Norwegian Multiple Sclerosis Competence Centre and Research Group
New dissertation June 2021

The impact of lifestyle factors on disease risk and long-term disability progression in multiple sclerosis

Kristin Wesnes presented her dissertation for the Ph.D. degree with the thesis " The impact of lifestyle factors on disease risk and long-term disability progression in multiple sclerosis" on the 4th of June 2021.

Portrait of a young woman smiling.
Vegard Røine Stenerud

Main content

Can lifestyle factors such as smoking, degree of physical activity, overweight, and time spent inside have an effect on the progression of the neurological disease multiple sclerosis (MS)? Wesnes has in her thesis shown that being overweight and degree of physical activity can affect risk of developing MS, while low levels of vitamin D can result in a larger long term disease burden.

The first study is based on Norwegian and Italian data from a large survey-based multicenter study on lifestyle and environmental factors, the EnviMS-study. Participants marked out which body figure best matched their own at different ages. The results from the study showed that individuals with the most overweight body figures had an increased risk of developing MS as teenagers or young adults in the Norwegian cohort.

The second study is based on the same data, and looked in to light and heavy exercise among participants in Norway, Sweeden and Italy. Wesnes and associates found that more physical activity pr week in teenage years lowered the risk of developing MS in all countries and for both sexes. For light physical exercise there was no effect on the risk of MS.
The third study looked into the effects of vitamin D, tobacco use and body mass index (BMI) measured at several timepoints over a two-year period among 80 norwegian MS-patients. Analyses showed that higher levels of vitamin D gave less loss of function 10 years later, compared to those with lower levels. Low levels during spring had the most effect on function loss. Smoking and BMI did not affect the loss of function in this study, however this might be because many stopped smoking during the 10 years until follow up. Many also had a benign disease course.  

This thesis shows that lifestyle factors contribute to both risk of and longtime prognosis in MS. 


Kristin Wesnes (f.1981) finished medical studies at UiB in 2007 and is now consultant neurologist at St. Olavs hospital in Trondheim. She started this research project in 2012, and has since been a PhD-candidate at the Department of Neurology at Haukeland University Hospital and the Department of Clinical Medicine 1, UiB. Main supervisor was professor Kjell-Morten Myhr, co-supervisors were professor Trond Riise and research scientist Kjetil Bjørnevik.