A prospective study of variability in systolic blood pressure and mortality in a rural Bangladeshi population cohort

Objective: Limited studies suggest that blood pressure variability over time is a risk factor of long-term cardiovascular outcomes. However, most of these were in populations with pre-existing cardiovascular diseases (CVD) and studies in general population are lacking. Methods: The study included 11,153 participants in a population-based, prospective cohort study in Araihazar, Bangladesh. Resting blood pressure was measured at baseline and every two years thereafter. Participants were followed up for an average of 6.5. years (2002-2009). Results: Male gender, older age, baseline systolic blood pressure (SBP), and absence of betel leaf use were independently positively associated with greater SBP variability over time. There was a significant association between SBP variability and the risk of death from overall CVD, especially from major CVD events. The positive association with the risk of death from any cause and stroke in age- and sex-adjusted models was attenuated in fully-adjusted models. In addition, the hazard ratio (HR) of stroke mortality was greater for individuals with both high baseline and high SBP variability. Similar patterns of HRs were observed for all-cause and CVD mortalities. Conclusion: In this rural Bangladeshi population, variability in SBP contributes to the risk of death from CVD and may further potentiate the increased mortality risk associated with high SBP.