Waist-to-height ratio a useful screening tool for early hypertension detection in teens

Waist-to-height ratio (WHtR) provides an easy-to-use tool for screening hypertension risk in adolescents, with optimal cutoff values of 0.45 in boys and 0.46 in girls, according to a study from Malaysia.

Researchers looked at 513 adolescents (58.9 percent female) aged 12–16 years from two schools in Selangor state, Malaysia. They compared the predictive power of different anthropometric indices (body mass index [BMI], waist circumference [WC], WHtR and a body shape index [ABSI]) for blood pressure (BP) elevation, in addition to determining the optimal cut-off values for differentiating high BP.

According to the classifications of BMI-for-age, about one third of the population was overweight or obese (32.6 percent). The prevalence rate of abdominal obesity was 14.0 percent based on WC and 18.5 percent based on WHtR classifications. A total of 19.1 percent adolescents were found to have prehypertension, whereas 11.9 percent had hypertension stage 1 or 2.

The BMI-for-age, WC and WHtR indices showed good predictive power in identifying BP elevation, with areas under the curve (AUCs) ranging from 0.81 to 0.86. ABSI, on the other hand, had an acceptable predictive power with an AUC of <0.8.

Based on the Youden index, the corresponding optimal cut-off values in boys and girls for predicting high BP were 1.87 and 1.18 for BMI-for-age, the 78th and the 73rd percentile for WC, 0.52 and 0.45 for WHtR, and 0.15 and 0.14 for ABSI.

WHtR had the highest sensitivity (>90.0 percent) for identifying hypertensive adolescents in the entire population and in girls, whereas BMI-for-age had the highest specificity (>80.0 percent) for identifying those with normal BP.

The present data point to the potential value of WHtR for fast and mass hypertension screening in clinical and community settings, especially because the index is independent of age and sex, the researchers said. WHtR can also be used to develop successful prevention and screening interventions for abdominal obesity and hypertension among adolescents.