Amlodipine reduces long-term stroke risk but not dementia


Patients who took amlodipine as part of an antihypertensive regimen experienced significantly fewer strokes over two decades, new long-term results from the ASCOT study show. This group showed an 18% decrease in stroke incidence compared with others taking an atenolol-based regimen.

However, neither therapy was associated with an overall decrease in dementia incidence in the multicenter, randomized study.

Investigators also compared atorvastatin to placebo in a separate analysis. The statin did not significantly reduce either stroke or dementia rates.

The investigators focused on the ASCOT subpopulation of 8580 UK participants from a total of 19,342 patients in the overall trial. The researchers enrolled people with hypertension, three or more vascular risk factors and no coronary heart disease from 1998 to 2002. They randomly assigned participants to an amlodipine- or atenolol-based regimen in a study that lasted 5.5 years.

That group of the trial (ASCOT-Blood Pressure Lowering Arm) was stopped early in 2004 when a reduction in all-cause mortality was seen with the amlodipine-based regimen, although the primary endpoint, a 10% reduction in nonfatal myocardial infarction and fatal coronary heart disease, was not statistically different between the groups, something the researchers attributed to the early stop.

At the same time, ASCOT investigators also compared atorvastatin vs placebo (ASCOT-Lipid Lowering Arm) in a factorial 2 x 2 design among participants whose total cholesterol was 6.5 mmol/L or less. That group of the study was stopped at 3.3 years because of overwhelming benefit on myocardial infarction.

The researchers tracked all stroke and all dementia diagnoses using coding in national health records, and noted deaths, general hospitalizations, mental health consultations, prescriptions, and more.

A majority, 81%, of the study participants were men and 90% were of European ancestry. At baseline, mean systolic BP was 162 mm Hg and mean diastolic BP was 92 mm Hg. Total cholesterol was 5.9 mmol/L.