TUCSON, ARIZ. — Depression is a risk factor for poor glycemic control in diabetic patients infected with hepatitis C, according to an analysis of data from a preliminary cohort study in 462 patients.
The association between depression and glycemic control is noncausal at this point, but warrants further study and attention by family physicians, said Dr. Anthony Valdini, research director of the Greater Lawrence Family Health Center, Lawrence, Mass.
Diabetes mellitus type 2 (DM2) and depression are common comorbidities among patients infected with the hepatitis C virus (HCV). Interferon, a major component of HCV therapy, often is a cause of depression. But physicians have been hesitant to prescribe antidepressants in this population because of what Dr. Valdini believes are unfounded fears of liver complications.
“This is a group that is miserable,” Dr. Valdini said during a poster presentation at the annual meeting of the North American Primary Care Research Group. “In some series, you will get up to 58% of people who are depressed, so it's really cruel to treat them for hepatitis C and not offer them therapy for their depression.”
Dr. Valdini and colleagues used data from the hepatitis C registry to identify 462 patients with hepatitis C, aged 21 years or older, who had visited an inner-city community health center between April 2003 and April 2005.
Patients were coded as either depressed or diabetic if these diagnoses were found in their medical records. The most recent hemoglobin A1c (HbA1c) value was used for calculations. They compared hepatitis-positive diabetics with and without depression by using chi-squared statistics, after categorizing HbA1c results into tertiles representing levels of glycemic control (<7%, 7%–9.5%, >9.5%).
Overall, 139 patients (30%) were depressed and 83 (18%) had DM2. Of the diabetic patients, 28 (34%) were depressed. Mean HbA1c for the diabetic plus depressed group was 7.5%, compared with 7.2% for the nondepressed diabetic group. The mean ages were similar (54 years vs. 55 years).
Although there were more men than women in both the depressed and nondepressed groups, there were no significant differences in their proportions across the glycemic control categories. All of the diabetic patients received education on glycemic control and have access to dieticians and diabetes nurse educators, Dr. Valdini noted.
Full data available on 26 patients in the depressed group show that 12 patients (46%) at the target HbA1c of <7%, whereas the nondepressed diabetics were at target in 31 of 52 (60%) cases, the authors reported. This difference was significant when tested with chi-squared statistics.