THE EFFECTS OF MILD DIASTOLIC HYPERTENSION ON THE RESULTS OF TESTS OF COGNITIVE FUNCTION IN ADULTS 22 TO 59 YEARS OF AGE

Objective: To test the hypothesis that mild diastolic hypertension (90 to 104 mm Hg) may induce asymptomatic impairment of cognitive function. Design: Cross-sectional. Setting: Community participants recruited to a university-based ambulatory care center. Participants: Three hundred twelve men and women with untreated essential hypertension and 47 normotensive subjects, 22 to 59 years of age. Measurements and main results: Cognitive function tests measured reaction time to and accuracy in interpreting predetermined visual stimuli, the ability to acquire, reproduce, and change a set of arbitrary stimulus-response associations, and memory and learning of verbal information. These tests were selected to detect subtle differences in performances as opposed to differentiating neurologically normal persons from brain-damaged persons. After controlling for age, gender, and education, results showed that there was no significant difference between the normotensive and hypertensive subjects in two measures of reaction time to and four measures of accuracy in interpreting predetermined visual stimuli, in the measure of arbitrary stimulus-response associations, or in seven memory and learning variables. Although confidence intervals for the differences between means were wide, clinically significant differences were not likely to be present. Younger age was associated with faster reaction times, fewer errors, and better performance on memory and learning tasks, independent of diastolic blood pressure. Conclusions: The few detectable effects of untreated mild hypertension on cognitive function reported in the literature may be due to chance and are of questionable clinical significance.