Myasthenia gravis patients appear to have lower levels of vitamin D than the general population, a study confirmed.
The confirmation suggested that doctors need to monitor patients’ vitamin D levels to reduce the chance they will have additional autoimmune responses that can worsen their condition, the researchers said.
Their study, “Low serum vitamin D levels in patients with myasthenia gravis,” appeared in the Journal of Clinical Neuroscience.
Vitamin D plays an important roles in regulating the immune system, studies have shown.
A team of researchers decided to look at the relationship between vitamin D levels and the severity of myasthenia gravis.
They measured levels of the two major forms of the vitamin — 25-hydroxyvitamin D [25(OH)D] and 1,25-dihydroxyvitamin D [1,25(OH)2D] — in 25 myasthenia gravis patients and 40 healthy controls.
The patients were producing anti-acetylcholine receptor (AChR) autoantibodies.
Researchers classified the patients by their disease stage, the severity of their condition, whether they had the general or ocular form of myasthenia gravis, whether they had developed the disease early or late, and whether they were taking immunosuppressive agents. The disease is considered early-onset if it occurs before the age of 50 and late-onset if it occurs afterward.
Patients producing anti-AChR antibodies had significantly lower levels of the 25(OH)D form of vitamin D than controls, but the same levels of the 1,25(OH)2D form, researchers discovered.
The results were in agreement with those of a previous study, the team said.
“Although four patients taking immunosuppressive agents had insufficient levels of 25(OH)D, there is no significant difference in 25(OH)D levels between patients under only symptomatic therapy and immuno-suppressive agents,” the researchers wrote.
They also found no correlation between vitamin D levels, the severity of patients’ disease and whether they developed it early or late.
Overall, “serum vitamin D levels were lower in AChR-MG patients compared with age- and sex-matched healthy controls,” the team wrote. “We recommend the monitoring of vitamin D levels in patients with AChR-MG,” they added.
“Although we did not evaluate the clinical effects of vitamin D supplementation, further prospective studies are needed to elucidate the role of vitamin D supplementation in patients with MG [myasthenia gravis],” the team concluded.