Depression has long had a popular link to cardiovascular disease and death. However, only during the last 15 years scientific evidence supporting this common wisdom has been available (Glassman et al., 2007a).
Since the early 1990s studies have reported prevalences of major depression between 17% and 27% in hospitalized patients with coronary artery disease (CAD) (Rudisch & Nemeroff, 2003).
It is becoming clear that the comorbidity of depression and cardiovascular disease does not occur by chance but the mechanisms responsible for this relationship is poorly understood. Platelet abnormalities, autonomic tone, and health behaviors have all been implicated. There exists also the possibility that depression and vascular disease share certain vulnerability genes (McCaffery et al., 2006).
Moreover, it is now apparent that depression aggravates the course of multiple cardiovascular conditions (Glassman et al., 2007) and has regularly been shown to lower adherence to prescribed medication and secondary prevention measures (Glassman et al., 2007b).
Few randomized controlled trials have evaluated the efficacy of treatments for major depression in patients with coronary artery disease.
Depression and cardiovascular disease
- Depression observed following acute coronary syndrome (ACS) is common and associated with an increased risk of mortality. Medically healthy individuals who suffer from depression are at significantly increased risk of developing heart attacks and strokes later in life (Glassman et al., 2007).
- Acute coronary syndrome is both psychologically and physiologically stressful, and it is common to attribute depression observed following ACS to that stress (Glassman et al., 2006)
Furthermore, the Heart rate variability (HRV), a well-recognized measure reflecting fluctuations in autonomic activity, is an independent predictor of death. Earlier studies show that, after myocardial infarction, HRV values increase approximately 50% between 3- and 12-weeks. In post-ACS patients with depression, improvement in HRV could therefore result from the pharmacological action of an antidepressant drug, from an improving mood independent of the drug, or as a result of recovery from the acute cardiac injury.
Depression treatment among patients with coronary artery disease
Few adequately controlled trials evaluated whether antidepressant treatments are either safe or effective in patients with coronary artery disease (CAD). The largest of these, the Sertraline Antidepressant Heart Attack Trial (SADHART) (Glassman et al., 2002) was designed to evaluate the safety and efficacy of sertraline hydrochloride for treatment of MDD in ACS. No adverse cardiovascular effects of sertraline treatment were detected, sertraline was both safe and effective in post-MI depression and observed a reduction in death and recurrent myocardial infarction. Planned subgroup analyses showed a clear benefit of sertraline over placebo for patients with recurrent depression and those with more severe depression.