Researchers in the Netherlands surveyed 364 people at both the initial and secondary stages of MS, 263 of whom were smokers.
The study showed there is no association between cigarette smoking and the progression of MS. Due to the high number of smokers with MS, it had previously been suggested there was a correlation between the progression of the disease related to smoking.
"Because the cause of MS as well as reasons for progression is generally unknown, there have been many genetic and environmental factors tested," said study author Marcus W. Koch, MD, with the University of Groningen in the Netherlands. "Cigarette smoking is one more factor we can rule out."
Koch says the finding is in conflict with a previous study that suggested cigarette smoking increased the rate of MS progress. "Differences in that study's size and methodology may account for this discrepancy. Since our study involved more people, and participants were personally interviewed, we feel it makes our results more accurate."