Preclinical signs of liver and cardiac damage in youth with metabolically healthy obese phenotype

BACKGROUND AND AIMS: We aimed to evaluate whether the metabolically healthy obese (MHO) phenotype was associated with hepatic steatosis (HS) or left ventricular hypertrophy (LVH) in young people with overweight (OW), obesity (OB) and morbid obesity (MOB) and whether the prevalence of these comorbidities was affected by OB severity. METHODS AND RESULTS: An abdominal ultrasound was performed in 1769 children and adolescents, mean age 10.6 years (range 5-18) with MHO phenotype, defined as the absence of traditional cardiometabolic risk factors, in order to identify HS. In a subsample of 177 youth the presence of LVH, defined by 95th percentile of LV mass/h2.7 for age and gender, was also analyzed. The prevalence of HS increased from 23.0% in OW to 27.8% in OB and 45.1% in MOB (P < 0.0001). The proportion of LVH increased from 36.8% in OW to 57.9% in OB and 54.5% in MOB (P < 0.05). As compared with OW, the odds ratio (95% CI) for HS was 2.18 (1.56-3.05), P < 0.0001) in OB and 6.20 (4.26-9.03), P < 0.0001) in MOB, independently of confounding factors. The odds ratio for LVH was 2.46 (1.20-5.06), P < 0.025) in OB and 2.79 (1.18-6.61), P < 0.025) in MOB, as compared with OW. CONCLUSION: In spite of the absence of traditional cardiometabolic risk factors, the prevalence of HS and LVH progressively increased across BMI categories. MHO phenotype does not represent a "benign" condition in youth.