Writing on his blog on Wednesday, University of Louisville professor Brad Rodu said the research, published in the International Journal of Epidemiology, had combined data from seven Swedish cohort studies involving nearly 350,000 men. The subjects were classified according to tobacco use and diagnosis of Parkinson’s disease over an average 16 years of follow-up.
Rodu said the principal results were impressive. Among never-tobacco smokers, Parkinson’s disease risk in ever-snus users was lower than in never-users.
Current-snus use was associated with a lower Parkinson’s disease risk than was former use.
And there was evidence of dose-response relationships.
The bottom line, Rodu said, was that current snus use, not former use, was strongly protective against Parkinson’s disease, with more protection from heavier and long-term use.
This is not the first such finding. In 2009, Rodu discussed research from the American Cancer Society showing a similar strong protective effect.
‘Further, Parkinson’s may not be the only nerve illness for which smokeless tobacco and/or nicotine use is protective,’ Rodu said.
Snus users had a significantly lower risk for multiple sclerosis than did non-users of tobacco.
Nicotine had been found to improve performance in people with mild cognitive impairment, and it might also benefit those with Alzheimer’s disease.
Rodu said that the current study represented a new era in Swedish snus research conducted by the Swedish Collaboration on Health Effects of Snus Use.
He said he hoped that the Swedish Collaboration, with investigators from multiple universities in Sweden and beyond, would produce valuable, unbiased research on the health impact of snus use.
Rodu’s annotated blog is at: http://rodutobaccotruth.blogspot.co.uk/