The use of antidepressant medication is strongly associated with the risk of developing diabetes, according to findings published in the March issue of Diabetes Care.

Dr. Richard R. Rubin, of Johns Hopkins University School of Medicine, Baltimore, Maryland, and colleagues point out that among diabetics, the risk of depression is 50 to 100% greater than in the general population. Furthermore, depression in diabetic patients is associated with higher complication and mortality rates and higher health care costs.

In 3187 participants in the randomized Diabetes Prevention Program (DPP) study, Dr. Rubin's team sought to determine whether depression symptoms or antidepressant use were associated with progression to type 2 diabetes, and whether the associations varied depending on the treatment arm: standard lifestyle recommendations plus 850 mg metformin twice daily (MET arm), standard lifestyle recommendations plus placebo (PLB arm), or an intensive lifestyle modification program (ILS arm).

The mean follow-up was 3.2 years.

At baseline, 10.3% of subjects had Beck Depression Inventory (BDI) scores indicating at least mild depression (11 or higher), and 5.7% were taking antidepressants. Intermittent antidepressant use was reported for 7.2% of total person-years during the DPP, and continuous antidepressant use was reported for 3.2% of total person-years.

No association was observed between elevated BDI scores at baseline or during the study and diabetes risk in any treatment arm when other factors associated with the risk of developing diabetes were controlled for.

"Baseline antidepressant use, on the other hand, was strongly associated with diabetes risk" in both the PLB and ILS arms (hazard ratios [HR] 2.25 and 3.48, respectively), according to the report.

Compared with no use, continuous antidepressant use during the study was also associated with diabetes risk in the PLB (HR 2.60) and ILS (HR 3.39) arms. Intermittent antidepressant use during the study was associated with diabetes risk in the ILS arm (HR 2.07). No association was found between antidepressant use and development of diabetes among participants in the MET arm.

"If antidepressants prove to be an independent diabetes risk factor, clinicians will need to consider this when prescribing depression treatment in patients at high risk for diabetes," Dr. Rubin said in an interview with Reuters Health. "One possibility is to consider psychological treatment to avoid potential iatrogenic effects of antidepressants (although limited resources may often make this unfeasible)," he explained. "In one study of depressed patients with diabetes who had high A1c levels, cognitive behavioral therapy counseling was associated with improved glycemic control; this suggests a potential benefit for patients at high risk for developing diabetes."

"This paper was based on data from the DPP, with average participant follow-up of 3.2 years," Dr. Rubin notes. "We have continued to follow these participants and now have an additional 5 years of data," he said. "We will soon analyze the longer term data to see if the associations we found during the DPP are sustained."