Background: The relationship between systolic blood pressure (SBP) and longevity is not fully understood. We aimed to determine which SBP levels in women ≥65 years of age with or without blood pressure medication were associated with the highest probability of surviving to 90 years of age.

Methods: The study population consisted of 16 570 participants enrolled in the Women's Health Initiative who were eligible to survive to 90 years of age by February 28, 2020, without a history of cardiovascular disease, diabetes, or cancer. Blood pressure was measured at baseline (1993 through 1998) and then annually through 2005. The outcome was defined as survival to 90 years of age with follow-up. Absolute probabilities of surviving to 90 years of age were estimated for all combinations of SBP and age using generalized additive logistic regression modeling. The SBP that maximized survival was estimated for each age, and a 95% CI was generated.

Results: During a median follow-up of 19.8 years, 9723 of 16 570 women (59%) survived to 90 years of age. Women with an SBP between 110 and 130 mm Hg at attained ages of 65, 70, 75, and 80 years had a 38% (95% CI, 34%-48%), 54% (52%-56%), 66% (64%-67%), or 75% (73%-78%) absolute probability to survive to 90 years of age, respectively. The probability of surviving to 90 years of age was lower for greater SBP levels. Women at the attained age of 80 years with 0%, 20%, 40%, 60%, 80%, or 100% time in therapeutic range (defined as an SBP between 110 and 130 mm Hg) had a 66% (64%-69%), 68% (67%-70%), 71% (69%-72%), 73% (71%-74%), 75% (72%-77%), or 77% (74%-79%) absolute survival probability to 90 years of age.

Conclusions: For women >65 years of age with low cardiovascular disease and other chronic disease risk, an SBP level <130 mm Hg was found to be associated with longevity. These findings reinforce current guidelines targeting an SBP target <130 mm Hg in older women.