The largest study of diabetes and depression to date has found a definite link between insulin regimens and depression on poor diabetes control. The Duke University Medical Center study of 1034 diabetic patients (18 years or older) also showed that patients who have to administer at least 3 insulin shots daily have a higher risk of having poor control over their disease, compared with patients who require less or no insulin.
Although depression affects diabetes control only in some patients, the researchers suggested that patients who need more insulin pay close attention to symptoms of depression. Research has indicated that 30% of adults with diabetes report having major depressive symptoms. Depressive symptoms in these patients range from reduced quality of life to increased diabetic complications.