Vitamin D supplementation in patients with vitamin D deficiency could be the key to prevent non-infectious uveitis.
Over the years, the impact of vitamin D intake and deficiency has been widely studied. The role vitamin D has always been deemed pivotal in countering inflammation and triggering the reactivity of the immune system.
Not surprisingly, previous data has suggested that vitamin D deficiency may be associated with a considerable increase in the risk of several eye diseases.
Investigators from several studies have stated that vitamin D supplementation could represent a possible therapeutic strategy for preventing or managing non-infectious uveitis, if substantiated. They also added that clinicians should consider screening for and addressing vitamin D deficiency in patients with or at risk of non-infectious uveitis.
Driven by an interest in exploring the topic further, a team of researchers led by William Rojas-Carabali, MD, of Nanyang Technological University, designed and launched the current research endeavour as a systematic review and meta-analysis of data from studies within the Embase, PubMed, and Lilacs databases.
Initially performed on 25 January 2022 and updated on 8 May 2023, the research returned more than 900 articles for screening, of which 11 were included in the systematic review and 5 were subject to meta-analysis. Among the 11 articles identified for inclusion, 6 were case-control studies, 2 were cohort studies and 3 were cross-sectional studies.
Overall, the data set obtained by researchers included information related to 354 cases of non-infectious uveitis and 5,728 control patients. The meta-analysis was based on 5 studies and included a total of 6,082 individuals with non-infectious uveitis.
The overall analysis showed that patients with non-infectious uveitis had significantly lower 25(OH)D levels in serum compared with controls (SMD, -0.39; 95% Confidence Interval [CI], -0.71 to -0.08; P =.0007) However, researchers drew attention to the substantial heterogeneity among the studies (I2=79%).
When only examining studies that measured vitamin D levels at any time prior to the onset of uveitis, results indicated that subjects who developed uveitis had significantly reduced vitamin D levels compared to the control group (SMD, -0.37; 95% CI, -0.56 to -0.17).
The research team, however, noted several limitations within their study for clinicians to consider, such as reliance on observational data, a relatively small sample size, and the inherent heterogeneity in data.
“Our results show that patients with hypovitaminosis D are 2.04 times more likely to develop non-infectious uveitis than subjects with vitamin D sufficiency,” the researchers added. “However, these conclusions are based on limited data from a few studies, suggesting that further research in this field is necessary. In future investigations, authors should standardise the measurement technique and cut-off values of serum vitamin D to reduce heterogeneity in meta-analysis.”
References:
1. Rojas-Carabali W, Pineda-Sierra JS, Cifuentes-González C, et al. Vitamin D deficiency and non-infectious uveitis: A systematic review and Meta-analysis. Autoimmun Rev. Published online December 3, 2023. doi:10.1016/j.autrev.2023.103497 2. Pillar S, Amer R. The association between vitamin D and uveitis: A comprehensive review. Surv Ophthalmol. 2022;67(2):321-330. doi:10.1016/j.survophthal.2021.07.
