Effect of Comorbid Depression on Outcomes in Diabetes and Its Relationship to Quality of Care and Patient Adherence

Abstract

To determine whether current depression was associated with poorer quality of care and poorer patient adherence to treatment regimens and whether current depression was associated with patient diabetes outcomes independent of its relationships to quality of care and patient adherence among patients with diabetes. This study was conducted in the offices of family physicians who belong to the Statewide Primary Care Ambulatory Research and Resources Consortium from March 2006 to March 2011. Seven primary care physicians enrolled 10 to 20 English- or Spanish-speaking patients with diabetes presenting for routine follow-up visits. Subjects included 106 patients who completed a questionnaire documenting their depressive symptoms, compliance with diabetes therapy, diabetes-related quality of life, and patient satisfaction. The physicians completed a 4-item questionnaire concerning whether the patient had depression and any depression treatments that they ordered. All questions were answered either "yes" or "no." A practice research coordinator evaluated the quality of diabetes care provided and ordered hemoglobin A(1c) (HbA(1c)) testing for the patient. Depression was associated with poorer compliance, quality of care, diabetes-related quality of life, and patient satisfaction; only HbA(1c) levels did not correlate with depression. When adjusting for compliance and quality of care, depression was still associated with poorer quality of life and satisfaction (P ≤ .001). While physician recognition and treatment of depression were less than optimal, depression severity was a significant predictor of receiving some form of mental health intervention (P ≤ .05) except for the provision of mental health counseling. Poor diabetes control was associated with the provision of counseling (P ≤ .10), while poor quality of life was associated with recognition of depression (P ≤ .10). Depression was independently associated with satisfaction and quality of life but not diabetes control. Although depression severity was an important predictor of depression recognition and treatment, poor quality of life was a predictor of recognition, and poor diabetes control was a predictor of receiving mental health counseling.