P2B305: Impact of Anti-obesity Medications in Children with Complex Medical Conditions Associated with Hyperphagia

Background: Children with complex medical needs represent a disparate proportion of children who are obese. Many of these conditions, or the medications that treat them, cause hyperphagia and refractory obesity. Understanding how these children respond to anti-obesity medication is an important contribution to a current gap in the pediatric obesity literature. Our objective was to describe the response of 38 patients with hyperphagia-associated medical conditions to the interventions of diet and physical activity intervention alone, vs. diet and physical activity intervention plus anti-obesity medications.

Methods: Using electronic medical records, we searched patients ages 4-21 enrolled in a multidisciplinary pediatric obesity center from January 1, 2017 to June 14, 2022 for the following diagnoses: autism, chromosomal abnormalities, drug-induced obesity, food deprivation and hypothalamic obesity. We then studied those who had received a period of dietary intervention (DI) and physical activity intervention (PAI) only, followed by a period of dietary, physical activity intervention plus anti-obesity medication (AOM). Medications included oral phentermine, topiramate or Vyvanse. Patients were disqualified if they did not receive DI and PAI before starting medication; if they did not return for follow-up on medication; or if they had a gap in care for longer than 12 months.

Results: 75 patients had a qualifying diagnosis; 38 patients met the criteria for DI and PAI alone followed by DI, PAI and an AOM. During the period of DI and PAI alone, the mean BMI percentile increased by 1.22%. During the DI and PAI plus AOM period, the mean BMI percentile decreased by 4.12% (p = 0.0787) and the median BMI percentile decreased by 1% (p=0.0647); see figure 1. Diagnostic subgroups were autism (19), chromosomal abnormalities (6), drug-induced obesity (4), hypothalamic obesity (4), food deprivation (3); these numbers were too small for comparisons.

Conclusion: Children with hyperphagia-associated medical conditions are refractory to successful treatment. The decrease in BMI percentile in our medication treatment group did not quite meet statistical significance, likely due to a small n-number. Using the patients as their own control, the mean BMI percentile increased prior to beginning medications, as is generally the case in these refractory groups of children. Further analysis of the diagnostic subgroups may have gleaned important information had we had higher numbers. This is the first descriptive data in these subgroups of children, and our aim is that our work is the impetus for others to perform further analysis.