To investigate the association of dose-dependent vitamin d supplement on clinical outcomes in veterans with multiple sclerosis

Objective: To investigate the association of daily dose-dependent Vitamin-D supplement on clinical outcomes including mortality in veterans with multiple sclerosis (MS) with low serum Vitamin-D (25[OH]D) levels. This Methods: observational, longitudinal study reports on data collected from 1/1/2000 to 12/31/2020 at the MS Regional Program. We reviewed the electronic records of 163 veterans with MS who were followed every four months in our MS clinic. The study sample was divided into three groups based on the daily Vitamin-D supplement doses: low (1000 IU/day), medium (2000 IU/day) and high (4000 IU/day). The clinical outcomes were changes in physical disability (Expanded Disability Severity Scale (EDSS)), function (Total Function Independence Measures (TFIM)), time-to-event EDSS score of 6 (progressive MS) and mortality. Results: There were 32 patients in the low, 46 in the medium, and 85 in the high-dose daily Vitamin-D supplement groups. The mean age of the entire study sample was 51 12 SD years (range 23 - 79 years). The mean duration of MS was 21.7 13 years. The mean initial EDSS and TFIM scores were 3.4 2.8 and 111 17 SD. At entry, mean serum 25[OH]D and calcium levels were 30 16 nmol/l and 9.3 0.4. The risk of MS-related progressive disability (time-to-event EDSS score 6) was lower and there were fewer deaths in the high- (compared to low- and medium-) dose groups. Conclusion: This study suggests that among veterans with MS and low 25[OH]D levels, those who received high-doses daily of supplemental Vitamin-D supplement were associated with a decreased risk of MS-related progressive disability and death than those who received a lower dose. No adverse clinical or biochemical events were noted.