Predictors of mortality in patients with serious mental illness and co-occurring type 2 diabetes

Persons with serious mental illness (SMI) have higher rates of chronic medical conditions such as type 2 diabetes and mortality than the general population. We assessed demographic and health related factors in the prediction of all-cause mortality among SMI patients with diabetes and a comparison group of diabetic patients without SMI. From 1999 to 2002, 201 patients with type 2 diabetes and SMI were recruited from community mental health centers and 99 persons with type 2 diabetes and no identified mental illness were recruited from nearby primary clinics. Deaths over an average seven-year period after baseline assessment were identified using the Social Security Administration's Death Master File. Twenty-one percent in each group died over follow-up. Age, smoking status, duration of diabetes, and diabetes-related hospitalization in the 6 months prior to baseline assessment predicted mortality in all patients. Among the non-SMI patients, those who were prescribed insulin had over a four-fold greater odds of mortality whereas this association was not found in the SMI patients. Diabetes likely contributes to mortality in persons with SMI. Providers need to be especially vigilant regarding mortality risk when patients require hospitalization for diabetes and as their patients age. Smoking cessation should also be aggressively promoted.