Abstract MP06: Women but Not Men With a Systolic Blood Pressure Greater the 110mmhg Was Associated With Higher Risk of All-Cause Dementia

Introduction: Whether the association of blood pressure levels and risk of dementia differed by sex remains unclear. Hypothesis: We hypothesized that there might be a sex difference in the association between blood pressure levels and dementia. Methods: We used cohort data from UK Biobank, a large population-based prospective cohort study that recruited 502 649 individuals ages 40-69, between 2006 and 2010. Cox proportional hazards models were used to estimate sex-specific hazard ratios (HRs) and 95% confidence intervals (CI) for the association between blood pressure levels and incident dementia (including all-cause dementia, Alzheimer's Disease (AD), vascular dementia). We conducted subgroup analyses to divide people into two categories of baseline age < 60 years and ≥60 years. Restricted cubic spline models were used to estimate the association between blood pressure levels and all-cause dementia. Results: Overall, 425504 (53.9% women) people with no prevalent dementia were included. After 11.4 (median) years follow-up, 5114 participants (46.2% women) developed dementia. The crude incidence rates were 10.3 for women and 14.0 for men, per 10,000 person-years. The relationship between diastolic blood pressure (DBP) and dementia was U-shaped in both men and women. Women with higher SBP levels were associated with higher risk of all-cause dementia, with an SBP threshold of 110mmhg. Also, women with SBP levels greater than a threshold of 120mmhg and 150mmhg was linked to higher risk of AD and VD, respectively. No relationship between SBP and dementia was observed in men. After the analyses were stratified by age when the SBP was measured (<60 years or ≥60 years), we found that in women younger than 60 years, a nonlinear relationship was observed, i.e., high SBP level greater than 120mmhg was linked to higher risk of all-cause dementia. Conclusions: Women with a threshold of SBP level greater the 110mmhg was associated with higher risk of all-cause dementia, while no such relationship was observed in men.