Sun Exposure, Vitamin D Intake and Progression to Disability among Veterans with Progressive Multiple Sclerosis

Abstract

Background: Early life events have been suggested to influence multiple sclerosis (MS) susceptibility, and to potentially modulate its clinical course. We assessed vitamin D-related exposures from childhood to disease onset and their associations with MS progression. Methods: Among veterans in the Multiple Sclerosis Surveillance Registry, 219 reported having the progressive form and met the inclusion criteria. Participants reported their past sun exposure, vitamin D-related intake and age at disability milestones using the Patient-Determined Disease Steps (PDDS). The Cox proportional hazards model was used to examine the association between vitamin D-related exposures and time (years) to disability. Results: Low average sun exposure in the fall/winter before disease onset was associated with an increased risk of progressing to a PDDS score of 8 (hazard ratio, HR: 2.13, 95% confidence interval, CI: 1.20–3.78), whereas use of cod liver oil during childhood and adolescence was associated with a reduced risk (HR: 0.44, 95% CI: 0.20–0.96). Conclusions: These results suggest that exposure to vitamin D before MS onset might slow disease-related neurodegeneration and thus delay progression to disability among patients with the progressive subtype.

Can we prevent or treat multiple sclerosis by individualised vitamin D supply?

“…Likewise, several methodically high quality studies showed an inverse association between sun exposure or outdoor activities during childhood and adolescence, and the risk of developing MS during adulthood [86-90]. In line with these reports is the recent observation that low sun exposure in fall/winter before disease onset was associated with a less favourable outcome [91]. Yet, all these studies have two major intrinsic limitations: first, despite a reported reasonable validity and reliability [92], the retrospective determination of sun exposure years or even decades in the past is inevitably subjected to recall bias [34], and prospective studies are hardly available.…”

A randomised, double blind, placebo controlled trial with vitamin D3as an add on treatment to interferon β-1b in patients with multiple sclerosis

“…The study found that a low average sun exposure before disease onset increased the risk to disease progression whereas use of cod liver oil during childhood delayed progression 27. We did not measure brain atrophy and followed disability accumulation for only 1 year.…”

“…Recently, a study based on patient reported previous sun exposure, vitamin D intake and age at disability milestones from 219 veterans with progressive forms of MS in the Multiple Sclerosis Surveillance Registry was published 27. The study found that a low average sun exposure before disease onset increased the risk to disease progression whereas use of cod liver oil during childhood delayed progression 27.…”

A Randomised, Double-Blind, Placebo-Controlled Trial with Vitamin D3 in MS: Subgroup Analysis of Patients with Baseline Disease Activity Despite Interferon Treatment

“…Most recently, researchers correlated each 10 nmol/L increase in 25(OH)D with up to 12% reduction in relapse rate in adults with MS [6], and each 25 nmol/L increase in 25(OH)D with a 34% decrease in relapse rate in pediatric-onset MS [7]. Other researchers have correlated greater early sun exposure and vitamin D intake with a reduced risk of progression to severe disability in veterans with MS [8], and lower 24,25-dihydroxyvitamin D (24,25(OH) 2 D) with higher Expanded Disability Scale (EDSS) and higher 25(OH)D to 24,25(OH) 2 D ratio with lower brain parenchymal fraction in patients with MS [9]. A one-year randomized controlled vitamin D3 dose escalation study (mean intake ~14,000 IU/day), although not powered to detect clinical outcomes, nevertheless found that the proportion of patients experiencing relapses was lower in the vitamin D3-supplemented group than in the control group [10].…”