Zelia Chiu, Ming-Lee Lin, Cecilia Ling, Robyn Troutbeck, Xavier Fagan, Lyndell Lim, Anthony Hall
Purpose: There are links between autoimmunity and vitamin D deftciency. Vitamin D supplementa- tion is being trialled for some auto-immune dis- eases. Animal studies have demonstrated that calcitriol inhibits the development of experimental autoimmune uveitis (EAU), and has potential to reverse already-developed EAU; however few clini- cal studies exist. We therefore aim to investigate the relationship between serum vitamin D levels and uveitis activity.
Method: An observational case-control study recruiting patients with active and inactive non- infectious uveitis from two Victorian tertiary hospi- tals and private ophthalmic practice was performed. Patients were recruited between February and September 2017. All patients had a serum 25-hydro- xyvitamin-D measurement. Analysis was performed between active and inactive groups, and demographically-matched data from the ABS Nutri- tion Survey 2011-2012.
Results: 37 patients with active non-infectious uve- itis and 41 patients with inactive non-infectious uveitis were identifted, with a median age of 47. The median (IQR) level of serum vitamin D in active uveitis was 58nmol/L (34,74.5), signiftcantly lower than the inactive uveitis group at 66nmol/L (56,81) (p=0.0323). The active uveitis group was found to have lower serum vitamin D levels than ABS controls, who have a median (IQR) of 60nmol/L (44,67).
Conclusion: Patients with active uveitis have lower serum vitamin D levels than inactive controls. We postulate that low serum vitamin D levels predis- pose to uveitis activity; as we performed the serum vitamin measurement at the time of activity it is unlikely that the uveitis caused the low vitamin D levels. Further studies are recommended to deter- mine the efftcacy of vitamin D supplementation for uveitis.