Within-visit and short- and long-term between-visit blood pressure variability as predictors of cardiovascular events and mortality in elderly Chinese

We investigated the prognostic value of within-visit and short- and long-term between-visit blood pressure variability (BPV) for all-cause and cardiovascular mortality, fatal and nonfatal cardiovascular events and incident atrial fibrillation in an elderly Chinese population. Participants were elderly (≥65 years) inhabitants, enrolled in a trial for atrial fibrillation screening. Blood pressure was measured three times consecutively at baseline and in a subset also at least two weekly visits during the first month of follow-up or at least two quarterly visits during the first year of follow-up. BPV indices included standard deviation, coefficient of variation, and other statistical measures. We computed hazard ratios (HR) for the risks of clinical outcomes associated with a 1-SD increase in these BPV indices, while accounting for confounding factors. Among 6711 participants, diastolic within-visit BPV indices were significantly (P ≤ 0.02) and positively associated with the risks of all-cause and cardiovascular mortality, and fatal and nonfatal cardiovascular events, but systolic BPV indices were negatively associated with the risk of incident atrial fibrillation (HRs 1.03-1.09 and 0.87-0.92, respectively). Among 362 participants, none of the short-term between-visit BPV indices were associated with the clinical outcomes (P ≥ 0.09). For the long-term between-visit BPV among 1582 participants, significant associations were observed for systolic BPV indices in relation to cardiovascular mortality (P ≥ 0.03), and diastolic BPV indices in relation to incident atrial fibrillation (P ≤ 0.03), with the HRs ranging from 1.05-1.43, and from 1.07-1.20, respectively. In conclusion, some of the BPV indices were weakly associated with the risk of mortality, cardiovascular events and incident atrial fibrillation.