Shiner B (Quality Scholars), Watts BV
The DSM-IV criteria for PTSD are designed to have prognostic implications in the treatment of PTSD. The PCL-M is a 17-item self-report instrument that identifies the presence or absence of criteria B, C, and D. Debate exists as to whether it is essential to meet the required three of seven symptoms in criterion C in order to have PTSD. Those with two of seven symptoms in criterion C have been said to have “partial PTSD.” Using longitudinally-collected data from a walk-in mental health clinic at a VAMC, we sought to understand the functional impact of having full versus partial PTSD and to examine the comparative stability of these diagnoses over time.
Veterans presenting from February 2005 through December 2007 completed a battery of self-report assessments, including the PCL-M, SF-36, BDI, and STAI. First, we determined the significance of having full PTSD on functional level. Examining first-visit data, we calculated odds ratios for having full PTSD as a function of SF-36 MCS score when controlled for age. Subsequently, the model was controlled for PTSD severity (PCL-M score), and then for depression (BDI score) and anxiety (STAI subscores). Second, we determined the stability of full versus partial PTSD diagnoses. Examining follow-up data, Kaplan-Meyer survival analysis was performed to track patients with full versus partial PTSD.
Of 1962 veterans (91% male) completing an initial assessment battery, 935 (48%) met full criteria and 66 (3%) met partial criteria for PTSD. When controlled for age, those with higher MCS scores were 8% less likely to suffer PTSD (OR 0.92:0.91,0.93;p < 0.001). However, the difference disappeared when controlled for PTSD severity. Controlling for severity of depression and anxiety did not have further effects on the model. The median survival time for full PTSD diagnosis was 986 days, compared to 305 days for partial PTSD diagnosis (p < 0.001).
While patients with full and partial PTSD had similar functional impairments upon presentation, the diagnosis of full PTSD was significantly more stable over time than partial PTSD.
These data suggest that full PTSD is a persistent syndrome in this population and that the natural history of full PTSD differs from that of partial PTSD.