A lower frequency of depressive episodes is associated with a 34% decreased risk of coronary artery disease and a 33% decreased risk of type 2 diabetes, irrespective of lifestyle risk factors and genetic susceptibility. The findings are published in Nature Cardiovascular Research.

The prevalence of unrecognized depression in patients with heart disease has been known for more than 40 years. However, it is unclear whether depression contributes to the development of heart disease or whether it is mostly secondary to the clinical condition.

Pradeep Natarajan and colleagues studied the genomes of 328,152 individuals of European ancestry (aged between 40 and 69 years old) available in the UK Biobank. These data allowed the authors to generate a polygenic risk score—a specialized tool that can be used to refine risk prediction for heart disease. The authors reveal that a lower burden of depressed mood is associated with a decreased risk of coronary artery disease, type 2 diabetes and atrial fibrillation by 34%, 33% and 20%, respectively. This observed association was found to be independent of lifestyle factors known to be associated with both poor mental health and the risk of developing cardiovascular disease, such as diet, exercise and smoking. In addition, the association between depression and coronary artery disease was higher in women than in men.

This study expands our knowledge of the potential contributing role of depression in the development of cardiovascular disease. The authors conclude, however, that future research will be needed to determine the mechanisms behind this observed association and to identify potential implications for preventive therapies.