Does body mass index or waist-hip ratio correlate with arterial stiffness based on brachial-ankle pulse wave velocity in Chinese rural adults with hypertension?

BACKGROUND: The relationship between obesity indices and arterial stiffness (AS) has not been fully discovered nor has it been studied in depth in large hypertensive patient populations. The aim of this study was to explore the association between body mass index (BMI) and waist-hip ratio (WHR) levels and AS based on brachial-ankle pulse wave velocity (baPWV) in Chinese rural adults with hypertension. METHODS: This cross-sectional study analyzed 5049 Chinese rural adults with essential hypertension. BMI was calculated as the body weight in kilograms divided by the square of the height in meters (kg/m(2)). Central obesity was defined as WHR ≥ 0.9 for males and ≥ 0.85 for females. Measurement of arterial stiffness was carried out via brachial-ankle pulse wave velocity (baPWV). RESULTS: The prevalence of overweight, general obesity, central obesity and increased AS were 26.88%, 3.39%, 63.85% and 44.01%, respectively. Multivariate logistic regression analysis indicated that BMI levels were negatively associated with the prevalence of increased AS (adjusted-OR per SD increase: 0.74, 95% CI 0.67–0.81, P < 0.001). When BMI was instead treated as a categorical variable divided into tertiles, the same relationship was observed (P for trend < 0.001). Inversely, WHR levels were positively associated with the prevalence of increased AS (adjusted-OR per SD increase: 1.25, 95% CI 1.14–1.36, P < 0.001). Compared to subjects without central obesity, those with central obesity had a higher prevalence of increased AS (adjusted-OR: 1.52, 95% CI 1.28–1.81, P < 0.001). Linear regression models indicated similar results in the correlation between BMI or WHR levels and baPWV levels (adjusted-β per SD increase: − 0.57, 95% CI − 0.68 to − 0.46, P < 0.001; adjusted-β per SD increase: 4.46, 95% CI 3.04–5.88, P < 0.001). There were no interactions in terms of age and blood pressure on the relationship between BMI or WHR levels and the prevalence of increased AS or baPWV levels. CONCLUSION: There was an inverse relationship between BMI levels and increased AS or baPWV levels, whereas WHR levels and central obesity were positively associated with increased AS or baPWV levels in Chinese rural adults with hypertension. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12872-021-02390-y.