Treating blood pressure may help prevent dementia

Treating high blood pressure in the very elderly may help reduce their risk of developing dementia, researchers said on Monday.

Blood pressure treatment in the over-80 set has already been shown to reduce risk of heart problems and fatal strokes.

"There may be an additional benefit in terms of prevention of dementia," said Dr. Ruth Peters of Imperial College London, whose study appears in the journal Lancet Neurology.

The findings are based on a new analysis of a study of nearly 4,000 people that was among the first to show the benefit of offering treatment for high blood pressure to people over 80, a group often overlooked in medical studies.

That study found patients whose high blood pressure was treated with a diuretic, with or without a second blood pressure drug called an ACE inhibitor, had a reduced risk of death from stroke and death from any cause.

Several studies have found a link between high blood pressure and dementia, which is marked by a loss of memory and other cognitive abilities, including the ability to speak, identify objects or think abstractly.

The latest analysis looks at whether treatment of high blood pressure helped to stave off dementia.

Participants had no clinical diagnosis of dementia at the start of the trial. Their cognitive function was assessed at the start and then each subsequent year with a standard test called the mini-mental state examination.

The trial was halted early because death and stroke rates had fallen so much it would have been unethical not to offer blood pressure medication to everyone in the study.

Out of the 3,336 people who had at least one follow-up assessment, about half had drug treatment and half had a placebo. What Peters' team found was people who got blood pressure treatment had slightly lower rates of dementia, but the finding was not statistically significant.

But, when the researchers added results from this study to three similar studies in what is known as a meta-analysis, the combined results showed reducing blood pressure cut the risk of developing dementia from any cause by 13 percent.

Peters said in an e-mail the findings may be significant given demographic trends.

"Anything that can help reduce dementia incidence is important," Peters said. "The population of the elderly is growing. The very elderly are the fastest-growing section of the elderly and at high risk from dementia," she said.

Because treatment for high blood pressure has already been shown to help reduce the risk of strokes and heart problems, any reduction in dementia would be an added benefit, she said.

More than 5 million Americans have Alzheimer's disease, the most common form of dementia, accounting for 60 to 80 percent of cases. The second most common form is vascular dementia, which is often caused by strokes.