For the atypical antipsychotic agents, significant weight gain may occur, hampering compliance and causing adverse health effects. Few studies have investigated body composition changes with detailed methods.

To describe the effects over six months on body composition in schizophrenic patients randomized to treatment with sertindole or olanzapine.

Results from the first six patients enrolled in a 1y trial of consecutive patients (18-65y; Body Mass Index [BMI] ≤ 35 kg/m2) diagnosed with DSM-IV schizophrenia in the need of a second line antipsychotic agent. Weight, BMI, waist circumference (WC), %bodyfat (%BF) measured by 8-electrode bio-electrical impedance (BIA8) were assessed at each visit.

At baseline, moderately high median values were observed for weight (82.5kg), BMI (28.1), WC (100 cm) and %BF (25%). One subject was classified as normal weight, four as overweight and two as obese based on BMI, while four out of six were abdominally obese based on WC. Body composition values remained stable during the first month of treatment, but the median values had decreased slightly after six months (weight -0.5, BMI -0.2, waist circumference -2 cm, %BF 0%). The range was, however, fairly large for weight (-5.2 to 5.7kg), BMI (-1.7 to 1.7), WC (-5 to 7cm) and %BF (-4 to 3%).

Although there was individual heterogeneity in body composition development, the median changes were close to zero over six months of treatment with either olanzapine or sertindole. The small effects on body composition measured both by simple anthropometry and BIA8 are remarkable.