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Multiple Sclerosis 40% more likely in obese than in overweight (Mendelian randomization) Jan 2018

Mendelian randomization in multiple sclerosis: A causal role for vitamin D and obesity?

Multiple Sclerosis Journal, January 8, 2018
Adil Harroud, J Brent Richards

VitaminDWiki

Not a surprise

  • Obese have lower levels of vitamin D
  • Lower level of vitamin D (for any reason) increases the risk of Multiple Sclerosis

Items in both categories Multiple Sclerosis and Obesity are listed here:

 Download the PDF from VitaminDWiki

The etiology of multiple sclerosis (MS) involves a complex interplay of genetic and environmental factors. Epidemiologic studies have furthered our understanding of these risk factors but remain limited by residual confounding and potential for reverse causation, particularly in MS where time of disease onset is not known. Mendelian randomization (MR) uses genetic variants to study the causal effect of modifiable exposures on an outcome. This method avoids some of the limitations of classical epidemiology and can strengthen causal inference. Here, we introduce the basic concepts of MR and review its contributions to the field of MS. Indeed, several studies using MR have now provided support for a causal role for low vitamin D level and obesity in the development of MS.

Table 1. Limitations of MR and how to address them

Image

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Created by admin. Last Modification: Saturday January 13, 2018 11:17:40 UTC by admin. (Version 6)

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9171 MS MR Table 1.jpg admin 13 Jan, 2018 11:11 84.57 Kb 9
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