Vascular Abnormalities in Brain Linked to Shorter Life Span

THURSDAY, March 2, 2006 (HealthDay News) -- Large amounts of white matter in the brain, along with enlarged open areas filled with spinal fluid, appear to be linked to cardiovascular disease and shorter life spans for the elderly.

The findings raise the possibility that controlling blood pressure may need to take a greater role in the fight against cardiovascular disease and early mortality.

"It suggests that very tight control of blood pressure throughout life is a major determinant of longevity," said study author Dr. Lewis Kuller, a professor of epidemiology at the University of Pittsburgh's Graduate School of Public Health.

"We need to be more aggressive about treatment," added Dr. Jesse Weinberger, director of the neurovascular lab at Mount Sinai School of Medicine in New York City. The findings also fit nicely with existing information about how blood pressure affects different systems in the body, he added.

The research was presented Thursday at the American Heart Association's annual conference on Cardiovascular Disease Epidemiology and Prevention, in Phoenix.

"White matter" are the nerve fibers that carry messages from neurons, or the brain's nerve cells, to the rest of the body. The fluid-filled open areas in the brain are called ventricles. As a person ages, neurons are lost while ventricles get bigger.

Kuller and his colleagues had earlier shown that blood pressure and vascular disease are associated with dementia. Other researchers have shown that kidney function is a predictor of mortality and of heart attack and stroke. Experts have since been playing with the idea that damage to the small vessels in the kidney and brain as a result of high blood pressure are responsible for these connections.

The new study is part of the Cardiovascular Health Study, sponsored by the National Institutes of Health, which is looking at the factors relevant to cardiovascular disease.

More than 3,200 people, average age 75 at the time, underwent magnetic resonance imaging of the brain. They were subsequently followed for 12 years, the longest such follow-up ever. Sixty percent of the participants were women and 14.5 percent were black (who have a higher incidence of high blood pressure).

Each brain was given a "white matter grade" (WMG) from one to nine, and a ventricular grade (VG). During the 12 years of follow-up, mortality rose with increasing grades.

Women on the younger end of the spectrum (ages 65 to 74) who had a WMG of less than two had an overall death rate of 12.2 per 1,000, vs. 57.9 per 1,000 for those with a WMG greater than five.

Overall, participants who scored below the average on both scales had a 57 percent lower risk of death, compared to participants who scored above the average.

The white matter and ventricle scores also predicted the presence of cardiovascular disease.

The average survival of a 75-year-old participant with below-average scores and no cardiovascular disease was estimated to be almost 18 years, vs. 11.9 years for those with white matter grades and ventricular grades above the average plus early cardiovascular disease.

"It was an independent predictor of longevity," Kuller said.

While the findings do point to the need for more stringent blood pressure control and possibly for limiting dietary salt intake, more studies need to be done, he added.

"We need focusing on individuals at a younger age to see if we can prevent progression of cardiovascular disease," Kuller said. "We think a lot of disease and disability might be prevented by aggressive treatment of vascular disease. This is potentially preventable."

More information

The National Heart, Lung, and Blood Institute has more on lowering your blood pressure.