Risperidone-associated weight gain in children and adolescents: A retrospective chart review

Objective: Risperidone use has been associated with substantial weight gain in children and adolescents. Reports available to date have consisted of s mall case series evaluated without standardized indices of developmentally normative weight increase. The purpose of this study was to evaluate age- a nd gender-adjusted weight changes linked to risperidone use in a juvenile p sychiatric inpatient population. Method: Thirty-seven child and adolescent inpatients treated with risperido ne for 6 consecutive months were compared to a group of 33 psychiatric inpa tients with no atypical neuroleptic exposure. Weight, height, and body mass index (BMI) were recorded on at least a monthly basis, and Tanner staging was completed on admission. Percent change from baseline weight, changes in standardized z scores of weight for age and gender, and proportion of subj ects experiencing a greater than or equal to7% weight increase from baselin e were compared among groups. Results: Subjects in both groups were comparable at baseline except for gen der distribution (more males were in the risperidone group,p < 0.05). Rispe ridone-treated children and adolescents experienced significant weight gain between baseline and endpoint (paired t test, p < 0.001) that was first ev ident within 2 months of starting treatment, progressed steadily at an aver age rate of 1.2 kg/month, and did not reach a clear plateau during 6 months of observation. Significant increases in standardized weight were noted at 3 and 6 months for risperidone-treated subjects. Risperidone use conferred a substantial risk of gaining over 7% from baseline weight (odds ratio = 3 .5, 95% confidence interval = 1.8-6.6, p < 0.001). Conclusions: Six-month exposure to risperidone was associated with clinical ly significant weight gain in 78% of treated children and adolescents las o pposed to 24% of those in the comparison group, p < 0.001). Risperidone dos age, concomitant medication use, and other demographic characteristics such as age, pubertal status, gender, and baseline weight and BMI were not asso ciated with an increased risk of morbid weight gain. Standardized z scores offer advantages for the assessment of weight change among developing child ren and adolescents.