Sex differences in the prevalence and clinical correlates of diabetes in Chinese patients with chronic schizophrenia

Sex differences have been noted in schizophrenia (SCZ) and diabetes mellitus (DM); however, the effect of sex on SCZ patients with DM remains unknown. We aimed to investigate sex differences in the prevalence, demographic and clinical correlates of DM in Chinese patients with chronic SCZ. A total of 988 Han Chinese SCZ patients (male/female: 638/350) were recruited from two psychiatric hospitals in China. We used the Positive and Negative Syndrome Scale (PANSS) to evaluate the psychopathological symptoms of the patients. In addition, serum glucose and lipid levels were assayed. The prevalence of DM in female patients (57/350, 16.29%) was higher than that in male patients (79/638, 12.38%). Binary logistic regression analyses confirmed that the prevalence of DM in female patients was higher than that in male patients (P < 0.001, OR = 4.62, 95% CI = 2.11-10.11). Moreover, female patients had significantly higher positive symptoms than male patients (P = 0.003, OR = 1.08, 95% CI = 1.03-1.14). Further, higher body mass index (BMI) and higher triglyceride (TG) were significantly associated with DM in men (both P < 0.05). Decreased high density lipoprotein (HDL) was significantly associated with DM in both male and female patients (both P < 0.01). Comorbid DM is more common in female SCZ patients, and there are sex-specific correlates of DM in SCZ.