The prevalence and risk factors for age-related macular degeneration in rural-urban India, Sankara Nethralaya Rural-Urban Age-related Macular degeneration study, Report No. 1

Lifestyle factors associated with age-related macular degeneration: Case-control study

BACKGROUND

Age-related macular degeneration (AMD) is one of the major causes of vision loss in individuals aged ≥ 65 years in developed countries. This study aimed to determine the associations between modifiable risk factors and AMD. This is the first study describing the relationship between lifestyle factors and AMD in the Czech Republic.

METHODS

In this cross-sectional case-control study, 93 AMD cases and 58 controls without AMD and cataract were included. All participants were examined by Optical coherence tomography at the Clinic of Eye Treatment at the University Hospital Brno. Data were collected using a pre-tested self-report questionnaire in a face-to-face interview.

RESULTS

We found significant associations between those who were living in the city (OR 95% CI: 2.19 (1.0-4.6); p = 0,039), with a positive family history of AMD (OR 95% CI: 12.75 (1.6-98.6); p = 0,015), exposure to cigarette smoke (OR 95% CI: 2.72 (1.4-5.4); p = 0,004), and daily exposure to passive smoking (OR 95% CI: 2.29 (1.0-5.1); p = 0,045) and AMD. In men, we found significant associations between daily sunlight exposure (OR 95% CI: 2.98 (1.0-8.5); p = 0,041), short or long sleep duration (OR 95% CI: 3.98 (1.2-13.2); p = 0,024) and AMD. Men daily exposed to sunlight were at a 2.98 times higher risk of AMD than men with less than daily sunlight exposure. Men with short or long sleep duration (< 6 and > 8 h) were at a 3.98 times higher risk of AMD than men with recommended sleep duration of 6-8 h.

CONCLUSIONS

An increased risk of AMD was observed for living in the city, family history of AMD, exposure to cigarette smoke, and daily exposure to passive smoking. Increased risk of AMD was observed for daily sunlight exposure and short or long sleep duration; however, only in men.

Age-Related Macular Degeneration - Therapies and Their Delivery

Age-related macular degeneration (ARMD) is a degenerative ocular disease that is the most important cause of irreversible vision loss in old-aged people in developed countries. Around fifty percent of vision impairments in developed countries are due to ARMD. It is a multifaceted disease that is associated with both genetic and environmental risk factors. The most important treatments option for ARMD includes laser photocoagulation, photodynamic therapy (PDT), Anti-VEGF Injections, and combination therapies. In this review, we also propose that topical ocular drug delivery with nanocarriers has more attention for the treatment of ARMD. The nanocarriers were specially designed for enhanced corneal residential time, prolonged drug release and action, and minimizing the frequency of administrations. Different types of nanocarriers were developed for the topical ocular delivery system, such as nanomicelles, nanoemulsions, nanosuspensions, liposomes, and polymeric nanoparticles. These topical ocular nanocarriers were administered topically, and they can fix the hydrophobic substances, increase solubility and improve the bioavailability of an administered drug. Hence the topical ocular delivery systems with nanocarriers provide a safe and effective therapeutic strategy and promising tool for the treatment of posterior segment ocular diseases ARMD.

Systemic Dyslipidemia in Age-related Macular Degeneration: An Updated Systematic Review and Meta-analysis

Topic

Though lipid and cholesterol dyshomeostasis is thought to contribute to the pathogenesis of age-related macular degeneration (AMD), there is no consensus regarding which elements of systemic lipid homeostasis are perturbed in AMD. In this systematic review and meta-analysis, an update to that performed by Wang et al in 2016, we characterized serum lipoprotein profiles in patients with AMD and its various stages.

Clinical Relevance

These findings may identify novel therapeutic approaches for AMD, a leading cause of blindness among older adults in the industrialized world.

Methods

We used MEDLINE, Embase, and Web of Science to identify articles from database inception to May 2022 that reported blood/serum levels of lipid subspecies (triglycerides [TGs], total cholesterol [TC], low-density lipoprotein [LDL], and high-density lipoprotein [HDL]) in patients with AMD compared with controls. We meta-analyzed the data by generating multilevel random-effects models using restricted maximum likelihood estimation.

Results

Our updated meta-analysis included 56 studies, almost 3 times as many studies as the 2016 meta-analysis with a total of 308 188 participants. There were no significant differences in serum TG, TC, LDL, or HDL between patients with AMD and non-AMD controls. Given significant heterogeneity, we performed subanalyses specifically in patients with early to intermediate nonexudative AMD, advanced nonexudative AMD, and advanced exudative AMD. Compared with non-AMD controls, patients with early to intermediate nonexudative AMD had significantly lower serum TG (standardized mean difference [SMD]: -0.03; 95% confidence interval [95% CI]: -0.06 to -0.01) and higher serum HDL (SMD: 0.07; 95% CI: 0.04-0.11). Patients with advanced exudative AMD had significantly higher serum LDL (SMD: 0.33; 95% CI: 0.04-0.62) compared with non-AMD controls. There were no other significant differences identified.

Conclusion

We found that there is significant heterogeneity in systemic lipoproteins in patients with AMD compared with non-AMD controls. The specific pattern of lipid dyshomeostasis appeared to be distinct based on AMD stage. These findings highlight both the underlying heterogeneity of AMD as well as the presence of distinct pathophysiological mechanisms involved at different stages or subtypes of AMD and may inform the development of novel therapeutic approaches.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Prevalence of age-related macular degeneration and associated factors in Indian cohort in a tertiary care setting

Purpose

To report a big data analysis of risk and protective factors in patients with AMD, as well as report on the age-adjusted prevalence in a geriatric Indian cohort in a hospital setting.

Methods

This retrospective, observational study of all patients older than 60 years of age. Multiple logistic regression was performed for the binary outcome and the presence of AMD. Variables analyzed include age, gender, socioeconomic status, occupation, urban-rural-metropolitan distribution, self-reported history of diabetes mellitus (DM), hypertension (HTN), or coronary artery disease (CAD), ocular comorbidities, history of cataract surgery, and presenting VA. Odds ratios (OR) and 99% confidence intervals were calculated.

Results

Of the 608,171 patients over the age of 60 years who attended our clinics, 1.68% of subjects had a diagnosis of AMD (N = 10,217). Less than half (4,621 of 10,217 with AMD) of them were diagnosed to have dry AMD. Cataract, glaucoma, and diabetic retinopathy were associated with lower risk of AMD. Cataract surgery was associated with the higher risk of AMD (OR = 1.20; 99% CI 1.13-1.29). Smoking was not associated with AMD.

Conclusion

Big data analysis from a hospital setting shows that the prevalence of AMD above the age of 60 years is low. More patients with wet AMD present for treatment compared to dry AMD. Smoking was not associated with AMD in the Indian population. Cataract surgery was associated with higher prevalence of AMD.

Ocular disorders associated with PCSK9 inhibitors: A pharmacovigilance disproportionality analysis

AIMS

To identify and characterize ocular adverse events (oAEs) that are significantly associated with proprotein convertase subtilisin-like/kexin type 9 (PCSK9) inhibitors using the US Food and Drug Administration Adverse Event Reporting System (FAERS).

METHODS

We conducted a disproportionality analysis of PCSK9 inhibitors in the FAERS (01/2004-12/2021). The association between PCSK9 inhibitors and oAEs was evaluated using the information component (IC) and the reporting odds ratio (ROR), and the difference in oAEs between evolocumab and alirocumab was compared using the ROR. Different sensitivity analyses were conducted to evaluate the robustness of results.

RESULTS

A total of 103 531 reports involving at least 1 PCSK9 inhibitor were found in the FAERS. PCSK9 inhibitors were associated with higher reporting of increased lacrimation (IC 0.27 [95% confidence interval {CI} 0.02-0.45]; ROR 1.21 [95% CI 1.04-1.40]), seasonal allergy (IC 0.39 [95% CI 0.04-0.64]; ROR 1.32 [95% CI 1.07-1.62]) and eye operation (IC 0.66 [95% CI 0.04-1.10]; ROR 1.60 [95% CI 1.11-2.30]) compared with the full database, and there was no difference between evolocumab and alirocumab. Sensitivity analyses showed that the disproportionate signals of increased lacrimation disappeared after excluding cases with other lipid-lowering agents in the combined drugs. Except for eye operations, most of these adverse events occurred within 30 days of the first dose, and all 3 oAEs were mostly reported in women and individuals >65 years.

CONCLUSION

This pharmacovigilance study identified a possible signal of ocular disorders associated with PCSK9 inhibitors and encourages paying attention to at-risk populations in PCSK9 inhibitors medication.

The Need for Artificial Intelligence Based Risk Factor Analysis for Age-Related Macular Degeneration: A Review

In epidemiology, a risk factor is a variable associated with increased disease risk. Understanding the role of risk factors is significant for developing a strategy to improve global health. There is strong evidence that risk factors like smoking, alcohol consumption, previous cataract surgery, age, high-density lipoprotein (HDL) cholesterol, BMI, female gender, and focal hyper-pigmentation are independently associated with age-related macular degeneration (AMD). Currently, in the literature, statistical techniques like logistic regression, multivariable logistic regression, etc., are being used to identify AMD risk factors by employing numerical/categorical data. However, artificial intelligence (AI) techniques have not been used so far in the literature for identifying risk factors for AMD. On the other hand, artificial intelligence (AI) based tools can anticipate when a person is at risk of developing chronic diseases like cancer, dementia, asthma, etc., in providing personalized care. AI-based techniques can employ numerical/categorical and/or image data thus resulting in multimodal data analysis, which provides the need for AI-based tools to be used for risk factor analysis in ophthalmology. This review summarizes the statistical techniques used to identify various risk factors and the higher benefits that AI techniques provide for AMD-related disease prediction. Additional studies are required to review different techniques for risk factor identification for other ophthalmic diseases like glaucoma, diabetic macular edema, retinopathy of prematurity, cataract, and diabetic retinopathy.

Intermittent Fasting Is Associated With a Decreased Risk of Age-Related Macular Degeneration

PURPOSE

To investigate the association between intermittent fasting and age-related macular degeneration (AMD) in the general older adult population.

DESIGN

A cross-sectional study using a population-based, government-led survey data, Korean National Health and Nutrition Examination Survey (KNHANES).

METHODS

A total of 4504 individuals aged ≥55 years with comprehensive data including meal frequency and fundus photography were selected using the KNHANES 2015-2018 database. Participants were divided into 2 groups based on breakfast frequency per week; intermittent fasting (nearly 0 time/week) and nonfasting (5-7 times/week) groups. Multiple logistic regression analysis was performed to determine the risk factors for AMD identified by fundus photography.

RESULTS

AMD was identified in 25.1% of total participants. The intermittent fasting group had a decreased risk of AMD compared with the nonfasting group (adjusted odds ratio [aOR] 0.413, 95% CI 0.203-0.841), especially in individuals with a younger age (<70 years, aOR 0.357, 95% CI 0.153-0.833), obesity (aOR 0.663, 95% CI 0.424-1.037), and urban residence (aOR 0.437, 95% CI 0.248-0.769). Increased age (aOR 1.058, 95% CI 1.041-1.076) and serum high-density lipoprotein levels (aOR 1.011, 95% CI 1.002-1.021) were also independent risk factors for AMD.

CONCLUSIONS

Using the population-based survey data, we demonstrated that intermittent fasting by skipping breakfast was significantly associated with a reduced risk of AMD in a representative older adult population, especially in individuals with age <70 years, obesity, and urban residence.

A Study of Correlates of Age-Related Macular Degeneration in Patients Attending a Tertiary Hospital

Background

Age-related macular degeneration (ARMD) is a dreadful vision disease mainly affecting older people and causing permanent blindness if it remains undiagnosed and untreated. This study is particularly carried out to fill the gaps in the literature regarding the association of various systemic and environmental factors with ARMD.

Objective

We aim to study the correlates of age-related macular degeneration in patients attending a tertiary hospital.

Methods

This study is a hospital-based observational case-control study by nature with 260 participants included of ages more than 45 years. The participants were evaluated for risk factors after proper consenting.

Result

Age (56 years), diastolic blood pressure (DBP) of 80 mmHg, smoking cigarette for more than 10 years, sedentary lifestyle, body mass index (BMI) > 29.9 kg/m², sunlight exposure of more than eight hours, and higher lipid levels are determinants of ARMD.

Conclusion

Smoking is the strongest risk factor associated with ARMD, followed by diastolic blood pressure and body mass index. Lipid levels and a sedentary lifestyle have a weaker correlation with ARMD. However, age and gender are the most important determinants among non-modifiable factors.

Association between metformin use and the risk of age-related macular degeneration in patients with type 2 diabetes: a retrospective study

OBJECTIVES

To investigate the effect of metformin on the decreased risk of developing age-related macular degeneration (AMD) in patients with type 2 diabetes mellitus (T2DM) for ≥10 years.

DESIGN

A retrospective study.

PARTICIPANTS

Patients aged ≥50 with a diagnosis of T2DM no less than 10 years were included.

METHODS

Variables predisposing to AMD were reviewed; the potential confounders related to T2DM or AMD were selected from literature records; AMD and diabetic retinopathy (DR) were diagnosed by funduscopy, optical coherence tomography and/or fluorescein angiography. The subgroup analysis was performed in early and late AMD. The protective effect of metformin was evaluated in duration-response and dose-response patterns.

RESULTS

A total of 324 patients (115 metformin non-users and 209 users) were included in the final analysis. AMD was observed in 15.8% of metformin users and 45.2% of metformin non-users (p<0.0001). The ORs for any AMD, early AMD and late AMD present in patients with DR were 0.06 (0.02-0.20), 0.03 (0.00-0.20) and 0.17 (0.04-0.75). The serum high-density lipoprotein level was positively associated with the late AMD risk (p=0.0054). When analysed by the tertiles of cumulative duration, a similarly reduced risk was observed for the second (5-9 years) (OR: 0.24, 95% CI: 0.08 to 0.75) and third tertiles (≥10 years) (OR: 0.22, 95% CI: 0.09 to 0.52) compared with the first tertile (≤4 years).

CONCLUSION

Among patients with T2DM for ≥10 years, metformin users were less likely to develop any AMD and early AMD than non-users; however, the late AMD was not significantly associated with the use of metformin. Also, AMD was less prevalent in patients with DR. The prolonged metformin treatment with a high cumulative dose enhanced the protective effect against AMD. Metformin significantly reduces the AMD risk when the cumulative duration is >5 years.

Revised Glycemic Index for Diagnosing and Monitoring of Diabetes Mellitus in South Indian Population

Aim: To find the optimal threshold of fasting plasma glucose (FPG) and glycated hemoglobin (HbA1c) for diagnosis of diabetes mellitus (DM) and to evaluate the association with diabetic retinopathy (DR) in the South Indian population.

Settings and Design: A retrospective population-based study.

Methods and Materials: A total of 909 newly detected type 2 DM patients were selected from our two previously conducted studies, which include an urban and a rural population of South India. All underwent estimation of fasting, postprandial plasma glucose (PPG), and other biochemical tests. A comprehensive and detailed ophthalmic examination was carried out. The fundi of patients were photographed using 45°, four-field stereoscopic photography. Based on receiver operating characteristic (ROC) curves, sensitivity and specificity were derived.

Results: The optimal cut-off values determined by maximizing the sensitivity and specificity of FPG and HbA1c using the Youden index were ≥ 6.17 mmol/L and ≥ 6.3%, respectively. By distributing the cut-off points into deciles and comparing them to the WHO criteria, we found that our HbA1c level of 6.60% was more than the WHO threshold (6.5%), with higher sensitivity (81.6%) and lower specificity (48.3%). The FPG level of 6.80 mmol/L was lower to the WHO criteria (7 mmol/L) with increased sensitivity (77.0%) and lower specificity (45.7%). Prevalence of DR by HbA1c levels between 6.5% and 6.9% was 15.3%. The prevalence of DR was more in the FPG category between 6.4 and 6.9 mmol/L and ≥ 7.5 mmol/L.

Conclusion: Our population-based data indicate that for the South Indian population HbA1c value of ≥63 % and FPG value of ≥6.17 mmol/L may be optimal for diagnosing DM with a high level of accuracy and will be useful for the identification of mild and moderate DR.

Impact of age-related macular degeneration on diabetic retinopathy: An electronic health record based big data analysis from a tertiary eye centre in South India

Purpose:

To determine whether the presence of age-related macular degeneration (AMD) decreases the risk of diabetic retinopathy.

Methods:

This was a retrospective, case-cohort study performed in patients with a systemic diagnosis of diabetes at a tertiary health care center from May 2011 to April 2020. A total of 43,153 patients (1,024 AMD patients and 42,129 non-AMD patients) were included in the analysis. A total of 1,024 age and diabetes mellitus (DM) duration-matched controls were chosen from the non-AMD group for risk factor analysis. The severity of diabetic retinopathy was compared between the patients with AMD and the patients without AMD.

Results:

Out of the enrolled 43,153 diabetic patients, 26,906 were males and 16,247 were females. A total of 1,024 patients had AMD and 42,129 had no AMD. The mean age of the cohort was 58.60 ± 0.09 years. The overall prevalence of DR was noted to be 22.8% (9,825 out of 43,153 eyes). A significantly lower prevalence of diabetic retinopathy (DR) (23% in non-AMD, 11.4% in AMD, OR = −0.43, P < 0.001), non-proliferative diabetic retinopathy (NPDR) (12% in non-AMD, 8.2% in AMD, OR = −0.66, P < 0.001), and proliferative diabetic retinopathy (PDR) (11% in non-AMD, 3.2% in AMD, OR = −0.27, P < 0.001) was seen in the AMD patients. No significant difference was seen between the dry and wet AMD. On multivariate logistic regression analysis, the lower age, absence of AMD, and male gender were associated with a higher risk of PDR.

Conclusion:

The presence of AMD was noted to statistically reduce the risk of DR. Our results may be useful in the field of resource allocation and awareness of DR.

Evaluation of the effect of smokeless tobacco (Maras powder) on choroidal and retinal blood flow: an optical coherence tomography angiography study

ABSRTACT

PURPOSE: To investigate the acute and chronic effects of the use of smokeless tobacco (Maras powder) on macular and choroidal blood flow, via optical coherence tomography angiography (OCTA).

METHODS

The study included 30 eyes of 30 patients using smokeless tobacco (ST) as the study group and 30 eyes of 30 healthy individuals as the control group. All subjects underwent a full ophthalmological examination, and baseline OCTA measurements were taken. Flow area in superficial capillary plexus (SCP), in deep capillary plexus (DCP), in choriocapillaris (mm²⁾ and mean vascular density (VD) and foveal avascular zone in SCP and in DCP were assessed. Subfoveal choroidal thickness (SFCT) and central macular thickness were measured as well.

RESULTS

The SFCT measurements were determined to be significantly low in the study group (p < 0.001). In the comparison of the study group measurements at 5 m, 30 m and 1 h after using ST compared to the baseline measurements, SCP and DCP flow area, VD, CC flow area and SFCT were determined to have significantly decreased, statistically (p < 0.001).

CONCLUSION

OCTA could be important in showing that choroidal microvascular structures have been affected before occurence of the apparent clinical signs associated with acute and chronic ST use.

Prevalence of polypoidal choroidal vasculopathy in Indian population: Risk factors, clinical and imaging characteristics

Aim

To assess prevalence, clinical presentation and multimodal imaging characteristics of polypoidal choroidal vasculopathy (PCV) in a hospital-based setting in South India.

Methods

Electronic medical records (EMR) of new patients presenting with suspected clinical signs of wet age-related macular degeneration (AMD) in a tertiary hospital from January to December 2016 were retrospectively analyzed using keywords and filtered for patient who underwent multimodal imaging. Clinical presentations were categorized into predominantly hemorrhagic, exudative or mixed pattern. The imaging features were compared in these clinical groups. The multimodal images were graded by two masked graders and discrepancies between them were settled by a senior arbitrator.

Results

Of the 147 clinically suspicious cases of PCV out of 785 patients with clinical presentation of AMD as recorded in the EMR, 73 (49.7%) patients had a multimodal imaging diagnosis of PCV. There was no difference in the demography, distribution of polyps, ICGA and OCT characteristics in eyes presenting with hemorrhagic, exudative or mixed clinical features.

Conclusion

Approximately half of South Asian patients presenting with clinical features of neovascular AMD harbor PCV irrespective of their clinical presentation and so we recommend that multimodal imaging is done in all cases of suspicious neovascular AMD in Indian population.

A Population-based Study on the Prevalence and Associated Factors of Age-related Macular Degeneration in Northern Iran the Gilan Eye Study

Purpose: To estimate the prevalence and associated factors of AMD in an Iranian population in 2014.Methods: In this population-based cross-sectional study, a total of 2975 Iranian residents (age: ≥50 years) from the urban and rural areas of Gilan province were included. The prevalence of different grades of AMD was determined using the International Age-Related Maculopathy Epidemiological Study Group grading system.Results: Of 2975 eligible individuals, 2587 (87.0%) subjects participated and 2275 (76.5%) subjects (62.6 ± 8.8 years old) had gradable fundus photographs. Age- and sex-standardized prevalence of early and late AMD based on the 2016 Iran census were 13.2% (95% confidence interval [CI], 10.6-16.2) and 0.7% (95% CI, 0.4-1.3), respectively. In multivariate analysis, each decade increase in age was associated with the adjusted odds of any (adjusted odds ratio [AOR] = 1.31, 95% CI, 1.09-1.56; P = .0031), early (AOR = 1.27, 95% CI, 1.06-1.53; P = .012) and late AMD (AOR = 2.39, 95% CI, 1.08-5.28; P = .031). Hyperopia was identified to be less frequent in late AMD (AOR = 0.20, 95% CI, 0.04-0.80; P = .024). No significant association was found between AMD and sex, smoking, outdoor working, diabetes, hypertension, pseudophakia, hyperlipidemia and myopia.Conclusion: Gilan Eye Study demonstrated the first estimate of age-specific AMD prevalence in Iran being compatible with other WHO regions. With the expected increase in the life expectancy and aging of Iranians, the number of people affected by AMD will be increasing in future. Healthcare policy makers should be advised to provide more efficient eye care services and preventive strategies in this regard.

Prevalence of and factors related with abnormal fundoscopic findings among the elderly population in a rural community in South Korea

We aimed to report the results of fundus photography ophthalmic examinations among older adults in a rural community in South Korea. We used data from the Korean Social Life, Health, and Aging Project cohort study, which was designed to examine the entire population of individuals aged 60 years or older and their spouses living in a rural Village K of Ganghwa Island, South Korea. At baseline, a total of 860 people was targeted as the study population. From December 2011 to January 2019, five health examinations were conducted, including baseline and follow-up tests. During the fifth wave of the study, we performed fundus photography to assess eye health. Ophthalmic and physical examinations were conducted for 387 people who participated in the fifth wave by trained researchers. Systemic factors were evaluated via blood and diagnostic tests. After excluding eight people who did not undergo follow-up fundoscopy, a total of 379 participants was included for analysis. We classified the participants into two groups with either no (zero) or one or more suspicious ophthalmic diseases. The abnormalities included media opacity, suspected glaucoma, and suspicion of retinal disease as diagnosed by a trained specialist. We further categorized ophthalmic conditions as clinically insignificant, follow-up needed, semi-urgent, and urgent conditions. We included 379 participants, of which 225 (59.4%) were women. The mean age of the participants was 76.4 ± 6.2 years. Among all participants, 81% (n=307) had one or more abnormalities on fundus screening. Older age, living alone, high blood pressure, and high fasting insulin were associated with an increased risk of having ≥ one eye disease. In terms of triage, 3.7% (n= 14) of the observed conditions were urgent, and 25.9% (n= 98) were semi-urgent. Therefore, we documented fundoscopy results among the elderly population in a rural community in South Korea. Elderly people living alone were more likely to have eye disease. Policies to improve eye health are needed to prevent vision loss in this population.

The prevalence and risk factors for cataract in rural and urban India

Purpose:

To report the prevalence and risk factors of cataract and its subtypes in older age group.

Methods:

A total of 6617 subjects were recruited from both rural and urban areas. A detailed history including data on demographic, socioeconomic and ocular history was obtained. Lens opacity was graded according to the Lens Opacity Classification System III (LOCS III).

Results:

Cataract was present in 1094 of the rural and 649 subjects in the urban population. Monotype subtype cataracts were found in 32% and 25% in rural and urban population and 12.68% and 18.6% were mixed cataracts in the rural and urban groups. In baseline characteristics history of diabetes, alcohol intake and presence of age-related macular degeneration were the risk factors in urban group. On multivariate analysis, the only significant risk factors for any cataract in subjects ≥60 years were increasing age in both rural [odds ratio (OR), 1.07] and urban (OR, 1.08) population, and HbA1c (OR, 1.14) in rural population. Overweight (OR, 0.6) was found to be a protective factor, and lower social economic status (OR, 1.52) a risk factor for cataract in urban population. A significant urban–rural difference was found in the prevalence of cataract and its subtypes (P ≤ 0.05).

Conclusion:

We found the risk factors for any cataract in older age group to be increasing age and HbA1c in rural group. Age and lower social economic status were found to be the risk factors in urban arm. A statistically significant difference was found on comparison of the prevalence of cataract and its subtypes between the rural and urban population.

A Multinational Comparison of Anti-Vascular Endothelial Growth Factor Use: The United States, the United Kingdom, and Asia-Pacific

PURPOSE

A comparison of anti-vascular endothelial growth factor (anti-VEGF) medication use across multiple countries.

CLINICAL RELEVANCE

Anti-VEGF medication use is now considered first-line treatment for numerous retinal diseases globally. Exploring medication choices, costs within each healthcare system, policy challenges, emerging treatments, and patient access all provide insight into a newly recognized and major public health issue.

METHODS

All data presented in this review are available through the published English literature in PubMed, non-peer-reviewed trade publications, and reported surveys. The following search terms were used: anti-VEGF OR bevacizumab OR ranibizumab OR aflibercept OR pegaptanib OR conbercept AND trends OR survey OR cost OR patterns OR preference. Countries with large populations and available data included the United States, United Kingdom, China, India, Korea, Singapore, and Australia. Population and economic statistics were obtained from published reports from the World Bank, World Health Organization, and Commonwealth Fund.

RESULTS

Anti-VEGF medication use and costs are significant aspects of patient and healthcare system expenditures in each nation and may have an especially large potential economic burden in India and China. Bevacizumab use comprises the majority of anti-VEGF medication use in the United States and Singapore, although aflibercept use is growing rapidly. Paradoxically, data demonstrate that there is a significant trend in medication choice toward ranibizumab and aflibercept among practice settings outside of the United States, such as the United Kingdom, China, South Korea, and Australia. The price of anti-VEGF medications ranged from US $30 (ziv-aflibercept) to US $1950 (ranibizumab and aflibercept). Ranibizumab's price ranged from US $240 in India to US $1950 in the United States. Conbercept in China costs approximately US $1150 per dose.

CONCLUSIONS

Outside of the United States, many nations are using a majority of more expensive anti-VEGF medications, which may lead to increased costs and decreased access. Increasing the availability of safely compounded anti-VEGF medications will likely improve access, create patient/provider choice, and decrease relative healthcare costs for the growing burden of retinal diseases globally.

Association of obesity and age-related macular degeneration in Indian population

Purpose:

The aim of this study was to establish the prevalence and association of age-related macular degeneration (AMD) and obesity which was not studied extensively in Indian population over 60 years of age.

Methods:

This was a cross-sectional, population-based study. A total of 4791 patients with gradable fundus photography were included. All patients underwent detailed ophthalmic examination and AMD was graded with retinal photographs. Grading of AMD was done according to the International ARM Epidemiological Study Group and staged based on grading in worse eye. The association of AMD severity and obesity (based on body mass index, waist–hip ratio, waist circumference, isolated abdominal obesity, isolated generalized obesity, and combined obesity) was assessed. The main outcome variable was an association between the presence and severity of AMD with different grades of obesity.

Results:

No direct significant association was noted between the presence and severity of AMD and any obesity indices. Subgroup analyses based on lifestyle patterns and common systemic pathologies in AMD population were done. Late AMD was significantly associated with tobacco consumption in population with combined obesity (P = 0.033 and odds ratio = 2.998).

Conclusion:

No direct association was noted between the presence or severity of AMD and obesity in South Indian population. However, indirect associations between the severity of AMD and combined obesity were found.

Prevalence and causes of low vision and blindness in an elderly population in Nepal: the Bhaktapur retina study

BACKGROUND

This study aims to explore the prevalence and causes of low vision and blindness focused on retinal disease in a population above 60 years in Nepal.

METHODS

Two thousand one hundred subjects were enrolled in a population-based cross-sectional study. History, presenting and best corrected visual acuity after subjective refraction, anterior and posterior segment examinations was obtained in detail.

RESULTS

Among the total subjects, 1860 (88.57%) had complete information. Age varies from 60 to 95 (mean age: 69.64 ± 7.31) years. Low vision and blindness in both eyes at presentation was found in 984 (52.90%, 95% confidence interval (CI): 50.60-55.19) and 36 (1.94%, 95% CI: 1.35-2.66) subjects respectively. After best correction, bilateral low vision and blindness was found in 426 (22.92%, 95% CI: 21.01-24.88), and 30 (1.61%, 95% CI: 0.10-2.30) subjects respectively. As compared to 60-69 years old, risk of visual impairment was four times higher (95% CI:3.26-5.58) in the 70-79 year olds and 14 times higher (95% CI: 9.72-19.73) in the age group 80 years and above. Major causes of bilateral low vision were cataract (68.07%), followed by retinal disorders (28.64%), and for blindness; retinal disorders (46.66%), followed by cataract (43.33%). Illiteracy was significantly associated with visual impairment.

CONCLUSION

Among the elderly population, prevalence of visual impairment was high. Refractive error, cataract and retinal disorders were the major cause of low vision. Screening the population at the age 60 years and above, focused on cataract and posterior segment diseases, providing glasses and timely referral can help reduce visual impairment.

Prevalence and factors associated with age-related macular degeneration in a southwestern island population of Japan: the Kumejima Study

AIMS

To evaluate the prevalence of and factors associated with age-related macular degeneration (AMD) in a rural population of southwestern Japan.

METHODS

This population-based cross-sectional study of all residents aged 40 years or older was conducted on the island of Kumejima, Okinawa, Japan. Of 4632 eligible residents, 3762 completed a comprehensive questionnaire and underwent ocular examination (participant rate, 81.2%). A non-mydriatic fundus photograph was used to grade AMD lesions according to the Wisconsin protocol. Prevalence of AMD was calculated and factors associated with AMD were identified by logistic regression.

RESULTS

Of 3068 subjects with gradable photographs, 469 had early AMD and 4 had late AMD. Age-adjusted prevalence was 13.4% for any AMD, 13.3% for early AMD and 0.09% for late AMD. In multivariate analysis, any AMD was positively associated with age (OR 1.04 per year, 95% CI 1.03 to 1.05), male sex (OR 1.42, 95% CI 1.14 to 1.75) and history of cataract surgery (OR 1.35, 95% CI 1.00 to 1.82) and was negatively associated with longer axial length (OR 0.85 per millimetre, 95% CI 0.74 to 0.96). Early AMD similarly showed significant associations with these same factors.

CONCLUSIONS

Prevalence of early or late AMD in a southwestern island population of Japan was 13.4% or 0.09%. Our data suggest relatively high prevalence for early AMD and low prevalence for late AMD in this sample of rural Japanese population. Significant factors associated with any or early AMD were mostly similar to that of previous studies.

Multiple deprivation, vision loss, and ophthalmic disease in adults: global perspectives

The association between socioeconomic position and morbidity and mortality has long been recognized. We evaluate the evidence for an association between multiple aspects of deprivation and ocular health in a global context. This is a systematic review of studies that evaluated deprivation in the adult population in the context of the major acquired causes of visual loss such as cataract, diabetic eye disease, glaucoma, age-related macular degeneration, and ocular trauma. The search strategy identified relevant studies reported between 1946 and August 2016, with randomized control trials, case-control, cohort, and cross-sectional study designs being selected for inclusion. The studies identified in this review from across the world demonstrate the extent to which the common themes such as low educational attainment and low income may be associated with increased incidence of various sight-threatening conditions and may adversely affect access to specialist assessment and delivery of treatment. Health inequality may always persist, but an increased recognition of the importance of the various impacts of deprivation may empower policy makers to target limited resources to the most vulnerable groups in order to deliver the greatest benefit.

Prevention of Age-Related Macular Degeneration

Age-related macular degeneration (AMD) compromises quality of life. However, the available therapeutic options are limited. This has led to the identification of modifiable risk factors to prevent the development or alter the natural course and prognosis of AMD. The identification and modification of risk factors has the potential for greater public health impact on reducing morbidity from AMD. Likewise, identifying the imaging clues and genetic clues could serve as a guide to recognizing the propensity for progression to severe and end stages of the disease. Several attempts, both successful and unsuccessful, have been made for interventions that could delay the progression of AMD. Of these, pharmacological interventions have shown promising results. The Age-Related Eye Disease Study 1 and 2 have shown the beneficial role of antioxidants in a selected group of patients.

Prevalence and the risk factors for visual impairment in age-related macular degeneration

PurposeTo characterize the type, and the causes of visual impairment (VI) in various stages of early and late age-related macular degeneration (AMD) and the factors associated with visual impairment in subjects with AMDMethods6617 subjects ≥60 years were enumerated; 5495 (83.04%) participated in eye examination. Of which, 4791 subjects had gradable fundus images. AMD was graded per International ARM Epidemiological Study Group. Subjects underwent detailed ophthalmic exam. VI was defined per the WHO classification. Mild VI was defined as VA less than 6/12 to 6/18, moderate VI-VA less than 6/18 but up to 6/60, severe VI-VA less than 6/60 but up to 3/60 and legal blindness-VA worse than 3/60. Factors associated with VI in AMD was analyzed with univariate and logistic regression analysis.ResultsNine hundred and eighty-eight subjects were identified as having AMD (893 with early AMD and 95 with late AMD); 85% of the subjects (95% CI: 82.7-87.1) had no VI, 13.1% had mild VI (95% CI: 11.1-15.3), 0.8% had severe VI (95% CI: 0.4-1.6), 1.1% had legal blindness (95% CI: 0.6-1.9). Prevalence of any VI was 13.7% in early AMD and 27.4% in late AMD, P=0.0004; age group 65-70 years (OR=1.89, 95% CI: 1.16-3.08, P=0.011), and those ≥75 years (OR=3.67, 95% CI: 1.95-6.91, P=0.0001) had greater odds of VI compared with age group 60-64 years. Male gender was a protective factor for VI (OR=0.57, CI: 0.36-0.90, P=0.016). Cataract (31.8%) and refractive error (28.4%) accounted for a majority of the VI.ConclusionsCataract and refractive error account for a significant proportion of VI in the south Indian population with AMD. Early AMD is the third leading cause of VI. Greater age and female gender are associated with VI in subjects with AMD.

Prevalence of and risk factors for age-related macular degeneration in Nepal: the Bhaktapur Retina Study

Aim

This study aimed to explore the prevalence of and risk factors for age-related macular degeneration (AMD) in an elderly population in Nepal.

Subjects and methods

This is a population-based, cross-sectional study. A sample size of 2,100 was calculated. A total of 1,860 (88.6%) subjects aged >60 years were enrolled for the study from 30 clusters in the district. Detailed history, visual acuity, and anterior segment and posterior segment examinations were performed. AMD was graded according to the International ARM Epidemiological Study Group.

Results

Among the total study population, 659 subjects had any AMD (35.43%; 95% confidence interval [CI]: 33.25–37.65), 484 had mild dry AMD (26.02%; 95% CI: 24.04–28.08), 143 had intermediate dry AMD (7.69%; 95% CI: 6.52–8.99), 19 had geographic atrophy (1.02%; 95% CI: 0.61–1.59), and 13 had wet AMD (0.70%; 95% CI: 0.37–1.19). The overall prevalence of early and late AMD was 33.71% and 1.72%, respectively. Among subjects with dry and wet AMD, 36.53% and 46.1% had visual impairment, while 2.78% and 23.08% were blind, respectively. In multivariate analysis, AMD was significantly higher in subjects with an increased number of cigarettes smoked per day (odds ratio [OR] 1.02, 95% CI: 1.01–1.04; P=0.007) and in subjects with pseudophakia (OR 1.45, 95% CI: 1.12–1.87; P=0.005).

Conclusion

One-third of the population aged ≥60 years have some form of AMD. There was a significant association with the number of cigarettes consumed and with previous cataract surgery.

Age-related macular degeneration in a South Indian population, with and without diabetes

PurposeTo elucidate the prevalence and risk factors of age-related macular degeneration (AMD) in people with diabetes.MethodsOf the 5495 subjects ≥60 years of age recruited in the population-based study in south India, 4791 subjects with gradable images on 30° three-field retinal photographs were analyzed. AMD and diabetic retinopathy (DR) were graded based on the International ARM Epidemiological Study Group classification and International Clinical Diabetic Retinopathy Disease Severity Scale, respectively. All subjects underwent a detailed history, physical examination, and a comprehensive ocular examination.ResultsOf the 4791 subjects, 1256 had diabetes. In those with diabetes, 166 (13.2%) had DR: of which, 9.6% had AMD. Of those with diabetes but no DR, 15.6% had AMD. Presence of DR (OR=0.57, 95% CI: 0.33-0.99, P=0.046) was a protective factor for AMD in diabetes. When adjusted for potential confounding factors, those with AMD and diabetes were from urban areas (OR=1.65, 95% CI: 1.09-2.49, P=0.018), had raised systolic blood pressure (OR=1.02, 95% CI: 1.00-1.03, P=0.01), higher BMI (OR=1.06, 95% CI: 1.02-1.10, P=0.005), and higher serum triglycerides (OR=1.00, 95% CI: 1.00-1.01, P=0.011). A higher level of high-density lipoprotein (HDL) (OR=0.98, 95% CI: 0.96-0.99, P=0.038) was a protective factor for AMD in subjects with diabetes.ConclusionsThe presence of DR and higher serum HDL are protective factors whereas obesity and higher systolic blood pressure are risk factors for AMD in subjects with diabetes.