Comparative analyses of surrogates of metabolic syndrome in children and adolescents with metabolically healthy obesity vs. metabolically unhealthy obesity according to Damanhoury's criteria.

OBJECTIVES: Metabolically healthy obesity (MHO) has been reported with varying frequencies in children. The reasons of metabolically healthy phenotype in some obese subjects are unclear. Our aim was to identify the frequency of MHO in obese subjects, to assess the potential associations of demographic characteristics, serum uric acid, alanine transaminase (ALT), pediatric nonalcoholic fatty liver disease fibsosis score probability (PNFS p) with MHO status and to evaluate the differences between MHO and metabolically unhealthy obesity (MUO) with regard to metabolic syndrome surrogates.

METHODS: 251 consecutive obese subjects (125 females) aged 7-18 years were included. Subjects were classified as having MHO according to Damanhoury's criteria. Several metabolic variables were measured, PNFS p was calculated by using the formula: z=1.1+(0.34*sqrt(ALT))+ (0.002*ALP)-(1.1*log(platelets)-(0.02*GGT).

RESULTS: Median age of the subjects was 12.5 yr (range: 7.0-17.0 yr). The frequency of MHO was 41 %. Subjects with MHO were significantly younger, had lower waist circumference (WC) and waist height ratio (WHtR) and lower HOMA-IR than those without MHO(p<0.05 for all). Frequencies of hyperuricemia, hypertransaminasemia, hepatosteatosis and PNFS p values≥8 were similar betwen the groups. When putatively influential factors associated with MHO status were assessed with logistic regression analysis, only WC(β=1.03) and HOMA-IR(β=1.166) emerged as significant factors(Nagelkerke R2=0.142). None of the investigated demographic factors were associated with MHO status.

CONCLUSIONS: We found a remarkably high frequency of MHO status. Nevertheless, the absence of decreased frequencies of hyperuricemia, hypertransaminasemia and PNFS in subjects with MHO may suggest the need to reconsider the validity of the criteria defining MHO.