This study will evaluate the effectiveness of cognitive behavioral therapy (CBT) in treating people with depression and type 2 diabetes.

Depression is a serious illness that affects a person's mood, thoughts, and physical being. Common symptoms of depression include persistent feelings of anxiety, guilt, or hopelessness; irregular sleep and appetite patterns; lethargy; disinterest in previously enjoyed activities; excessive irritability and restlessness; suicidal thoughts; and inability to concentrate. Depression is highly comorbid, often occurring in the presence of one or more other disorders. Up to 15% to 20% of the time, people with diabetes are also depressed. Diabetes is a disease that interferes with the body's proper production and use of the hormone insulin, which is needed to convert food into the energy required to perform daily life activities. Self-care is a crucial component of diabetes treatment. However, symptoms of depression can interfere with behaviors necessary to carry out this care. Cognitive behavioral therapy (CBT) has shown success in treating people with depression, but the effect of CBT on self-care behaviors and depression of those with diabetes is not well known. This study will evaluate the effectiveness of CBT for medical adherence and depression (CBT-AD) in people with a depressive mood disorder and type 2 diabetes.

Upon study entry, all participants will complete various assessments, including a psychiatric diagnostic interview, a series of paper questionnaires, neuropsychological testing, blood sample analysis, and blood sugar monitoring. Next, all participants will meet with a nutritionist and a nurse diabetes educator. The nutritionist will help set goals for eating, physical activity, weight, and blood glucose. The nurse diabetes educator will review diabetes medication history and blood glucose self-monitoring equipment.

Participants will then be randomly placed in one of two counseling groups. One group will meet for a single session that will be devoted to diabetes medical adherence. The other group will attend 10 to12 individual CBT sessions for diabetes medical adherence and depression management. The CBT sessions will last 45 to 50 minutes and will require practice of coping skills outside the sessions. Participants receiving CBT will also complete weekly assessments of depression, self-care, and diabetes medical adherence. All participants will be asked to monitor a prescribed medication with a pill cap for 4 months during treatment. At Month 2, participants in both groups will also meet again with the nutritionist to review original goals and adjust them as necessary. Most of the previous study assessments will be repeated at Months 4, 8, and 12. The neuropsychological testing will be repeated only at Month 12.

• Diabetes Mellitus
• Depression

• Behavioral: Enhanced treatment as usual plus adherence training
• Behavioral: Enhanced treatment as usual plus CBT-AD

• Active Comparator: Enhanced treatment as usual plus single-session life-steps treatment
• Experimental: Enhanced treatment as usual plus multiple-session CBT treatment (CBT-AD)

Inclusion Criteria:

• Diagnosis of type 2 diabetes that is poorly controlled despite treatment with an oral hypoglycemic, insulin, or both
• Diagnosis of major depression or dysthymia, or current subclinical symptoms of depression in spite of prescription of an antidepressant
• If on an antidepressant, oral hypoglycemic medication, or insulin, must have been on a stable dose for the preceding two months

Exclusion Criteria:

• Active untreated major mental illness (e.g., untreated psychosis), bipolar disorder, eating disorder, mental retardation, or dementia
• Experiencing suicidal thoughts
• History of or currently receiving CBT for depression
• Uses an insulin pump