Introduction
The objective of this study was to determine whether serum vitamin D [25(OH)D] levels are associated with disease progression in amyotrophic lateral sclerosis (ALS).
Methods
25(OH)D was measured in subjects enrolled in a multicenter study for validation of ALS biomarkers. Baseline 25(OH)D levels were correlated with baseline ALSFRS‐R scores. Average 25(OH)D levels from baseline and month 6 visits (seasonally asynchronous) were used to predict subsequent rate of change in ALSFRS‐R from month 6 to month 18.
Results
Most subjects had either insufficient or deficient 25(OH)D levels. Lower 25(OH)D was associated with lower ALSFRS‐R gross motor scores, but not lower ALSFRS‐R total scores at baseline. Levels of 25(OH)D were not predictive of disease progression over the next 12 months.
Conclusion
25(OH)D was associated with baseline gross motor ALSFRS‐R scores but did not predict the rate of disease progression. Vitamin D levels may reflect poor mobility in patients with ALS. Muscle Nerve, 2017 Muscle Nerve 56: 726–731, 2017