Sex Differences in Body Mass Index and Obesity in Chinese Patients With Chronic Schizophrenia

Sex differences in schizophrenia have been well recognized. However, sex differences in obesity associated with antipsychotics have received little systematic study. This study was conducted to compare sex difference effects of antipsychotics and related risk factors on obesity and body mass index (BMI) in Chinese patients with schizophrenia. A total of 204 inpatients with chronic schizophrenia (males/females = 140/66) were recruited. Demographic and clinical data were collected, and serum glucose and lipid levels were measured. The Positive and Negative Syndrome Scale (PANSS) was used to assess patients' psychopathology. The prevalence of obesity in female patients (21/66, 31.82%) was approximately 2 times that of male patients (22/140, 15.83%; P < 0.001) and women also had higher BMI than men (25.49 ± 4.42 kg/m versus 23.95 ± 3.67 kg/m; P < 0.005). Regression analyses showed that obesity was associated with type 2 diabetes (P < 0.05) and triglycerides (P < 0.05) in women, and limited to triglyceride in men (P < 0.01). Further correlation analysis showed that BMI was associated with the PANSS negative symptom subscore (P < 0.001) and the PANSS total score (P < 0.01) in men. In addition, women had higher low-density lipoprotein plasma levels than men. Our findings suggest that there are significant sex differences in bodyweight and obesity in chronic medicated patients with schizophrenia, with worse lipid metabolic dysfunction in female patients.