A prospective study of the effect of hypertension and baseline blood pressure on cognitive decline and dementia in postmenopausal women: the Women's Health Initiative Memory Study.

OBJECTIVES: To examine the relationship between baseline hypertension, blood pressure, and the development of cognitive decline in participants in the Women's Health Initiative Memory Study (WHIMS).

DESIGN: Prospective analyses.

SETTING: Thirty-nine centers.

PARTICIPANTS: Seven thousand one hundred forty-nine women aged 65 and older.

MEASUREMENTS: The Modified Mini-Mental State Examination (3MS) was used to assess global cognitive functioning. Participants who scored below pre-established cutpoints were scheduled for more-extensive neurocognitive assessments. Results from these assessments were centrally adjudicated.

RESULTS: The mean age of this group of 7,149 participants at baseline was 71.0 +/- 3.8, and the mean 3MS score was 95.2 +/- 4.3. During a mean follow-up period of 4.5 years, women without hypertension tended to have slightly higher 3MS scores than women with hypertension (P=.001), but the difference was not seen after adjustment for covariates (P=.17). Women with hypertension also appeared to be at greater risk for probable dementia or mild cognitive impairment (MCI) (hazard ratio=1.35, 95% confidence interval=1.07-1.70, P=.01), although when potential cofounders were accounted for, this association was no longer significant (P=.06).

CONCLUSION: Hypertension and high blood pressure at baseline were not independently associated with MCI or probable dementia over time in older, cognitively intact, postmenopausal women enrolled in WHIMS after other potential confounders were taken into account. These analyses should not be viewed as discouraging appropriate medical treatment for hypertension.