Change in obesity‐related metabolic abnormalities associated with BMI improvement through life‐style intervention: a meta‐regression

The reduction in body mass index standard deviation score (BMI-SDS) associated with improvement in biomarkers relating to metabolic health in obese children is unknown. We aimed to establish the change in BMI-SDS associated with improved inflammation, liver function, and insulin resistance to inform clinical guidelines for pediatric weight management interventions and to assess the efficacy of future trials. A large-scale systematic review was conducted to identify relevant studies. Studies of children with a diagnosis of obesity according to defined BMI thresholds, participating in lifestyle interventions to reduce obesity, were included. Studies must have reported baseline (pre-) and postintervention (or change of) BMI-SDS and either fasting glucose, homeostatic model of insulin resistance (HOMA-IR), alanine aminotransferase (ALT), C-reactive protein (CRP), or interleukin-6 (IL-6). A series of meta-regressions were conducted to establish links between BMI-SDS change scores and change in metabolic markers of health. Sixty-eight articles were identified. From the meta-regression analyses, across all study subsets, greater mean falls in all four parameters, (HOMA-IR, Glucose, ALT, and CRP) were observed with greater mean loss of BMI-SDS, but the trends were only statistically significant for HOMA-IR and CRP (P = .003; P = .021). However, we could not find minimum changes in BMI-SDS that would ensure a fall in these outcomes. At this time, we are unable to recommend a definitive value of BMI-SDS reduction needed to improve the markers of metabolic health. Future trials should aim to report additional indices of derived BMI values, which may better reflect changes in actual adiposity.