The prevalence of MDD in individuals exposed to low-risk traumatic events was significantly greater than that in individuals who reported no trauma exposure (36.8% vs 24.4%, χ12=38.4, P < .001). The MDD prevalence in individuals exposed to high-risk trauma was more than double that in those without trauma exposure, with nearly half meeting the criteria for the disorder (49.4% vs 24.3%, χ12=120.9, P < .001). The comorbidity of PTSD and MDD was also high: 67.9% of individuals who met criteria for PTSD also met MDD criteria compared with only 32.6% of those who had been exposed to trauma (either low or high risk) but did not develop PTSD ( χ12=125.9, P < .001).
