Major Depression and Coronary Artery Disease in the Swedish Twin Registry

Abstract

Context Major depresssion (MD) and coronary artery disease (CAD) frequently co-occur. The mechanisms of comorbidity are uncertain. Objective To clarify sources of MD-CAD comorbidity. Design Major depression was assessed at the time of the personal interview, and CAD from hospital discharge records and death certificates. Setting Swedish population-based twin registry. Participants The study included 30 374 twins with a mean age of 57 years. Main Outcome Measure Modified DSM-IV diagnosis of MD or diagnosis of CAD. Results Lifetime association between MD and CAD was modest (odds ratio, ~1.3). In time-dependent Cox analyses, onset of CAD produced concurrent and ongoing hazard ratios for MD of 2.83 and 1.75. These risks increased if the diagnosis of CAD was restricted to myocardial infarction. Onset of MD increased the concurrent and ongoing hazard ratios for CAD to 2.53 and 1.17. The ongoing CAD risk was strongly associated with depressive severity and recurrence. Twin models showed that the modest comorbidity between MD and CAD in women arose primarily from shared genetic effects, although the genetic correlation was small (+0.16). In men, the source of comorbidity was moderated by age, being environmental in older members and largely genetic in younger members of the sample. Conclusions Although the MD-CAD relationship across the lifespan is modest, time-dependent models reveal stronger associations. The sustained effect of CAD onset on MD risk is much stronger than vice versa. The effect of MD on CAD is largely acute, and the longer-term effects are apparently mediated via depressive recurrence. When examined separately, in men, environmental effects, which are often acute, play a large role in MD-CAD comorbidity, whereas in women, chronic effects, which are in part genetic, are more important. In men, genetic sources of MD-CAD comorbidity are more important in younger members of the sample.

Associations Between Depression and Anxiety Symptoms and Retinal Vessel Caliber in Adolescents and Young Adults

“…Studies from this sample (as well as others) have shown that genetic factors play a significant role in retinal vessel caliber (39) and depression/anxiety (40). Moreover, a study of adult twins found a modest genetic correlation between depression and coronary artery disease (61). Thus, a natural question is whether the genetic factors underlying depression/anxiety and retinal vessel caliber overlap.…”

Posttraumatic stress disorder and incidence of type-2 diabetes: A prospective twin study

“…Genetic predisposition is substantial for obesity and other metabolic syndrome risk factors (Diamond, 2003; Jowett et al, 2009), as well as health behaviors, such as physical inactivity and diet (Heitmann, Harris, Lissner, & Pedersen, 1999; Lauderdale et al, 1997). Therefore, shared genetic pathways could potentially confound the association between PTSD and diabetes, as previously described for depression and cardiovascular disease (Kendler, Gardner, Fiske, & Gatz, 2009; Vaccarino et al, 2009). …”

Unipolar Depression and the Progression of Coronary Artery Disease: Toward an Integrative Model

“…In addition, depression persistence and/or treatment resistance are associated with longer episode duration [98,99] and a poor CAD prognosis [2,27]. Finally, the longer-term effects of depression on CAD are mediated by chronic/recurrent depression [100]. …”