Effect of intensive blood pressure control on subtypes of mild cognitive impairment and risk of progression from SPRINT study

BACKGROUND: To examine the effect of intensive blood pressure control on the occurrence of subtypes of mild cognitive impairment (MCI) and determine the risk of progression to dementia or death. METHODS: Secondary analysis of a randomized trial of community-dwelling adults (≥50 years) with hypertension. Participants were randomized to a systolic blood pressure (SBP) goal of <120 mm Hg (intensive treatment; n = 4678) or <140 mm Hg (Standard treatment; n = 4683). Outcomes included adjudicated MCI, MCI subtype (amnestic, non-amnestic, multi-domain, single domain), and probable dementia. Multistate survival models were used to examine transitions in cognitive status accounting for the competing risk of death. RESULTS: Among 9361 randomized participants (mean age, 67. 9 years; 3332 women 35. 6%), 640 participants met the protocol definition for MCI, with intensive treatment reducing the risk of MCI overall (hazard ratio HR, 0. 81 95% confidence interval CI, 0. 69-0. 94), as previously reported. This effect was largely reflected in amnestic subtypes (HR, 0. 78 95% CI, 0. 66-0. 92) and multi-domain subtypes (HR, 0. 78 95% CI, 0. 65-0. 93). An adjudication of MCI, as compared with normal cognitive function, substantially increased the probability of progressing to probable dementia (5. 9% 95% CI: 4. 5%-7. 7% vs. 0. 6% 95% CI: 0. 3%-0. 9%) and to death (10. 0% 95% CI: 8. 3%-11. 9% vs. 2. 3% 95% CI: 2. 0%-2. 7%) within 2 years. CONCLUSIONS: Intensive treatment reduced the risk for amnestic and multi-domain subtypes of MCI. An adjudication of MCI was associated with increased risk of progression to dementia and death, highlighting the relevance of MCI as a primary outcome in clinical and research settings.