Vitamin D status and early age-related macular degeneration in postmenopausal women

A narrative review on dietary components and patterns and age-related macular degeneration

Age-related macular degeneration (AMD) is one of the most prevalent eye diseases among the ageing population worldwide. It is a leading cause of blindness in individuals over 55, particularly in industrialised Western countries. The prevalence of AMD increases with age, and genetic factors and environmental influences are believed to contribute to its development. Among the environmental factors, diet plays a significant role in AMD. This review explores the association between dietary components, dietary patterns and AMD. Various nutrients, non-nutrient substances and dietary models that have the potential to counteract oxidative stress and inflammation, which are underlying mechanisms of AMD, are discussed. Consuming fruits, vegetables, fish and seafood, whole grains, olive oil, nuts and low-glycaemic-index foods has been highlighted as beneficial for reducing the risk of AMD. Adhering to the Mediterranean diet, which encompasses these elements, can be recommended as a dietary pattern for AMD. Furthermore, the modulation of the gut microbiota through dietary interventions and probiotics has shown promise in managing AMD.

Lipofuscin, Its Origin, Properties, and Contribution to Retinal Fluorescence as a Potential Biomarker of Oxidative Damage to the Retina

Lipofuscin accumulates with age as intracellular fluorescent granules originating from incomplete lysosomal digestion of phagocytosed and autophagocytosed material. The purpose of this review is to provide an update on the current understanding of the role of oxidative stress and/or lysosomal dysfunction in lipofuscin accumulation and its consequences, particularly for retinal pigment epithelium (RPE). Next, the fluorescence of lipofuscin, spectral changes induced by oxidation, and its contribution to retinal fluorescence are discussed. This is followed by reviewing recent developments in fluorescence imaging of the retina and the current evidence on the prognostic value of retinal fluorescence for the progression of age-related macular degeneration (AMD), the major blinding disease affecting elderly people in developed countries. The evidence of lipofuscin oxidation in vivo and the evidence of increased oxidative damage in AMD retina ex vivo lead to the conclusion that imaging of spectral characteristics of lipofuscin fluorescence may serve as a useful biomarker of oxidative damage, which can be helpful in assessing the efficacy of potential antioxidant therapies in retinal degenerations associated with accumulation of lipofuscin and increased oxidative stress. Finally, amendments to currently used fluorescence imaging instruments are suggested to be more sensitive and specific for imaging spectral characteristics of lipofuscin fluorescence.

[Nutrition and age-related macular degeneration]

Age-related macular degeneration (AMD) is the leading cause of vision loss in France and in other industrialized countries. AMD affects around 20 % of the population over the age of 80 years. This complex and multifactorial disease involves both genetic susceptibility and environmental factors. Smoking and nutrition are well-known modifiable risk factors for AMD. Numerous studies provide convincing arguments in favor of micronutrients to encourage dietary advice and the prescription of nutritional supplements containing antioxidant vitamins, lutein and omega-3 fatty acids. Attention to modifiable risk factors is of utmost importance to reduce progression to advanced AMD and associated medical and societal burdens.

Association Between Vitamin Deficiencies and Ophthalmological Conditions

Vitamin deficiencies can have adverse effects on health, including on the visual system. The ocular manifestations of a vitamin deficiency are related to the underlying biochemical function of the particular nutrient. While vitamin deficiencies are not common in developed counties, they are still prevalent in parts of the developing world and in specific, vulnerable populations. Vitamin deficiencies can cause or contribute to many ophthalmological conditions and eye diseases may even be the first presenting finding of a vitamin deficiency. As such, it is important for ophthalmologists to be aware of the ocular manifestations of vitamin deficiencies, especially given that the complications can be severe and effectively treated if identified early. This review summarizes the literature on the main vitamins known to have characteristic ocular manifestations: vitamins A, B1, B2, B9, B12, C, D, E and K. The function, epidemiology, manifestations, workup, and management of each vitamin is discussed in detail.

Serum 25-Hydroxyvitamin D Is Differentially Associated with Early and Late Age-Related Macular Degeneration in the United States Population

BACKGROUND

Age-related macular degeneration (AMD) has been the leading cause of irreversible blindness in industrialized countries. Emerging data suggest that serum vitamin D levels may be associated with AMD but show mixed results. National-level population data on the relationship between vitamin D and AMD severities are still lacking.

METHODS

We used data from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2008. Retinal photographs were taken and graded for AMD stage. The odds ratio (OR) of AMD and its subtype was calculated after adjusting for confounding factors. Restricted cubic spline (RCS) analyses were used to explore potential non-linear relations.

RESULTS

A total of 5041 participants with a mean age of 59.6 years were included. After adjusting for covariates, participants with higher level of serum 25-hydroxyvitamin D [25(OH)D] had significantly greater odds of early AMD (OR, 1.65; 95% CI, 1.08-2.51) and decreased risk of late AMD (OR, 0.29; 95% CI, 0.09-0.88). When stratified by age, a positive association between the level of serum 25(OH)D and early AMD was present in the <60 years group (OR, 2.79; 95% CI, 1.08-7.29), whereas a negative relation between the level of serum 25(OH)D and late AMD was detected in the ≥60 years group (OR, 0.24; 95% CI, 0.08-0.76).

CONCLUSIONS

A higher level of serum 25(OH)D was related to increased risk of early AMD in those <60 years and decreased risk of late AMD in those ≥60 years.

The Relationship between Dietary Calcium and Age-Related Macular Degeneration

BACKGROUND

Mineral element supplements are widely used in the older adult population. However, little is known of their impact on the progression of age-related macular degeneration (ARMD). The aim of this study was to examine the association between dietary micronutrients and ARMD in older adults.

METHODS

We enrolled 5227 participants from the National Health and Nutrition Examination Survey (NHANES 2005-2008) in this cross-sectional study. ARMD was evaluated using an ophthalmic digital imaging system and digital camera. Mineral element consumption was collected using a 24-hour dietary recall. The association between mineral element use and the presence of ARMD was determined by multivariable logistic regression.

RESULTS

After adjusting for relevant variables, dietary calcium was negatively associated with ARMD (OR: 680, 95%CI: 0.482-0.960). In contrast to dietary form, serum concentration of calcium was not associated with ARMD. Moreover, increased dietary calcium was associated with reduced ARMD (OR: 0.684, 95%CI: 0.468-1.000).

CONCLUSION

A lower consumption of dietary calcium was significantly associated with a higher risk of ARMD. Further longitudinal studies are necessary to explore these findings.

Evaluation of 25-Hydroxyvitamin D levels in patients with dermatochalasis

PURPOSE

To compare serum 25-hydroxyvitamin D (25(OH)D) levels of patients with dermatochalasis who underwent upper lid blepharoplasty and healthy controls.

METHODS

This retrospective comparative study included dermatochalasis patients who underwent upper lid blepharoplasty and age-and sex-matched controls from January 2019 to January 2021. The data, including comprehensive ophthalmological examination, internal medicine outpatient examination, and laboratory results of the dermatochalasis patients and healthy controls, were collected from the electronic patient records. Serum 25(OH)D, creatinine, calcium (Ca), phosphate (P), triglyceride (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) levels were evaluated and compared between the dermatochalasis patients and healthy controls.

RESULT

Of our participants, consisting of 46 patients with dermatochalasis and 52 healthy controls, 54 (55.10%) were female and 44 (44.90%) were male. A statistically significant difference was observed in vitamin D levels between the healthy and dermatochalasis groups (p ≤ 0.001). The percentage of individuals with vitamin D deficiency (< 20 ng/mL) was significantly higher in the dermatochalasis group (p = 0.001). In addition, the percentage of individuals with severe vitamin D deficiency (< 10 ng/mL) was again significantly higher in the dermatochalasis group (p = 0.001). The risk of dermatochalasis incidence was found to increase in cases of low vitamin D (OR = 1.210; p = 0.017).

CONCLUSION

Low serum 25(OH)D levels may play a role in the etiopathogenesis of dermatochalasis. Future research should include longitudinal studies and prospective clinical studies to investigate the mechanism responsible for the low vitamin D observed in dermatochalasis patients.

Association of Vitamin D deficiency with primary glaucoma among Saudi population - A pilot study

PURPOSE

Glaucoma is a complex multifactorial disorder that is influenced by various systemic conditions. Several studies investigated the association between systemic factors such as Vitamin D deficiency for glaucoma development and reported contradicted findings. The aim of this study was to assess Vitamin D levels in glaucomatous Saudi subjects and its association with cup/disc ratio in primary open- and closed-angle glaucoma.

METHODS

This was a pilot study that included subjects aged 41-78 years from both genders recruited from a tertiary hospital, Riyadh city, Kingdom of Saudi Arabia. Subjects were divided into three groups: Group 1: subjects with primary open-angle glaucoma (POAG), Group 2: subjects with primary angle-closure glaucoma (PACG), and Group 3: control subjects. All participants underwent detailed ophthalmic examinations including visual acuity, intraocular pressure measurement (IOP), gonioscopy, and fundus examinations. In addition, blood samples were collected from glaucoma patients and controls to measure the serum 25-hydroxyvitamin D levels.

RESULTS

A total of 75 subjects were included in this study. Measurement of IOP was within the range of 9-27 for all subjects. Mean serum 25-hydroxyvitamin D levels were 72.58 ± 31.79, 69.20 ± 24.24, and 67.14 ± 29.02 in Groups 1, 2, and 3, respectively. There were insignificant differences in Vitamin D levels among the three groups (P > 0.05). Moreover, no significant correlation was noted between Vitamin D levels and cup/disc ratio in Groups 1 and 2.

CONCLUSION

No association was found between Vitamin D deficiency and both POAG and PACG among Saudi population despite low serum level of Vitamin D in glaucomatous and control subjects. This study suggested that Vitamin D level may not contribute in augmenting the severity and progression of glaucoma.

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.

Changes in optical coherence tomography angiography in patients with vitamin D deficiency

PURPOSE

25-hydroxyvitamin D [25(OH)D] sufficiency has critical biological importance for the human body. Although there are several studies on the association between serum 25(OH)D levels and macular structure, the data in this regard are limited. This study mainly aimed to investigate macular microvascular structure using optical coherence tomography angiography (OCTA) in 25(OH)D deficiency.

STUDY DESIGN

Prospective, single-center, clinical study.

METHODS

The study included 82 eyes of 82 patients with 25(OH)D deficiency (Group I) and 50 eyes of 50 healthy subjects (Group II). All participants underwent OCTA examinations. The foveal avascular zone (FAZ) and superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) measurements of the participants were statistically compared between the patients and healthy subjects.

RESULTS

The mean 25(OH)D levels measured from the venous blood samples of the participants were 7.61 ± 3.27 ng/mL in Group I and 25.39 ± 4.16 ng/mL in Group II, and the difference between these values was statistically significant (p < 0.0001). The FAZ measurement was significantly higher in Group I. The VDs of the SCP and DCP measurements were significantly higher in Group II. When the central macular thickness values of the participants were compared, Group II had a significantly higher value, but there was no significant difference in the central macular volume and retinal nerve fiber layer thickness analyses.

CONCLUSION

The results showed that the FAZ area was significantly higher and the VDs of SCP and DCP were significantly lower in the patients with 25(OH)D deficiency. We found that 25(OH)D deficiency affected macular microvascular architecture.

Ophthalmic artery angioplasty for age-related macular degeneration

BACKGROUND

There is considerable overlap of contributors to cardiovascular disease and the development of age-related macular degeneration (AMD). Compromised ocular microcirculation due to aging and vascular disease contribute to retinal dysfunction and vision loss. Decreased choroidal perfusion is evident in eyes with dry AMD and is thought to play a role in retinal pigment epithelial dysfunction, the rate of development of geographic atrophy, and the development of neovascularization. The aim of the study was to demonstrate that AMD is correlated with a compromised blood flow in the ocular pathway and show OA angioplasty as a potential treatment of late-stage AMD.

METHODS

Based on the potential for the ophthalmic artery (OA) to be an anatomical target for the treatment of AMD as outlined above, five patients were found to be eligible for compassionate use treatment, presenting clinically significant late-stage AMD with profound vision loss in one or both eyes, and are included in this retrospective study.

RESULTS

OA narrowing, or significant calcium burden at the ophthalmic segment of the internal carotid artery compromising the origin of the OA was confirmed in all cases. Subsequent OA cannulation was achieved in all patients with some difficulty. Subjective patient reports indicated that all patients perceived a benefit following the procedure; however, improved postoperative visual acuity did not confirm that perceived benefit for one of the patients.

CONCLUSIONS

Feasibility and safety of the OA angioplasty were demonstrated, and a benefit perceived in five patients with profound vision loss and a desire to achieve improved quality of life. A clinical trial with controlled schedule, imaging, and methodologies is needed to confirm these results.

Role of Optical Coherence Tomography Imaging in Predicting Progression of Age-Related Macular Disease: A Survey

In developed countries, age-related macular degeneration (AMD), a retinal disease, is the main cause of vision loss in the elderly. Optical Coherence Tomography (OCT) is currently the gold standard for assessing individuals for initial AMD diagnosis. In this paper, we look at how OCT imaging can be used to diagnose AMD. Our main aim is to examine and compare automated computer-aided diagnostic (CAD) systems for diagnosing and grading of AMD. We provide a brief summary, outlining the main aspects of performance assessment and providing a basis for current research in AMD diagnosis. As a result, the only viable alternative is to prevent AMD and stop both this devastating eye condition and unwanted visual impairment. On the other hand, the grading of AMD is very important in order to detect early AMD and prevent patients from reaching advanced AMD disease. In light of this, we explore the remaining issues with automated systems for AMD detection based on OCT imaging, as well as potential directions for diagnosis and monitoring systems based on OCT imaging and telemedicine applications.

Effects of Vitamin D3 and Meso-Zeaxanthin on Human Retinal Pigmented Epithelial Cells in Three Integrated in vitro Paradigms of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is a degenerative retinal disease and one of major causes of irreversible vision loss. AMD has been linked to several pathological factors, such as oxidative stress and inflammation. Moreover, Aβ (1-42) oligomers have been found in drusen, the extracellular deposits that accumulate beneath the retinal pigmented epithelium in AMD patients. Hereby, we investigated the hypothesis that treatment with 1,25(OH) ₂D₃ (vitamin D₃) and meso-zeaxathin, physiologically present in the eye, would counteract the toxic effects of three different insults on immortalized human retinal pigmented epithelial cells (ARPE-19). Specifically, ARPE-19 cells have been challenged with Aβ (1-42) oligomers, H₂O₂, LPS, and TNF-α, respectively. In the present study, we demonstrated that the combination of 1,25(OH)₂D₃ and meso-zeaxanthin significantly counteracted the cell damage induced by the three insults, at least in these in vitro integrated paradigms of AMD. These results suggest that combination of 1,25(OH)₂D₃ and meso-zeaxathin could be a useful approach to contrast pathological features of AMD, such as retinal inflammation and oxidative stress.

Reticular Pseudodrusen Characteristics and Associations in the Carotenoids in Age-Related Eye Disease Study 2 (CAREDS2), an Ancillary Study of the Women's Health Initiative

PURPOSE

To determine the prevalence and morphologic features of reticular pseudodrusen (RPD) and their association with participant demographics and age-related macular degeneration (AMD) status in the Carotenoids in Age-Related Eye Disease Study 2 (CAREDS2) sample, an ancillary study of the Women's Health Initiative Observational Study.

DESIGN

Cross-sectional, multicenter, natural history study.

PARTICIPANTS

Nine hundred and twenty-seven eyes from 466 postmenopausal women 69 to 101 years of age.

METHODS

Multimodal imaging, including spectral-domain (SD) OCT and infrared reflectance (IR), were used to identify RPD characteristics, including location (within or outside the 6-mm diameter circle centered at the macula), presence of peripapillary RPD, pattern of RPD, and RPD area. Age-related macular degeneration features from SD OCT, IR, and color photographs also were assessed and AMD severity was categorized.

MAIN OUTCOME MEASURES

Reticular pseudodrusen prevalence using SD OCT and IR imaging and AMD status.

RESULTS

Reticular pseudodrusen were present in 130 eyes (14% of eyes, 16% of participants), with increasing prevalence with age: 7% in those younger than 78 years, 14% in those 78 to 83 years of age, and 30% in those older than 83 years. Using clinical classification of AMD with color photography, RPD were seen in 2.4% of eyes with no AMD or aging changes, 11.5% in early AMD, 25.1% in intermediate AMD, and 51.1% in late AMD. Mean RPD area was 17.4 mm2 (standard deviation, 14.7 mm2). Ribbon morphologic RPD (53%) was more common than dot morphologic RPD (36%). Reticular pseudodrusen mostly were located both within and outside the 6-mm circle with primarily superior retinal distribution. Reticular pseudodrusen were visualized with corresponding color fundus photography in only 38 eyes (4% of total eyes). Participants with and without RPD had a visual acuity±standard error of 77.9 ± 1.4 letters and 81.3 ± 0.4 letters, respectively (P = 0.02).

CONCLUSIONS

The prevalence of RPD in CAREDS2 increased with age and was associated with AMD severity. Reticular pseudodrusen were detected in eyes without other features of AMD and could represent an earlier disease state. Multimodal imaging with SD OCT and IR has significantly greater sensitivity for visualizing RPD than color fundus photography.

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.

Untargeted metabolomics for uncovering plasma biological markers of wet age-related macular degeneration

Wet age-related macular degeneration (wAMD) causes central vision loss and represents a major health problem in elderly people. Here we have used untargeted metabolomics using UHPLC-MS to profile plasma from 127 patients with wAMD (67 choroidal neovascularization (CNV) and 60 polypoidal choroidal vasculopathy (PCV)) and 50 controls. A total of 545 biochemicals were detected. Among them, 17 metabolites presented difference between patients with wAMD and controls. Most of them were oxidized lipids (N=6, 35.29%). Comparing to controls, 28 and 18 differential metabolites were identified in patients with CNV and PCV, respectively. Two metabolites, hyodeoxycholic acid and L-tryptophanamide, were differently distributed between PCV and CNV. We first investigated the genetic association with metabolites in wet AMD (CFH rs800292 and HTRA1 rs10490924). We identified six differential metabolites between the GG and AA genotypes of CFH rs800292, five differential metabolites between the GG and AA genotypes of HTRA1 rs10490924, and four differential metabolites between the GG and GA genotypes of rs10490924. We selected four metabolites (cyclamic acid, hyodeoxycholic acid, L-tryptophanamide and O-phosphorylethanolamine) for in vitro experiments. Among them, cyclamic acid reduced the activity, inhibited the proliferation, increased the apoptosis and necrosis in human retinal pigment epithelial cells (HRPECs). L-tryptophanamide affected the proliferation, apoptosis and necrosis in HRPECs, and promoted the tube formation and migration in primary human retinal endothelial cells (HRECs). Hyodeoxycholic acid and O-phosphorylethanolamine inhibited the tube formation and migration in HRECs. The results suggested that differential metabolites have certain effects on wAMD pathogenesis-related HRPECs and HRECs.

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.

SERUM VITAMIN D LEVELS IN DIFFERENT MORPHOLOGIC FORMS OF AGE RELATED CATARACT

Purpose

Vitamin D insufficiency and age related cataract (ARC) are public health problems. We evaluated serum vitamin D levels in ARC patients.

Method

A prospective hospital-based cross-sectional study was designed to measure the vitamin D status of patients with ARC. Patients have grouped either presence of any type of posterior subcapsular cataract (PSC) (group 1) or ARC without the PSC component (Group 2). After full ophthalmologic consideration, patients over 40 years of age with no history of ocular trauma, multivitamin supplement ingestion, chronic renal failure, thyroidectomy, parathyroidectomy, skin cancer, and cigarette smoking were included in the study.

Results

Totally, 79 subjects of which 26 (32.9%) subjects in group 1 and 53 (67.1%) subjects in group 2 were included in the study. Group 1 had mean vitamin D levels of 17.31±13.30 ng/mL. Vitamin D levels in Group 2 were 13.34±7.87 ng/mL. Group 1 did not show vitamin D insufficiency (P = 0.31; one-sample t-test). However, Group 2 showed a statistically significantly lower vitamin D level compared to the insufficiency level of 20ng/mL (P= 0.00; one-sample t-test).

Conclusion

Vitamin D may have an important function in lens metabolism. Vitamin D deficiency and cataract development need further extensive researches.

Serum vitamin D and age-related macular degeneration: Systematic review and meta-analysis

Vitamin D may be implicated in the pathophysiology of several ocular diseases, but its role in age-related macular degeneration (AMD) remains uncertain. We sought to review systematically the existing evidence to evaluate the association between serum 25-hydroxyvitamin D 25(OH)D levels and AMD. A four-database search (PubMed, ISI Web of Science, Cochrane, and Scopus) was performed from inception to May 2020 using the MeSH terms: ("Macular Degeneration" OR "Age-related macular degeneration" OR "Retinal degeneration" OR "Macula lutea") AND ("Vitamin D" OR "Ergocalciferols" OR "Cholecalciferol" OR "25-Hydroxyvitamin D"). Random-effects meta-analyses were performed to compute 1) the standard mean difference in 25(OH)D concentration between AMD and non-AMD patients and 2) the AMD risk according to serum 25(OH)D levels. Eighteen observational studies enrolling 75,294 patients after a selection process among 375 original abstracts were selected. No significant differences were found, but there appears to exist a trend for late AMD among subjects with a serum 25(OH)D level below 50 nmol/L (odds ratio, 1.8; 95% confidence interval: 1.00-3.24, P = 0.05). There is no clear evidence of a definitive association between serum 25(OH)D and AMD risk, mainly due to heterogeneity in study procedures and lack of longitudinal designs.

Diet patterns and the incidence of age-related macular degeneration in the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss among the elderly.

OBJECTIVE

This study aimed to determine the association between dietary patterns and food groups (used to make them) with the 18-year incidence of AMD.

METHODS

ARIC (Atherosclerosis Risk in Communities) participants who showed change in AMD lesions between retinal photographs taken at visit 3 and visit 5 were graded side by side to determine incident AMD (any=144; early=117; late=27). A 66-line item food frequency questionnaire, administered at visit 1 and visit 3, was used to identify 29 food groups. Principal component analysis was used to derive dietary patterns from average food group servings. Logistic regression was used to estimate ORs and 95% CIs for incident AMD (any, early and late) by tertiles of dietary pattern scores, adjusted for age, race, education, total calories and smoking status. P-trend was estimated using continuous scores.

RESULTS

Western (unhealthy) and Prudent (healthy) dietary patterns were identified. No significant associations were observed between either dietary pattern and incident any or incident early AMD. However, a threefold higher incidence of late AMD was observed among participants with a Western pattern score above, as compared with below, the median (OR=3.44 (95% CI 1.33 to 8.87), p-trend=0.014). The risk of developing late AMD was decreased, but not statistically significant, among participants with a Prudent pattern score above, as compared with below, the median (OR=0.51 (95% CI 0.22 to 1.18), p-trend=0.054).

CONCLUSIONS

Diet patterns were not significantly associated with incident any or incident early AMD. However, consumption of a Western pattern diet may be a risk factor for development of late AMD.

Recent theranostic paradigms for the management of Age-related macular degeneration

Degenerative diseases of eye like Age-related macular degeneration (AMD), that affects the central portion of the retina (macula), is one of the leading causes of blindness worldwide especially in the elderly population. It is classified mainly as wet and dry form. With expanding knowledge about the underlying pathophysiology of the disease, various treatment strategies are being employed to halt the course of the disease progression. Hitherto, there is no ideal therapy which can cure the disease completely, and targeting the posterior segment of the eye is yet another challenge. The purpose of this review is to summarize the recent advances in the management and treatment stratagems (therapies, delivery systems and diagnostic tools) pertaining to AMD viz. molecular targeting, stem cell therapy, nanotechnology and exosomes with special reference to newer technologies like artificial intelligence and 3D printing. Furthermore, the role of diet and nutritional supplements in the prevention and treatment of the disease has also been highlighted. The alarming increase in the said disorder around the globe demands exhaustive research and investigations in the treatment zone. This review thus additionally directs the attention towards the challenges and future perspectives of different treatment approaches for AMD.

Vitamin D Levels in Young Adult Cataract Patients: A Case-Control Study

OBJECTIVE

We aimed to investigate whether a relationship is present between early cataract formation and vitamin D in young adults.

METHODS

A total of 37 cataract patients (18 males and 19 females) and 53 healthy participants (27 males and 26 females) under the age of 60 years were included in this study. The 25-OH vitamin D values were measured in all subjects and the mean vitamin D levels compared between the 2 groups. Additionally, the differences between the vitamin D levels of the genders in both groups were investigated.

RESULTS

The mean age of the study group was 48.1 ± 8.5 (range 33-59) years, and the mean age of the control group was 49.3 ± 7.8 (range 31-59) years (p = 0.48 and p = 0.83). The mean vitamin D level was 15.6 ± 8.4 ng/mL in the study group and 20.8 ± 7.1 ng/mL in the healthy subjects (p = 0.002). Among the females, the vitamin D level was 10.6 ± 4.7 ng/mL in the study group and 18.1 ± 6.4 ng/mL in the control group (p = 0.0001). No significant difference was found between the groups among the males (p = 0.24).

CONCLUSION

We found vitamin D deficiency to be associated with early age-related cataract in a statistically significant manner. We believe it is worth investigating the reason for this concurrence with large longitudinal studies.

Association of Dietary and Supplementary Calcium Intake With Age-Related Macular Degeneration: Age-Related Eye Disease Study Report 39

Importance

Previous studies of the role of dietary and supplementary calcium in age-related macular degeneration (AMD) have produced mixed results, suggesting that supplementation and decreased dietary intake are both harmful.

Objective

To evaluate the association of baseline dietary and supplementary calcium intake with progression of AMD.

Design, Setting, and Participants

This study involved secondary analyses of participants enrolled in the Age-Related Eye Disease Study (AREDS). The AREDS study (1992-2001) enrolled patients from academic and community-based retinal practices in the United States. Men and women with varying severity of AMD were included. Data analysis for this article occurred from September 2015 to December 2018.

Exposures

Baseline self-reported dietary or supplementary calcium intake.

Main Outcomes and Measures

Development of late AMD, geographic atrophy (central or noncentral), or neovascular AMD detected on centrally graded baseline and annual fundus photographs.

Results

A total of 4751 participants were included (mean [SD] age, 69.4 [5.1] years); 4543 (95.6%) were white, and 2655 (55.9%) were female. Compared with those who were in the lowest quintile, the participants in the highest quintile of dietary calcium intake had a lower risk of developing late AMD (hazard ratio [HR], 0.73 [95% CI, 0.59-0.90]), central geographic atrophy (HR, 0.64 [95% CI, 0.48-0.86]), and any geographic atrophy (HR, 0.80 [95% CI, 0.64-1.00]). The participants in the highest tertile of supplementary calcium intake had a lower risk of developing neovascular AMD (HR, 0.70 [95% CI, 0.50-0.97]) compared with those who did not take calcium supplements. When stratified by sex, women in the highest quintile of dietary calcium intake had a lower risk of developing late AMD (HR, 0.73 [95% CI, 0.56-0.97]) compared with those in the lowest quintile. Women in the highest tertile of calcium supplementation had a lower risk of progression to neovascular AMD (HR, 0.67 [95% CI, 0.48-0.94]) compared with those who did not take calcium supplements. Similar findings were found in men for dietary calcium. Too few men took calcium supplements to allow for analyses.

Conclusions and Relevance

In this secondary analysis, higher levels of dietary and supplementary calcium intake were associated with lower incidence of progression to late AMD in AREDS participants. The results may be owing to uncontrolled confounding or chance and should be considered hypothesis development requiring additional study.

The Possible Link Between Vitamin D Levels and Exudative Age-related Macular Degeneration

Objectives

We sought to evaluate the possible correlation between serum vitamin D levels and exudative age-related macular degeneration (AMD).

Methods

We conducted a cross-sectional study including 95 patients with exudative AMD and 95 healthy age- and sex-matched controls. The participants’ serum 25-hydroxyvitamin D3 (25(OH)D3) levels were measured, and the results were classified into three categories: deficient (< 20.0 ng/mL), insufficient (20.1–29.9 ng/mL), and sufficient (>30.0 ng/mL). We compared serum 25(OH)D3 levels between the two study groups and the AMD ratio between the patients with deficient serum 25(OH)D3 levels and those with levels in the sufficient and insufficient ranges.

Results

The median 25(OH)D3 levels were significantly lower in patients with AMD compared to the control subjects (p = 0.042). The frequencies of patients with AMD among the vitamin D categories were statistically significant (p = 0.043). Subgroup analysis showed that the frequency of patients with AMD and deficient vitamin D levels was significantly higher than that found in the patients who had sufficient and/or insufficient ranges of vitamin D levels (55.0% vs. 36.0%, p = 0.043, respectively).

Conclusions

Serum 25(OH)D3 levels may have an impact on the neovascular type of AMD. As 25(OH)D3 levels decrease, the frequency of AMD increases.

Serum 25-Hydroxyvitamin D Concentrations and Incidence of Age-Related Macular Degeneration: The Atherosclerosis Risk in Communities Study

Purpose

To investigate the association between serum 25-hydroxyvitamin D (25[OH]D) concentrations at visit 2 (1990–1992) and the 18-year incidence of age-related macular degeneration (AMD) between visit 3 (1993–1995) and visit 5 (2011–2013).

Methods

This prospective analysis was conducted in a subset of participants (n = 1225) from the Atherosclerosis Risk in Communities Study. We evaluated the incidence of any, early, and late AMD from visit 3 to 5. The 25(OH)D concentrations were assessed in 2012–2013 by using stored serum from visit 2. Retinal fundus photographs taken at both visits were graded side by side to determine the incidence of AMD. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for incident AMD outcomes during 18 years of follow-up (1993–1995 to 2011–2013) by tertile of 25(OH)D adjusted for age, race, and smoking status. P for linear trend was estimated by using continuous 25(OH)D concentrations. Sensitivity analyses applied inverse probability weights to account for selection to have eye photographs, death, and loss to follow-up.

Results

There was a decreased odds of any incident AMD (n = 139) and large, soft drusen (n = 80) in 25(OH)D tertile 3 versus 1, with OR (95% CI) = 0.57 (0.36–0.90), P trend = 0.11 and with 0.52 (0.28–0.93), P trend = 0.18, respectively. Applying sampling weights attenuated these results to 0.66 (0.38–1.16), P trend = 0.32 (any incident AMD) and 0.54 (0.27–1.09), P trend = 0.36 (large, soft drusen), respectively, suggesting these associations may be biased by loss to follow-up and sampling for retinal photographs at visit 5. No statistically significant results were observed with pigmentary abnormalities (n = 46) or incident late AMD (n = 26).

Conclusions

High 25(OH)D concentrations, approximately >70 nM, may be associated with decreased odds of incident early AMD.

Vitamin D Attenuates Oxidative Damage and Inflammation in Retinal Pigment Epithelial Cells

Age-related macular degeneration (AMD), the most common visual disorder in elderly people, is characterized by the formation of deposits beneath the retinal pigment epithelium (RPE) and by dysfunction of RPE and photoreceptor cells. The biologically active form of vitamin D, 1,25-(OH)2D3 (VITD), is categorized as a multifunctional steroid hormone that modulates many transcriptional processes of different genes and is involved in a broad range of cellular functions. Epidemiological and genetic association studies demonstrate that VITD may have a protective role in AMD, while single nucleotide polymorphisms in the vitamin D metabolism gene (CYP24A1) increase the risk of AMD. However, the functional mechanisms of VITD in AMD are not fully understood. In the current study, we investigated the impact of VITD on H₂O₂-induced oxidative stress and inflammation in human RPE cells. We demonstrate that exposure to H₂O₂ caused significantly reduced cell viability, increased production of reactive oxygen species (ROS), lowered expression of antioxidant enzymes and enhanced inflammation. VITD exposure notably counteracted the above H₂O₂-induced effects. Our data suggest that VITD protects the RPE from oxidative damage and elucidate molecular mechanisms of VITD deficiency in the development of AMD.

Association of Serum 25-Hydroxyl Vitamin D Deficiency and Age-Related Cataract: A Case-Control Study

Purpose

To study the relation between the serum 25-hydroxyl vitamin D (OH D) level and the occurrence of age-related cataract in a case-control study.

Patients and Methods

325 cataract patients and 385 control individuals of both sexes were examined for the 25-OH D level using the chemiluminescent microparticle immunoassay (CMIA) technology.

Results

Mean 25-OH D level in cataract patients was 7.6 ± 5.5 ± 11.2 ng/mL and median was 5.6 (2.6-31.9), while in the control group, mean 25-OH D level was 18.5 ± 9.6 ng/mL and median was 17.8 (3.4-37.8) (p value < 0.001). There was a statistically significant difference among the different types of cataracts with the lowest level in nuclear cataract.

Conclusion

25-OH D levels in all enrolled individuals were below the reference levels with a severe deficiency in cataract patients. These results might highlight the role of deficiency of 25-OH D in age-related cataract patients.

The association between blood vitamins D and E with age-related macular degeneration: A pilot study

Background

This study was aimed to evaluate the association of serum vitamins D and E level with age-related macular degeneration (AMD).

Methods

This pilot study was performed in two groups of 15 patients in treatment group and 15 patients in control group. Measurements of blood factors [such as C-reactive protein (CRP) and high-density lipoprotein (HDL)] were performed after 12 h of fasting. To measure vitamins D and E, the serum was isolated from 5 cc blood samples.

Results

HDL was higher in the control group as compared with the AMD group. However, no significant difference was found between the two groups (p = 0.08). On the other hand, serum vitamin E in the AMD group was remarkably higher as compared to the control group (p < 0.002). However, no significant difference was found in serum vitamin D levels between the two groups (p = 0.662). Our findings also revealed that there was no statistically significant relationship between BMI and AMD. Moreover, no significant correlation was determined between serum CRP and AMD (p = 0.96).

Conclusions

Our data indicated that none provides evidence for associations between AMD and serum vitamin D levels. The association between vitamin D and AMD requires further investigations in a large population studies, to elucidate whether vitamin D deficiency can be an important risk factor for AMD.

Nutritional effect on age-related cataract formation and progression

PURPOSE OF REVIEW

To provide a comprehensive summary of the latest evidence-based data on nutrients linked to the pathogenesis of cataract formation and progression.

RECENT FINDINGS

This summary of peer-reviewed publications emphasizes the ongoing effort to modulate the cataractogenous process through nutrition, and points at an only weak evidence for the contribution of a specific nutrient to this process. Although observational studies successfully demonstrated a positive correlation between specific nutrients intake and age-related cataract, such evidence was usually lacking in following interventional studies. Three metanalyses point towards a beneficial effect of high intake of vitamin C, vitamin E and vitamin A on the risk of age-related cataract. New studies point at a protective effect of a high intake of vitamin K1 and vitamin D but negate the influence of Mediterranean diet or an overall high dairy consumption on the progression of cataract in a subgroup of patients. Sterols are candidate nutrients for future investigation.

SUMMARY

Nutrition rich in fruits and vegetables, and a high dietary intake of vitamins A, C, D, E and K1 may be inversely associated with the risk of age-related cataract. More studies involving patients in a wide range of nutritional status are required to establish the long-term benefit of nutritional supplements.

Association Between Osteoporosis and Age-Related Macular Degeneration: The Korea National Health and Nutrition Examination Survey

Purpose

Previous studies have reported a possible link between low bone mineral density and AMD. The aim of the present study was to investigate the association between osteoporosis and AMD in a South Korean cohort.

Methods

This cross-sectional, nationwide study included 3496 women and 2789 men who had participated in the Korean National Health and Nutrition Examination Survey from 2008 to 2011. All retinal photographs were graded using an international classification and grading system. Osteoporosis was assessed using dual-energy x-ray absorptiometry. Multivariate logistic regression analysis was performed to examine the relationship between osteoporosis and AMD after adjustment for potential confounders, including age, the body mass index, dietary calcium intake, and the serum vitamin D level. The odds ratios (OR) for other aging-related eye diseases, including cataract, open-angle glaucoma, and diabetic retinopathy, were analyzed in accordance with the presence of osteoporosis.

Results

Multivariate regression analysis revealed that osteoporosis was significantly associated with all types of AMD (early and late: OR, 1.31; P = 0.017) and early AMD (OR, 1.36; P = 0.007) in women. Late AMD was not associated with osteoporosis (OR, 0.84; P = 0.670). In men, osteoporosis was not associated with any type of AMD. In women, the status of osteoporosis in the femoral neck showed a linear relationship with AMD (P = 0.004). Although osteoporosis was associated with AMD in women, it showed no association with other age-related eye diseases; this suggested a disease-specific association.

Conclusions

Our findings suggest that osteoporosis plays a role in AMD development in postmenopausal women.

Negative Regulators of Angiogenesis, Ocular Vascular Homeostasis, and Pathogenesis and Treatment of Exudative AMD

Angiogenesis, the formation of new blood vessels from pre-existing capillaries, is very tightly regulated and normally does not occur except during developmental and reparative processes. This tight regulation is maintained by a balanced production of positive and negative regulators, and alterations under pathological conditions such as retinopathy of prematurity, diabetic retinopathy, and age-related macular degeneration can lead to growth of new and abnormal blood vessels. Although the role of proangiogenic factors such as vascular endothelial growth factor has been extensively studied, little is known about the roles of negative regulators of angiogenesis in the pathogenesis of these diseases. Here, we will discuss the role of thrombospondin-1 (TSP1), one of the first known endogenous inhibitors of angiogenesis, in ocular vascular homeostasis, and how its alterations may contribute to the pathogenesis of age-related macular degeneration and choroidal neovascularization. We will also discuss its potential utility as a therapeutic target for treatment of ocular diseases with a neovascular component.

Non-musculoskeletal benefits of vitamin D

The aim of this study is to determine and critically evaluate the plausible relationships of vitamin D with extra-skeletal tissues in humans. Severe vitamin D deficiency results in rickets in children and osteomalacia in adults; these beneficial effects in the musculoskeletal system and certain physiological functions are well understood. Nevertheless, mounting reports support additional beneficial effects of vitamin D, outside the musculoskeletal system. This review explores the recent advances in knowledge about the non-skeletal effects of vitamin D. Peer-reviewed papers were extracted from research databases using key words, to assess correlations between vitamin D and extra-skeletal diseases and conditions. As per the guidelines of the Preferred Reporting Items for Systematic Reviews (PRISMA); general interpretations of results are included; taking into consideration the broader evidence and implications. This review summarizes current knowledge of the effects of vitamin D status on extra-skeletal tissues with special attention given to relationships between vitamin D status and various diseases commonly affecting adults; the effects of intervention with vitamin D and exposure to sunlight. Evidence suggests that vitamin D facilitates the regulation of blood pressure; and cardiac; endothelial; and smooth muscle cell functions; playing an important role in cardiovascular protection. In addition; 1,25(OH)₂D improves immunity; subdues inflammation; and reduces the incidence and severity of common cancers; autoimmune diseases and infectious diseases. Almost all adequately powered; epidemiological and biological studies that use; adequate doses of vitamin D supplementation in D-deficient populations have reported favorable outcomes. These studies have concluded that optimizing 25(OH)D status improves the functionality of bodily systems; reduces comorbidities; improves the quality of life; and increases survival. Although accumulating evidence supports biological associations of vitamin D sufficiency with improved physical and mental functions; no definitive evidence exists from well-designed; statistically powered; randomized controlled clinical trials. Nevertheless, most studies point to significant protective effects of vitamin D in humans when the minimum 25(OH)D serum level exceeds 30ng/mL and is maintained throughout the year.

Vitamin D and Age-Related Macular Degeneration

In recent years, the relationship between vitamin D and health has received growing attention from the scientific and medical communities. Vitamin D deficiencies have been repeatedly associated with various acute and chronic diseases, including age-related macular degeneration (AMD). Its active metabolite, 1α,25-dihydoxy vitamin D, acts as a modulator of cell proliferation, differentiation and apoptosis, and cumulative data from experimental and observational studies suggest that relatively a lower vitamin D status could be a potential risk factor for the development of early and/or late AMD. Herein, we made a narrative review of the mechanisms linking a potential role of vitamin D with the current concepts of AMD pathophysiology.

Associations Between Vitamin D Intake and Progression to Incident Advanced Age-Related Macular Degeneration

Purpose

There is growing evidence of the importance of nutrition in age-related macular degeneration (AMD), but no prospective studies have explored the impact of vitamin D. We evaluated the association between vitamin D intake and progression to advanced AMD.

Methods

Among 2146 participants (3965 eyes), 541 (777 eyes) progressed from early or intermediate AMD to advanced disease (mean follow-up: 9.4 years) based on ocular imaging. Nutrients were log transformed and calorie adjusted. Survival analysis was used to assess associations between incident advanced disease and vitamin D intake. Neovascular disease (NV) and geographic atrophy (GA) were evaluated separately. Combined effects of dietary vitamin D and calcium were assessed based on high or low consumption of each nutrient.

Results

There was a lower risk of progression to advanced AMD in the highest versus lowest quintile of dietary vitamin D intake after adjustment for demographic, behavioral, ocular, and nutritional factors (hazard ratio [HR]: 0.60; 95% confidence interval [CI]: 0.43–0.83; P trend = 0.0007). Similar results were observed for NV (HR: 0.59; 95% CI: 0.39–0.89; P trend = 0.005) but not GA (HR: 0.83; 95% CI: 0.53–1.30; P trend = 0.35). A protective effect was observed for advanced AMD among participants with high vitamin D and low calcium compared to the group with low levels for each nutrient (HR: 0.67; 95% CI: 0.50–0.88; P = 0.005). When supplement use was considered, the effect was in the protective direction but was not significant.

Conclusions

A diet rich in vitamin D may prevent or delay progression to advanced AMD, especially NV. Additional exploration is needed to elucidate the potential protective role of vitamin D and its contribution to reducing visual loss.

Recent developments in age-related macular degeneration: a review

Background

Visual impairment in elderly people is a considerable health problem that significantly affects quality of life of millions worldwide. The magnitude of this issue is becoming more evident with an aging population and an increasing number of older individuals.

Objective

The objective of this article was to review the clinical and pathological aspects of age-related macular degeneration (AMD), diagnostic tools, and therapeutic modalities presently available or underway for both atrophic and wet forms of the disease.

Methods

An online review of the PubMed database was performed, searching for the key words. The search was limited to articles published since 1980 to date.

Results

Several risk factors have been linked to AMD, such as age (>60 years), lifestyle (smoking and diet), and family history. Although the pathogenesis of AMD remains unclear, genetic factors have been implicated in the condition. Treatment for atrophic AMD is mainly close observation, coupled with nutritional supplements such as zinc and antioxidants, whereas treatment of wet AMD is based on targeting choroidal neovascular membranes.

Conclusion

Identification of modifiable risk factors would improve the possibilities of preventing the progression of AMD. The role of anti-vascular endothelial growth factor (anti-VEGF) agents has transformed the therapeutic approach of the potentially blinding disease “wet AMD” into a more favorable outcome.

Systemic and ocular fluid compounds as potential biomarkers in age-related macular degeneration

Biomarkers can help unravel mechanisms of disease and identify new targets for therapy. They can also be useful in clinical practice for monitoring disease progression, evaluation of treatment efficacy, and risk assessment in multifactorial diseases, such as age-related macular degeneration (AMD). AMD is a highly prevalent progressive retinal disorder for which multiple genetic and environmental risk factors have been described, but the exact etiology is not yet fully understood. Many compounds have been evaluated for their association with AMD. We performed an extensive literature review of all compounds measured in serum, plasma, vitreous, aqueous humor, and urine of AMD patients. Over 3600 articles were screened, resulting in more than 100 different compounds analyzed in AMD studies, involved in neovascularization, immunity, lipid metabolism, extracellular matrix, oxidative stress, diet, hormones, and comorbidities (such as kidney disease). For each compound, we provide a short description of its function and discuss the results of the studies in relation to its usefulness as AMD biomarker. In addition, biomarkers identified by hypothesis-free techniques, including metabolomics, proteomics, and epigenomics, are covered. In summary, compounds belonging to the oxidative stress pathway, the complement system, and lipid metabolism are the most promising biomarker candidates for AMD. We hope that this comprehensive survey of the literature on systemic and ocular fluid compounds as potential biomarkers in AMD will provide a stepping stone for future research and possible implementation in clinical practice.

Modulatory effects of 1,25-dihydroxyvitamin D3 on eye disorders: A critical review

Many studies have shown that the presence of 1,25-dihydroxyvitamin D3 in the eye is able to modulate inflammatory responses. In fact, it has been demonstrated that topical administration of vitamin D3 inhibits Langerhans cells migration from the central cornea, corneal neovascularization, and production of cytokines (i.e., interleukin-1-6-8) in experimental animals. Moreover, both in vitro and in vivo studies have demonstrated that vitamin D is a potent inhibitor of retinal neovascularization. It has been shown that calcitriol, the biologically active form of vitamin D, inhibits angiogenesis both in cultured endothelial cells and in retinas from guinea pigs with retinoblastoma or oxygen-induced ischemic retinopathy. In addition, it seems that this compound is able to prevent the progression from early to neovascular age-related macular degeneration (AMD) and, at the same time, to down-regulate the characteristic inflammatory cascade at the retinal pigment epithelium-choroid interface due to its anti-inflammatory and immunomodulatory capabilities. Furthermore, 1,25-dihydroxyvitamin D3 and its analogue, 2-methylene-19-nor-1,25-dihydroxyvitamin D3, are able to modulate intraocular pressure (IOP) through gene expression. Several studies have suggested a role in glaucoma and diabetic retinopathy therapies for vitamin D3. In conclusion, this review summarizes our current knowledge on the potential use of vitamin D3 in the protection and treatment of ocular diseases in ophthalmology.

Vitamin D Status and Prevalent Early Age-Related Macular Degeneration in African Americans and Caucasians: The Atherosclerosis Risk in Communities (ARIC) Study

OBJECTIVES

Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort.

DESIGN

This was a cross-sectional study.

SETTING

This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995.

PARTICIPANTS

There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data.

MEASUREMENTS

Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted.

RESULTS

The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant.

CONCLUSIONS

Vitamin D status was not associated with early AMD in this cohort sample.

Vitamin D Activation and Function in Human Corneal Epithelial Cells During TLR-Induced Inflammation

PURPOSE

Vitamin D is recognized to be an important modulator of the immune system. In the eye, studies have shown that deficiencies and genetic differences in vitamin D-related genes have a significant impact on the development of various ocular diseases. Our current study examines the ability of human corneal epithelial cells (HCEC) to activate vitamin D and the effect of vitamin D treatment on antimicrobial peptide production and cytokine modulation during inflammation, with the ultimate goal of using vitamin D therapeutically for corneal inflammation.

METHODS

Human corneal epithelial cells were treated with 10-7M vitamin D3 (D3) or 25-hydroxyvitamin D3 (25D3) for 24 hours and 1,25-dihydroxyvitamin D3 (1,25D3) detected by immunoassay. Human cathelicidin (LL-37) expression was examined by RT-PCR, immunoblot, and immunostaining following 1,25D3 treatment and antimicrobial activity of 1,25D3-treated cells was determined. Cells were stimulated with TLR3 agonist polyinosinic-polycytidylic acid (Poly[I:C]) for 24 hours and cytokine levels measured by RT-PCR, ELISA, and Luminex. Immunostaining determined expression of vitamin D receptor (VDR) and retinoic acid inducible gene-1 receptor (RIG-1) as well as NF-κB nuclear translocation.

RESULTS

When treated with inactive vitamin D metabolites, HCEC produced active 1,25D3, leading to enhanced expression of the antimicrobial peptide, LL-37, dependent on VDR. 1,25-D3 decreased the expression of proinflammatory cytokines (IL-1β, IL-6, TNFα, and CCL20) and MMP-9 induced by Poly(I:C) as well as pattern recognition receptor expression (TLR3, RIG-1, MDA5). However, early activation of NF-κB was not affected.

CONCLUSIONS

These studies demonstrate the protective ability of vitamin D to attenuate proinflammatory mediators while increasing antimicrobial peptides and antipseudomonas activity in corneal cells, and further our knowledge on the immunomodulatory functions of the hormone.

Circulating vitamin D concentration and age-related macular degeneration: Systematic review and meta-analysis

Vitamin D may be involved in ocular function in older adults, but there is no current consensus on a possible association between circulating concentrations of 25-hydroxyvitamin D (25OHD) and the occurrence of age-related macular degeneration (AMD). Our objective was to systematically review and quantitatively assess the association of circulating 25OHD concentration with AMD. A Medline search was conducted in November 2015, with no date limit, using the MeSH terms "Vitamin D" OR "Vitamin D deficiency" OR "Ergocalciferols" OR 'Cholecalciferol' combined with "Age-related macular degeneration" OR "Macular degeneration" OR "Retinal degeneration" OR "Macula lutea" OR "Retina". Fixed and random-effects meta-analyses were performed to compute (i) standard mean difference in 25OHD concentration between AMD and non-AMD patients; (ii) AMD risk according to circulating 25OHD concentration. Of the 243 retrieved studies, 11 observational studies-10 cross-sectional studies and 1 cohort study-met the selection criteria. The number of participants ranged from 65 to 17,045 (52-100% women), and the number with AMD ranged from 31 to 1440. Circulating 25OHD concentration was 15% lower in AMD compared with non-AMD on average. AMD was inversely associated with the highest 25OHD quintile compared with the lowest (summary odds ratio (OR)=0.83 [95%CI:0.71-0.97]), notably late AMD (summary OR=0.47 [95%CI:0.28-0.79]). Circulating 25OHD<50nmol/L was also associated with late-stage AMD (summary OR=2.18 [95%CI:1.34-3.56]), an association that did not persist when all categories of AMD were considered (summary OR=1.26 [95%CI:0.90-1.76]). In conclusion, this meta-analysis provides evidence that high 25OHD concentrations may be protective against AMD, and that 25OHD concentrations below 50nmol/L are associated with late AMD.

Serum 25-Hydroxyvitamin D Levels and Dry Eye Syndrome: Differential Effects of Vitamin D on Ocular Diseases

Purpose

To investigate associations between serum 25-hydroxyvitamin D levels and dry eye syndrome (DES), and to evaluate the differential effect of vitamin D on ocular diseases including age-related macular disease (AMD), diabetic retinopathy (DR), cataract, and DES.

Methods

A total of 16,396 participants aged >19 years were randomly selected from the Korean National Health and Nutrition Examination Survey. All participants participated in standardized interviews, blood 25-hydroxyvitamin D level evaluations, and comprehensive ophthalmic examinations. DES was defined by a history of clinical diagnosis of dry eyes by a physician. The association between vitamin D and DES was compared to the associations between vitamin D and AMD, DR, cataract, and DES from our previous studies.

Results

The odds of DES non-significantly decreased as the quintiles of serum 25-hydroxyvitamin D levels increased (quintile 5 versus 1, OR = 0.85, 95%CI: 0.55–1.30, P for trend = 0.076) after adjusting for potential confounders including age, sex, hypertension, diabetes, smoking status, and sunlight exposure times. The relative odds of DES (OR = 0.70, 95% CI: 0.30–1.64) and cataract (OR = 0.76, 95% CI: 0.59–0.99) were relatively high, while those of DR (OR = 0.37, 95% CI: 0.18–0.76) and late AMD (OR = 0.32, 95% CI: 0.12–0.81) were lower in men.

Conclusions

The present study does not support an association between serum 25-hydroxyvitamin D levels and DES. The preventive effect of serum 25-hydroxyvitamin D may be more effective for DR and late AMD than it is for cataract and DES.

Protection against oxidative stress by vitamin D in cone cells

Photoreceptor degeneration (PD) refers to a group of heterogeneous outer retinal dystrophies characterized by the death of photoreceptors. Both oxidative stress and inflammation are involved in the pathogenesis of PD. We investigate whether vitamin D has a potential for the treatment of PD by evaluating the anti-oxidative stress and anti-inflammatory properties of the active form of vitamin D3 , 1,α, 25-dihydroxyvitamin D3 , in a mouse cone cell line, 661W. Mouse cone cells were treated with H2 O2 or a mixture of H2 O2 and vitamin D; cell viability was determined. The production of reactive oxygen species (ROS) in treated and untreated cells was measured. The expression of key anti-oxidative stress and inflammatory genes in treated and untreated cells was determined. Treatment with vitamin D significantly increased cell viability and decreased ROS production in 661W cells under oxidative stress induced by H2 O2 . H2 O2 treatment in 661W cells can significantly down-regulate the expression of antioxidant genes and up-regulate the expression of neurotoxic cytokines. Vitamin D treatment significantly reversed these effects and restored the expression of antioxidant genes. Vitamin D treatment also can block H2 O2 induced oxidative damages. The data suggested that vitamin D may offer a therapeutic potential for patients with PD.

Geo-Epidemiology of Age-Related Macular Degeneration: New Clues Into the Pathogenesis

PURPOSE

To evaluate the demographic, geographic, and race-related variables that account for geographic variability in prevalence rates of age-related macular degeneration (AMD).

DESIGN

Systematic review, meta-regression, and decision-tree analysis.

METHODS

A systematic literature review of PubMed, Medline, Web of Science, and Embase databases identified population-based studies on the prevalence of AMD published before May 2014. Only population-based studies that took place in a spatially explicit geographic area that could be geolocalized, and used retinal photographs and standardized grading classifications, were included. Latitude and longitude data (geolocalization) and the mean annual insolation for the area where survey took place were obtained. Age-standardized prevalence rates across studies were estimated using the direct standardization method. Correlations between the prevalence of AMD and longitude and latitude were obtained by regression analysis. A hierarchical Bayesian meta-regression approach was used to assess the association between the prevalence of AMD and other relevant factors. We further investigated the interplay between location and these factors on the prevalence of AMD using regression based on conditional-inference decision trees.

RESULTS

We observed significant inverse correlations between latitude or longitude, and crude or age-standardized prevalence rates, of early and late AMD (P < .001). Metaregression analysis showed that insolation, latitude, longitude, age, and race have a significant effect on the prevalence rates of early and late AMD (P < .001). Decision-tree analysis identified that the most important predictive variable was race for early AMD (P = .002) and insolation for late AMD (P = .001).

CONCLUSIONS

Geographic position and insolation are key factors in the prevalence of AMD.

Association between vitamin D status and age-related macular degeneration by genetic risk

IMPORTANCE

Deficient 25-hydroxyvitamin D (25[OH]D) concentrations have been associated with increased odds of age-related macular degeneration (AMD).

OBJECTIVE

To examine whether this association is modified by genetic risk for AMD and whether there is an association between AMD and single-nucleotide polymorphisms of genes involved in vitamin D transport, metabolism, and genomic function.

DESIGN, SETTING, AND PARTICIPANTS

Postmenopausal women (N = 913) who were participants of the Carotenoids in Age-Related Eye Disease Study (CAREDS) (aged 54 to <75 years) with available serum 25(OH)D concentrations (assessed October 1, 1993, to December 31, 1998), genetic data, and measures of AMD (n = 142) assessed at CAREDS baseline from May 14, 2001, through January 31, 2004, were studied.

MAIN OUTCOMES AND MEASURES

Prevalent early or late AMD was determined from graded, stereoscopic fundus photographs. Logistic regression was used to estimate odds ratios (ORs) and 95% CIs for AMD by the joint effects of 25(OH)D (<12, ≥12 to <20, ≥20 to <30, and ≥30 ng/mL) and risk genotype (noncarrier, 1 risk allele, or 2 risk alleles). The referent group was noncarriers with adequate vitamin D status (≥30 ng/mL). Joint effect ORs were adjusted for age, smoking, iris pigmentation, self-reported cardiovascular disease, self-reported diabetes status, and hormone use. Additive and multiplicative interactions were assessed using the synergy index (SI) and an interaction term, respectively. To examine the association between AMD and variants in vitamin D-related genes, age-adjusted ORs and 95% CIs were estimated using logistic regression.

RESULTS

Among the 913 women, 550 had adequate levels of vitamin D (≥20 ng/mL), 275 had inadequate levels (≥12 to <20 mg/mL), and 88 had deficient levels (<12 ng/mL). A 6.7-fold increased odds of AMD (95% CI, 1.6-28.2) was observed among women with deficient vitamin D status (25[OH]D <12 ng/mL) and 2 risk alleles for CFH Y402H (SI for additive interaction, 1.4; 95% CI, 1.1-1.7; P for multiplicative interaction = .25). Significant additive (SI, 1.4; 95% CI, 1.1-1.7) and multiplicative interactions (P = .02) were observed for deficient women with 2 high-risk CFI (rs10033900) alleles (OR, 6.3; 95% CI, 1.6-24.2). The odds of AMD did not differ by genotype of candidate vitamin D genes.

CONCLUSIONS AND RELEVANCE

In this study, the odds of AMD were highest in those with deficient vitamin D status and 2 risk alleles for the CFH and CFI genotypes, suggesting a synergistic effect between vitamin D status and complement cascade protein function. Limited sample size led to wide CIs. Findings may be due to chance or explained by residual confounding.

The Relationship Between Serum 25-Hydroxyvitamin D Levels and Nuclear Cataract in the Carotenoid Age-Related Eye Study (CAREDS), an Ancillary Study of the Women's Health Initiative

PURPOSE

To investigate the relationship between serum 25-hydroxyvitamin D (25[OH]D) levels and nuclear cataract among participants of the Carotenoids in Age-Related Eye Disease Study (CAREDS), an ancillary study of the Women's Health Initiative (WHI) Observational Study (OS).

METHODS

Nuclear cataract was assessed from slit lamp photographs (2001-2004) taken 6 years after collecting serum analyzed for 25(OH)D levels at WHI baseline (1994-1998) in 1278 CAREDS participants age 50 to 79 years. Multivariate (age, iris color, smoking, pulse pressure) odds ratios (ORs) for nuclear cataract (nuclear opacities > level 4 or cataract extraction) by quintiles of serum 25(OH)D were estimated using logistic regression.

RESULTS

No significant association was observed between serum 25(OH)D and nuclear cataract among women of all ages (age-adjusted OR [95% confidence interval (CI)] 0.97 [0.65-1.45]). However, there was a significant age interaction (P for interaction = 0.04). There were no significant associations in the women 70 years or older. In women younger than 70 years, we observed an inverse association between serum 25(OH)D and nuclear cataract (multivariate adjusted ORs [95% CI] 0.54 [0.29-0.99] and 0.66 [0.36-1.20] for quintiles 4 and 5 vs. 1, respectively; P = 0.03). Further adjustment for 25(OH)D determinants (body mass index, vitamin D intake, and UVB exposure) attenuated this association.

CONCLUSIONS

Serum 25(OH)D levels were unrelated to nuclear opacities in this study sample. However, exploratory analyses suggest a protective association in women younger than 70 years. Further investigations of the relationship between vitamin D and nuclear lens opacities are warranted.

Vitamin D Deficiency in Community-Dwelling Elderly Is Not Associated with Age-Related Macular Degeneration

BACKGROUND

Elderly persons are at elevated risk of vitamin D deficiency, which is involved in various health problems. However, its relation with age-related macular degeneration (AMD) is debated.

OBJECTIVES

We investigated factors associated with plasma 25-hydroxyvitamin D [25(OH)D] deficiency and the associations between plasma 25(OH)D concentrations and AMD in elderly subjects.

METHODS

Antioxydants, Lipides Essentiels, Nutrition et maladies OculaiRes (ALIENOR) is a population-based study on eye diseases performed in elderly residents of Bordeaux, France. Plasma 25(OH)D concentrations were assessed from blood samples and categorized as <25 nmol/L (deficiency), 25-49 nmol/L (insufficiency), or ≥50 nmol/L (sufficiency). AMD was classified as: no AMD, early AMD, and late AMD. Associations between baseline characteristics and plasma 25(OH)D status were examined with multinomial logistic regression analysis. Associations between AMD and plasma 25(OH)D status were estimated using generalized estimating equation logistic regressions.

RESULTS

Six hundred ninety-seven subjects with complete data were included. The prevalence of plasma 25(OH)D deficiency and insufficiency were 27.3% and 55.9%, respectively. In multivariate analysis, 25(OH)D deficiency was significantly associated with older age (P = 0.0007), females (P = 0.0007), absence of physical activity (P = 0.01), absence of vitamin D supplementation (P < 0.0001), higher plasma total cholesterol (P = 0.007), use of fibrates (P < 0.0001), lower alcohol consumption (P = 0.02), and season of blood sampling (P < 0.0001). After adjustment for these covariates and dietary omega-3 polyunsaturated fatty acid intake, smoking, and body mass index, no significant associations were found between early AMD and 25(OH)D insufficiency or deficiency (OR: 0.71, P = 0.12; OR: 0.73, P = 0.23, respectively) or with late AMD (OR: 1.04, P = 0.93; OR: 0.74, P = 0.59, respectively).

CONCLUSION

These findings underline the very high prevalence of plasma 25(OH)D deficiency in this elderly population but do not support a specific role for vitamin D in AMD.