April 16, 2008 -- People who smoke a pack of cigarettes or more a day develop Alzheimer's disease years earlier than those who do not, and heavy drinking of alcohol increases the risk even more.
In what is being lauded as a significant finding, research presented at the American Academy of Neurology's 60th Anniversary Annual Meeting this week in Chicago shows that smoking and drinking are among the most important preventable risk factors for Alzheimer's disease.
Researcher Ranjan Duara, MD, of the Wien Center for Alzheimer's Disease at Mount Sinai Medical Center in Miami Beach, Fla., found that a combination of heavy drinking and heavy smoking leads to an earlier onset of Alzheimer's disease.
"It has been projected that a delay in the onset of the disease by 5 years would lead to a nearly 50% reduction in the total number of Alzheimer's cases," Duara says in a news release. "If we can reduce or eliminate heavy smoking and drinking, we could substantially delay the onset of Alzheimer's disease for people and reduce the number of people who have Alzheimer's at any point in time."
Duara's study involved 938 people aged 60 and older with possible or probable Alzheimer's. Family members provided information regarding the patients' alcohol consumption and cigarette usage.
Heavy smoking was defined as one or more packs of cigarettes a day; heavy drinking was defined as more than two drinks per day. The researchers also grouped participants according to whether they carried the apolipoprotein E-4 [ApoE-4] gene variant, which increases risk for Alzheimer's disease.
The study showed:
- Heavy drinkers developed the disease 4.8 years before those who did not drink as much.
- Alzheimer's developed 2.3 years earlier in heavy smokers than in those who were not heavy smokers.
- The gene variant reduced the age of onset by three years.
- People with all three risk factors developed Alzheimer's 8.5 years earlier than those who had no risk factors.
Alzheimer's disease is a progressive, incurable brain disease that leads to the loss of mental abilities that affect memory and learning. According to the Alzheimer's Association, about 5 million people in the U.S. live with the condition. However, there are concerns that the number will skyrocket in the near future as America's baby boomers reach their golden years.