Question. I have a close friend whose husband is a brittle diabetic. In the last couple of years, he has lost interest in hobbies and activities that used to be enjoyable to him. He has violent outbursts without provocation. His father is bipolar. Are diabetics at higher risk for mood disorders and does this effect his blood sugar level? Are there certain chemical/neurotransmitters that are implicated in both mood disorders as well as diabetes? Are there medications that he can take that will not further destabilize his diabetes?
Answer. You may be interested in obtaining the article by Paul Goodnick et al in the Journal of Clinical Psychiatry, April 1995, on Treatment of Depression in Patients with Diabetes Mellitus. Goodnick et al discuss some data showing higher rates of depression in diabetic populations than in non-diabetic controls; evidence that depression may have a less favorable course in diabetic patients (e.g., higher relapse rate); and evidence that depression is associated with both hyperglycemia (high blood sugar) and increased complications of diabetes.
There does seem to be a neurochemical link between depression and diabetes, in that serotonin–a chemical in the brain that regulates mood–can affect blood sugar. Specifically, serotonin seems to reduce blood sugar, independent of insulin secretion. Antidepressants that boost serotonin (SSRIs such as Prozac and Zoloft) are therefore preferred to the older tricyclic antidepressants in depressed diabetics. The tricyclics can lead to elevated blood sugar. However, in the case of your friend’s husband, the issue of a bipolar disorder must be examined carefully, especially given the father’s history. This may be present independent of the diabetes, but could, in theory, be precipitated by fluctuations in blood sugar.
So as far as I know, the mood stabilizer valproate (Depakote) does not adversely affect diabetes. I would recommend referring this individual to a medical-school based mood disorders clinic, which could work closely with his general physician.