THE EFFECTS OF ANTIHYPERTENSIVE TREATMENT ON COGNITIVE FUNCTION - RESULTS FROM THE HOPE STUDY

OBJECTIVES: Hypertension is associated with impaired cognition, but it is unclear whether this impairment is reversible. We sought to evalua te the effect of blood pressure reduction on cognition. DESIGN: A rand omized, double-blind trial. SETTING: A single center, with assessments in subjects' domiciles. PARTICIPANTS: Community-screened subjects mor e than 69 years of age who had median diastolic pressures >99 mm Hg an d systolic pressures >159 mm Hg or diastolic >85 mm Hg and systolic >1 79 mm Hg with Mini-Mental State Examination scores of 20 to 28. Subjec ts had not previously received antihypertensive treatment. INTERVENTIO N: Captopril 12.5 mg twice daily or bendrofluazide 2.5 mg daily for 24 weeks, preceded by a 2-week placebo phase. MEASUREMENTS: Cognition wa s evaluated by a psychometric test battery comprising Immediate and De layed Logical Memory, Paired Associates recall, Raven's Progressive Ma trices, Halstead Reitan Trail Making A, and the Anomalous Sentences Re petition Test. RESULTS: Eighty-one subjects (28 male, 53 female) were treated (41 captopril, 40 bendrofluazide). At entry, mean age was 76.1 years (range 70-84), mean blood pressure was 191 (160-230) mm Hg syst olic, 101 (88-110) mm Hg diastolic, and mean MMSE score 26.1. A total of 69 subjects completed the trial. The 25th, 50th, and 75th percentil es of the difference between pretreatment and Week 24 blood pressures were 15 mm Hg, 35 mm Hg, and 50 mm Hg (systolic) and 5 mm Hg, 10 mm Hg , and 19 mm Hg (diastolic). There were no significant differences in a ny psychometric test between captopril and bendrofluazide. The 19 subj ects in the quartile that lowered their diastolic blood pressure most (greater than or equal to 19 mm Hg) had improved scores on Anomalous S entences (P = .012) and Paired Associates (P = .044) compared to the 1 9 subjects in the least blood pressure responsive quartile (fall less than or equal to 5 mm Hg)s. CONCLUSION: The treatment of hypertension is not hazardous to cognitive function in older people with pre-existi ng cognitive impairment. Long-term adequate blood pressure control may reverse cognitive impairment associated with pre-existing hypertensio n.