Elderly patients with mild to moderate hypertension and lowered cognitive function show greater cognitive decline, compared with equivalent hypertensive individuals with high cognitive function, a posthoc analysis shows.
The first Study on Cognition and Prognosis in the Elderly (SCOPE) analysis showed inconclusive results in demonstrating that antihypertensive treatment, primarily with candesartan, may preserve cognitive function and reduce the incidence of dementia, according to Ingmar Skoog, M.D., of Sahlgrenska University Hospital, Göteborg, Sweden, and colleagues in the international SCOPE study group.
The post hoc analysis was performed to compare cognitive and cardiovascular outcomes between 2,070 patients with slightly lower baseline cognitive function (LCF) as defined by Mini-Mental State Examination (MMSE) scores of 24–28, and 2,867 patients with higher cognitive function (HCF), defined by MMSE scores of 29–30 (Am. J. Hypertens. 2005;18:1052–9).
Additionally, the analysis separately compared cognitive and cardiovascular outcomes in the candesartan with the control groups for LCF and HCF patients.
Significant cognitive decline was nearly twice as common in patients with LCF (6.6%), compared with patients with HCF (3.6%). Cognitive decline did not differ significantly between candesartan and control groups. (For ethical reasons in the SCOPE trial, control patients also were given off-label active hypertensive therapy when deemed necessary, primarily with hydrochlorothiazide, significantly lowering blood pressure in both treatment groups).
Dementia onset during the study was found to be over four times as common in patients with LCF (4.4%) as in patients with HCF (1.0%). Here, too, no difference was seen between the candesartan and control groups, Dr. Skoog and colleagues reported.
Contrary to perceived fears by many physicians that lowering blood pressure in the elderly would cause cognitive decline because of reduction in cerebral blood flow, cognitive function changed very little, even in patients with LCF, the authors reported. In addition, dementia incidence in the study was found to be in the lower range of expectation for this age group. Thus, there appeared to be no negative effect of blood pressure control, according to the report.
Such evidence, coupled with the observation that mild to moderate hypertension and slightly impaired cognitive function in the elderly at baseline were associated with increased risk of significant cognitive decline and dementia, indicate that effective antihypertensive therapy may reduce cognitive decline in these patients, Dr. Skoog and colleagues concluded.