Associations between body mass index in different childhood age periods and hyperuricemia in young adulthood: the China Health and Nutrition Survey cohort study

Uric acid reference values for children and adolescents should be stratified by pubertal stage

BACKGROUND AND AIM

To establish reference values for hyperuricemia (HUA) in children and adolescents.

METHODS AND RESULTS

The study enrolled 4807 students from "The Evaluation and Monitoring on School-based Nutrition and Growth in Shenzhen study." Utilizing quantile regression, associations between age, body mass index (BMI), pubertal stage, and serum uric acid (SUA) were examined, alongside the relationship between SUA and cardiovascular disease (CVD) risk factors. Reference values for SUA were explored using receiver operating characteristic analysis, considering sex and pubertal stage. The prevalence of HUA was 34.3 % for boys and 29 % for girls (using the adult HUA diagnostic criteria: >420 μmol/L for males, >360 μmol/L for females), increasing with higher BMI, age, and pubertal stage. Pubertal stage had the largest influence on SUA in boys, while nutritional status was the most significant factor affecting SUA in girls. Adjusting for age and pubertal stage, higher SUA levels correlated with an increased risk of CVD risk factors. Proposed reference values included >360 μmol/L for girls ages 6-17 years and prepubertal boys. For pubertal boys, reference values varied based on age: >392 μmol/L for ages 9-11 in early-middle puberty, >429 μmol/L for ages 12-14 in early-middle puberty, >478 μmol/L for ages 12-14 in late puberty, and >505 μmol/L for ages 15-17 in late puberty.

CONCLUSIONS

Stratifying HUA reference values by pubertal stage, particularly for boys, is crucial. Long-term follow-up of individuals with high SUA levels may aid in refining SUA reference values.

A Gender-, Age-, and Weight Status-Specific Analysis of the High Prevalence of Hyperuricemia Among Chinese Children and Adolescents with Obesity

Objective

To explore the gender-, age-, and weight status-specific prevalence of hyperuricemia (HUA) and its associated risk factors among Chinese children and adolescents with obesity.

Methods

A total of 1329 children aged 2-17 years, who were diagnosed with obesity and hospitalized in our center from January 2016 to December 2022 were recruited. They were divided into mild obesity, moderate obesity, and severe obesity groups. HUA was defined as fasting serum uric acid level >420 μmol/L for boys and >360 μmol/L for girls. Multivariate logistic regression analyses were performed to identify risk factors for HUA.

Results

The highest proportion of hospitalized obese children was aged 10-13 years comprising 677 (50.9%) followed by those aged 6-9 years comprising 348 (26.2%) whereas the least proportion was aged 2-5 years comprising 76 (5.7%). The above differences in age distribution were still present in subgroup analyses according to weight status. Most hospitalized obese children were boys (64.7%), especially in the severe obesity group (75.0%). The overall estimated prevalence of HUA in obese children was 54.8%. It presented a gradual increase trend over the last 7 years, with more rapidly in boys than in girls. Subgroup analysis by weight status showed that the prevalence of HUA was higher in children with moderate obesity (64.3%) and severe obesity (64.2%) when compared with mild obesity (48.2%) (P all<0.01). Boys reached a relatively high HUA incidence level (≥60%) at age 12, which occurred about 2 years later than in girls (age 10). With 12 years as the cut-off point, a high prevalence of HUA (≥60%) was observed in both genders. Multivariable logistic regression analyses showed that boy (OR=2.844, 95% CI 2.024-3.998), age (OR=1.253, 95% CI 1.155-1.360), BMI-Z score (OR=2.132, 95% CI 1.438-3.162), fasting blood glucose (OR=0.907, 95% CI 0.860-0.956), phosphorus (OR=4.123, 95% CI 2.349-7.239), alkaline phosphatase (OR=1.002, 95% CI 1.001-1.004), creatinine (OR=1.067, 95% CI 1.037-1.098), urea nitrogen (OR=1.193, 95% CI 1.032-1.378), aspartate aminotransferase (OR=1.016, 95% CI 1.002-1.030), triglycerides (OR=1.339, 95% CI 1.075-1.667), and high-density lipoprotein cholesterol (OR=0.381, 95% CI 0.160-0.910) were independently associated with odds of HUA (P all<0.05).

Conclusion

The prevalence of HUA in Chinese obese children and adolescents is unexpectedly high. Childhood HUA was significantly associated with obesity. Gender and age differences were observed in the association between childhood obesity and HUA. Obese children aged ≥12 years should be focused on screening the risk of HUA.

BMI at different childhood age periods associated with cardiometabolic disorders in young adulthood

OBJECTIVE

The aim of this study was to investigate when the association between childhood obesity and adult cardiometabolic disorders starts to be operative.

METHODS

The study cohort included 811 participants who had data on blood pressure, lipid profile, fasting blood glucose, fasting insulin, or alanine aminotransferase in adulthood and had at least one measurement of BMI in childhood.

RESULTS

Childhood BMI z score was significantly associated with increased risks of ≥1 cardiometabolic disorders, ≥2 cardiometabolic disorders, and elevated blood pressure in adulthood for age groups of 6 to 9 years, 10 to 12 years, 13 to 15 years, and 16 to 18 years, after adjustment for covariates. For low high-density lipoprotein cholesterol, significant associations were observed for age groups of 10 to 12 years, 13 to 15 years, and 16 to 18 years. For elevated triglyceride and elevated alanine aminotransferase, significant associations were observed for age groups of 13 to 15 years and 16 to 18 years. For insulin resistance, significant associations were observed for age groups of 10 to 12 years and 16 to 18 years. For elevated total cholesterol, elevated low-density lipoprotein cholesterol, or elevated fasting blood glucose, no association was observed in any age group.

CONCLUSIONS

The association between childhood BMI and adult cardiometabolic disorders begins to be operative from early life. These results support universal screening of childhood obesity starting at an early age.