OBJECTIVE: There is increasing evidence that vitamin D can be protective against the development of MS, but it may also be beneficial for the clinical course of the disease. The objective was to prospectively investigate if 25-hydroxy-vitamin D (25-OH-D) levels are associated with exacerbation risk in MS in a study with frequent serum measurements.
METHODS: This was a prospective longitudinal study in 73 MSers with relapsing-remitting MS. Blood samples for 25-OH-D measurements were taken every 8 weeks. Associations between 25-OH-D levels and exacerbation rates were assessed using Poisson regression (generalized estimating equations) with the individual serum levels as time-dependent variable.
RESULTS: During follow-up (mean 1.7 years), 58 MSers experienced a total of 139 exacerbations. Monthly moving averages of 25-OH-D levels were categorized into low (<50 nmol/L), medium (50-100 nmol/L), and high (>100 nmol/L) levels. Exacerbation risk decreased significantly with higher serum vitamin D levels: respective relative exacerbation rates for the medium and high-level category as compared to the low-level category were 0.7 and 0.5 (p value for trend: p = 0.007). The association between 25-OH-D concentrations and exacerbation rate was log linear without a threshold. With each doubling of the serum 25-OH-D concentration the exacerbation rate decreased by 27% (95% confidence interval 8%-42%, p = 0.008).
CONCLUSIONS: The finding that higher vitamin D levels are associated with decreased exacerbation risk in relapsing-remitting MS suggests a beneficial effect of vitamin D on disease course in MS. However, the possibility of reverse causality cannot be ruled out completely. Randomized intervention studies are therefore needed to investigate the effect of vitamin D supplementation in MS.
They say, in the UK testing Vit D costs £45 (if your GP will do the test and If their pathlab will accept testing it to start with) and currently it is rather unlikely you or your GP would be able to get more than 1 test on the NHS, even for a follow up of treatment.
"However, the possibility of reverse causality cannot be ruled out completely."Which means that low vitamin D levels could be the RESULT of high frequency of relapses, since a relapse usually makes patients stay at home or get hospitalised, away from sunlight.
Re: "They say, in the UK testing Vit D costs £45."It costs less than this; I suspect this is the price of it being done in the private sector. Because of the problem with poor diet and poor sunshine the most cost-effective use of resource is to go onto supplements for 6-8 weeks and then test to make sure you are taking sufficient.
Re: "Which means that low vitamin D levels could be the RESULT of high frequency of relapses, since a relapse usually makes patients stay at home or get hospitalised, away from sunlight."More likely to be the consumption of vD by the immune response. Th17 cells are particularly hungry when it comes to vD; according to immunologists they eat the stuff all day. They only way to sort this out is to do a randomised, double-blind, controlled trial correcting for baseline and follow-up vD levels.