Is obstructive sleep apnea the missing link between metabolic syndrome and second-generation antipsychotics: Preliminary study

BACKGROUND: Metabolic syndrome in individuals taking second-generation antipsychotics is thought to be mediated by antipsychotic-induced weight gain. However, recent literature challenges this notion, and theoretically, it may also be mediated through obstructive sleep apnea (OSA). This study explores the contribution of OSA in antipsychotic-induced metabolic syndrome. MATERIALS AND METHODS: Forty-three participants suffering from schizophrenia spectrum disorder and major depressive disorder, taking second-generation antipsychotics were included in this study. Treatment history was taken in detail, and lifetime exposure to antipsychotics was converted to olanzapine-equivalent doses. Physical characteristics were noted. OSA was screened through the Hindi version of Berlin Questionnaire. Plasma glucose, serum total cholesterol, serum high-density lipoprotein, and serum triglyceride were measured after 12-h fasting. Adult treatment Panel-III criteria were used to diagnose metabolic syndrome. RESULTS: Gender distribution was comparable in the study sample. About 27% had continuous illness, 25.6% of participants had metabolic syndrome, and 20.9% were at high risk for sleep apnea. Participants with and without metabolic syndrome were comparable with regard to demographic variables, duration of illness, and lifetime exposure to antipsychotics. Logistic regression depicted that OSA (odds ratio [OR] = 15.09), waist circumference (OR = 1.15), and fasting plasma glucose (OR = 1.21) increased the risk of metabolic syndrome. CONCLUSION: Results of the present study suggest that metabolic syndrome in participants taking second-generation antipsychotics is mediated through OSA.