Intensified association between waist circumference and hypertension in abdominally overweight children

Background Abdominal adiposity is an important risk factor for childhood hypertension. The present study aimed to compare the strength of the association between waist circumference (WC) and hypertension in children with different WC levels. Methods A total of 82,413 Chinese children aged 9-17 years were selected. An abdominally overweight child was defined as a child with WC ≥75th sex- and age-specific percentile. Hypertension was categorised as ≥95th sex-, age- and height-specific percentile. Logistic regression model was applied to calculate the odds ratio (OR) and 95% confidence interval (CI) of WC for hypertension after WC was transformed into sex- and age-specific z-score. Results Abdominally overweight children presented a higher risk of hypertension (OR: 2.39; 95% CI: 2.26, 2.54) than children with normal WC. In children with normal WC, one sex- and age-specific standard deviation increase in WC was associated with a 42% increase in odds of hypertension (OR: 1.42; 95% CI: 1.30, 1.55). That increase was elevated to 74% in abdominally overweight children (OR: 1.74; 95% CI: 1.66, 1.82). A similar pattern was also observed in different sex and area groups, and in children 9-14 years old. Conclusions An intensified association between WC and hypertension was observed in abdominally overweight Chinese children. The gain in WC was associated with greater increase in hypertensive risk in abdominally overweight children than that of children with normal WC. These findings could improve intervention strategies for hypertension risk reduction in children