Diabetes mellitus (DM) is considered one of the most psychologically and behaviorally demanding chronic medical conditions. Patients with DM and serious mental illness (SMI), including schizophrenia, schizoaffective disorder, major depressive disorder (MDD), and bipolar disorder, are more likely to have poor adherence to medications as well as poor adherence to diet and lifestyle recommendations, which can lead to poor glycemic control, decreased quality of life, and increased health care expenses.1-4 Up to 27% of patients with DM have a depression diagnosis, and up to 60% of patients with DM experience depressive symptoms.5 Additionally, 1 in 4 patients with schizophrenia have a DM diagnosis.6 Serious mental illness can compromise DM self-management and glycemic control, which increases the risk of DM-related complications.7
These factors combine to make DM self-management essential for optimal glycemic control and prevention of DM-related complications. The American Diabetes Association recommends coordinated management of DM and SMI to achieve DM treatment targets.8 Interventions involving collaborative care teams have assisted in managing patients with concurrent SMI and DM. Collaborative interventions have reduced all-cause mortality, increased the number of patients reaching hemoglobin A1c (HbA1c) targets, increased overall improvement in HbA1c, increased rates of depression remission, and increased medication adherence.9-12
Background
Collaborative interventions have improved glycemic control in patients with concurrent SMI and DM. A study by Desai and colleagues examined the relationship between psychiatric disorders and the quality of DM care in a national sample of veterans.7 Data were collected using chart-abstracted quality data from administrative database records for a sample of veterans with DM who had at least 3 outpatient visits in the previous year (n = 38,020). About 25% of the sample had a diagnosed psychiatric disorder, 91.5% of veterans completed an HbA1c test, and most veterans with a psychiatric disorder completed the 5 quality indicators for DM care (foot inspection, HbA1c determination, pedal pulses examination, foot sensory examination, and retina examination). Veterans with psychiatric disorders did not have a poorer quality of care for secondary prevention of DM compared with that of other veterans.7
In the PROSPECT study (Prevention of Suicide in Primary Care Elderly: Collaborative Trial), a primary care-based depression management program assessed a collaborative intervention to improve care in patients with depression and DM.9 Fifteen depression care managers, including trained social workers, registered nurses (RNs), and psychologists, collaborated with primary care physicians (PCPs) to assist in recognizing depression, offer guideline-based treatment recommendations, and provide algorithm-based care, monitoring, and follow-up. After a median follow-up of 52 months, patients with depression and DM in the intervention group were less likely to die during the 5-year follow-up period compared with those in usual care (adjusted hazard ratio, 0.49 [95% confidence interval (CI), 0.24-0.98]). The study authors concluded that integrated depression care management significantly reduced all-cause mortality in patients with depression and DM.9
A single-blind, randomized, controlled trial conducted by Katon and colleagues examined patients with poorly controlled DM, coronary artery disease (CAD), or both, and concurrent depression in 14 primary care clinics (n = 214).10 The intervention consisted of nurse care managers who were trained RNs with experience in DM education and supervised by PCPs, providing guideline-based, collaborative care over 12 months to improve glycemic control, blood pressure (BP), and lipid control. The nurse care managers followed up with patients every 2 to3 weeks at office visits, and the intervention was compared with usual care by a physician. At 12 months, patients in the intervention group had significant improvement in HbA1c, low-density lipoprotein cholesterol, systolic BP, and depression compared with that of those under usual care. At 12 months, the HbA1c in the patients in the intervention group was significantly improved with an overall percentage change of 0.81 compared with 0.23 in the usual care group (estimated between-group difference, -0.56 [95% CI, -0.85 to -0.27]). The study authors concluded that integrated management and proactive follow-up of medical and psychological illnesses improved both medical outcomes and depression in patients with DM, CAD, or both.10
Another study by Bogner and colleagues investigated an integrated care intervention for patients with depression and DM to improve adherence to antidepressant and antidiabetic medications, glycemic control, and depression remission.11 Two trained research coordinators (a bachelor’s level and a master’s level) administered all intervention activities. The integrated care managers collaborated with physicians, offering education and guideline-based treatment recommendations to patients to monitor medication adherence and clinical status. The intervention supplemented regular primary care follow-up visits and was compared with usual care. At 12 weeks, patients in the integrated care group were more likely to achieve an HbA1c < 7% (60.9% vs 35.7%; P < .001) and remission of depression (58.7% vs 30.7%; P < .001) compared with those in usual care. There also was a significant improvement in adherence to DM and antidepressant medications in the intervention group compared with those in usual care during the study period.11
A systematic review and meta-analysis by Huang and colleagues assessed randomized controlled trials of collaborative care for diabetic patients with depression.12 Trials that reported depression treatment response, depression remission, HbA1c values, and adherence to antidepressant and/or hypoglycemic medications were included. A total of 8 trials randomized 2,238 patients with concurrent depression and DM and compared collaborative care with usual care. Collaborative care was associated with a significant increase in depression treatment response, reduction in HbA1c, and significant improvement in adherence rates for antidepressant and hypoglycemic medications compared with that of usual care. A reduction in HbA1c favored the collaborative care group; however, this reduction was not significant (mean difference, -0.13 [95% CI, -0.46 to 0.19]; P = .08 for heterogeneity; I2 = 51%). The study authors concluded that a collaborative care model significantly improved depression outcomes and adherence to medications in patients with concurrent DM and depression and recommended continued collaborative care for this population.12