Percentiles of serum uric acid and cardiometabolic abnormalities in obese Italian children and adolescents

Background: To investigate the association of serum uric acid (SUA) with cardiometabolic abnormalities in Caucasian overweight/obese children (<10 years of age) versus adolescents (>= 10 years of age) by drawing age and gender specific percentiles of uric acid. Methods: Cross-sectional evaluation of 1364 Caucasian overweight/obese patients (age 4.1-17.9 years; 726 males, 53%; 560 children, 41%). Results: SUA levels were significantly lower in children than in adolescents (4.74 +/- 1.05 vs. 5.52 +/- 1.49 mg/dl, p < 0.001) and peaked in 12-14 years-old boys and 10-12 years-old girls. In children with levels of SUA in the highest quartile (N = 75, 13%), OR for high triglycerides was 4.145, 95% Cl 1. 506-11.407 (p = 0.009). In adolescents with SUA in the highest quartile (N = 274, 34%), ORs for insulin resistance was 2.399 (95% Cl 1.4-4.113; p < 0.001); for impaired fasting glucose 2.184 (95% Cl 0.877-5.441; p = 0.07); for impaired glucose tolerance 2.390 (95% Cl 1.405-4.063; p = 0.001); and for high triglycerides 1.8, (95% Cl 0.950-3.420; p = 0.05). Multivariable random-effect linear regression models demonstrated that waist circumference and age (p < 0.0001 for both) are the variables most significantly predicting SUA levels, followed by triglycerides (p = 0.005) and 2 h glucose (p = 0.03) while HOMA-IR and BMI z-score did not predict SUA. Conclusions: High uric acid is associated with metabolic abnormalities and particularly with waist circumference very early in childhood.