Bergen Multiple Sclerosis Research Group
Body size and risk of MS

New study: Body size and the risk of multiple sclerosis in Norway and Italy: The EnvIMS study.

Researchers at the KGJ Centre for MS Research have published an article in Multiple Sclerosis Journal on obesity as an risk factor for MS.

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Obesity may be a risk factor for developing multiple sclerosis (MS).


We examined if body size influences the risk of MS in a population-based, case control study.


A total of 953 cases and 1717 controls from Norway and 707 cases and 1333 controls from Italy reported their body size by choosing a silhouette 1 to 9 (largest) every fifth year from age 5 to 30 and at time of study. The body size-related MS risk was defined by odds ratios (ORs) in logistic regression analyses adjusting for age, smoking and outdoor activity.


In Norway a large body size (silhouettes 6-9) compared to silhouette 3 increased the risk of MS, especially at age 25 (OR 2.21; 95% CI 1.09-4.46 for men and OR 1.43; 95% CI 0.90-2.27 for women). When comparing silhouette 9 to 1, we found a significant dose-response from age 10 until age 30 peaking at age 25 (sex-adjusted OR 2.83; 95% CI 1.68-4.78). The association was present for at least 15 years prior to disease onset. No significant associations were found in Italy.


Obesity from childhood until young adulthood is a likely risk factor for MS with a seemingly stronger effect in Norway than in Italy.



Wesnes K, Riise T, Casetta I, Drulovic J, Granieri E, Holmøy T, Kampman MT, Landtblom AM, Lauer K, Lossius A, Magalhaes S, Pekmezovic T, Bjørnevik K, Wolfson C, Pugliatti M, Myhr KM. Body size and the risk of multiple sclerosis in Norway and Italy: The EnvIMS study. Mult Scler. 2014 Sep 2. pii: 1352458514546785. [Epub ahead of print]