Abstract 14272: Posttraumatic Stress Disorder, Major Depression and Incidence of Coronary Heart Disease
Background. Posttraumatic stress disorder (PTSD) is an emerging risk factor for CHD, but is comorbid with major depressive disorder (MDD), an established CHD risk factor. We sought to determine the relative contributions of PTSD and MDD to CHD risk.
Methods. We conducted a prospective study of monozygotic and dizygotic middle-aged male twins of the Vietnam Era Twin Registry. Lifetime diagnoses of PTSD and MDD were assessed at baseline in 1990-1991 with the Diagnostic Interview Schedule. Among twin pairs free of CHD at baseline, we selected three groups: 1) pairs discordant for PTSD, 2) pairs discordant for MDD, 3) pairs without a history of PTSD or MDD. These underwent a follow-up clinic visit and [N13]PET myocardial perfusion imaging between 2002-2010 (median follow-up 15 yr). Outcomes included CHD (previous myocardial infarction, unstable angina, and coronary revascularization) and stress total severity score (STSS) quantifying myocardial perfusion abnormalities. GEE and mixed models were used to account for pair cluster and to separate between- and within-pair effects.
Results. A total of 540 twins (270 pairs) were included, with mean age at baseline of 41 yr (range 34-48). Of these, 110 pairs were discordant for a lifetime diagnosis of PTSD and 109 for MDD. The incidence of CHD was higher in twins with PTSD only (23%) or PTSD and MDD (21%), intermediate for those with MDD only (13%) and lowest for those with neither (8%). When PTSD and MDD were included in the same model adjusting for demographic and behavioral factors, the relative risk for PTSD was 1.9 (p=0.01), and for MDD it was 1.3 (p=0.22). Within twin pair results were similar with RRs of 1.8 (p=0.03) for PTSD and 1.2 (p=0.54) for MDD. PTSD, but not MDD, was also associated with higher STSS, denoting more perfusion defects. The mean STSS was 162 in twins with PTSD and 110 in their brothers without PTSD (p=0.01). Corresponding results for MDD were 115 and 131 (p=0.43).
Conclusions. Among Vietnam era veterans, PTSD is a more robust risk factor for CHD than MDD. Comorbidity of PTSD and MDD does not increase the risk associated with PTSD alone.
- © 2011 by American Heart Association, Inc.