Smokers More Likely to Develop Dementia
Tuesday, September 4, 2007; 12:00 AM
TUESDAY, Sept. 4 (HealthDay News) -- Current smokers are 50 percent more likely to develop Alzheimer's disease or dementia than people who don't smoke or who gave up smoking, a Dutch report says.
Researchers announced these results after analyzing seven years of data from almost 7,000 people over age 55.
Over the course of the study, 706 people developed dementia. People who were smokers during the study were 50 percent more likely to develop dementia than people who had never smoked or were former smokers, according to the researchers, who published their findings in the Sept. 4 issue ofNeurology.
"Smoking increases the risk of cerebrovascular disease, which is also tied to dementia," study author Dr. Monique Breteler, of Erasmus Medical Center in Rotterdam, the Netherlands, said in a prepared statement. "Another mechanism could be through oxidative stress, which can damage cells in the blood vessels and lead to hardening of the arteries. Smokers experience greater oxidative stress than nonsmokers, and increased oxidative stress is also seen in Alzheimer's disease."
Oxidative stress occurs when there are too many waste products from chemical reactions in the body. Dietary antioxidants can fight those waste products, known as free radicals, but Breteler said that smokers are also known to have fewer antioxidants in their diets than nonsmokers.
The researchers also studied the way that smoking affects the risk of Alzheimer's disease for people who carry the related gene. They found that smoking did not increase the risk for those with the gene for Alzheimer's disease, but it did increase the risk for people without the gene. Current smokers without the gene were 70 percent more likely to develop Alzheimer's disease than nonsmokers or former smokers without the gene.