a positive trendP = 0.059
Regression analysis In univariate analysis, the RRI was positively correlated with age ( r = 0.36, P = 0.013), SBP ( r = 0.32, P = 0.011), PP ( r = 0.31, P = 0.017) and media-to-lumen ratio ( r = 0.39, P = 0.003); RRI and the inhibitory response of L-NAME to ACh vasodilation showed a positive trend ( r = 0.25, P = 0.059).