Serum Vitamin D Levels in Patients with Acute Anterior Uveitis

Vitamin D Supplementation and Remission from Chronic Anterior Uveitis

PURPOSE

Chronic anterior uveitis (CAU) often requires suppressive therapy, which has potential side effects including cataract, ocular hypertension, and increased risk of infection. No remittive therapy is currently available; however, several studies have demonstrated an association between low 25-hydroxy Vitamin D (25OHD) levels and either uveitis incidence or uveitis disease activity. This study investigates the potential of Vitamin D supplementation as a remittive treatment for CAU.

METHODS

We conducted a retrospective analysis using data from the Systemic Immunosuppressive Therapy for Eye Disease (SITE) cohort study, which included patients with ocular inflammatory disease seen at U.S. tertiary centers between 1979 and 2010. Vitamin D supplementation data was analyzed for patients with CAU. Eyes were considered in remission if they remained quiet for at least 90 days off all anti-inflammatory treatment for eye disease.

RESULTS

Among 2688 patients who never used Vitamin D, the cumulative adjusted CAU remission incidence was 13.5% at the 16-month follow-up. In contrast, among 75 patients who used Vitamin D for a duration of ≤1 year, the cumulative adjusted CAU remission incidence was 28% at 16 months. The use of Vitamin D was associated with a crude hazard ratio for remission of 2.14 [95% confidence interval (CI) 1.23-3.71, p = 0.0071], and an adjusted hazard ratio for remission of 2.43 [95% CI: 1.36-4.33, p = 0.0027].

CONCLUSION

In the SITE Cohort, Vitamin D supplementation is associated with a significantly increased incidence of remission. Vitamin D supplementation should be explored in a prospective trial as the next step of evaluation.

Vitamin D Levels in Patients with Noninfectious Uveitis: A Systematic Review and Meta-Analysis

PURPOSE

Vitamin D deficiency has been associated with higher rates of autoimmune disease, including noninfectious uveitis. This PRISMA-compliant review and meta-analysis aimed to analyze the correlation between noninfectious uveitis and vitamin D levels.

METHODS

We searched PubMed, Embase, Cochrane, and Web of Science databases for studies, published in English, assessing vitamin D levels in patients diagnosed with noninfectious uveitis. The outcomes of interest were vitamin D deficiency, vitamin D mean level, vitamin D supplementation, and smoking rates. A subgroup analysis of inactive uveitis and active uveitis was performed. The heterogeneity was assessed with Cochrane Q-test and I2 statistics; p > 0.10 and I2 > 50% were considered significant for heterogeneity. Statistical analysis was conducted using Review Manager 5.3.

RESULTS

9 studies were included in the meta-analysis comprising a total of 10 711 patients, of whom 1,368 were diagnosed with noninfectious uveitis. Patients with noninfectious uveitis had worse results regarding vitamin D deficiency when compared with the control group (OR 0.58; CI 95% 0.44 to 0.77; p = 0.0002; I2 = 61%). Patients with inactive uveitis had better results towards vitamin D deficiency when compared with active uveitis (OR 5.00; CI 95% 2.84 to 8.81; p < 0.001; I2 = 0%).

CONCLUSION

Our research supports the increasing evidence that associates vitamin D deficiency with noninfectious uveitis and its activity. Further investigation into the efficacy of vitamin D screening and supplementation in reducing the recurrence of uveitis is necessary.

Serum Vitamin D Levels as Biomarkers in Patients with Autoimmune Uveitis and their Possible Correlation with Disease Activity

This study investigated the correlation between serum vitamin D levels and intraocular inflammation in patients with autoimmune uveitis (AIU). We evaluated 67 patients with active and inactive AIU and measured their serum 25-hydroxyvitamin D [25(OH)D] concentration, sun exposure habits, number of relapses, and complications. Of the patients evaluated, 85% had significantly lower vitamin D levels, and patients with active uveitis had lower 25(OH)D levels than those with inactive uveitis. The odds of developing active uveitis decreased by 6% with each 1-unit increase in 25(OH)D. Patients with recurrent active AIU had significantly lower 25(OH)D serum levels than inactive forms, indicating that low vitamin D levels may alter the clinical course of intraocular inflammation in AIU. Additionally, the study found that a higher mean BMI increased the chances of an individual having active uveitis by 14%. These results suggest that serum vitamin D concentration could be a prognostic clinical biomarker in AIU.

Vitamin D deficiency and non-infectious uveitis: A systematic review and Meta-analysis

BACKGROUND

Vitamin D plays a critical role in immunomodulation, and its deficiency is implicated in the pathogenesis of several autoimmune diseases. Nevertheless, its relationship with non-infectious uveitis (NIU), an inflammatory ocular disorder, remains inconclusive.

METHODS

A systematic search was conducted in three databases from database inception until May 8, 2023, to investigate the potential relationship between vitamin D deficiency and NIU. We included observational studies reporting the measurement of vitamin D levels in patients with NIU and healthy controls without restriction of language or date of publication. Three pairs of authors independently screened the title and abstracts for potential eligibility and then in full text. A third author resolved disagreements. Three pairs of independent reviewers abstracted the data from the fully reviewed records and evaluated the risk of bias. We followed The MOOSE and PRISMA guidelines. Random effects meta-analyses were used for primary analysis. Studies not included in the meta-analysis were summarized descriptively. This review was registered in PROSPERO: CRD42022308105.

FINDINGS

Of 933 records screened, 11 studies were included, and five were meta-analyzed, encompassing 354 cases and 5728 controls (mean participant age ranging from 7.1 to 58.9 years). Patients with vitamin D deficiency exhibited an Odds Ratio of 2.04 (95% CI = 1.55-2.68, P < 0.00001) for developing NIU compared to controls. Overall, potential sources of bias were low across most studies.

INTERPRETATION

Our findings suggest that vitamin D may play an essential role in the pathophysiology of NIU. While the included studies demonstrated generally low potential bias, additional rigorous prospective studies are necessary to confirm these findings and further elucidate the underlying mechanisms involved. Vitamin D supplementation could represent a possible therapeutic strategy for preventing or managing NIU if substantiated. Clinicians should consider screening for and addressing vitamin D deficiency in patients with or at risk for NIU.

Mendelian Randomization Shows a Causal Effect of Low Vitamin D on Non-infectious Uveitis and Scleritis Risk

PURPOSE

To investigate a causal relationship between Vitamin D levels and non-infectious uveitis and scleritis using Mendelian randomization (MR) techniques.

DESIGN

Two-sample Mendelian randomization case-control study.

METHODS

The study setting was a biobank of an academic, integrated health care system. The patient population comprised 375 case patients with a non-infectious uveitis and/or scleritis diagnosis and no diagnosis of infectious, trauma-related, or drug-induced uveitis/scleritis. In addition, there were 4167 controls with no uveitis or scleritis diagnosis. Causal effect estimates of low 25-hydroxy Vitamin D (25OHD) on uveitis/scleritis risk were calculated.

RESULTS

We found an association of genetically decreased 25OHD with uveitis/scleritis risk (odds ratio [OR] = 2.16, 95% CI = 1.01-4.64, P = .049, per SD decrease in log25OHD). In a first sensitivity MR analysis excluding the genetic variants that are unlikely to have a role in biologically active 25OHD, effect estimates were consistent with those from the primary analysis (OR = 2.38, 95% CI =1.06-5.36, P = 0.035, per SD of log25OHD). Furthermore, in a second sensitivity analysis using only the 6 variants within the CYP2R1 locus (which encodes 25OHD hydroxylase, the liver enzyme responsible for converting Vitamin D to 25OHD), genetically decreased 25OHD was strongly associated with increased uveitis/scleritis risk (OR = 6.42, 95% CI = 3.19-12.89, P = 1.7 × 10^-7, per SD of log25OHD).

CONCLUSIONS

Our findings suggest a causal relationship between low Vitamin D levels and higher risk of non-infectious uveitis and scleritis. Vitamin D supplementation may be a low-cost, low-risk intervention to mitigate non-infectious uveitis and scleritis risk, and should be explored in a prospective trial.

Vitamin D, the Vitamin D Receptor, Calcitriol Analogues and Their Link with Ocular Diseases

The global prevalence of eye diseases continues to grow, bringing with it a reduction in the activity levels and quality of life of patients, and partial or complete blindness if left untreated. As such, there is considerable interest in identifying more effective therapeutic options and preventive agents. One such agent is vitamin D, known to have a range of anti-cancer, anti-angiogenic, anti-inflammatory and anti-oxidative properties, and whose deficiency is linked to the pathogenesis of a range of cardiovascular, cancer, and inflammatory diseases. This review presents the current stage of knowledge concerning the link between vitamin D and its receptor and the occurrence of eye disease, as well as the influence of analogues of calcitriol, an active metabolite of vitamin D. Generally, patients affected by various ocular disorders have vitamin D deficiency. In addition, previous findings suggest that vitamin D modulates the course of eye diseases and may serve as a marker, and that its supplementation could mitigate some disorders. However, as these studies have some limitations, we recommend further randomized trials to clarify the link between vitamin D and its activity with eye disease.

Vitamin D and Ocular Diseases: A Systematic Review

The contributory roles of vitamin D in ocular and visual health have long been discussed, with numerous studies pointing to the adverse effects of vitamin D deficiency. In this paper, we provide a systematic review of recent findings on the association between vitamin D and different ocular diseases, including myopia, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), dry eye syndrome (DES), thyroid eye disease (TED), uveitis, retinoblastoma (RB), cataract, and others, from epidemiological, clinical and basic studies, and briefly discuss vitamin D metabolism in the eye. We searched two research databases for articles examining the association between vitamin D deficiency and different ocular diseases. One hundred and sixty-two studies were found. There is evidence on the association between vitamin D and myopia, AMD, DR, and DES. Overall, 17 out of 27 studies reported an association between vitamin D and AMD, while 48 out of 54 studies reported that vitamin D was associated with DR, and 25 out of 27 studies reported an association between vitamin D and DES. However, the available evidence for the association with other ocular diseases, such as glaucoma, TED, and RB, remains limited.

Epidemiology and Risk Factors in Non-infectious Uveitis: A Systematic Review

Purpose: Non-infectious uveitis is a leading cause of vision loss in the developed world. The purpose of this systematic review is to investigate the epidemiology and risk factors of non-infectious uveitis over the last 50 years.

Methods: A systematic literature search of Pubmed/MEDLINE database was performed in the 50-year period from January 1971 to January 2021, according to the PRISMA guidelines. Studies that assessed the epidemiology and risk factors for non-infectious uveitis were included.

Results: Few epidemiologic studies focus specifically on non-infectious uveitis. In the Unites States, the estimated prevalence of non-infectious uveitis is 121/100,000. The incidence and prevalence varies considerably worldwide. Females and the working age group (20–50 years) appear to be the most affected. Smoking and vitamin D deficiency are the biggest risk factors for non-infectious uveitis, while pregnancy appears to be protective. Additional risk factors include presence of other autoimmune diseases (thyroid disease, diabetes, celiac), pre-eclampsia/eclampsia, psychological stress, and certain medications (bisphosphonates, immune checkpoint inhibitors, female hormone therapy, and etanercept).

Discussion: Our systematic review summarizes the incidence and prevalence of non-infectious uveitis and associated modifiable and non-modifiable risk factors.

The association between vitamin D and uveitis: A comprehensive review

Vitamin D plays an important role in both the innate and adaptive immune systems. We review published data on the relationship between uveitis and vitamin D levels or vitamin D-associated gene polymorphisms. A search of the PubMed and Medline databases was conducted to identify relevant articles concerning vitamin D and uveitis. Sixteen studies were included in this review, and the evidence they present, linking low vitamin D levels with uveitis, is compelling. The uveitic entities shown to be modulated by hypovitaminosis D include, but are not limited to, HLA-B27-associated acute anterior uveitis, Vogt-Koyanagi-Harada (VKH) disease, sarcoidosis-associated uveitis, and juvenile idiopathic arthritis-associated uveitis. Specific polymorphisms of vitamin D family genes were found to correlate with uveitis in ankylosing spondylitis, Behçet's disease, VKH, and HLA B27-positive patients. Further understanding of the role of vitamin D, a known regulator of inflammatory processes, in noninfectious uveitis may advance capabilities in the fields of disease prevention and treatment.

Vitamin D deficiency is associated with COVID-19 positivity and severity of the disease

The present study examined the relationship between polymerase chain reaction (PCR) test positivity and clinical outcomes of vitamin D levels measured within the 6 months before the PCR test in coronavirus disease 2019 (COVID‐19)‐positive patients. In this retrospective cohort study, COVID‐19 (227) and non‐COVID‐19 patients (260) were divided into four groups according to their vitamin D levels: Group I (0–10 ng/ml), Group II (10–20 ng/ml), Group III (20–30 ng/ml), and Group IV (vitamin D > 30 ng/ml). Laboratory test results and the radiological findings were evaluated. In addition, for comparative purposes, medical records of 1200 patients who had a hospital visit in the November 1, 2019–November 1, 2020 period for complaints due to reasons not related to COVID‐19 were investigated for the availability of vitamin D measurements. This search yielded 260 patients with tested vitamin D levels. Vitamin D levels were below 30 ng/ml in 94.27% of 227 COVID‐19‐positive patients (average age, 46.32 ± 1.24 years [range, 20–80 years] and 56.54% women) while 93.07% of 260 non‐COVID‐19 patients (average age, 44.63 ± 1.30 years [range, 18–75 years] and 59.50% women) had vitamin D levels below 30 ng/ml. Nevertheless, very severe vitamin D deficiency (<10 ng/ml) was considerably more common in COVID‐19 patients (44%) (average age, 44.15 ± 1.89 years [range, 23–80 years] and 57.57% women) than in non‐COVID‐19 ones (31%) (average age, 46.50 ± 2.21 years [range, 20–75 years] and 62.5% women). Among COVID‐19‐positive patients, the group with vitamin D levels of  >30 ng/ml had significantly lower D‐dimer and C‐reactive protein (CRP) levels, number levels, number of affected lung segments and shorter hospital stays. No difference was found among the groups in terms of age and gender distribution. Elevated vitamin D levels could decrease COVID‐19 PCR positivity, D‐dime and CRP levels and the number of affected lung segments in COVID‐19‐positive patients, thereby shortening the duration of hospital stays and alleviating the intensity of COVID‐19.

Association of Hypovitaminosis D With Increased Risk of Uveitis in a Large Health Care Claims Database

Importance

Understanding the role of vitamin D-which regulates inflammatory responses-in noninfectious uveitis (an inflammatory disease) may provide insight into treatment and prevention of this disease.

Objective

To investigate whether there is an association between hypovitaminosis D and incident noninfectious uveitis.

Design, Setting, and Participants

In a retrospective case-control study, data from a health care claims database containing deidentified medical claims from a large private insurer were used to identify 558 adults enrolled from January 1, 2000, to December 31, 2016, who received a diagnosis of noninfectious uveitis from an eye care clinician (with receipt of a confirmatory diagnosis within 120 days of the initial diagnosis) and who had a vitamin D level measured within 1 year before the first diagnosis. Exclusion criteria included having systemic disease or receiving medication known to lower vitamin D levels, having undergone intraocular surgery, and having infectious uveitis. Each case patient was matched with 5 controls on the basis of age, sex, race/ethnicity, and index date (2790 controls). The controls had vitamin D level determined either within 1 year before or within 6 months after receiving an eye examination with normal findings. Multiple logistic regression models were used to examine the association between hypovitaminosis D and noninfectious uveitis.

Main Outcomes and Measures

The primary, prespecified analysis assessed the association of noninfectious uveitis with hypovitaminosis D (vitamin D level ≤20 ng/mL).

Results

The 558 cases and 2790 controls were matched on age, and each group had a mean (SD) age of 58.9 (14.7) years. Among the cohort of 3348 patients, 2526 (75.4%) were female, and the racial/ethnic distribution in the matched samples was 2022 (60.4%) white, 552 (16.5%) black, 402 (12.0%) Hispanic, 162 (4.8%) Asian, and 210 (6.3%) unknown. Patients with normal vitamin D levels had 21% lower odds of having noninfectious uveitis than patients with low vitamin D levels (odds ratio [OR], 0.79; 95% CI, 0.62-0.99; P = .04). In a race-stratified analysis, an association between vitamin D and uveitis was found in black patients (OR, 0.49; 95% CI, 0.30-0.80; P = .004) and was qualitatively similar but nonsignificant in white patients (OR, 0.87; 95% CI, 0.62-1.21; P = .40) and Hispanic patients (OR, 0.60; 95% CI, 0.33-1.10; P = .10).

Conclusions and Relevance

This and other reports have found an association between hypovitaminosis D and noninfectious uveitis. However, these studies cannot establish a causal relationship. Prospective studies are warranted to evaluate whether hypovitaminosis D causes increased risk of uveitis and the role of vitamin D supplementation in prevention and treatment of uveitis.

Patterns of Vitamin D Levels and Exposures in Active and Inactive Noninfectious Uveitis Patients

PURPOSE

To compare serum vitamin D levels and patterns of ultraviolet light and dietary exposure among patients with active and inactive noninfectious uveitis and population controls.

DESIGN

Prospective case-control study. All participants (n = 151) underwent serum 25-hydroxy vitamin D measurement and completed a questionnaire on vitamin D intake and ultraviolet light exposure. Serum 25-hydroxy vitamin D levels were compared between active and inactive uveitis groups and with local population estimates.

PARTICIPANTS

Adult patients with active and inactive noninfectious uveitis were recruited from 2 Victorian tertiary hospitals and 1 private ophthalmic practice.

METHODS

Serum 25-hydroxy vitamin D levels were compared between patients with active and inactive uveitis and population-based estimates of serum 25-hydroxy vitamin D levels, stratified by geographic region and season. Vitamin D intakes and exposures based on questionnaire results, including vitamin D supplementation and sunlight exposures on weekdays and weekends, were compared between active and inactive uveitis groups.

MAIN OUTCOME MEASURES

Serum vitamin D levels, intake of vitamin D, and exposure to sources of vitamin D.

RESULTS

The median level of serum vitamin D in those with active uveitis (n = 74) was 46 nmol/l (interquartile range [IQR], 29-70 nmol/l), significantly lower than in the inactive control group (n = 77) at 64 nmol/l (IQR, 52-79 nmol/l; P < 0.001). The active uveitis group also showed lower median serum vitamin D levels than the local population median of 62 nmol/l (IQR, 46-77 nmol/l). Vitamin D supplementation also was associated significantly with uveitis inactivity (P = 0.026, Kendall's τ test). In a subanalysis of vitamin D-deficient participants, sun exposure was associated significantly with uveitis inactivity (P = 0.014 for weekday and weekend analyses).

CONCLUSIONS

Participants with active uveitis showed significantly lower serum 25-hydroxy vitamin D levels than inactive uveitis patients and local population-based estimates. Vitamin D supplementation was found to be associated with decreased uveitis activity, as was sun exposure in those with vitamin D deficiency. These results suggest that vitamin D supplementation should be studied as an option for the prevention of uveitis relapse in at-risk patients.