Association between baseline office blood pressure level and the incidence and development of long-term frailty in the community-dwelling very elderly with hypertension

Frailty is the most important risk factor causing disability in the elderly. Hypertension is one of the most common chronic diseases in the elderly and is closely related to frailty, but there is still controversy about the association between blood pressure and frailty. To explore the association between baseline blood pressure level and the incident and development of long-term frailty in the community-dwelling very elderly (i.e., over 80 years old [1]) with hypertension, in order to provide a basis for scientific blood pressure management of very elderly hypertension. In this study, very elderly hypertensive patients who received comprehensive geriatric assessment from January to June 2019 and with complete data were included, and follow-up was conducted from January 1 to February 14, 2023. A total of 330 very elderly individuals with hypertension were enrolled in this study. FRAIL scale was used to evaluate frailty. Binomial logistic regression analysis was used to calculate the OR and 95%CI between baseline systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) levels and long-term incident and development of frailty. The dose-response relationship between baseline office SBP, DBP or PP levels and incident frailty and its development was analyzed by Generalized Additive Model (GAM) using smooth curve fitting and threshold effect analysis. Smooth curve fitting and threshold effect analysis showed that the relationship between baseline office SBP level and incident frailty was U-shaped, with the nadir of the U-shaped curve at 135 mmHg after adjustment. Baseline office SBP, PP level and development frailty was U-shaped and the nadir was 140 mmHg and 77 mmHg. In the community-dwelling very elderly with hypertension, baseline office SBP level had a relationship with long-term incident frailty and its development and PP level had a relationship with long-term development of frailty. Conclusion In community-dwelling very elderly (>= 80years) hypertensive patients, the baseline SBP showed a U-shaped curve relationship with the incident and development of long-term frailty, with the inflection points of the U-shaped curve being 135 mmHg and 140 mmHg, respectively, and the baseline PP level showed a U-shaped curve relationship with the development of long-term frailty, with the inflection point of 77 mmHg.