Correlates and prevalence of post-traumatic stress disorders in the São Paulo metropolitan area, Brazil.

BACKGROUND

Post-traumatic stress disorder (PTSD) is a debilitating condition, which generates an extensive burden. We aimed to investigate in a huge metropolitan area, the prevalence of traumatic experiences, the development of PTSD, and its predictors.

METHODS

Traumatic experiences and PTSD were assessed in 5037 adult individuals of the general population. Cross-tabulations method assessed the prevalence of traumatic events and PTSD. Logistic regression models investigated predictors of lifetime and 12-month odds of PTSD and the conditional probability of developing PTSD for specific traumas.

RESULTS

Lifetime and 12-month diagnoses of PTSD were found in 3.2% and 1.6% of the sample. 'Witnessing anyone being injured or killed, or unexpectedly seeing a dead body' (35,7%) and 'being mugged or threatened with a weapon' (34.0%) were the two most reported traumas. The commonest events before PTSD onset were 'sudden unexpected death of a loved one' (34.0%), 'interpersonal violence' (31.0%), and 'threats to the physical integrity of others' (25.0%). Experiences related to "interpersonal violence" presented the highest conditional probability for PTSD (range 2.2-21.2%). Being 'sexually assaulted or molested' (21.2% total; 22.3% women; 0.0% men) and being 'raped' (18.8% total; 18.4% women; 20.1% men) were the two experiences with the highest odds for PTSD. While being female was a predictor of less exposure to any event (OR = 0.69), females were more prone to develop lifetime PTSD after exposure to an event (OR = 2.38).

CONCLUSION

Traumatic events are frequent in the general population and a small group of traumatic events accounts for most cases of subsequent PTSD.