Aging causes changes in the brain's white matter, which is worsened by hypertension and other vascular problems
Research Activities, April 2010, No. 356
All older adults show brain changes as they age. These include the shrinking of various brain regions as well as a decrease in cerebral white matter. As one grows older, along with these changes is an increased risk for vascular events, such as stroke. A new study has found a link between age-related brain changes and vascular risks, such as high blood pressure. Specifically, the increase in vascular risk exacerbates age-related declines in the brain.
Researchers studied brain changes in 77 healthy adults ranging in age from 19 to 84. The sample included men and women with and without high blood pressure. Nine white matter regions of the brain were examined using imaging techniques and measurements. The study found widespread reductions in white matter in the older individuals. Two areas of the brain most susceptible to such changes were the prefrontal and occipital regions.
Changes were most notable in individuals who were 55 years of age and older. However, the presence of vascular risk factors, such as hypertension, caused changes in white matter regardless of age. According to the researchers, as vascular risk increased, age-related damage in white matter also expanded from the anterior to the posterior regions of the brain. Selective deterioration of regional white matter may result in impaired connectivity among cortical brain-associated regions and contribute to the cognitive decline seen in aging, suggest the researchers. The aggressive treatment of high blood pressure and other vascular problems may help reduce the cognitive signs of aging in the brain caused by these changes. The study was supported in part by the Agency for Healthcare Research and Quality (HS13819).
See "Pattern of normal age-related regional differences in white matter microstructure is modified by vascular risk," by Kristen M. Kennedy, Ph.D., and Naftali Raz, Ph.D., in Brain Research 1297, pp. 41-56, 2009.