Brachial-ankle versus carotid-femoral pulse wave velocity: a systematic review and meta-analysis.

Carotid-femoral pulse wave velocity (cfPWV) is the reference method for measuring large artery stiffness. Automated brachial-ankle pulse wave velocity (baPWV) is an alternative method for assessing medium-to-large artery stiffness. A systematic review/meta-analysis was performed to investigate the relationship of cfPWV and baPWV measurements regarding their difference and association, and their relationship with indices of subclinical target organ damage (TOD) and cardiovascular outcomes. Among 1000 records initially retrieved, 51 were included ( n  = 36 126). Meta-analysis of 46 studies [ n  = 32 426, weighted mean age 61 years, men 49%, BMI 25.1 kg/m 2 , SBP/DBP 129/75 mmHg, hypertension 58%, diabetes 23%, smokers 17%, baPWV 15.82 m/s, cfPWV 9.47 m/s] indicated a pooled baPWV-cfPWV mean difference 5.03 m/s [95% confidence intervals (4.34-5.72)]. Meta-analysis of 23 studies ( n  = 10 880, age 58 years, men 58%, BMI 26.2 kg/m 2 , BP 126/74 mmHg, hypertension 41%, diabetes 16%, smokers 13%) indicated a pooled baPWV vs. cfPWV Pearson correlation coefficient 0.68 (0.61, 0.74). Similar correlations of baPWV/cfPWV with left ventricular mass index, carotid intima-media thickness and urine albumin-to-creatinine ratio were found. Limited data indicated a slightly higher predictive value of cfPWV for cardiovascular outcomes. Sensitivity and multivariable meta-regression analyses indicated significant associations of pooled baPWV-cfPWV mean difference with the distance used for cfPWV calculation and baPWV/cfPWV devices. baPWV and cfPWV are strongly correlated to each other and similarly to subclinical TOD, but baPWV gives higher values. There is considerable heterogeneity among the available studies and standardized design and methodology is needed in future research.