Predictors of the co-occurrence of posttraumatic stress disorder and depressive disorder in psychiatric outpatients.

INTRODUCTION

We explored the predictors of co-occurring depressive disorder (DD) in individuals with posttraumatic stress disorder (PTSD) in an outpatient psychiatric setting.

METHODS

Participants (N = 170; mean age = 40.78, SD = 16.15 years; 58.8% women) included 71 adult patients who met the criteria for a PTSD diagnosis and 99 adult patients who met the criteria for a comorbid PTSD/DD diagnosis. Potential predictors included trauma types (focusing on trauma characteristics), history of previous traumatic experiences (i.e., the number of lifetime traumatic events before current trauma and childhood maltreatment), and post-trauma variables (i.e., elapsed time since the current traumatic event and the severity of PTSD symptoms).

RESULTS

A logistic regression analysis-including demographic variables, trauma types, history of previous traumatic experiences, and post-trauma variables that showed significant differences between the two groups-was conducted. The effects of repeated trauma (OR = 13.18, 95% CI [3.44, 50.48], p < .001), the number of lifetime traumatic events (OR = 1.04, 95% CI [1.01, 1.51], p = .044), and childhood maltreatment (OR = 1.23, 95% CI [1.01, 1.51], p = .004) were associated with a greater likelihood of concurrent PTSD/DD.

CONCLUSION

Cumulative characteristics such as maltreatment and the number of lifetime traumatic events before the current trauma as well as repetitive properties of the most recent trauma present a key risk factor for co-occurring PTSD/DD.