Researchers from University of Connecticut in Farmington reported that depression is associated with low insulin sensitivity and that treatment of depression decreases insulin resistance.
The study results of depressed adults in a diabetes prevention program were presented at the American Diabetes Association (ADA) 69th Scientific Sessions.
The findings from 56 obese adults at risk for type 2 diabetes and symptoms of metabolic syndrome were presented by Julie Wagner, PhD, associate professor in the Division of Behavioral Sciences and Community Health at the University of Connecticut Health Center.
Mean age was 46 years (±13 years), mean body mass index was 39 kg/m2 (±7 kg/m2), mean waist circumference was 44 inches (±7 inches), mean fasting glucose was 96 mg/dL (±12 mg/dL), and whole-body insulin sensitivity was 3.1 (±1.9). Of the cohort, 90% were female and 53% were white.
The risk factors for type 2 diabetes also included family history, delivery of a baby of 9 pounds or larger, hypertension, gestational diabetes, high low-density-lipoprotein cholesterol, high triglycerides, and low high-density-lipoprotein cholesterol.
The study excluded individuals with a history of a 2-hour postprandial glucose load of 200 mg/dL or higher or a history of treatment with metformin for impaired glucose tolerance.
Subjects were categorized into 1 of 3 groups: nondepressed (57%); depressed (23%), defined as a score of 16 or greater on the Centers for Epidemiologic Studies Depression (CESD) Scale; or treated for depression (20%).
Mean CESD score was 5.2 (±3.0) for nondepressed subjects, 28.6 (±9.6) for depressed subjects, and 19.6 (±12.2) for those treated for depression.
Dr. Wagner reported that nearly half of those treated for depression (46%) scored above 16 on the CESD Scale which means that these patients still showed signs of significant depression despite treatment.
The Physical Activity subscale of the Health Promoting Lifestyle Profile 4-point scale was used to document the level of physical activity. The depression scores reported by Dr. Wagner were inversely correlated with physical activity (r = –0.36) and insulin sensitivity (r = –0.30).
Subjects with untreated depression had significantly lower insulin sensitivity (mean insulin sensitivity, 1.79 ± 0.91) than nondepressed individuals (mean insulin sensitivity, 3.39 ± 1.78; P < .05).
Adults treated for depression had insulin sensitivities similar to nondepressed adults (mean, 3.10 ± 1.86; P = .63). The association remained after controlling for physical activity (P = .28).
Depressed subjects have a 37% increased risk of developing diabetes, Dr. Wagner noted during her presentation. Evidence indicates that insulin resistance and depression are related.
Treatment for depression in adults at risk for type 2 diabetes may improve insulin resistance, Dr. Wagner told Medscape Diabetes & Endocrinology. Further research is needed to determine if treatment of depression contributes to delaying or decreasing the risk for type 2 diabetes.
This is a very significant study, told R. Paul Robertson, MD, ADA’s president of medicine and science and an endocrinologist at Swedish Medical Center in Seattle, Washington.
Treatment of depression, effective treatment, is critical, and I’m not talking about just with drugs. Patients may only need counseling, but the depression is something that needs to be addressed, Dr. Robertson emphasized.
Depression is tied up with a lot of the issues surrounding diabetes. Obesity is a big part of this disease, and the more overweight patients are, the more depressed they get, and the more inactive they get, as you can see in [Dr. Wagner’s] study, the worse the depression. It is a vicious cycle.
Effective treatment of the depression might [stop] the cycle, Dr. Robertson said. With effective treatment, patients will tend to change some of their other behaviors that increase the risk for type 2 diabetes.
The bigger question, Dr. Robertson observed, is whether the depression is part of the diabetes or part of chronic disease in general.