BMI, Waist to Height Ratio and Waist Circumference as a screening tool for Hypertension in Hospital out Patients: A Cross-Sectional, Non-inferiority study

Objective: The study aimed to determine the burden of obesity, using three commonly employed metrics in the hospital outpatient setting of a developing country as predictors of hypertension through a non-inferiority study. Design: A cross-sectional study design was adopted. Setting: This study was conducted in Health Promotion and Risk Factor Screening Service in a tertiary Eye and ENT hospital in a semi-urban area of Nepal. Participants 2,256 randomly selected 40-69 years outpatients. Outcome measures C orrelation analysis, the area under the Receiver Operating Characteristic curve, Odds ratios (OR) were calculated between three obesity metrices and hypertension. Results: The prevalence of obesity and overweight by BMI was 16.09% and 42.20%, respectively; by WHtR was 32.76%, which is two times higher than obesity measured by BMI. High WC was observed among 66.76% of participants. Female participants had a greater prevalence of high WC (77.46%) than males (53.73%) (p<0.001). Prevalence of hypertension and pre-hypertension was 40.67% and 36.77%, respectively. The areas under the curve were significantly higher than 0.5 for BMI (0.593), WHtR (0.602), and WC (0.610). Conclusion: WC correlated well with obesity and hypertension. It also had a higher predicting ability than WHtR and BMI to predict hypertension. WC thus proved to be non-inferior to two other commonly used metrics. It proved superior in detecting obesity in female. This inexpensive and simple non-tension tape measurement may play an important role in the future diagnosis of obesity and the prediction of HTN in resource-constrained settings of developing countries.