Determinants of Waist-to-Height Ratio and Its Relation to Hypertension among School Children in India: A Multicenter Study.

Objective: To study the factors associated with waist-to-height ratio (WHtR) among school children aged 5-15 y and its association with hypertension.

Methods: In this cross-sectional study, data on background characteristics, socioeconomic status (SES), anthropometric parameters, and blood pressure were obtained from school children from three states of India. WHtR ≥ 0.5 was defined as obesity and hypertensives were defined based on Fourth Report criteria. Descriptive statistics were applied and multiple linear regression was done to identify factors associated with WHtR. A receiver operating characteristics (ROC) analysis was used to evaluate the predictive ability of WHtR to predict hypertension RESULTS: The mean WHtR among the 12,068 students was 0.40 (± 0.05) and it showed a U-shaped distribution with age with trough at 10 y of age for both genders. Mean WHtR was higher among residents of Manipur, among boys and hypertensives. WHtR was positively associated with weight > 30 kg, male gender, schools with high SES, Manipur and Goa region, and negatively associated with age > 10 y. The area under the ROC curve of WHtR for diagnosis of hypertension was low 0.544 (95% CI 0.532, 0.556).

Conclusion: There is a nonlinear relation between age, gender, and WHtR, which varies by geographical region and HT. This would need to be kept in mind while using it to identify obesity in children, though its discriminant value for hypertension is low.