Vitamin D Replacement Improves Tear Osmolarity in Patients with Vitamin D Deficiency

Serum Vitamin D Levels and Dry Eye Disease in Postmenopausal Women: A Case-Control Study at a Tertiary Care Center in Rural Haryana

Background

Despite the high prevalence of Vitamin-D insufficiency and high susceptibility to dry eye disease (DED) in postmenopausal women (PMW), correlation between DED and Vitamin D has not been explored in PMW in any Indian study.

Aims and Objectives

To explore the correlation between serum Vitamin D levels in PMW with and without DED, in a hospital-based population in rural Haryana.

Materials and Methods

Subjective (ocular surface disease index [OSDI] questionnaire) and objective clinical tests were undertaken for DED diagnosis. 25(OH) Vitamin D was measured in serum using enzyme-linked immunosorbent assay; insufficient (10-30 ng/ml) and deficient (<10 ng/ml). Descriptive statistics were analyzed by mean ± standard deviation for continuous and frequencies for the categorical variables; Student's t-test used to find out mean difference in Vitamin D levels; P < 0.05 was considered statistically significant.

Results

One hundred and forty PMW (60.1 ± 5.32 years) were included; Group-A (Controls; no DED; n: 70); Group-B (Cases; DED diagnosed by OSDI scores; n: 70); Subgroup-B1 (clinical tests negative; n: 30) and B2 (clinical tests positive; n: 40). There was no statistically significant difference in OSDI scores between B1 and B2. Significantly lower mean Vitamin D levels were found in cases (14.36 ± 4.08 ng/ml) as compared to controls (19.19 ± 6.4 ng/ml) (P = 0.001) and in B2 (13.15 ± 3.51 ng/ml) as compared to B1 (15.57 ± 4.66 ng/ml) (P = 0.01).

Conclusion

There were significantly low levels of Vitamin-D in clinically established DED. Evaluating Vitamin D levels as a part of the dry eye workup in PMW is recommended. OSDI scores were not aligned with the clinical test scores; questionnaire-based tests alone may not be sufficient for diagnosing DED.

Dry Eye Disease: What Is the Role of Vitamin D?

Dry eye disease (DED) is a multifactorial condition resulting from reduced tear secretion from the lacrimal glands, increased tear water evaporation or the production of poor-quality tears. Such tear instability can lead to inflammation and damage of the ocular surface, as well as to abnormal nociception. Historically, tear substitutes and corticosteroids have been the bastion of DED therapy, but a substantial number of patients still suffer from residual symptoms even after being treated with traditional treatments. Aiming to find safe and effective alternative therapies, recent efforts have been focused on the role of vitamin D in the cellular physiology of the eye. Possibly because of its positive effect in modulating the immune and inflammatory responses, the systemic supplementation of vitamin D seems, indeed, to be an effective therapeutic strategy, especially, but not only, for patients affected by DED that does not respond to conventional treatments. In this context, this review focuses on the literature reporting on the pathogenesis and treatment of DED, with a special emphasis on the recent investigations reporting on the potential role of the systemic administration of vitamin D as a therapeutic approach in the management of such condition.

Changes in Tear Meniscus Analysis of Children Who Have Type 1 Diabetes Mellitus, With and Without Vitamin D Deficiency

PURPOSE

The aim of this study was to quantitatively evaluate dry eye test parameters of pediatric patients with and without vitamin D deficiency (VDD) in type 1 diabetes mellitus.

METHODS

In this prospective cross-sectional study, the Ocular Surface Disease Index, Schirmer test, tear film breakup time, corneal staining score, and anterior segment optical coherence tomography were used to determine the dry eye test parameters of pediatric patients with type 1 diabetes mellitus (T1-DMPs) (group 1) and a healthy pediatric control group (group 2). Group 1 was divided into 2 subgroups based on their vitamin D status: group 1a, who had a VDD, and group 1b, who had vitamin D levels that were within the normal range.

RESULTS

This study compared 90 eyes of 90 pediatric T1-DMPs with 80 eyes of 80 healthy controls. The demographic characteristics of the groups were similar ( P > 0.05). The tear film breakup time, Schirmer test, corneal staining score, and values of the tear meniscus height and area were observed to have been lower in the patients in group 1a than the healthy pediatric control group, at P < 0.001. The same parameters were statistically significantly lower in the patients in group 1a when compared with group 1b ( P < 0.05 for both).

CONCLUSIONS

The tear measurements of the pediatric T1-DMPs were lower than those in the healthy pediatric control group. The accompanying VDD made this situation more pronounced.

The role of Vitamin D3 in ocular fibrosis and its therapeutic potential for the glaucomatous trabecular meshwork

Glaucoma is the leading cause of irreversible blindness globally. The most prevalent subtype, Primary Open Angle Glaucoma (POAG), is characterized by increased intraocular pressure (IOP), damage to the optic nerve head and irreversible visual loss. IOP increases aqueous humor (AqH) outflow is reduced through the trabecular meshwork (TM) and Schlemm's canal (SC). Increased outflow resistance is partly due to TM/SC dysregulation, including loss of normal trabecular meshwork cell (TMC) function, following increased levels of oxidative stress within TMC, dysregulated extracellular matrix (ECM) deposition and remodeling alongside alterations in TMC phenotype and apoptosis. Current widely available POAG treatments do not target the aberrant expression of ECM in the TM directly. As a result, most drug treatments can fail as the underlying pathological process continues unabated. Rho-kinase inhibitors have demonstrated the benefit of restoring TM/SC function, however there is a clear need to develop further treatment strategies that can target the underlying cellular processes which become dysregulated within the TMC during POAG pathogenesis. Vitamin D is suggested to be beneficial in alleviating the symptoms of fibrosis and inflammation in soft tissues. It has important functions in many major organ systems, including regulation of calcium, phosphate and parathyroid hormone. Evidence suggests that Vitamin D3 modulates ECM turnover through the conventional TGFβ-SMAD signaling, which is associated with the development of POAG. The link between Vitamin D3, inflammation and fibrosis within ocular tissues will be discussed and the potential roles of Vitamin D3 in the management of POAG patients will be explored within this review.

Conjunctival Histopathological Changes in Children With Vitamin D Deficiency

PURPOSE

The aim of this study was to investigate tear function-associated clinical findings and conjunctival histopathological changes in children with vitamin D (Vit-D) deficiency.

METHODS

This study used a prospective case-control design. Group 1 (n=38) comprised pediatric patients with Vit-D deficiency, and group 2 (n=45) was the control group. Tear break-up times (TBUTs), Schirmer-1 test measurements, ocular surface disease index (OSDI) scores, and conjunctival impression cytology (CIC) results of the groups were compared.

RESULTS

The participant demographic characteristics, including the mean age and the male-to-female ratio, were similar (P>0.05). The median TBUT and Schirmer-1 test measurement were 10 s (5-15) and 12 mm (6-19) in group 1 and 11 s (6-16) and 15 mm (8-21) in group 2 (P=0.004 and P=0.013, respectively). The median OSDI scores were 16 (10-20) in group 1 and 17 (10-21) in group 2 (P=0.092). According to the CIC, 25 samples in group 1 and 40 samples in group 2 were categorized as grade 0, 11 samples in group 1 and 5 samples in group 2 were categorized as grade 1, and 2 samples in group 1 and no sample in group 2 were categorized as grade 2 (P=0.027).

CONCLUSION

Significant conjunctival histopathological changes occur in children with Vit-D deficiency, and these changes have effects on some tear function-associated clinical findings including the Schirmer-1 test and TBUT measurements.

Oral vitamin D3 supplementation for femtosecond LASIK-associated dry eye vitamin D for LASIK dry eye syndrome

PURPOSE

To assess the effect of oral vitamin D₃ supplementation in dry eye after femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

SETTING

Liuzhou Worker's Hospital.

DESIGN

This prospective study included 90 patients selected between January and December in 2019, who underwent FS-LASIK operation in our hospital and had obvious symptoms indicating dry eyes 1 month after operation. The subjects were randomly divided into two groups: The experimental group (n = 45) received vitamin D3 2000 IU/D continuously for 12 weeks; the control group (n = 45) did not take vitamin D3 orally. Ocular surface disease index (OSDI), Tear breakup time (TBUT) and Schirmer's test I were evaluated premedication and 1,3,6 months after treatment. Serum vitamin D3 level and the mean concentration of cytokine IL-6, IL-17, IL-23 in t ears were also measured.

RESULTS

One month after treatment, the mean OSDI score of the experimental group (11.67 ± 8.53) was significantly lower than that of the control group (23.82 ± 13.22) (P = 0.007). TBUT (10.71 ± 1.02 s) and Schirmer I (9.36 ± 0.40 mm) of the experimental group were higher than those of the control group (7.49 ± 1.29 s and 7.51 ± 0.44 mm). The OSDI (10.25 ± 5.49) was significantly lower than those of the control group(20.22 ± 6.23) and TBUT (10.75 ± 1.09 s) and Schirmer I test value (11.34 ± 0.39 mm) of the experimental group were significantly higher than those of the control group (8.36 ± 1.23, 8.12 ± 0.50) at 3 months after treatment. There were significant differences in OSDI, TBUT (P < 0.05) and Schirmer I test value between the two groups at 6 months after treatment. Serum vitamin D₃ level was negatively correlated with OSDI score (r = - 0.90; P = 0.00) and positively correlated with Schirmer I test (r = 0.88; P = 0.00), TBUT score (r = 0.89; P = 0.00) and TMH (r = 0.80; P = 0.00). IL-17 level was shown to be significantly correlated with TBUT(r = - 0.25, P = 0.014) and Schirmer I test (r = - 0.21, P = 0.018). IL-6 level was significantly correlated with OSDI (R = 0.18, P = 0.020) and TBUT (R = 0.20, P = 0.019).

Dry Eye Disease and Vitamins: A Narrative Literature Review

Dry eye disease (DED) is a major public health problem worldwide that seriously impairs the quality of life, reduces work productivity, and poses significant economic burden. In DED, tear film instability or hyperosmolarity activates a self-perpetuating vicious cycle that may aggravate ocular surface inflammation and damage. Thus, treatment approaches should focus on interrupting this cycle and ameliorating inflammation. In addition to anti-inflammatory medications, such as corticosteroids, cyclosporine, and lifitegrast, nutrients with anti-inflammatory and anti-oxidative properties may also be effective for the treatment of DED. Evidence indicates that vitamin deficiencies may be associated with an increased risk of DED and that vitamin supplementation can be an effective treatment for DED. In the present review, we introduce the results of clinical and experimental studies on the association between vitamin deficiencies and DED. The potential efficacy of systemic and topical supplementation in the treatment of DED is also discussed.

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.

Effect of oral vitamin D supplementation on dry eye disease patients with vitamin D deficiency

CLINICAL RELEVANCE

Dry eye disease (DED) and vitamin D deficiency are both common clinical entities. Vitamin D has been reported to play a significant role in ocular surface homeostasis.

BACKGROUND

This study aimed to determine the therapeutic effect of oral vitamin D supplementation in dry eye disease patients with vitamin D deficiency.

METHODS

A randomized, controlled study was completed in 100 patients with dry eye disease and concurrent vitamin D deficiency (< 20 ng/ml). Participants were randomly allocated to 8 weeks of oral vitamin D supplementation with both groups receiving conventional dry eye treatment with artificial tears. Schirmer's, tear break-up time (TBUT) and osmolarity tests were measured before and after eight weeks of treatment.

RESULTS

The mean age of participants was 36.8 ± 8.56 years in the treatment group (n: 50) and 34.8 ± 10.13 year in the control group (n: 50). After eight weeks of treatment the mean differences in Schirmer's, TBUT and tear osmolarity were 2.38 ± 1.55 mm, 3.95 ± 1.48 s and -16.9 ± 6.28 mOsm/L, respectively in the treatment group, and 0.7 ± 0.86 mm, 0.92 ± 1.57s and -3.34 ± 2.0 mOsm/L respectively in the control group (p < 0.001 for all parameters). The treatment group demonstrated a more significant improvement than the control group in Schirmer<apos;>s, TBUT and osmolarity values (p < 0.001).

CONCLUSION

Vitamin D supplementation as an adjuvant to routine dry eye treatment improves ocular surface hemostasis parameters, results in better tear stability and a more improved tear osmolarity in patients with vitamin D deficiency.

Vitamin D Deficiency, Osteoporosis and Effect on Autoimmune Diseases and Hematopoiesis: A Review

Vitamin D (VD) is essential for bone homeostasis, but it is also involved in pleiotropic effects on various organs and tissues. In adults, VD deficiency can cause or exacerbate osteoporosis and induce osteomalacia. However, every tissue and cell in the body has a VD receptor, including the brain, heart, stomach, pancreas, skin, gonads, and immune cells, and a deficiency may modify the function of these organs. Thus, the wide-ranging actions of VD help to explain why a reduction in VD amount has been correlated with numerous chronic diseases. In fact, VD deficiency increases the risk of osteoporosis and several other diseases and complications characterized by impaired bone metabolisms, such as autoimmune diseases, inflammatory bowel diseases, allergy, endocrinological diseases, hematological malignancies, and bone marrow transplantation. This review aims to investigate the link between VD deficiency, osteoporosis, and its concomitant diseases. Further epidemiological and mechanistic studies are necessary in order to ascertain the real role of hypovitaminosis in causing the reported diseases; however, adequate vitamin supplementation and restoration of metabolic normality could be useful for better management of these pathologies.

Prevalence of Tear Film Hyperosmolarity in 1150 patients presenting for refractive surgery assessment

PURPOSE

To present an analysis of tear film hyperosmolarity in a large, consecutive population and evaluate the correlation of ocular and systemic conditions with tear film osmolarity.

SETTING

Private practice Sydney, Australia.

DESIGN

Single-centre, retrospective, consecutive cohort.

METHOD

1404 patients (n=1357 standard, n=47 post-refractive) undergoing screening for laser refractive surgery from October 2017 to October 2020 were reviewed. Routine examination included tear film osmolarity (TFO) and Ocular Surface Disease Index questionnaire). TFO was conducted prior to further tests and patients refrained from topical eye drops minimum two hours before the appointment.

RESULTS

Mean highest TFO in the standard population was 299.12±11.94mOsm/L with 82.3% of eyes <308mOsm/L indicating normal tear film homeostasis. The mean inter-eye TFO difference was 8.17±8.60mOsm/L with 65.2% of eyes <=8mOsm/L. Mean highest TFO in the post-refractive subgroup was 299.72±11.00mOsm/L with a mean inter-eye difference of 9.02±6.92mOsm/L. Post-refractive surgery patients indicated higher mean OSDI values of 15.28±14.46 compared to the remainder of the population 9.69±10.56 (p=0.012). Significant correlation was demonstrated between TFO scores and OSDI normal classification in the standard population only (p=0.005, r=0.077). The use of contact lens correlated inversely with TFO and OSDI scores (p=0.000, r=-0.136 and p=0.000, r=-0.152 respectively).

CONCLUSION

Our study represents the largest available cohort of TFO scores in a standard population presenting for refractive surgery. We found that although the majority of patients can be expected to fall within normal ranges, a reasonable percentage will be diagnosed with tear hyperosmolarity and therefore at risk of dry eye disease.

Ocular Findings Among Patients With Vitamin D Deficiency

Objective The aim of this study was to evaluate the ocular findings in patients with low vitamin D levels. Methods All patients who attended the Internal Medicine Clinic between March 2018 and February 2020 with vitamin low D levels but had been untreated for the same were included in our study. The exclusion criteria were as follows:history of intraocular surgery, trauma, steroid use, secondary glaucoma, and history of rheumatologic diseases. The patients were classified into three groups: group 1 had severe deficiency with vitamin D levels below 10 µg/L; group 2 had vitamin deficiency with levels of 10-20 µg/L; and group 3 had vitamin D insufficiency with levels of 20-30 µg/L. A comparison among groups was performed in terms of intraocular pressure (IOP), retinal nerve fiber layer (RNFL) thickness, central macular thickness (CMT), dry eyes, cataract, glaucoma, macular degeneration, and refractive error. The evaluation of statistical data was performed with the SPSS Statistics software version 22 (IBM, Armonk, NY). Results There were a total of 98 patients and 196 eyes, who were classified into three groups. There were 41 patients in group 1, 45 in group 2, and 12 in group 3. Groups were similar in terms of age (p=0.25) and gender (p=0.46). The average age among the cohort was 51 ± 13.08 years; 65 (66.3%) of the patients were female and 33 (33.7%) were male. There was no statistically significant difference in terms of IOP (p=0.55), dry eyes (p=0.35), cataract (p=0.22), glaucoma (p=0.50), macular degeneration (p=0.64), and refractive error (p=0.46) among the groups. There was a statistically significant difference in CMT between group 1 and other groups (p=0.002 and p=0.002, respectively). Also, there was a statistically significant difference in RNFL thickness between group 1 and group 2 (p=0.01). When compared in terms of quadrants, a significant difference was found only with regard to the nasal quadrant. Conclusion Based on our findings, lower levels of 25-hydroxyvitamin D might be related to thinning in CMT. Regarding RNFL thickness, while there was a significant difference between groups 1 and 2, there was no difference between groups 1 and 3, and hence the association between lower levels of 25-hydroxyvitamin D and thinning in RNFL thickness could not be clearly established. Hence, we have assumed that lower levels of 25-hydroxyvitamin D might cause thinning in the macula and nasal quadrant of RNFL, and vitamin D deficiency might affect the nasal quadrant of RNFL primarily. Further long-term studies with a larger number of patients might clarify the relationship between vitamin D deficiency and the thinning in CMT, RNFL quadrants, and RNFL thickness.

Vitamin D deficiency is associated with dry eye syndrome: a systematic review and meta-analysis

A systematic review and meta-analysis was conducted to determine the association between the serum vitamin D level and dry eye. A systematic literature search was performed using the PubMed, Embase, Web of Science and Cochrane Library databases to identify clinical studies evaluating the association between vitamin D levels and dry eye. The random-effect model was used to combine the results. Possible sources of heterogeneity across studies were determined by meta-regression and sensitivity analysis. Overall, 10 studies (n = 18 919) were included. Patients with dry eye had a mean serum vitamin D level that was lower than that in healthy controls by 3.99 ng/ml (95% CI -6.57, -1.40; p = 0.002). The mean Ocular Surface Disease Index score was higher (mean difference 10.70, 95% CI 1.55-19.86; p = 0.02) and Schirmer's test without anaesthesia result was lower (mean difference 6.38 mm/5 min, 95% CI -10.48, -2.28; p = 0.002) in patients with vitamin D deficiency than in controls. Tear break-up time was comparable in the vitamin D deficiency and control groups (p = 0.15). Sensitivity analyses indicated that the results obtained were robust. This meta-analysis suggested that vitamin D deficiency is associated with worse subjective symptoms and less tear production in patients with dry eye. Vitamin D deficiency may be a risk factor for dry eye syndrome. Prospective cohort and intervention studies are warranted to determine if vitamin D has a protective role in the development of dry eye.

Genistein-Calcitriol Mitigates Hyperosmotic Stress-Induced TonEBP, CFTR Dysfunction, VDR Degradation and Inflammation in Dry Eye Disease

Dry eye disease (DED) signs and symptoms are causally associated with increased ocular surface (OS) inflammation. Modulation of key regulators of aberrant OS inflammation is of interest for clinical management. We investigated the status and the potential to harness key endogenous protective factors, such as cystic fibrosis transmembrane conductance regulator (CFTR) and vitamin D receptor (VDR) in hyperosmotic stress‐associated inflammation in patients with DED and in vitro. Conjunctival impression cytology samples from control subjects (n = 11) and patients with DED (n = 15) were used to determine the status of hyperosmotic stress (TonEBP/NFAT5), inflammation (IL‐6, IL‐8, IL‐17A/F, TNFα, MMP9, and MCP1), VDR, and intracellular chloride ion (GLRX5) by quantitative polymerase chain reaction and/or immunofluorescence. Human corneal epithelial cells (HCECs) were used to study the effect of CFTR activator (genistein) and vitamin D (calcitriol) in hyperosmotic stress (HOs)‐induced response in vitro. Western blotting was used to determine the expression of these proteins, along with p‐p38. Significantly, higher expression of inflammatory factors, TonEBP, GLRX5, and reduced VDR were observed in patients with DED and in HOs‐induced HCECs in vitro. Expression of TonEBP positively correlated with expression of inflammatory genes in DED. Increased TonEBP and GLRX5 provides confirmation of osmotic stress and chloride ion imbalance in OS epithelium in DED. These along with reduced VDR suggests dysregulated OS homeostasis in DED. Combination of genistein and calcitriol reduced HOs‐induced TonEBP, inflammatory gene expression, and p‐p38, and abated VDR degradation in HCECs. Henceforth, this combination should be further explored for its relevance in the management of DED.

Serum 25-Hydroxy Vitamin D, Vitamin B12, and Folic Acid Levels in Progressive and Nonprogressive Keratoconus

PURPOSE

To evaluate the serum 25-hydroxy vitamin D, vitamin B12, and folic acid (FA) levels in progressive and nonprogressive patients with keratoconus (KCN).

METHODS

Fifty-five patients with KCN (28 progressive and 27 nonprogressive) who were followed up for at least 12 months were recruited and separated into 2 groups according to corneal topographic progression criteria. Age- and sex-matched 30 healthy individuals formed the control group. Serum vitamin D, B12, FA, and Ca levels were compared among control, nonprogressive, and progressive groups. The effect of gender, age, vitamin D, B12, and FA parameters on KCN progression was investigated.

RESULTS

Serum vitamin D levels were 12.77 ± 5.52, 11.78 ± 4.32, and 17.40 ± 5.12 ng/mL in nonprogressive, progressive, and control groups, respectively. The serum vitamin D levels in KCN groups (nonprogressive and progressive) were significantly lower than the control group (P = 0.002 and P < 0.001, respectively). There was no significant difference between all groups in serum vitamin B12, FA, and Ca levels (P > 0.05). Decreased vitamin D levels significantly increased nonprogressive KCN probability 1.23 times and progressive KCN probability 1.29 times more than the control group (P = 0.002, 95% confidence interval, 0.708-0.925; P < 0.001, 95% confidence interval, 0.668-0.888, respectively).

CONCLUSIONS

Serum vitamin D levels were significantly decreased in both KCN groups. However, serum vitamin B12, FA, and Ca levels were similar in all groups. Serum vitamin D evaluation of patients with KCN at onset and follow-up examinations may help to predict the course of the disease.

A prospective study to assess the role of vitamin D individually and in combination with cyclosporine in the treatment of dry eye in patients with deficient serum 25(OH)D levels

Purpose:

To study the efficiency of vitamin D3 (buccal spray) alone and combination of vitamin D3 with cyclosporine in the treatment of dry eye disease (DED) in patients with deficient serum 25(OH)D levels.

Methods:

Around 90 patients with DED with deficient serum 25(OH)D levels were included and randomized into three groups and were given treatment for dry eye (Group A- 0.5% carboxymethylcellulose (CMC), Group B- 0.5% CMC + 2000 IU vitamin D through buccal spray, Group C- 0.5% CMC + 2000 IU vitamin D through buccal spray + 0.05% cyclosporine). The patients were followed at day-15, day-30, and day-90 for improvement in tear breakup time (TBUT) and Schirmer’s, and ocular surface disease index (OSDI) score. Improvement in serum vitamin D level was assessed at day-90. One way ANOVA test, paired t-test, and Chi-square test were used for analysis.

Results:

Group B and Group C had significantly higher in Schirmer’s test-I values as compared to Group A (P = 0.001, P < 0.001, P < 0.001 at day-15, day-30, and day-90, respectively). Significantly higher values of TBUT and mean serum vitamin D levels were obtained in Group B and Group C as compared to Group A at day-90 (P < 0.05). OSDI scores of patients significantly decreased in all three groups at all follow-up visits (P < 0.05). Overall, Group C and Group B were found statistically better than Group A. Group C showed better results than Group B but they were nonsignificant.

Conclusion:

Vitamin D supplementation leads to earlier and significant improvement in TBUT, Schirmer’s, and OSDI score in patients with vitamin D deficient DED.

Conjunctival impression cytology and tear-film changes in cases with vitamin D deficiency

PURPOSE

To evaluate conjunctival surface cells and tear-film functions in cases with vitamin D deficiency.

METHODS

Thirty-six patients with serum vitamin D deficiency and 27 control subjects with normal serum vitamin D levels were included in this prospective study. The tear break-up time (TBUT), Schirmer II test, and conjunctival impression cytology tests were performed to all participants.

RESULTS

The mean serum vitamin D levels were 10.5 ± 5.0 µl in the study group and 33.9 ± 11.7 µl in the control group (p < 0.001). The median TBUT scores were 11 s and 17 s and the median Schirmer II values were 7.5 mm and 12 mm in the study and the control groups, respectively (p = 0.003, p = 0.049). According to the Nelson staging system, 69.4% of the patients in the study group had grade 2 or 3 impression cytology, whereas 18.5% of the participants in the control group had grade 2 or 3 impression cytology (p < 0.001).

CONCLUSION

Our study results showed that vitamin D deficiency may lead to dry eye causing conjunctival squamous metaplasia and loss of goblet cells on the ocular surface.

Serum 25-Hydroxyvitamin D, Selenium, Zinc and Copper in Patients with Keratoconus

PURPOSE

To assess the possible association between keratoconus (KC) and serum levels of 25-hydroxyvitamin D (25OHD), Selenium (Se), Zinc (Zn), and Copper (Cu) and to compare it with age-matched healthy subjects.

METHODS

One hundred patients with KC and 100 normal subjects were included. The two groups were compared for serum 25OHD and serum levels of three trace elements: Se, Zn, and Cu. These factors were also compared between groups with different KC stages.

RESULTS

Serum levels of vitamin D, Zn, Cu, and Se were significantly different between the KC and normal groups (P = 0.006, P = 0.015, P = 0.004, and P = 0.038, respectively). Although a lower level of 25OHD was found in severe stages of KC, it was not significantly different among different KC groups (P = 0.441). KC stage groups were not significantly different for mean serum Zn, Cu, and Se (P = 0.130, P = 0.98, P = 0.113, respectively). Although the Cu/Zn ratio was higher in cases than in controls, there was no significant difference between the two groups and between KC stages (P = 0.168, P = 0.143, respectively).

CONCLUSION

Lower serum 25OHD, Cu, Zn, and Se were found in the KC group compared to the control group. The results of this study suggest that a lower antioxidative activity may be involved in the possible etiology of KC.

Dysregulated Tear Fluid Nociception-Associated Factors, Corneal Dendritic Cell Density, and Vitamin D Levels in Evaporative Dry Eye

Purpose

The purpose of this study was to study the status and association among tear-soluble factors, corneal dendritic cell density, vitamin D, and signs and symptoms in dry eye disease (DED).

Methods

A total of 33 control subjects and 47 evaporative dry eye patients were included in the study. DED diagnosis and classification was based on the 2017 Report of the Tear Film & Ocular Surface Society International Dry Eye Workshop (TFOS DEWS II). DED workup, including tear film break-up time (TBUT), Schirmer's test I (STI), corneal and conjunctival staining, ocular surface disease index (OSDI) scoring, and in vivo confocal microscopy (to assess corneal dendritic cell density [cDCD] and subbasal nerve plexus [SBNP] features) was performed in the study subjects. Tear fluid using Schirmer's strip and serum were collected from the subjects. Multiplex ELISA or single analyte ELISA was performed to measure 34 tear-soluble factors levels including vitamin D.

Results

Significantly higher OSDI discomfort score, lower TBUT, and lower STI were observed in DED patients. cDCD was significantly higher in DED patients. No significant difference was observed in SBNP features. Tear fluid IL-1β, IL-17A, MMP9, MMP10, MMP9/TIMP ratio, and VEGF-B were significantly higher in DED patients. Significantly lower tear fluid IL-2, IP-10, NPY, VEGF-A, and vitamin D was observed in DED patients. These dysregulated tear factors showed significant associations with DED signs and symptoms.

Conclusions

Altered tear fluid soluble factors with potential to modulate nociception exhibited a distinct association with ocular surface discomfort status, TBUT, STI, and cDCD. This implies a functional relationship between the various tear-soluble factors and dry eye pathogenesis, indicating new molecular targets for designing targeted therapies.

Vitamin D Enhances the Efficacy of Topical Artificial Tears in Patients With Dry Eye Disease

PURPOSE

To investigate the efficacy of topical carbomer-based lipid-containing artificial tears (CLAT) and hyaluronate (HU) in patients with dry eye disease (DED) based on serum 25-hydroxyvitamin D (25HD) levels and cholecalciferol (vitamin D) supplementation.

METHODS

A total of 116 patients with DED from June 2015 to June 2016 were included. The participants were divided into the vitamin D deficiency (VDD) group and the non-VDD group according to their serum 25HD levels. The patients determined the ways of cholecalciferol supplementation. Ocular Surface Disease Index (OSDI) score, visual analog pain scale score, lid hyperemia, tear breakup time (TBUT), corneal fluorescein staining score, and Schirmer test were compared between baseline and 2 weeks posttreatment after topical applications and between before and after cholecalciferol supplementation.

RESULTS

The OSDI and visual analog pain scale scores of both VDD and non-VDD groups decreased after application of topical CLAT and HU compared with baseline values (P < 0.05 for all, paired t test). TBUT, corneal fluorescein staining score, and lid hyperemia in the VDD group remained unaffected by topical CLAT and HU, whereas those in the non-VDD group were improved (3.2 ± 1.7 vs. 4.1 ± 2.2, 0.5 ± 0.7 vs. 0.4 ± 0.6, and 2.2 ± 0.8 vs. 1.9 ± 0.7 in the non-VDD group, P = 0.001, 0.030, and 0.012, respectively). OSDI score, TBUT, and lid margin hyperemia were improved in the intramuscular group after cholecalciferol supplementation compared with pretreatment (33.2 ± 23.2 vs. 28.5 ± 21.9, 3.5 ± 1.9 vs. 6.0 ± 2.5, and 2.2 ± 0.7 vs. 1.2 ± 0.8, P < 0.05, Wilcoxon rank test).

CONCLUSIONS

The effect of topical CLAT and HU was dependent on serum 25HD levels. Cholecalciferol supplementation enhanced the efficacy of topical treatment and may be a useful adjuvant therapy for patients with DED refractory to topical lubricants.