Feasibility, safety, and efficacy of dietary or lifestyle interventions for hypothalamic obesity: A systematic review.

BACKGROUND & AIMS: A dysfunctional hypothalamus may result in decreased feelings of satiety (hyperphagia), decreased energy expenditure, and increased fat storage as a consequence of hyperinsulinemia. Hypothalamic dysfunction may thus lead to morbid obesity and can be encountered in childhood as a consequence of congenital, genetic, or acquired disorders. There is currently no effective treatment for hypothalamic obesity (HO). However, comparable to alimentary obesity, dietary and lifestyle interventions may be considered the cornerstones of obesity treatment. We questioned the effect of dietary or lifestyle interventions for HO and systematically searched the literature for evidence on feasibility, safety, or efficacy of dietary or lifestyle interventions for childhood hypothalamic overweight or obesity.

METHODS

A systematic search was conducted in MEDLINE (including Cochrane Library), EMBASE, and CINAHL (May 2023). Studies assessing feasibility, safety, or efficacy of any dietary or lifestyle intervention in children with hypothalamic overweight or obesity, were included. Animal studies, studies on non-diet interventions, and studies with no full text available were excluded. Because the number of studies to be included was low, the search was repeated for adults with hypothalamic overweight or obesity. Risk of bias was assessed with an adapted Cochrane Risk of Bias Tool. Level of evidence was assessed using the GRADE system. Descriptive data were described, as pooled-data analysis was not possible due to heterogeneity of included studies.

RESULTS

In total, twelve studies were included, with a total number of 118 patients (age 1-19 years) of whom one with craniopharyngioma, one with ROHHAD-NET syndrome, 50 with monogenic obesity, and 66 with Prader-Willi syndrome (PWS). Four studies reported a dietary intervention as feasible. However, parents did experience difficulties with children still stealing food, and especially lowering carbohydrates was considered to be challenging. Seven studies reported on efficacy of a dietary intervention: a well-balanced restrictive caloric diet (30% fat, 45% carbohydrates, and 25% protein) and various hypocaloric diets (8-10 kcal/cm/day) were considered effective in terms of weight stabilization or decrease. No negative effect on linear growth was reported. Four studies reported on specific lifestyle interventions, of which three also included a dietary intervention. Combined dietary and lifestyle intervention resulted in decreased BMI, although BMI returned to baseline values on long-term. One additional study was identified in adults after brain trauma and showed a significant reduction in BMI in one out of eight patients after a combined dietary and lifestyle intervention.

CONCLUSIONS

Hypocaloric diet or restrictive macronutrient diet with lower percentage of carbohydrates seems feasible and effective for childhood HO, although most of the studies had a high risk of bias, small cohorts without control groups, and were conducted in children with PWS only, compromising the generalizability. Lifestyle interventions only resulted in BMI decrease in short-term, indicating that additional guidance is needed to sustain its effect in the long-term. Literature on feasibility and efficacy of a dietary or lifestyle intervention for hypothalamic overweight or obesity is scarce, especially in children with acquired HO (following treatment for a suprasellar tumor). There is need for prospective (controlled) studies to determine which dietary and lifestyle intervention are most helpful for this specific patient group.