Study confirms link between MS and smoking cigarettes

While smoking cigarettes appears to significantly increase a person’s risk of developing multiple sclerosis (MS), using Swedish snuff does not, according to a study published in the September print issue of the American journal Neurology. This could mean that that nicotine is not the substance responsible for the increased risk of MS among smokers.

The study involved 902 people diagnosed with MS and 1,855 people without MS in Sweden between the ages of 16 and 70. All participants answered a questionnaire about tobacco cigarettes and snuff use.

The Karolinska Institutet research team found that in women who smoked, the risk for developing MS was nearly one and a half times higher than in women who did not smoke. In men, the risk was nearly two times higher in those who smoked compared to those who did not smoke. This was the case even in people who only smoked moderately.

An interesting observation made by the researchers, was that using Swedish snuff did not increase the risk of developing MS. This could mean that nicotine is not the substance responsible for increased risk of MS among smokers, as Swedish snuff also contains nicotine.

- However more research is needed to better understand the mechanisms behind the findings. Theories are that smoking may raise the risk of MS by increasing the frequency and persistence of respiratory infections, or by causing autoimmune reactions in genetically susceptible people, says study coordinator Anna K Hedström.

Publication

Anna K Hedström, Maria Bäärnhielm, Tomas Olsson, Lars Alfredsson

Neurology - the medical journal of the American Academy of Neurology, 1 September 2009, print issue