Weight gain in adolescents treated with risperidone and conventional antipsychotics over six months

Weight gain is a serious side effect of antipsychotic therapy. Potential co nsequences of obesity include noncompliance with medications as well as sig nificant morbidity and mortality. Because atypical antipsychotic agents are increasingly being used in adolescents, it is important to determine and f urther characterize the rate of weight gain in this population. This study compares weight gain associated with the use of conventional antipsychotic agents with that seen with risperidone in adolescents. This retrospective s tudy identified 60 adolescent inpatients who were taking risperidone (n = 1 8), conventional neuroleptics (n = 23), or no antipsychotic medication (n = 19). Monthly height and weight measurements were recorded over a 6-month p eriod, allowing body mass index (BMI) values to be calculated. Subjects tre ated with risperidone gained a mean of 8.64 kg and increased in body mass b y 3.67 kg/m(2) over the 6-month observation period. Those taking convention al antipsychotics gained 3.03 kg or 0.31 kg/m(2) in body mass, whereas the control group actually lost weight (-1.04 kg, or -1.01 kg/m(2)) in the same time frame. Although both antipsychotic groups gained in weight and BMI, t he risperidone-treated group gained significantly more body mass than did t he conventional antipsychotic group (p = 0.0011). Gains in body weight did not correlate with dose, and concomitant medications such as stimulants and lithium did not contribute to changes in BMI.