Changes in BMI, Waist-to-Hip Ratio in Never and Minimally Treated Patients With Psychosis

Investigators found differences in obesity measures in antipsychotic-naive and minimally treated patients with psychosis compared with healthy controls, according to the results of a meta-analysis published in Schizophrenia Research.

Investigators conducted a systematic search of the Medline, PsychINFO, and Embase databases to identify all English language publications examining obesity measures in patients with psychosis. Two investigators independently performed a search and assessed studies for eligibility; 2 additional investigators extracted data. Studies selected for inclusion reported antipsychotic exposure length and included a control group. As primary outcome measures, investigators abstracted body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) in antipsychotic-naive and minimally treated patients with psychosis and in healthy controls. Sociodemographic characteristics, psychiatric diagnoses, and illness severity were also extracted.

A total of 23 studies were eligible for meta-analysis; all 23 studies reported BMI, while just 9 and 5 reported WC and WHR, respectively. BMI was lower in antipsychotic-naïve and minimally treated patients with psychosis compared with healthy controls (standard mean difference [SMD], −0.19; 95% CI, −0.34 to −0.05; P =.009). High heterogeneity (I² = 65%) was observed between studies; a leave-out sensitivity test indicated that no single study contributed to this heterogeneity. Per a sensitivity analysis that matched patients with healthy controls by age, sex, and ethnicity, BMI was lower in the patient group compared with healthy controls (SMD, −0.26; 95% CI, −0.51 to −0.00; P =.05). No differences in WC were observed between antipsychotic-naïve and minimally treated patients with psychosis and healthy controls (SMD, −0.07; 95% CI, −0.17 to 0.32; P =.055). However, WHR was elevated in antipsychotic-naïve and minimally treated patients with psychosis compared with healthy controls (SMD, 0.34; 95% CI, 0.14 to 0.55; P =.001). In this analysis, heterogeneity was not significant.

These data do not support an inherent relationship between obesity and schizophrenia in the absence of an antipsychotic. The study results warrant further research to elucidate the relationship between body fat content and psychosis.

Reference

Shah P, Iwata Y, Caravaggio F. Alterations in body mass index and waist-to-hip ratio in never and minimally treated patients with psychosis: A systematic review and meta-analysis [published online January 23, 2019].  Schizophr Res. doi:10.1016/j.schres.2019.01.005