LAUSR

Introduction: Systolic blood pressure (SBP) time in target range (TTR) was proven to be a new parameter to predict cardiovascular outcomes. However, the prognostic value for cognitive function is unclear. Hypothesis: Higher TTR was associated with lower incidence of cognitive outcomes. Methods: We performed a post hoc analysis from the Systolic Blood Pressure Intervention Trial (SPRINT), a randomized controlled trial comparing intensive (<120 mm Hg) and standard (<140 mm Hg) SBP interventions in 9361 individuals with hypertension. SBP target range was defined as 110 to 130 mm Hg for the intensive group and 120 to 140 mm Hg for the standard group. Participants who had less than 3 SBP measurements during this period or no cognitive assessment in the follow-up were excluded. TTR was calculated by linear interpolation using SBP from baseline to the first 3 months of follow-up. Cognitive outcomes were probable dementia, mild cognitive impairment (MCI), and a composite of probable dementia or MCI. Cox regression models were used to evaluate the relationship between TTR and cognitive outcomes. Results: A total of 8415 patients were included in this study. In univariate Cox regression analysis, higher time in target range was associated with lower risk of probable dementia. After adjustment for age, sex and race, a 1-SD increase in TTR was independently associated with a 16% lower risk of probable dementia (hazard ratio [HR] =0.84, 95% CI 0.75-0.93, P =0.002) (Figure). When we further added demographics, medical history and mean SBP to the multivariate Cox regression model, TTR remained significantly associated with a decreased risk of probable dementia (HR =0.84, 95% CI 0.74-0.96, P =0.012). No significant relationship was found between TTR and MCI or a composite of probable dementia or MCI. Conclusions: In this post hoc analysis of the SPRINT trial, SBP time in target range was an independent predictor of probable dementia beyond mean SBP levels.