We’ve long known that exercise is great preventive medicine, but we generally think of it in terms of curbing the risk of cardiovascular disease, diabetes or even cancer. Now, in one of the first studies of its kind, researchers have found that physical fitness also lowers the risk of dementia-related death.
While cardiovascular and cancer deaths are on the decline, deaths from dementia and Alzheimer’s are on the rise. According to the study’s authors, deaths related to dementia increased by 46 percent between 2002 and 2006 alone. And some of that may have to do with fitness: lead researcher Rui Liu — a fellow at the National Institute of Environmental Health Sciences at the NIH — and her team found that being out of shape more than doubled the risk of dying from a dementia-related cause.
The study results linked to above were published in Medicine & Science in Sport and Exercise. This journal is a publication of the American College of Sports Medicine. Researchers studied some 60,000 subjects (46,000 males and over 14,000 females) between the ages of 20 and 88. These subjects were followed for 17 years. The basic measurement tool used to determine the level of physical fitness was the Cardio-Respiratory Fitness (CRF) scale. Most of the subjects were educated, middle class and white. Stated in plain English the researchers found that people with high CRF scores were less than half as likely to die of causes related to dementia and Alzheimer’s disease.
The researchers stress that they did not find a “cause and effect” relationship between a high CRF score and low incidence of death from dementia-related diseases. They did find a statistically significant link between the two. Researchers point out that the CRF scores used did not rely on self-reported levels of physical activity among the subject. Baseline data was collected in 1986 at the Cooper Clinic in Dallas. By 2003 some 4047 subjects had died; according the National Death Index 164 died from vascular dementia or Alzheimer’s.
When researchers matched the records for the deceased to their CRF scores they found that 123 were in the “low fit” category; 18 were in the “medium fit” category and 23 were in the “high fit” category. Being in the “low fit’ category at every age more than doubled the chance of dying from dementia or Alzheimer’s.
In some ways these findings support what is already known—cardiovascular health improves the blood flow to all organs in the body, including the brain. This is consistent with another a recent study from the Journal of Neurology that found running and walking helped minimize arterial plaque build-up and, in turn, helped study participants score better on tests of memory and mental acuity.
Readers who want to read a more complete report on this study can click on the following link to take them to the Huffington Post: http://www.huffingtonpost.com/2012/02/07/exercise-prevents-dementia_n_1260122.html.