Smokers are more likely to develop dementia

September 4, 2007

People who smoke are more likely to develop Alzheimer’s disease or dementia than nonsmokers or those who smoked in the past, according to a study published in the September 4, 2007, issue of Neurology.

The study followed nearly 7,000 people age 55 and older for an average of seven years. Over that time, 706 of the participants developed dementia. People who were current smokers at the time of the study were 50 percent more likely to develop dementia than people who had never smoked or past smokers.

Smoking could affect the risk of dementia through several mechanisms, according to study author Monique Breteler, MD, PhD, of Erasmus Medical Center in Rotterdam, the Netherlands, and member of the American Academy of Neurology.

“Smoking increases the risk of cerebrovascular disease, which is also tied to dementia,” Breteler said. “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 the body has too many free radicals, which are waste products produced by chemical reactions in the body.

“Antioxidants in the diet can eliminate free radicals, and studies have shown that smokers have fewer antioxidants in their diets than nonsmokers,” Breteler said.

The researchers also looked into how smoking affects the risk of developing Alzheimer’s disease for people who have the gene that increases the risk of Alzheimer’s, called apolipoprotein E4, or APOEå4. They found that smoking did not increase the risk of Alzheimer’s for those with the APOEå4 gene. But for those without the APOEå4 gene, smoking increased the risk of Alzheimer’s. Current smokers without the Alzheimer’s gene were nearly 70 percent more likely to develop Alzheimer’s than nonsmokers or past smokers without the Alzheimer’s gene.

Source: American Academy of Neurology

Explore further: Alzheimer's starts earlier for heavy drinkers, smokers

Related Stories

Alzheimer's starts earlier for heavy drinkers, smokers

April 16, 2008

Heavy drinkers and heavy smokers develop Alzheimer’s disease years earlier than people with Alzheimer’s who do not drink or smoke heavily, according to research that will be presented at the American Academy of Neurology ...

Gene variations alter risk of esophageal cancer

November 5, 2008

Variations in a common gene pathway may affect esophageal cancer risk, a dangerous and rapidly increasing type of cancer, according to research by scientists at The University of Texas M. D. Anderson Cancer Center.

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

( -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.