3.1. Sample characteristics and location during the attacks of 9/11, 2001
The sample was composed primarily of low-income, Hispanic patients, who were born outside of the United States and had little formal education. Females accounted for 69.6% of the patients; mean age was 51.2 (S.D.=11.9) years; 55.3% had not graduated from high school; 75.9% reported an annual family income of less than $12,000; 70.0% had never married or were currently separated, divorced or widowed, and only 20.0% of the patients reported they were paid workers. The percentage of the sample who had immigrated to the United States was 81.1%; 81.9% were of Hispanic origin, predominantly from the Dominican Republic (78.7%), followed by Puerto Rico (8.7%) and other Spanish-speaking countries (7.6%). Of the non-Hispanic patients, 73.2% were black. Notably, 38% of all patients reported a family psychiatric history and 62% reported pre-9/11 exposure to trauma.
The majority (78.2%) of the patients reported that they were in NYC during the 9/11 attacks and another 3.8% reported being in the WTC or in lower Manhattan below 14th Street. More than a quarter (27.1%) reported knowing someone who was killed during the 9/11 attacks.
3.2. PTSD and sociodemographic and exposure characteristics
Seven to 16 months after 9/11, the prevalence estimates of current 9/11-related probable PTSD in this sample ranged from 4.7% (based on a strict definition: PCL-C score of 50 or over) to 10.2% (based on DSM-IV criteria). Probable PTSD (hereafter referred to as PTSD) was significantly related to female gender, being born outside of the United States, not being married or cohabiting, and having a family history of psychiatric disorders and pre-911 trauma exposure (). No significant differences in PTSD were found between patients from Puerto Rico (3.0%; n =2/66) as compared to the Dominican Republic (5.7%; n =34/600) and to other Spanish-speaking countries (5.2%; n =3/58) ( P=.76; Fisher's exact test with df=2).
Prevalence rates of current 9/11-related probable PTSDa, by patient background characteristics
Mean PCL-C scores in patients interviewed 7–12 months after the attacks (n =491) significantly declined during this period (t =–4.38, P<.0001) (). Starting at the first year anniversary (9/11/2002), PCL-C scores (n =439) started to increase. We found a marginally positive time trend (t =1.92, P=.055). The two slopes (pre-anniversary and post-anniversary) were significantly different (t =3.13, P=.002).
Fig. 1 Each dot represents a PCL-C score for a single participant plotted above the date of the interview. Separate lines of best fit are shown for two periods: (a) between study start on April 1, 2002, and the 1-year anniversary of 9/11 on September 11, 2002; (more ...)
Proximity to the epicenter of the attacks was not significantly associated with PTSD; however, the likelihood of PTSD tended to increase with closer proximity. Those outside of NYC on September 11, 2001, had a PTSD rate of 8.0% (16/201), those in NYC but not in lower Manhattan had a rate of 10.6% (73/692) and those in lower Manhattan or in the WTC itself had a rate of 17.1% (6/35) ().
Rates of current 9/11-related probable PTSD stratified by type of exposure to the WTC attacks
PTSD was more common among patients who reported that they lost a person due to the attacks of 9/11 compared to those who did not experience such loss ().
To test whether indirect exposure to the attacks is associated with PTSD independent of family psychiatric history and history of trauma, we examined the prevalence of probable PTSD in patients who were not directly exposed to the attacks and reported no family psychiatric history or past trauma exposure (N=178). None of these participants screened positive for PTSD.
3.3. Psychiatric comorbidity
The majority of the patients with PTSD (68.4%) met criteria for a positive screen of one or more other mental disorder. The most frequent comorbid disorders were MD (57.9%) and GAD (33.7%) (). After adjustment for demographic and exposure covariates, PTSD remained strongly associated with each of the anxiety and mood disorders.
Mental health diagnoses and impairment/health status among patients with and without 9/11-related probable PTSD
Almost one fifth (17.9%) of the patients with PTSD, as compared with 3.3% of those without PTSD, reported suicidal ideation at least some days during the previous 2 weeks (). After controlling for the presence of MDD, demographic and exposure covariates, PTSD did not remain significantly associated with current suicidal ideation.
3.4. Impairment, functioning and health
Significant social and family life impairment were more common among patients with PTSD than those without it (). Impairment in both areas remained strongly associated with PTSD after adjusting for demographic and exposure covariates and the presence of any current mental disorder.
Work loss of 1 week or more in the past month was also more commonly reported by patients with PTSD than by those without and was significantly associated with PTSD after controlling for demographic and exposure covariates and the presence of any current mental disorder (). Finally, mental and physical health-related quality of life were worse for those with PTSD than for those without PTSD (). The group difference in SF-12 Mental Component Summary scores remained statistically significant after controlling for demographic and exposure covariates and the presence of any current comorbid mental disorder.
3.5. Mental health treatment and utilization of medical services
Half (50%) of the patients with PTSD reported taking a prescribed psychotropic medication in the last month, and the most commonly reported medications were antidepressants (48.9%). More than one third (39.8%) of the patients with PTSD reported receiving mental health treatment (). A history of previous mental health hospitalization was significantly more commonly reported by patients with PTSD than those without PTSD. In logistic regression models that adjusted for demographic and exposure covariates, PTSD remained significantly associated with the use of prescribed psychotropic medications and antidepressant drug and previous mental health hospitalization.
Mental health treatment in the past month, and visits in the first year after 9/11 attacks, among patients with and without 9/11-related probable PTSD
9/11-related current PTSD was not associated with making an ER visit, being admitted to a hospital or the number of outpatient visits made during the 12-month post-9/11 period, in either the crude or adjusted analyses.