Dextroamphetamine Treatment for Children With Hypothalamic Obesity

Abstract

Introduction: Hypothalamic obesity (HO) in children can be either genetic or acquired, as a result of a suprasellar tumor or its treatment. HO, resulting from hyperphagia and/or a decreased resting energy expenditure (REE), may have devastating consequences for the child and its family. Currently, no effective drug treatment is yet available for HO. Amphetamines – commonly used in children with attention-deficit/hyperactivity disorder – are known for their stimulant effect on REE and inhibitory effect on appetite. We here present our experiences of dextroamphetamine treatment in children and adolescents with acquired or genetic HO. Methods: A retrospective cohort evaluation was performed of patients (n = 18) treated with dextroamphetamine at 2 endocrine pediatric clinics. Off-label use of dextroamphetamine was initiated in patients with progressive therapy resistant acquired HO (n = 13) and in patients with genetic obesity (n = 5). Initial treatment dosing was once or twice daily 5mg. This dose was weekly increased with 5 mg/day depending on the patient’ wellbeing and the presence of side effects, to a maximum of 0.5 mg/kg/day. Anthropometrics and REE at start and during follow-up, changes in (hyperphagic) behavior, and side effects were assessed. Results: At start of treatment, mean age was 12.8 years ± 3.4 [range 7.1–17.9] and mean REE was 69.5%± 18.5 (n = 15). At follow-up, mean treatment duration was 18.3 months ± 14.7. Ten out of eighteen children (55.6%) showed clinically relevant weight loss. In 10/13 patients with acquired HO, weight loss was observed (mean ΔBMI SDS -1.09 ± 1.00), in one patient BMI stabilization (ΔBMI SDS +0.03), and in two patients an increase in BMI SDS was seen (mean ΔBMI SDS +0.32 ± 0.05). Of nine children with acquired HO and measurement of REE before and during treatment, a mean REE increase of +15.3% ± 10.5 was observed. In three out of five patients with genetic obesity, initially weight loss was observed resulting in BMI stabilization at end of follow-up due to weight regain (mean ΔBMI SDS -0.08 ± 0.19). In these patients, no difference in REE before and during treatment was observed. In two patients an increase in BMI SDS was seen (mean ΔBMI SDS +0.29 ± 0.25). However, one patient discontinued treatment after one month, due to hypertension. Thirteen out of 18 children (72.2%) reported improvement of either their hyperphagia, energy level, and/or behavior. No serious side effects were reported. Conclusion: In children and adolescents with acquired HO, treatment with dextroamphetamine may significantly lower BMI, reduce hyperphagia and improve activity level. In genetic HO, these effects were less pronounced. Future studies in a larger cohort and with randomized controlled designs are needed to support these results.