Treating hypertension could cut the annual number of bleeding strokes in the United States by about one-fourth, according to a report in today’s rapid access issue of Stroke: Journal of the American Heart Association
“We estimate that 17 percent to 28 percent of hemorrhagic strokes among hypertensive patients would have been prevented if they had been on hypertension treatment,” said lead author Daniel Woo, M.D., assistant professor of neurology at the University of Cincinnati. However, even when treated, high-blood pressure remains a significant risk factor for hemorrhagic strokes.
Woo and his colleagues found that the risk for hemorrhagic stroke among people with untreated hypertension was 3.7 times greater than that for the general population in and around Cincinnati. The risk for the treated hypertension patients was 1.4 times higher.
Hemorrhages cause about 20 percent of all strokes. They include two basic types: intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). ICH occurs when a blood vessel ruptures inside the brain. SAH results from bleeding into the space between the brain and the lining that surrounds it.
About half of people who have a hemorrhagic stroke die. Many survivors are left with paralysis and other debilitating effects.
Researchers studied 549 patients treated for stroke between May 1997 and December 2002 at 16 hospitals within a 50-mile radius of the University of Cincinnati and compared them to age, race and gender-matched controls. Among their other findings:
Untreated hypertension patients had a 4.4-fold greater risk of ICH and the risk for treated patients was l.6 times higher than the control group.
Among SAH patients, the untreated group had a risk three-fold that of the controls. The untreated patients had a statistically insignificant risk of 1.1 times higher.
Women were more likely than men to be treated for hypertension.
Blacks were less likely to be treated for hypertension than nonblacks. However, after controlling for insurance status, there was no significant difference in the untreated rate of blacks and nonblacks.
Co-authors are Mary Haverbusch, R.N.; Padmini Sekar, M.S.; Brett Kissela, M.D.; Jane Khoury, M.S.; Alexander Schneider, M.D.; Dawn Kleindorfer, M.D.; Jerzy Szaflarski, M.D., Ph.D.; Arthur Pancioli, M.D.; Edward Jauch, M.D.; Charles Moomaw, Ph.D.; Laura Sauerbeck, R.N.; James Gebel, M.D.; and Joseph Broderick, M.D.