Clinical outcomes of ocular surface in patients treated with vitamin D oral replacement

Low Expression of Vitamin D Receptor in Patients With Dry Eye Disease

PURPOSE

This study aimed to compare the expression of vitamin D receptor (VDR) on the ocular surface of patients with dry eye disease (DED) and controls without ophthalmological pathologies.

METHODS

Patients with DED without previous treatment were studied and compared with healthy subjects. Ocular Surface Disease Index assessement and ocular surface cytology were performed in all patients. The immunohistochemical expression of VDR was evaluated using fully automated immunohistochemistry. The evaluation involved multiplying the percentage of nuclear-labeled cells (0-100) by their intensity (0-3), resulting in a score ranging from 0 to 300 (VDR H-score). Squamous metaplasia was morphologically evaluated using liquid-phase cytology with Papanicolaou/periodic acid-Schiff staining using Nelson's grade (scale 0-3, higher grade to higher metaplastic change).

RESULTS

Eighteen patients with DED without previous treatment and 10 healthy subjects were studied. Squamous metaplasia was observed in 74% of patients with DED, in contrast to 0% in the control group. In patients with DED, there was a lower expression of VDR than in the control group (VDR H-score: 11.2 ± 13.9 vs. 80.9 ± 56; P = 0.0001). Furthermore, an inverse correlation was observed between Nelson grade and VDR H-score ( P = 0.0001, rs = -0.71). No correlation was observed between Ocular Surface Disease Index and VDR H-score.

CONCLUSIONS

This is the first study to evaluate the VDR in patients with DED. These patients presented with a lower expression of VDR than healthy subjects. No correlation was found with more severe symptoms. Patients with DED also had a higher frequency of squamous metaplasia.

Safety and Efficacy of Topical Vitamin D in the Management of Dry Eye Disease Associated With Meibomian Gland Dysfunction: A Placebo-Controlled Double-Blind Randomized Controlled Trial

PURPOSE

The aim of this study was to investigate the safety and efficacy of topical vitamin D in the management of dry eye disease associated with meibomian gland dysfunction (MGD).

METHODS

In this randomized controlled trial, patients with symptomatic MGD were divided into 2 groups to receive topical vitamin D drops or placebo in their randomized eyes. The exclusion criteria consisted of patients with vitamin D deficiency, previous ocular surgery, and patients with ocular diseases affecting the tear film. Patients and researchers were masked to the study groups. The outcomes included the score of Dry Eye Questionnaire (DEQ) 5 and Ocular Surface Disease Index (OSDI), corneal and conjunctival staining score, tear breakup time (TBUT), Schirmer, and MG expressibility score evaluated at baseline and weeks 4 and 8.

RESULTS

Twenty-eight eyes of 28 patients were recruited in each group. In addition to the improvement of subjective parameters in both groups, there was a statistically significantly greater improvement in the vitamin D group compared with control for average scores of OSDI (13.38 ± 7.32 vs. 27.94 ± 7.49) and DEQ5 (9.67 ± 1.86 vs. 14.14 ± 2.45) at week 8 (Ps <0.001). In addition, a significant improvement in TBUT and Schirmer test was observed in both groups in weeks 4 and 8 ( P value <0.05). There was a significant difference between the treatment and control groups after 8 weeks for OSDI, DEQ5, Schirmer, TBUT, corneal fluorescein staining, and MG expressibility score ( P value <0.05).

CONCLUSIONS

The preliminary results of this randomized controlled trial suggested that use of topical vitamin D drops with a lipid vehicle could be safe and might significantly improve the symptoms and signs of dry eye associated with MGD.

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.

Histopathological changes in extraocular muscles of rabbits following injection of Bupivacaine 5mg/ml versus 7.5mg/ml

PURPOSE

To compare the histopathological effects of injecting 2 concentrations of Bupivacaine (5mg/ml and 7.5mg/ml) in the superior rectus muscle of rabbits, and to compare these to conventional extraocular muscle surgery in previous studies.

METHODS

Eighteen albino rabbits' eyes were used. The superior rectus muscles were injected with Bupivacaine 5mg/ml (Group B5, 10 eyes) or 7.5mg/ml (Group B7, 8 eyes). The rabbits were sacrificed and eyes enucleated 6 weeks later for histopathological evaluation. Results were compared to the average of those obtained, by 3 previous studies, after conventional superior rectus resection in rabbits.

RESULTS

Foreign body reaction was absent in all specimens. Conjunctival and scleral inflammation, perimuscular adhesions, intramuscular fibrosis, conjunctival and scleral oedema and muscle atrophy were higher in group B7, while conjunctival hyperaemia and muscle hypertrophy were higher in group B5 (p > .05). On comparison to conventional surgery, conjunctival inflammation and hyperaemia, foreign body reaction, and adhesions were less after bupivacaine injection (p >.05 for all except for intensity of conjunctival inflammation in B5 versus conventional surgery). Scleral inflammation was more frequent after bupivacaine injection (p <.05). Muscle fibrosis was more frequent in group B7 and conventional surgery than in group B5 (p >.05).

CONCLUSIONS

Both Bupivacaine concentrations effectively produced the desired muscle hypertrophy and fibrosis, so the lower concentration may be used for muscle strengthening to correct strabismus. Bupivacaine injection, although produced no foreign body reaction, did not significantly lower the development of undesired postoperative adhesions and caused more scleral inflammation.

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.

Anti-Inflammatory and Anti-Oxidative Synergistic Effect of Vitamin D and Nutritional Complex on Retinal Pigment Epithelial and Endothelial Cell Lines against Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a multifactorial disease of the retina featured by dysfunction of retinal pigmented epithelial (RPE) and loss of photoreceptor cells under oxidative stress and inflammatory conditions. Vitamin D and antioxidants have beneficial effects against retinal degenerative diseases, such as AMD. We investigated the impact of associating vitamin D (ND) with a nutritional antioxidant complex (Nutrof Total^®; N) on oxidative stress and inflammation-like induced conditions by H₂O₂ and LPS, respectively, in human retinal epithelial (ARPE-19) and human retinal endothelial (HREC) cells. Application of either N or ND treatments to H₂O₂-induced media in ARPE-19 cells counteracted late apoptosis, attenuated oxidative DNA damage, and increased cell proliferation. Significant reduction in the expression levels of MCP1, IL-8, and IL6 cytokines was observed following application of either N or ND treatments under LPS-induced conditions in ARPE-19 cells and in MCP-1 and IL12p70 cytokine levels in HREC cells. ND and not N revealed significant downregulation of IFNγ in ARPE-19 cells, and of IL-6 and IL-18 in HREC cells. In conclusion, adding vitamin D to Nutrof Total^® protects in a synergistic way against oxidative and inflammatory stress-induced conditions in retinal epithelial and endothelial cells.

Relation of Dietary Fatty Acids and Vitamin D to the Prevalence of Meibomian Gland Dysfunction in Japanese Adults: The Hirado-Takushima Study

Intervention studies have shown that n-3 polyunsaturated fatty acid (PUFA) supplementation is effective for the treatment of meibomian gland dysfunction (MGD). Ointment containing an analog of vitamin D has also been found to improve symptoms and signs of MGD. We have now evaluated the relation of MGD prevalence to dietary intake of fatty acids (FAs) and vitamin D among a Japanese population. Subjects comprised 300 adults aged 20 to 92 years residing on Takushima Island. MGD was diagnosed on the basis of subjective symptoms, lid margin abnormalities, and meibomian gland obstruction. Dietary FA and vitamin D intake was estimated with a brief-type self-administered diet history questionnaire. MGD prevalence was 35.3%. Multivariate adjusted odds ratios (95% confidence intervals) between extreme quintiles of intake for MGD prevalence were 0.40 (0.16–0.97) for total fat, 0.40 (0.17–0.97) for saturated FAs, 0.40 (0.17–0.97) for oleic acid, 0.52 (0.23–1.18) for n-3 PUFAs, 0.63 (0.27–1.49) for n-6 PUFAs, 1.32 (0.59–2.95) for the n-6/n-3 PUFA ratio, and 0.38 (0.17–0.87) for vitamin D. Total fat, saturated FA, oleic acid, and vitamin D intake may thus be negatively associated with MGD prevalence in the Japanese.