Visit-to-visit variability in systolic blood pressure is a novel risk factor for the progression of coronary artery calcification

Recent studies have suggested that variability in the systolic blood pressure (SBP) is a risk factor for cardiovascular disease (CVD). The aim of this study was to investigate the relationship between variability in the SBP and the progression of coronary artery calcification (CAC), which is a useful marker for CVD. We measured SBP in 164 consecutive patients at every visit over the course of a year and calculated the coefficient of variation and s.d. of the SBP. We performed a follow-up study using multislice computed tomography to assess the progression of the CAC score, the mean interval of which was 3.93±1.36 years. We then evaluated the relationship between variability in the SBP and progression of the CAC score. The coefficient of variation for the SBP correlated positively with the progression of the CAC score (r=0.4382, P<0.0001). Multiple regression analysis demonstrated that the coefficient of variation of the SBP (β=0.3826, P<0.0001) was independently associated with the progression of the CAC score. The visit-to-visit variability in SBP could be a novel risk factor for the progression of CAC.