Cognitive performance in hypertensive and normotensive older subjects.
Harrington F., Saxby BK., McKeith IG., Wesnes K., Ford GA.
Longitudinal studies suggest that hypertension in midlife is associated with cognitive impairment in later life. Cross-sectional studies are difficult to interpret because blood pressure can change with onset of dementia and the inclusion of subjects on treatment and with hypertensive end-organ damage can make analysis difficult. We examined cognitive performance in hypertensive and normotensive subjects without dementia or stroke >/=70 years of age. Cognitive performance was determined with the use of a computerized assessment battery in 107 untreated hypertensives (55 women, age 76+/-4 years, blood pressure, 164+/-9/89+/-7; range, 138 to 179/68 to 99 mm Hg) and 116 normotensives (51 female, age 76+/-4 years, 131+/-10/74+/-7; 108 to 149/60 to 89 mm Hg). Older subjects with hypertension were significantly slower in all tests (reaction time, milliseconds; simple, 346+/-100 versus 318+/-56, P<0.05; memory scanning, 867+/-243 versus 789+/-159, P<0.01; immediate word recognition, 947+/-261 versus 886+/-192, P<0.05; and delayed word recognition, 937+/-230 versus 856+/-184, P<0.05; picture recognition, 952+/-184 versus 894+/-137, P<0.01; spatial memory, 1390+/-439 versus 1258+/-394, P<0.01; excepting choice reaction time, 510+/-75 versus 498+/-72, P=0.08). Accuracy was also impaired in tests of number vigilance, 99.2+/-2.5% versus 99.9+/-0.9, P<0.01; delayed word recognition, 83.5+/-16 versus 87.9+/-9.8, P<0.01; and spatial memory 64+/-32 versus 79+/-20, P<0.001. Hypertension in older subjects is associated with impaired cognition in a broad range of areas in the absence of clinically evident target organ damage.