Would a vitamin D treatment be viable for all types of MS?

There are three general disease patterns that may be classified as MS phenotypes. Upon initial onset of the disease, the majority of patients^[1] will be classified as relapsing-remitting multiple sclerosis (RRMS). Disease progression between periods of relapse is usually minimal, although the attacks themselves can cause a person to become more disabled.

Secondary progressive multiple sclerosis is usually seen as an initial RRMS diagnosis, but unlike RRMS, these patients will see a gradual worsening of symptoms (some of which are shown in Figure 3) with or without relapses. The third pattern, primary progressive multiple sclerosis, is a steady increase in disability from disease onset and has the worst prognosis. This accounts for about 10% of MS cases^[2] from initial diagnosis. While vitamin D supplementation may be a viable treatment option for all of these MS subtypes, the efficacy is not well understood. Current and pending trials are primarily looking at people with RRMS, as it is the most common diagnosis.

Reference: Richards et al. Health Technol Assess. 2002.