Depression significantly increased risk for mortality in people with type 2 diabetes

People with type 2 diabetes who were also depressed were at increased risk for mortality — far exceeding mortality associated with cardiovascular disease, according to researchers.

In the prospective cohort study, the researchers examined the association of depression with all-cause and cause-specific mortality in 4,184 people with type 2 diabetes. Depression was assessed at baseline with the Patient Health Questionnaire, and medical records were reviewed to determine causes of death.

During follow-up, 428 patients without depression (12.9%) died compared with 88 patients (17.8%) with major depression and 65 patients (18.2%) with minor depression.

Causes of death were grouped as deaths from CVD (42.7%), deaths from cancer (26.9%) and deaths not caused by CVD or cancer (30.5%). The most common causes of mortality in the group of patients without CVD or cancer were infection, dementia, renal failure and chronic obstructive pulmonary disease.

After adjusting for demographic characteristics, baseline major depression was significantly associated with all-cause mortality (HR=2.26; 95% CI, 1.79-2.85), CV mortality (HR=2.0; 95% CI, 1.37-2.94) and non-CV and noncancer mortality (HR=3.35; 95% CI, 2.30-4.89).

Major depression was associated with all-cause mortality (HR=1.52; 95% CI, 1.19-1.95) and with death not caused by cancer or atherosclerotic CVD (HR=2.15; 95% CI, 1.43-3.24) after additional adjustment for baseline clinical characteristics and health habits. Minor depression showed similar associations but they were nonsignificant. – by Jennifer Southall

Lin EHB. Ann Fam Med. 2009;7:414-421.

This study reminds us of the pervasiveness of depression among those with type 2 diabetes. Living with diabetes is challenging enough. Untreated depression makes it even more difficult for patients to adhere to a diabetes self-care regimen. The diabetes educator is positioned to assist with the depression screening process. Self-management education programs should include a validated diabetes screening tool as part of their routine assessment, and the results should be communicated to the referring physician. Timely screening and identification of depression can open the door for optimal treatment. By facilitating behavior change such as medication adherence, smoking cessation and healthy eating that can lead to weight loss, diabetes educators' efforts can mediate the comorbidities so common among those with diabetes.

– Virginia Zamudio Lange RN, MSN, CDE

Endocrine Today Editorial Board member