Strong effect of pubertal status on metabolic health in obese children: a longitudinal study.

CONTEXT: The concept of metabolic healthy obese (MHO) status has been proposed also for children. However, it is unclear whether this is a stable status in childhood.

OBJECTIVE: The aim was to analyze the changes of MHO status over time.

DESIGN AND SETTING: This is 1-year longitudinal analysis of our obesity cohort.

PARTICIPANTS: All obese children of our outpatient obesity clinic with 1-year follow-up were included.

INTERVENTIONS: Standard care intervention was used.

MAIN OUTCOME MEASURES: We examined body mass index (BMI), waist circumference, pubertal stage, blood pressure, fasting lipids, glucose, and insulin resistance index homeostasis model assessment (HOMA). MHO status was defined by absence of cardiovascular risk factors.

RESULTS: A total of 2017 obese children (mean age, 11.6 ± 2.8 y; 45% male; BMI, 28.5 ± 5.3 kg/m(2); BMI-z score, 2.4 ±0.5) were enrolled onto the study, and 49.3% of the children were MHO at baseline. After 1 year, the majority of the MHO remained MHO (68.0%). MHO children were significantly younger, more frequently prepubertal, and less overweight compared with metabolic unhealthy obese (MUO) children (all P < .05). In the longitudinal analyses, entering into puberty (OR, 1.9; 95% confidence interval, 1.3-2.8]; P = .004) doubled the risk for switching from MHO to MUO, whereas changing from mid to late puberty nearly tripled the likelihood for switching from MUO to MHO (OR 3.1 [2.1-4.5], P < .001) in multiple logistic regression analyses adjusted for age, sex, and changes of body mass index standard deviation score (BMI-SDS).

CONCLUSIONS: MHO is a stable status in childhood obesity as long as pubertal status remains stable. Due to the strong association between puberty and MUO status, the concept of MHO is questionable, at least in pubertal children.