Independence of diabetes and obesity in adults with serious mental illness: Findings from a large urban public hospital.

OBJECTIVE: There is limited research on metabolic abnormalities in psychotropic-naïve patients with serious mental illness (SMI). Our study examined metabolic conditions in a large, ethnically diverse sample of psychotropic-naïve and non-naïve adults with SMI at an urban public hospital.

METHODS: In this cross-sectional study of 923 subjects, the prevalences of hyperglycemia meeting criteria for type 2 diabetes mellitus (T2DM) based on fasting plasma glucose and obesity defined by BMI and abdominal girth were compared across duration of psychotropic medication exposure. Multiple logistic regression models used hyperglycemia and obesity as dependent variables and age, sex, race/ethnicity, and years on psychotropics as independent variables.

RESULTS: Psychotropic-naïve patients, including both schizophrenia and non-psychotic subgroups, showed an elevated prevalence of hyperglycemia meeting criteria for T2DM and a decreased prevalence of obesity compared to the general population. Obesity rates significantly increased for those on psychotropic medications more than 5 years, particularly for patients without psychosis (BMI: aOR = 5.23 CI = 1.44-19.07; abdominal girth: aOR = 6.40 CI = 1.98-20.69). Women had a significantly higher obesity rate than men (BMI: aOR = 1.63 CI = 1.17-2.28; abdominal girth: aOR = 3.86 CI = 2.75-5.44). Asians had twice the prevalence of hyperglycemia as whites (aOR = 2.29 CI = 1.43-3.67), despite having significantly less obesity (BMI: aOR = .39 CI = .20-.76; abdominal girth: aOR = .34 CI = .20-.60). Hispanics had a higher rate of obesity by BMI than whites (aOR = 1.91 CI = 1.22-2.99).

CONCLUSIONS: This study showed disparities between obesity and T2DM in psychotropic-naïve patients with SMI, suggesting separate risk pathways for these two metabolic conditions.