Moderate exercise may stall vascular dementia

NEW YORK (Reuters Health) - Older adults who regularly walkfor exercise may help lower their risk of vascular dementia,the second-most common form of this disorder after Alzheimer'sdisease, a study published Wednesday suggests.
In a group of 749 adults who were 65 years of age or older,the Italian researchers found that those who regularly walkedor got other forms of moderate exercise were less likely todevelop vascular dementia over the next 4 years.
Compared with their sedentary counterparts, active adultshad about one quarter the risk of developing vascular dementia.Vascular dementia is caused by an impaired blood flow to thebrain. Blockages that narrow the blood vessels supplying thebrain or complete blockages that cause a stroke, may also leadto vascular dementia. People with conditions that damage bloodvessels throughout the body -- such as high blood pressure ordiabetes -- are also at increased risk.
The new findings, published in the online edition of thejournal Neurology, build on evidence that lifestyle habits areimportant in dementia risk. A number of studies have suggestedthat the same habits that are good for the heart -- such as ahealthy diet and regular exercise -- may benefit the agingbrain as well.
Although moderate exercise had no effect on Alzheimer'sdisease, the findings do not mean that exercise has no effecton the risk of Alzheimer's, according to the researchers, ledby Dr. Giovanni Ravaglia of the University Hospital S.Orsola-Malpighi in Bologna.
The study included Italian adults with no evidence ofmental decline at the outset. The patients were interviewedabout their physical activity levels, medical history and anydepression symptoms, among other health factors.
Over the next 4 years, 86 study participants were diagnosedwith dementia, including 27 with vascular dementia.
Ravaglia's team found that, compared with participants whowalked the least often at the study's start, those who loggedthe most miles were 73-percent less likely to develop vasculardementia.
Similarly, those who got the most moderate exercise of anytype -- such as gardening, bicycling and housework -- had a 76percent lower risk of vascular dementia.
Exercise may benefit mental functioning for a number ofreasons, according to the researchers. Aside from improvingblood from improving the blood flow to the brain, it may alsostimulate the release of key brain chemicals, and enhance thedevelopment of new nerve cells or the connections among thosecells.
It's also possible, Ravaglia and his colleagues note, thatan active lifestyle helps protect the aging brain by keepingolder adults mentally stimulated and socially active.
In general, experts advise that all healthy adults try toaccumulate at least 30 minutes of moderate exercise on most, ifnot all, days of the week. Older adults who want to start a newexercise routine should talk with their doctors first.
SOURCE: Neurology, online December 19, 2007.