Smokers have a 45% higher risk of developing dementia than non-smokers, according to information published by the World Health Organization (WHO) in collaboration with Alzheimer's Disease International (ADI).

Evidence reviewed by WHO reveals a strong link between smoking and the risk of dementia, and the more a person smokes, the higher the risk. It is estimated that 14% of Alzheimer's disease cases worldwide are potentially attributable to smoking.

WHO warns that exposure to second-hand smoke (passive smoking) may also increase the risk of dementia.

"Since there is currently no cure for dementia, public health interventions need to focus on prevention by changing modifiable risk factors like smoking," says Dr Shekhar Saxena, Director of the Department for Mental Health and Substance Abuse at WHO. "This research shows that a decrease in smoking now is likely to result in a substantial decrease in the burden of dementia in the years to come."

Tobacco use is already recognized as the one risk factor common to four main groups of non-communicable diseases (NCDs): cancers, cardiovascular disease, chronic lung disease and diabetes.

"Tobacco is one of the biggest public health threats the world has ever faced, killing nearly six million people a year," says Dr Douglas Bettcher, Director of the Department for Prevention of Noncommunicable Diseases at WHO. "WHO urges governments to actively implement and enforce the measures of the WHO Framework Convention on Tobacco Control, especially smoke-free environment laws and access to tobacco cessation services".

Laurent Huber, Director of the Framework Convention Alliance (FCA) for Tobacco Control, comments: "It is no surprise to see these findings confirm that tobacco smoking is a major risk factor for dementia. This adds yet another item to the long list of the devastating consequences of tobacco and gives even more reason for personal and public health action to help people to quit smoking."

"The research also shows that quitting smoking later in life might be beneficial so encouraging and supporting current tobacco users to quit should be a priority," says Serge Gauthier, chair of the ADI's Medical Scientific Advisory Committee.

Dementia affects more than 44 million people worldwide, with almost two thirds of them living in low- and middle-income countries.

"Every year, there are 7.7 million new cases of dementia. In 2010, the global cost was calculated at US$ 604 billion, which represents 1% of global GDP (gross domestic product)," says Marc Wortmann, ADI Executive Director. "No government can ignore the opportunity to link this new information into its planning and health system activities to reduce smoking and control NCDs."

ADI believes that this information brief can form the basis for countries to add messages about brain health and dementia risk into public health anti-smoking programs and interventions.

For more information visit: http://www.who.int/tobacco/publications/en/