Aim of the study:
We investigated the association between obesity and body mass index (BMI) with Positive and Negative Syndrome Scale (PANSS) psychopathology, age at disease onset, and parameters linked to the metabolic syndrome (fasting plasma lipid and glucose levels), among antipsychotic-naïve first-episode schizophrenia (AN-FES) patients and nonadherent chronic schizophrenia individuals.

Subject or material and methods:
We recruited a total of 187 AN-FES patients or nonadherent chronic individuals for this study. Clinical and anthropometric data together with plasma lipid and glucose parameters were collected immediately after patients’ admission to the hospital. Patients were classified as obese with body mass index (BMI) ≥ 30, or as non-obese if overweight (BMI: 25 – 29.9) or of normal body weight (BMI: 18.5 – 24.9).

Results:
After controlling for the possible confounders we found that only BMI significantly predicted clinical and metabolic variables. Among AN-FES patients, higher BMI values predicted lower levels of HDL cholesterol (HDL-c), and higher ratios for LDL cholesterol (LDL-c)/HDL-c and triglyceride/HDL-c, while among nonadherent individuals, higher BMI values predicted higher number of psychotic episodes, and lower PANSS general psychopathology scores. The contribution of BMI ranged from approximately 5.8% to 29.6%, with the lowest contribution observed for number of psychotic episodes, and the highest contribution for the LDL-c/HDL-c ratio.

Discussion:
Our results indicate that AN-FES patients and nonadherent chronic patients differed in the effects of BMI.

Conclusions:
Higher BMI contributes to an increased risk for dyslipidemia among AN-FES patients and to the higher number of psychotic episodes, and less severe clinical psychopathology among nonadherent chronic schizophrenia individuals.