The incidence of Alzheimer's disease is on the rise, with one in eight people 65 and older diagnosed with the disease. Unless methods for preventing or controlling the disease are found, the number of cases of Alzheimer's will increase as the older population increases. Exercise is emerging as a possible preventive measure and is a realistic step every person can take.
Identification of Alzheimer's Disease
Alzheimer's is a degenerative brain disease causing memory loss as well as deterioration of social skills, intellect and problem-solving abilities. The progression is usually slow, but eventually the problems interfere with daily life. The disease afflicts about 5 percent of people between 65 and 74 years old. For people 85 years and older, the incidence is 50 percent. Onset of Alzheimer's can occur as early as the 40s or 50s.
Causes
According to the Alzheimer's Association, there is no known cause for Alzheimer's, although scientists have defined risk factors linked to the disease. Age is the greatest known risk factor, as most patients who are diagnosed are over 65 years old. Genetics may also play a role, with many people carrying a genetic marker for Alzheimer's, but this does not predict the onset of the disease. Patients who've experienced a head injury are at higher risk for Alzheimer's, and there is also a link between heart disease and the development of Alzheimer's.
Effects of Exercise
Exercise reduces the risk of cardiovascular disease and may directly affect the brain by increasing blood flow and oxygen saturation. In a study conducted at Washington University in St. Louis, 69 adults ages 55 to 88 were found to have normal cognition and then were asked to fill out a questionnaire about their physical activity over the previous 10 years. Cerebrospinal fluid and brain imaging tests were performed to look for the biomarkers of Alzheimer's. The researchers found that participants who had exercised regularly in the previous 10 years had lower levels of plaque buildup as well as lower levels of tau, a marker for neural dysfunction, than more sedentary participants. The results revealed there may be a connection between exercise and Alzheimer's biomarkers in adults.
Expert Insight
The director of the Alzheimer's Research Center at the Mayo Clinic, Dr. Ronald Petersen, said in an ABC interview in 2008, "Regular physical exercise is probably the best means we have of preventing Alzheimer's disease today, better than medications, better than intellectual activity, better than supplements and diet." A randomized study published in "The Archives of Neurology" suggested that exercise was a viable alternative to some medicinal therapies for women who were at high risk for mental decline.
Considerations
Many factors determine whether or not someone will develop Alzheimer's. The Alzheimer's Association suggests people adopt an overall healthy lifestyle, for example by maintaining a healthy weight, avoiding tobacco and refraining from excess alcohol; keep emotional and social connections; and engage in exercise for the mind and body.
References
- Mayo Clinic: Alzheimer's disease
- Alzheimer's Association: What is Alzheimer's
- Alzheimer's Association: Risk Factors
- Alzheimer's Association: Prevention
- Mayo Clinic: Can exercise prevent memory loss and improve cognitive function?
- "Annals of Neurology"; Exercise and Alzheimer's disease biomarkers . . . ; Liang et al; August, 2010
