Controlling blood pressure even when older can prevent dementia in African Americans

African Americans are especially at risk of both hypertension and dementia. The new study provides substantial evidence of significant reduction of risk of onset of dementia for African American men and women age 65 and older with hypertension when they take any of a variety of drug classes for their high blood pressure. These medications include beta blockers, ACE inhibitors, calcium channel blocks and diuretics.

The large study looked at the effects of antihypertensive treatment on the risk of dementia over a period of up to 24 years in 1262 older African Americans with high blood pressure who were cognitively normal at the onset of the study.

"Other research has looked at midlife hypertension as risk factor for dementia," said study corresponding author Michael D. Murray, PharmD, MPH of the Regenstrief Institute's Center for Health Services Research and Purdue University College of Pharmacy. "We have found even if African Americans control blood pressure when they are 65 and older the risk of dementia can be reduced.

"And we also can now pass along the useful information that you don't need to take the expensive new drugs on market. Older generic medications will work just as well in lowering risk of dementia and are less expensive."

In a previous work, the Regenstrief Institute researchers reported that antihypertensive medications had a protective effect, reducing the odds of cognitive impairment in older African Americans. The new study investigated the effect of antihypertensive medications on cognitive impairment and dementia, determining that it is blood pressure reduction rather than the medications that lower risk of dementia.

The most recent National Health and Nutrition Examination Survey indicates that a quarter of patients with hypertension were not receiving an antihypertensive medication.

"Controlling blood pressure is important for lowering risk of heart attack, stroke and kidney disease," Dr. Murray said. "We can now add prevention of dementia to the list of benefits of good blood pressure control at all ages. Preventing dementia is critical; once you start the decline from cognitive impairment to mild and eventually severe dementia there is no known cure."