Brachial–ankle pulse wave velocity compared with mean arterial pressure and pulse pressure in risk stratification in a Chinese population
Brachial–ankle pulse wave velocity (baPWV) can be easily measured in an observer-independent way, but lacks robust population-based validation in terms of fatal combined with nonfatal outcomes.Method:
To address this issue, we studied 4251 Chinese randomly recruited Gaoyou County (54.1% women; mean age, 52.1).Results:
In the whole study population, mean values were 102.4 mmHg for mean arterial pressure (MAP), 51.1 mmHg for pulse pressure, and 14.8 m/s for baPWV. Over 4.4 years (median), 74 participants experienced a fatal or nonfatal cardiovascular event and 44 a stroke. In multivariable-adjusted Cox regression, standardized hazard ratios expressing the risk of a composite cardiovascular endpoint were 1.77 (95% confidence interval, 1.43–2.20), 1.37 (1.14–1.64) and 1.50 (1.26–1.78) for MAP, PP and baPWV, respectively; the corresponding hazard ratios for stroke were 1.82 (1.39–2.38), 1.39 (1.12–1.74) and 1.53 (1.25–1.89). baPWV did not add to the prediction of cardiovascular events or stroke by MAP (hazard ratios for baPWV, 1.25 and 1.27, respectively; P ≥ 0.053) but refined models including PP (hazard ratios, 1.42 and 1.45; P ≤ 0.0033). The optimized baPWV threshold, obtained by maximizing Youden's index (16.7 m/s), increased the integrated discrimination improvement over and beyond MAP (+1.27%; P = 0.021) and PP (+1.37%; P = 0.038) for the cardiovascular outcome, but not stroke, and increased the net reclassification improvement for both endpoints (≥42.2%; P ≤ 0.004).Conclusion:
With fatal and nonfatal cardiovascular and cerebrovascular endpoints as outcome, baPWV marginally increases risk stratification over and beyond MAP, but is a better predictor than PP. A threshold of 16.7 m/s might be used in Chinese populations.