Relationships of Office, Ambulatory, and Self-measured Blood Pressure With Cardiac, Renal, and Atherosclerotic Biomarkers

BACKGROUND: Previous studies with several limitations have comparatively analyzed the relationship between ambulatory blood pressure (BP) and self-measured BP and biomarkers of organ damage. This study extends this line of research by examining the relationship between ambulatory and self-measured BP and cardiac, renal, and atherosclerotic biomarkers in outpatients at cardiovascular risk. METHODS: In 1,440 practice outpatients who underwent office, ambulatory, and self-measured BP monitoring, we assessed the relationships of each BP with organ damage biomarkers including b-type natriuretic peptide (BNP), echocardiographic left ventricular mass index (LVMI), urine albumin-creatinine ratio (UACR), and brachial-ankle pulse wave velocity (baPWV). RESULTS: In the comparison of correlation, self-measured systolic BP (SBP) was more strongly correlated to log-transformed (Ln) BNP (n = 1,435; r = 0.123 vs. r = -0.093, P < 0.001), LVMI (n = 1,278; r = 0.223 vs. r = 0.094, P < 0.001), Ln-UACR (n = 1,435; r = 0.244 vs. r = 0.154, P = 0.010), and baPWV (n = 1,360; r = 0.327 vs. r = 0.115, P < 0.001) than daytime ambulatory SBP. In the linear regression models including office, ambulatory, and self-measured SBP, only self-measured SBP was significantly related to Ln-BNP (P = 0.016) and LVMI (P < 0.001). In the logistic regression models for the top quartile of LVMI, adding self-measured SBP improved the model predictability (P = 0.027), but adding daytime ambulatory SBP did not. However, adding daytime ambulatory SBP improved the model predictability in the logistic model for the top quartile of baPWV including office and self-measured SBP (P = 0.030). CONCLUSIONS: Our study findings suggested that self-measured BP was associated with cardiac biomarkers independent of ambulatory BP.