Level of education and multiple sclerosis risk after adjustment for known risk factors: The EnvIMS study

Kjetil Bjørnevik; Trond Riise; Marianna Cortese; Trygve Holmøy; Margitta T Kampman; Sandra Magalhaes; Kjell-Morten Myhr; Christina Wolfson; Maura Pugliatti

doi:10.1177/1352458515579444

Level of education and multiple sclerosis risk after adjustment for known risk factors: The EnvIMS study

Mult Scler. 2016 Jan;22(1):104-11. doi: 10.1177/1352458515579444. Epub 2015 May 26.

Authors

Kjetil Bjørnevik¹, Trond Riise², Marianna Cortese³, Trygve Holmøy⁴, Margitta T Kampman⁵, Sandra Magalhaes⁶, Kjell-Morten Myhr³, Christina Wolfson⁷, Maura Pugliatti⁸

Affiliations

¹ Department of Global Public Health and Primary Care, University of Bergen, Norway/The Norwegian Multiple Sclerosis Competence Center, Department of Neurology, Haukeland University Hospital, Norway kjetil.bjornevik@igs.uib.no.
² Department of Global Public Health and Primary Care, University of Bergen, Norway/The Norwegian Multiple Sclerosis Competence Center, Department of Neurology, Haukeland University Hospital, Norway.
³ The Norwegian Multiple Sclerosis Competence Center, Department of Neurology, Haukeland University Hospital, Norway/The KG Jebsen Centre for MS-Research, Department of Clinical Medicine, University of Bergen, Norway.
⁴ Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Norway/Department of Neurology, Akershus University Hospital, Norway.
⁵ Department of Clinical Neurology, University of Tromsø, Norway/Centre for Clinical Research and Education, University Hospital of North Norway, Norway.
⁶ Department of Epidemiology and Biostatistics and Occupational Health, McGill University, Canada.
⁷ Department of Epidemiology and Biostatistics and Occupational Health, McGill University, Canada/Research Institute of the McGill University Health Centre, Canada.
⁸ Department of Global Public Health and Primary Care, University of Bergen, Norway/Department of Clinical and Experimental Medicine, University of Sassari, Italy/Division of Medicine, McGill University, Canada.

Abstract

Background: Several recent studies have found a higher risk of multiple sclerosis (MS) among people with a low level of education. This has been suggested to reflect an effect of smoking and lower vitamin D status in the social class associated with lower levels of education.

Objective: The objective of this paper is to investigate the association between level of education and MS risk adjusting for the known risk factors smoking, infectious mononucleosis, indicators of vitamin D levels and body size.

Methods: Within the case-control study on Environmental Factors In MS (EnvIMS), 953 MS patients and 1717 healthy controls from Norway reported educational level and history of exposure to putative environmental risk factors.

Results: Higher level of education were associated with decreased MS risk (p trend = 0.001) with an OR of 0.53 (95% CI 0.41-0.68) when comparing those with the highest and lowest level of education. This association was only moderately reduced after adjusting for known risk factors (OR 0.61, 95% CI 0.44-0.83). The estimates remained similar when cases with disease onset before age 28 were excluded.

Conclusion: These findings suggest that factors related to lower socioeconomic status other than established risk factors are associated with MS risk.

Keywords: Multiple sclerosis; education; environmental risk factors; socioeconomic status.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Aged, 80 and over
Educational Status
Female
Humans
Infectious Mononucleosis / complications
Infectious Mononucleosis / epidemiology*
Male
Middle Aged
Multiple Sclerosis / epidemiology*
Multiple Sclerosis / etiology
Norway / epidemiology
Registries*
Risk
Risk Factors
Smoking / adverse effects
Smoking / epidemiology*
Social Class*
Vitamin D* / administration & dosage

Substances

Vitamin D