorbidity was reported within and between physical and mental health disorders.

Interpretation: 9 years after the 9/11 WTC attacks, rescue and recovery workers continue to have a substantial burden of physical and mental health problems. These findings emphasise the need for continued monitoring and treatment of the WTC rescue and recovery population.

Funding: Centers for Disease Control and Prevention and National Institute for Occupational Safety and Health.

Figure 1:. Cumulative Incidence of physical disorders in the World Trade Center Screening, Monitoring, and Treatment Program study population

Cumulative incidence of asthma (A). Cumulative incidence of sinusitis was similar in the intermediate and low exposure groups (B). Incidence of gastro-oesophageal reflux disease incidence was increased only in the very-high-exposure group compared with other groups (C). 9/11=September 11, 2001.

Figure 2:. Cumulative incidence of mental health disorders in New York City police officers and other rescue and recovery workers in the World Trade Center Screening, Monitoring, and Treatment Program study population

Symptoms of depression in police officers were similar in the very-high and high-exposure categories (A). Symptoms of depression in other rescue and recovery workers were similar in the high and intermediate exposure categories (B). Symptoms of post-traumatic stress disorder (PTSD) were more common in police officers with higher exposure (C). Higher levels of exposure were associated with increased rates of PTSD symptoms in other responders (D). Symptoms of panic disorders were more common in police officers with higher levels of exposure (E). High exposure levels were associated with increased rates of panic-disorder symptoms in other rescue and recovery workers (F). 9/11=September 11, 2001.

Figure 3:. Cumulative incidence of abnormal spirometry in the World Trade Center Screening, Monitoring, and Treatment Program study population

9/11=September 11, 2001.

Figure 4:. Physical comorbidities in the World Trade Center Screening, Monitoring, and Treatment Program study population

The Venn diagram shows the extent of comorbidity in World Trade Center rescue and recovery workers who reported ever having asthma, sinusitis, or gastro-oesophageal reflux disease.

Figure 5:. Mental health comorbidities in the World Trade Center Screening, Monitoring, and Treatment Program study population

High number of rescue and recovery workers had symptoms consistent with several of the mental health disorders assessed during the 9 year follow-up. PTSD= post-traumatic stress disorder.