Smoking increases dementia risk

The negative public health affect of smoking has the possibility to become even worse as the population around the world ages with the strong prevalence dementia. A new study, published today in the Archives of Internal Medicine, is the first to look at the consequences of heavy smoking during midlife on dementia.

Researchers at the University of Eastern Finland and at Kuopio University Hospital, Finland, studied data from 21,123 members of a health care system who participated in a survey between 1978 and 1985, when they were between ages 50 and 60.

Smoking is a scientifically proven risk factor for stroke, and could help increase the risk of vascular dementia in a similar manner, the authors wrote.

Study participants who reported smoking more than two packs a day during middle age had an higher risk of all the subtypes of dementia, compared to non-smokers, or those who smoked less than a half-pack a day, the researchers said in a statement.

While the research was observational, the researchers have theories about what could be going on, Whitmer says. “People who smoke have increased inflammation, and we know inflammation also plays a role in Alzheimer’s,” she says.

A total of 5,367 participants were diagnosed with dementia during an average of 23 years of follow-up, including 1,136 with Alzheimer’s disease and 416 with vascular dementia. The participants who smoked two packs of cigarettes a day increased their risk of getting Alzheimer’s by 157 percent.

Alzheimer’s, the most common form of dementia, is a fatal brain disease in which individuals slowly lose their memories and their abilities to reason and care for themselves. It impacts more than 26 million people worldwide.