Predictive Factors of Low HDL-C in Patients with Schizophrenia

Schizophrenia patients engage in more sedentary life activities and endure a higher risk of metabolic syndrome than general population. Evidence on investigating the predictors in relation to low HDL-C in schizophrenia is still lacking.

This cross-sectional study recruited 133 schizophrenia patients from a tertiary hospital; 13 patients were not included (12 refused participation and 1 had missing data). Blood samples were collected to determine plasma levels of total cholesterol, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol. Atherogenic index of plasma was calculated using log10(TG/HDL-C). The physical capacity was measured by 6-minute walk test (6MWT). The group of low HDL-C was categorized according to the sex-specific HDL-C thresholds (male: < 40 mg/dL; female: < 50 mg/dL); the reference category was the group of normal HDL-C. Three logistic regression models were performed to identify if sex, hospitalization times, 6MWT distances and TG levels were the significant predictors of low HDL-C. We examined the model performances using the area under the receiver operating characteristics curve (AUC) and calculated accuracy, sensitivity and specificity. P value of FDR < 0.05 was considered statistically significant after correcting for multiple comparisons.

Model 1 (AUC = 0.79, accuracy/sensitivity/specificity = 0.73/0.60/0.81) and Model 2 (AUC = 0.82, accuracy/sensitivity/specificity = 0.75/0.66/0.81) controlled without or with education years. Model 3 (AUC = 0.82, accuracy/sensitivity/specificity = 0.76/0.64/0.84) controlled educational years, height and body mass index and showed relatively optimal accuracy and specificity with similar performance of Model 2. All models found that female, hospitalization times, 6MWT distances and TG levels were significant predictors associated with low HDL-C after multiple comparisons (all p < 0.05).

The results provide the clinical importance to assess low HDL-C, especially for female schizophrenia with more hospitalization, shorter 6MWT distances or higher TG levels due to increased susceptibility to cardiometabolic risks.