Diabetes, Depression, and Cardiovascular risk

Diabetes and depression are major public issues that often co-occur. Both diseases affect a growing number of people worldwide and are projected to be among the five leading causes of disease burden in 2030. Approximately 10-30 % of the people with type 1 (5-10 % of all diabetes cases) or type 2 diabetes is affected by depression. There is ample evidence that the association between type 2 diabetes and depression is bidirectional. Depression is likely to increase the risk of cardiovascular complications and mortality in people with diabetes. Several behavioral mechanisms (e.g., treatment nonadherence, physical inactivity, and poor diet) and biological mechanisms (e.g., deregulation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system, vascular pathology, and central obesity) explain the link between depression and cardiovascular risk in diabetes patients. It has been postulated that treatment of depression could improve cardiovascular outcomes. Due to limited number of studies, there is currently no convincing evidence that pharmacological or psychological treatment of depression improves cardiovascular outcomes. Various organizations suggest screening for depression in their guidelines or recommendations for diabetes care. At present, there is no substantial evidence of the effectiveness of screening for depression among diabetes patients and is therefore not recommended. Future trials should focus on (a) the development of innovative interventions that can help to prevent depression, type 2 diabetes, and cardiovascular diseases in a cost-effective way and (b) long-term prospective studies that disentangle the mechanisms that link depression with unfavorable cardiovascular risks in diabetes patients.