Hypertension and cholesterol lowering interventions do not reduce cognitive decline
Blood pressure lowering medications and statins do not prevent cognitive and functional decline in elderly patients, according to results of the HOPE-3 trial* presented at the Scientific Sessions of the American Heart Association (AHA 2016) held recently in New Orleans, Louisiana, US.
To study the impact of lipid and blood pressure lowering interventions on changes in cognitive function, researchers of this multicentre trial (228 centres in 21 countries) randomized 12,705 participants to receive the blood pressure lowering drugs candesartan/hydrochlorothiazide or placebo and the cholesterol lowering drug rosuvastatin or placebo. [AHA 2016; LBCT 01]
Of the 3,086 individuals aged ≥70 years (mean age 74 years, 59 percent women) with an intermediate risk of cardiovascular disease, 2,361 completed a baseline questionnaire and were followed up for an average duration of 5.7 years. At study conclusion, 2,142 patients were alive, 76 percent (n=1,626) of whom completed both baseline and study end questionnaires.
The primary outcome was the decline in processing speed as measured by the Digit Symbol Substitution Test (DSST), while the decline in executive function and increase in psychomotor speed (secondary outcomes) were measured using a modified version of the Montreal Cognitive Assessment (mMoCA) and Trail Making Test Part B (TMT-B), respectively.
Participants in both groups experienced cognitive decline though there were no between-group differences. The changes in mean DSST score were 0.1 (p=0.86) for those on blood pressure lowering medication vs placebo, -0.5 (p=0.38) for those on rosuvastatin vs placebo, and -0.4 (p=0.63) for those on both blood pressure lowering medications and rosuvastatin vs double placebo.
The study also found that rosuvastatin did not appear to have an adverse effect on cognitive function. Subgroup analysis found that a longer duration of blood pressure lowering intervention was associated with less cognitive decline, a finding that requires further study, according to the researchers.
“There was no difference in mental processing speed, in executive function, in psychomotor speed, or other cognitive or functional areas tested between the groups,” said Dr Jackie Bosch from the Population Health Research Institute, McMaster University and Hamilton Health Sciences in Hamilton, Ontario, Canada, who presented the results on behalf of the HOPE-3 researchers.
“We know that blood pressure effects begin in middle-age. We need to think about treating earlier and treating longer to affect cognitive function, especially for individuals at higher cardiovascular risk,” she said.