Seasonal variability of vitamin D status in patients with inflammatory bowel disease - A retrospective cohort study.
Christine Elisabeth JanssenAnna-Maria GlobigAndrea Busse GrawitzDominik BettingerPeter HasselblattPublished in: PloS one (2019)
Vitamin D deficiency was highly prevalent in patients with Crohn's disease and ulcerative colitis and dependent on the season of the year. Following normalization for seasonality by sinusoidal regression analysis, vitamin D deficiency was found to be associated with parameters of complicated disease course while increasing 25(OH)D concentrations over time correlated with reduced activity of Crohn's disease.