Wednesday, 23 January 2013

Vitamin A and the Risk of MS

#MSBlog: Does systemic inflammation in childhood protect you from MS? The hygiene hypothesis.

EpubSalzer et al. Vitamin A and systemic inflammation as protective factors in multiple sclerosis. Mult Scler. 2013 Jan.

BACKGROUND: Vitamin A is important for the immune system, and might suppress inflammatory activity in MS.

OBJECTIVES: This study aimed to examine if vitamin A levels were associated with MS risk in samples collected prospectively and during gestation.

METHODS: The investigators measured Retinol Binding Protein (RBP - a surrogate marker for vitamin A) and high-sensitivity C-reactive protein (hs-CRP) levels, in (1) prospectively collected biobank blood samples from MS cases and controls, and (2) gestational samples where the offspring had later developed MS, and gestational control samples. The risk of MS was calculated using matched multivariable logistic regression adjusted for confounders.

RESULTS: In prospective samples, RBP levels within the second quintile (vs. the first) were associated with a lower MS risk (OR = 0.38, 95% CI 0.19-0.74). No effect on MS risk in the offspring by gestational RBP levels was found. In young subjects hs-CRP levels ≥10 mg/l in prospective samples were associated with a lower MS risk (OR = 0.36, 95% CI 0.14-0.95).

CONCLUSIONS: Our results suggest that sub-optimal vitamin A levels may be associated with MS risk. The association between hs-CRP levels and MS risk in young subjects may support the role of the hygiene hypothesis in MS aetiology.

Vitamin A Deficiency seems to occur in areas of low MS prevalence!

"This studies conclusions are premature; all biomarkers need exploratory and validation cohorts. Why was the 2nd quintle or 5th of subjects at lowere risk and not the 3rd, 4th, or 5th? There is no dose effect! Therefore this observation is likely to have occurred by chance. The high levels of CRP, an inflammatory marker, predicting a lower risk is interesting. CRP tends to go up with infections. The author's suggest that this is due to infection and hence a hyperactive immune system that is associated with a lower risk of MS. The claim that this is due to the hygiene hypothesis. Maybe! I am not convinced. Overall this study asks more questions than it answers."

1 comment:

Please note that all comments are moderated and any personal or marketing-related submissions will not be shown.