Multiple sclerosis (MS) is a chronic degenerative and unpredictable condition that randomly attacks the brain and spinal cord. The symptoms vary greatly from person to person.
There is currently no cure, but treatments are available to modify the course of the disease and ease some symptoms.
The study, published in the `Annals of Neurology` journal, analysed a population-based cohort research involving 145 subjects with relapsing-remitting MS from 2002 to 2005.
Prof Bruce Taylor of the University of Tasmania, who led the study, said there is substantial evidence indicating increased levels of sun exposure and vitamin D are associated with a lower risk of MS onset, ie, a first attack.
"However, few factors have yet been identified that cause the onset of relapses in people already diagnosed with MS. We found that higher levels of vitamin D are associated with a reduced likelihood of a relapse in MS.
"The study demonstrates that for each 10nmol/l increase in serum vitamin D dosage, there was up to a 12 per cent reduction in the likelihood of a relapse. Clinically, raising vitamin D levels by 50nmol/l could halve the hazard of a relapse.
"Essentially, the study showed that people are more likely to have a relapse if they had low vitamin D levels.?
These findings provide strong support for randomised clinical trials of vitamin D-based therapies for treating relapses in MS sufferers," Prof Taylor said.