Prevalence of diabetic retinopathy in an older community. The Blue Mountains Eye Study

Vision loss and diabetic retinopathy prevalence and risk among a cohort of Indigenous and non-Indigenous Australians with type 2 diabetes receiving renal haemodialysis treatment: The retinopathy in people currently on renal dialysis (RiPCORD) study

AIMS

Diabetic nephropathy, vision loss and diabetic retinopathy (DR) are frequent comorbidities among individuals with type 2 diabetes (T2D). The Retinopathy in People Currently On Renal Dialysis (RiPCORD) study sought to examine the epidemiology and risk of vision impairment (VI) and DR among a cohort of Indigenous and non-Indigenous Australians with T2D currently receiving haemodialysis for end-stage renal failure (ESRF).

METHODS

A total of 106 Indigenous and 109 non-Indigenous Australians were recruited in RiPCORD across five haemodialysis centres in urban and remote settings. Clinical assessments, questionnaires and medical record data determined the rates of ocular complications and risk factor profiles.

RESULTS

Prevalence rates include unilateral VI, 23.5 %; bilateral VI, 11.7 %; unilateral blindness, 14.2 %; and bilateral blindness, 3.7 %, with no significant differences between sub-cohorts (p=0.30). DR prevalence rates were 78.0 % among non-Indigenous Australians and 93.1 % among Indigenous Australians (p=<0.001). Non-Indigenous ethnicity (OR: 0.28) and pre-dialysis diastolic blood pressure (OR: 0.84 per 10-mmHg) were protective, while peripheral vascular disease (OR: 2.79) increased DR risk.

CONCLUSIONS

Ocular complications among individuals with T2D and ESRF are disproportionately high, especially for Indigenous Australians, and beyond what can be accounted for by risk factor variation. Findings suggest a need to improve screening and preventative efforts within this high-risk population group.

Eye and adnexa hospitalization in Australia: An ecological study

To investigate the trends of hospital admissions concerning diseases of the eye and adnexa in Australia in the past 2 decades. This is a descriptive ecological study on the population level that examined hospitalization data for the duration between 1998 and 2021 in Australia. Hospitalization data were extracted from the National Hospital Morbidity Database. The chi-squared test was utilized to assess the difference in admission rates between the years 1998 and 2021. Hospital admission rate for diseases of the eye and adnexa increased by 1.20-fold (from 852.32 [95% confidence interval [CI] 848.16-856.47] in 1998 to 1873.72 [95% CI 1868.48-1878.96] in 2021 per 100,000 persons, P < .01). The most common cause of hospitalization for diseases of the eye and adnexa was disorders of the lens (65.7%), followed by disorders of the choroid and retina (15.6%), followed by disorders of the eyelid, lacrimal system, and orbit (7.7%). Hospital admission rate among males increased by 1.25-fold (from 737.67 [95% CI 732.18-743.16] in 1998 to 1657.19 [95% CI 1650.19-1664.20] in 2021 per 100,000 persons). Hospital admission rate among females increased less sharply by 1.03-fold (from 965.37 [95% CI 959.14-971.59] in 1998 to 1964.35 [95% CI 1956.80-1971.90] in 2021 per 100,000 persons). There are clear gender and age roles in the epidemiology of hospital admissions related to eye and adnexa disorders. Lens disorders were the most common cause of hospital admission. The admission rate increase during the past decades could be due to increases in life expectancy, lifestyle changes, and improvements in screening protocols.

Diabetic Retinopathy Screening at the Point of Care (DR SPOC): detecting undiagnosed and vision-threatening retinopathy by integrating portable technologies within existing services

INTRODUCTION

The aim of this study was to determine the prevalence of diabetic retinopathy (DR) in a low socioeconomic region of a high-income country, as well as determine the diagnostic utility of point-of-care screening for high-risk populations in tertiary care settings.

RESEARCH DESIGN AND METHODS

This was a cross-sectional study of patients with diabetes attending foot ulcer or integrated care diabetes clinics at two Western Sydney hospitals (n=273). DR was assessed using portable, two-field, non-mydriatic fundus photography and combined electroretinogram/ pupillometry (ERG). With mydriatic photographs used as the reference standard, sensitivity and specificity of the devices were determined. Prevalence of DR and vision-threatening diabetic retinopathy (VTDR) were reported, with multivariate logistic regression used to identify predictors of DR.

RESULTS

Among 273 patients, 39.6% had any DR, while 15.8% had VTDR, of whom 59.3% and 62.8% were previously undiagnosed, respectively. Non-mydriatic photography demonstrated 20.2% sensitivity and 99.5% specificity for any DR, with a 56.7% screening failure rate. Meanwhile, mydriatic photography produced high-quality images with a 7.6% failure rate. ERG demonstrated 72.5% sensitivity and 70.1% specificity, with a 15.0% failure rate. The RETeval ERG was noted to have an optimal DR cut-off score at 22. Multivariate logistic regression identified an eGFR of ≤29 mL/min/1.73 m2, HbA1c of ≥7.0%, pupil size of <4 mm diameter, diabetes duration of 5-24 years and RETeval score of ≥22 as strong predictors of DR.

CONCLUSION

There is a high prevalence of vision-threatening and undiagnosed DR among patients attending high-risk tertiary clinics in Western Sydney. Point-of-care DR screening using portable, mydriatic photography demonstrates potential as a model of care which is easily accessible, targeted for high-risk populations and substantially enhances DR detection.

Association of blood pressure with incident diabetic microvascular complications among diabetic patients: Longitudinal findings from the UK Biobank

Background

Evidence suggests a correlation of blood pressure (BP) level with presence of diabetic microvascular complications (DMCs), but the effect of BP on DMCs incidence is not well-established. We aimed to explore the associations between BP and DMCs (diabetic retinopathy, diabetic kidney disease, and diabetic neuropathy) risk in participants with diabetes.

Methods

This study included 23 030 participants, free of any DMCs at baseline, from the UK Biobank. We applied multivariable-adjusted Cox regression models to estimate BP-DMCs association and constructed BP genetic risk scores (GRSs) to test their association with DMCs phenotypes. Differences in incidences of DMCs were also compared between the 2017 ACC/AHA and JNC 7 guidelines (traditional criteria) of hypertension.

Results

Compared to systolic blood pressure (SBP)<120 mm Hg, participants with SBP≥160 mm Hg had a hazard ratio (HR) of 1.50 (95% confidence interval (CI) = 1.09, 2.06) for DMCs. Similarly, DMCs risk increased by 9% for every 10 mm Hg of higher SBP at baseline (95% CI = 1.04, 1.13). The highest tercile SBP GRS was associated with 32% higher DMCs risk (95% CI = 1.11, 1.56) compared to the lowest tercile. We found no significant differences in DMCs incidence between JNC 7 and 2017 ACC/AHA guidelines.

Conclusions

Genetic and epidemiological evidence suggests participants with higher SBP had an increased risk of DMCs, but hypertension defined by 2017 ACC/AHA guidelines may not impact DMCs incidence compared with JNC 7 criteria, contributing to the care and prevention of DMCs.

Diabetic Macular Oedema Guidelines: An Australian Perspective

The number of people living with diabetes is expected to rise to 578 million by 2030 and to 700 million by 2045, exacting a severe socioeconomic burden on healthcare systems around the globe. This is also reflected in the increasing numbers of people with ocular complications of diabetes (namely, diabetic macular oedema (DMO) and diabetic retinopathy (DR)). In one study examining the global prevalence of DR, 35% of people with diabetes had some form of DR, 7% had PDR, 7% had DMO, and 10% were affected by these vision-threatening stages. In many regions of the world (Australia included), DR is one of the top three leading causes of vision loss amongst working age adults (20-74 years). In the management of DMO, the landmark ETDRS study demonstrated that moderate visual loss, defined as doubling of the visual angle, can be reduced by 50% or more by focal/grid laser photocoagulation. However, over the last 20 years, antivascular endothelial growth factor (VEGF) and corticosteroid therapies have emerged as alternative options for the management of DMO and provided patients with choices that have higher chances of improving vision than laser alone. In Australia, since the 2008 NHMRC guidelines, there have been significant developments in both the treatment options and treatment schedules for DMO. This working group was therefore assembled to review and address the current management options available in Australia.

Single-Field Fundus Photography for Screening of Diabetic Retinopathy: The Prevalence and Associated Factors in a Population-Based Study

INTRODUCTION

We aimed to determine the prevalence and risk factors for diabetic retinopathy (DR) in a multi-primary healthcare facilities-based DR screening project by analyzing single-field fundus photographs among patients with diabetes in Rafsanjan City, Iran, based on the Rafsanjan Cohort Study, as a part of the prospective epidemiological research studies in IrAN (PERSIAN).

METHODS

Of all participants in the Rafsanjan Cohort Study (performed in four primary healthcare facilities across Rafsanjan City from August 2015 to December 2017), patients with diabetes were recruited in this study. All participants underwent a standardized interview and clinical and paraclinical examinations for demographic characteristics, and medical conditions according to the PERSIAN's protocols. In addition, digital fovea-centered and single-field fundus photography was performed for DR identification and grading. For assessment of agreement, a subgroup of participants underwent fundus examination, randomly. DR was graded as nonproliferative (NPDR) or proliferative (PDR).

RESULTS

Of 8414 screened participants, 1889 had diabetes. The total prevalence of DR was 6.93% [131 individuals including 110 (5.82%) with NPDR, and 21 (1.11%) with PDR] based on single-field fundus photographs, with almost perfect agreement with fundus examinations (κ = 0.82). On adjusted multivariate analysis, duration of diabetes (OR 1.16, 95% CI 1.13-1.19), positive family history for diabetes (OR 1.73, 95% CI 1.09-2.75), fasting plasma glucose (FPG) ≥ 126 mg/dL (OR 1.98, 95% CI 1.16-3.39), and serum creatinine level (OR 1.79, 95% CI 1.08-2.98) were associated with DR. Factors including age, education level, physical activity, body mass index, hypertension, and cardiovascular and renal diseases did not have association with DR on adjusted multivariate analysis.

CONCLUSIONS

Single-field fundus photography can be used for screening of DR in primary healthcare facilities. In individuals with diabetes, duration of diabetes, positive family history for diabetes, FPG ≥ 126 mg/dL, and serum creatinine level may be associated with DR.

The Prevalence and Risk Factors of Diabetic Retinopathy: Screening and Prophylaxis Project in 6 Provinces of China

PURPOSE

To investigate the prevalence and associated factors of diabetic retinopathy (DR) and advanced DR in Chinese adults with diabetes mellitus (DM).

PATIENTS AND METHODS

A cross-sectional study was performed on 4831 diabetic patients from 24 hospitals from April 2018 to July 2020. Non-mydriatic fundus of patients were interpreted by an artificial intelligence (AI) system. Fundus photos that were unsuitable for AI interpretation were interpreted by two ophthalmologists trained by one expert ophthalmologist at Beijing Tongren Hospital. Medical history, height, weight, body mass index (BMI), glycosylated hemoglobin (HbA1c), blood pressure, and laboratory examinations were recorded.

RESULTS

A total of 4831 DM patients were included in this study. The prevalence of DR and advanced DR in the diabetic population was 31.8% and 6.6%, respectively. In multiple logistic regression analysis, male (odds ratio [OR], 1.39), duration of diabetes (OR, 1.05), HbA1c (OR, 1.11), farmer (OR, 1.39), insulin treatment (OR, 1.61), region (northern, OR, 1.78; rural, OR, 6.96), and presence of other diabetic complications (OR: 2.03) were associated with increased odds of DR. The factors associated with increased odds of advanced DR included poor glycemic control (HbA1c >7.0%) (OR, 2.58), insulin treatment (OR, 1.73), longer duration of diabetes (OR, 3.66), rural region (OR, 4.84), and presence of other diabetic complications (OR, 2.36), but overweight (BMI > 25 kg/m²) (OR, 0.61) was associated with reduced odds of advanced DR.

CONCLUSION

This study shows that the prevalence of DR is very high in Chinese adults with DM, highlighting the necessity of early diabetic retinal screening.

Gene Set Enrichment Analsyes Identify Pathways Involved in Genetic Risk for Diabetic Retinopathy

To identify functionally related genes associated with diabetic retinopathy (DR) risk using gene set enrichment analyses applied to genome-wide association study meta-analyses.

METHODS

We analyzed DR GWAS meta-analyses performed on 3246 Europeans and 2611 African Americans with type 2 diabetes. Gene sets relevant to 5 key DR pathophysiology processes were investigated: tissue injury, vascular events, metabolic events and glial dysregulation, neuronal dysfunction, and inflammation. Keywords relevant to these processes were queried in 4 pathway and ontology databases. Two GSEA methods, Meta-Analysis Gene set Enrichment of variaNT Associations (MAGENTA) and Multi-marker Analysis of GenoMic Annotation (MAGMA), were used. Gene sets were defined to be enriched for gene associations with DR if the P value corrected for multiple testing (Pcorr) was <.05.

RESULTS

Five gene sets were significantly enriched for numerous modest genetic associations with DR in one method (MAGENTA or MAGMA) and also at least nominally significant (uncorrected P < .05) in the other method. These pathways were regulation of the lipid catabolic process (2-fold enrichment, Pcorr = .014); nitric oxide biosynthesis (1.92-fold enrichment, Pcorr = .022); lipid digestion, mobilization, and transport (1.6-fold enrichment, P = .032); apoptosis (1.53-fold enrichment, P = .041); and retinal ganglion cell degeneration (2-fold enrichment, Pcorr = .049). The interferon gamma (IFNG) gene, previously implicated in DR by protein-protein interactions in our GWAS, was among the top ranked genes in the nitric oxide pathway (best variant P = .0001).

CONCLUSIONS

These GSEA indicate that variants in genes involved in oxidative stress, lipid transport and catabolism, and cell degeneration are enriched for genes associated with DR risk. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Does myopia decrease the risk of diabetic retinopathy in both type-1 and type-2 diabetes mellitus?

Purpose

To study the relationship between the severity of myopia and the severity of diabetic retinopathy (DR) in individuals with type 1 or type 2 diabetes mellitus (DM).

Methods

This retrospective study was conducted using data from electronic medical records from a multicentric eyecare network located in various geographic regions of India. Individuals with type 1 or type 2 DM were classified according to their refractive status. Severe nonproliferative DR (NPDR), PDR, or presence of clinically significant macular edema (CSME) with any type of DR was considered as vision-threatening diabetic retinopathy (VTDR).

Results

A total of 472 individuals with type-1 DM (mean age 41 ± 10 years) and 9341 individuals with type-2 DM (52 ± 9 years) were enrolled. Individuals with a hyperopic refractive error had a significant positive association with the diagnosis of VTDR (odds ratio (OR) 1.26; 95%CI 1.04-1.51, P = 0.01) and moderate nonproliferative DR (OR 1.27; 95%CI 1.02-1.59, P = 0.03) in type-2 DM; however, no significant association was found in type-1 DM. After adjusting for age, gender, anisometropia, and duration of diabetes, the presence of high myopia (< - 6 D) reduced the risk of VTDR in type 2 DM (OR 0.18; 95% CI 0.04-0.77, P = 0.02), but no association was found in type 1 DM. Mild and moderate myopia had no significant association with any forms of DR in both type-1 and type-2 DM.

Conclusion

Hyperopic refractive error was found to increase the risk of VTDR in persons with type 2 DM. High-myopic refractive error is protective for VTDR in type 2 DM, but not in type-1 DM.

Global and Regional Prevalence of Diabetic Retinopathy; A Comprehensive Systematic Review and Meta-analysis

PURPOSE

We conducted a systematic search to estimate DR prevalence in different age and gender groups, and to evaluate the determinants of heterogeneity in its prevalence.

METHODS

A systematic and comprehensive search from inception to August 10, 2020, was done in international databases, including Scopus, PubMed, Web of Science, Embase, and other data sources without any restriction to find cross-sectional studies related to the prevalence of DR.

RESULTS

Of 6399 studies, 90 articles with a sample size of 563460 individuals and 204189 diabetic patients were analyzed. The estimated pooled prevalence of DR in the diabetic population in general; in female and in male was 28.41% (95% CI: 25.98 to 30.84); 25.93% (95% CI: 23.54 to 28.31) and 28.95% (95% CI: 26.57 to 31.32); respectively and the prevalence of DR showed no inter-gender difference. The heterogeneity of the pooled prevalence according to I² was 99% (p < .001). According to the meta-regression results, the variables of WHO region (Coefficient of AMRO vs SEARO: 15.56; p: 0.002), age (Coefficient of above 60 years vs below 40 year: 18.67; p: 0.001), type of DR (Coefficient: 19.01; p < .001), and publication year (Coefficient: -0.60; p: 0.001) had a significant correlation with heterogeneity.

CONCLUSION

One third of diabetic patients suffered from DR, mostly NPDR. DR increased markedly after the age of 60 years, which could be due to the longer duration of diabetes. Age, WHO region, type of DR, and publication year affected the heterogeneity in the prevalence of DR.

Investigating the effects of carvacrol in rats using oxygen-induced retinopathy model

Purpose:

Investigating the effects of intraperitoneal carvacrol administration in rats using the oxygen-induced retinopathy (OIR) model.

Methods:

A total of 28 newborn Sprague Dawley rats were used and the OIR model was created using the 50/10% oxygen model. The study composed of four groups in total. While the OIR model was not used in Group I (control group), it was created for Groups II, III, and IV. About 0.01 mL carvacrol, bevacizumab, or 0.9% NaCl was administered intraperitoneal (IP) to the rats in all groups on postnatal day (PND) 14 as follows: Group I and Group II were administered 0.9% NaCl, Group III was administered bevacizumab, and Group IV was administered carvacrol. On PND 18, rats were sacrificed and their right eyes were enucleated.

Results:

Histopathological and immunohistochemical studies showed that the number of vascular endothelial cells (VECs), vascular endothelial growth factor (VEGF), and tumor necrosis factor-α (TNF-α) decreased similarly in Group III and Group IV compared with Group II. VECs values for Group I, Group II, Group III, and Group IV were measured as 0 ± 0, 26.45 ± 4.57, 7.75 ± 1.98, and 5.78 ± 1.72, respectively, and it differed significantly between groups (P < 0.001). Likewise, VEGF levels were observed as 0.06 ± 0.01, 3.31 ± 0.53, 2.47 ± 0.44, and 2.49 ± 0.52, respectively, and it differed significantly between groups (P < 0.001). TNF-α levels were recorded as 0.06 ± 0.01, 3.58 ± 0.38, 2.46 ± 0.49, and 2.29 ± 0.25, respectively, and it differed significantly between groups (P < 0.001). VECs, VEGF, and TNF-α were similar between Group III and IV (range of P values were 0.486–0.998).

Conclusion:

The study demonstrated that carvacrol significantly reduced retinal pathological angiogenesis, NV, VEC nuclei count, VEGF, and TNF-α levels. Moreover, the observed effects were comparable to those of bevacizumab.

Systemic and ocular diseases associated with the development of diabetic macular edema among Japanese patients with diabetes mellitus

Background

Diabetic macular edema (DME) causes severe vision loss among patients with diabetes mellitus (DM). We aimed to investigate systemic and ocular diseases associated with the development of DME in a Japanese population.

Methods

A total of 3.11 million Japanese subjects who were registered in the database of the Japan Medical Data Center from 2005 to 2014 were analyzed. Subjects with DM were defined as individuals who had been prescribed any therapeutic medications for DM, and associated diseases were analyzed. The periods assessed were one year before the development of DME among patients with DME and one year before the last visit to an ophthalmic clinic among patients without DME.

Results

A total of 17,403 patients with DM satisfied the inclusion and exclusion criteria, and 420 patients developed DME. Univariate analysis revealed significant associations between 55 diseases, including 39 systemic and 16 ocular diseases, and DME development. Logistic analysis identified 21 systemic diseases and 10 ocular diseases as significant factors associated with DME development.

Conclusion

Various types of systemic and ocular diseases are associated with DME development. Subjects with DM who present these risk factors must be carefully monitored to prevent visual impairment.

Effect of postprandial hyperglycemia at clinic visits on the incidence of retinopathy in patients with type 2 diabetes: An analysis using real-world long-term follow-up data

AIMS/INTRODUCTION

There is little evidence on the role of postprandial glycemia in the incidence of diabetic retinopathy (DR) in a real-world setting. We aimed to assess the effect of postprandial hyperglycemia at clinic visits on the incidence of DR in patients with type 2 diabetes, and whether its effect differs depending on glycated hemoglobin (HbA1c) values and age.

MATERIALS AND METHODS

Intrapersonal mean blood glucose levels at 1-2 h post-breakfast (1-2h-PBBG), post-lunch (1-2 h-PLBG) and both (1-2h-PBLBG) during 2 years from the first visit were used as baseline data. This retrospective cohort study enrolled 487, 323 and 406 patients who had 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG measurements, respectively. These three groups were followed from 1999 up through 2017.

RESULTS

DR occurred in 145, 92 and 126 patients in the 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG groups, respectively. Multivariate Cox regression analysis showed that the mean 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG levels were significant predictors of DR, independent of mean HbA1c. In patients with mean HbA1c <7.0% and those with a baseline age <60 years, the mean 1-2h-PBLBG, 1-2h-PBBG and 1-2h-PLBG levels were significant predictors.

CONCLUSIONS

Postprandial hyperglycemia at clinic visits might predict the incidence of DR, independent of HbA1c. The effect of postprandial hyperglycemia on DR is obvious in patients with well-controlled HbA1c and in younger patients. Even with the lower HbA1c level, correcting postprandial hyperglycemia is important for preventing DR, especially in middle-aged adults with type 2 diabetes.

Epidemiology of Diabetic Retinopathy at Eye Clinic Svjetlost Sarajevo: Two Years Retrospective Single Center Study

Introduction:

Diabetic retinopathy (DR) is an important cause of blindness, and occurs as a result of long-term accumulated damage to the small blood vessels in the retina. 2.6% of global blindness can be attributed to diabetes. Disease severity was most often classified by the Early Treatment Diabetic Retinopathy Study (ETDRS) classification for DR severity. Patients are usually categorized based on the severity of DR as having mild nonproliferative diabetic retinopathy (NPDR), moderate NPDR, severe NPDR, or proliferative diabetic retinopathy (PDR).

Aim:

To evaluate DR status among patients at Eye Clinic Svjetlost Sarajevo , both, type 1 and type 2 DM patients who presented in our clinic at 2 years period – from June 2016 to June 2018. This is single center study.

Methods:

Retrospective analysis of 753 diabetic patients that came for the first check up in our institution during those two years, 363 patients were male and 390 were female. Patients were divided in 3 groups (based on DR changes): a) No changes, b) Nonproliferative DR (with and without Diabetic macular edema–DME), c) Prolipherative DR (with and without DME + Advanced PDR).

Results:

There were 35% of patients with no ocular changes, 41.2% had NPDR and 24% had PDR. Prevalence of DR in our study was 65.32%. Distribution of NPDR was 66.27%, and PDR was 33.73%. DME was present in 33.70% cases. In NPDR, DME was presented in 51% of the cases, while in PDR was presented in 49% of the cases. In state of advanced PDR, PDR was presented in 30.52% cases, tractional detachment and haemophtalmus in 50.20% of cases and neovascular glaucoma in 19.28%. Sixty-three patients ended up with vitroretinal surgery (8.4%) while in other studies that number is up to 3%. Out of that number 9 patients were patient with virgin eyes (14.28%). Neovascular glaucoma occurred in 19.28% of diabetics with proliferative retinopathy and 4.60% in all of diabetics.

Conclusion:

Diabetic retinopathy status of patients presenting at Eye clinic Svjetlost Sarajevo, Bosnia and Herzegovina is quite poor. There is a big need for early DR screening measures, good prevention and management of DR risk factors. Adequate and ON TIME management of DM and its vision threatening complications is of major importance.

Is central obesity associated with diabetic retinopathy in Chinese individuals? An exploratory study

Objective

To our knowledge, the independent association between central obesity, defined by waist circumference (WC) or waist-to-hip ratio (WHR), and diabetic retinopathy (DR) remains unknown in Chinese individuals.

Method

The study was conducted in two stages. First, the relationship between WC or WHR and DR was estimated in a case-control set (DR vs. non-DR) for the whole population before and after propensity score matching. Subsequently, a systematic review and meta-analysis was performed on evidence from the literature to validate the relationship.

Results

Of 511 eligible patients, DR (N = 156) and non-DR (N = 156) patients with similar propensity scores were included in the propensity score matching analyses. Central obesity (defined by WC) was associated with risk of DR (odds ratio [OR] 1.07, 95% confidence interval [95% CI] (1.03–1.10). The meta-analysis showed that central obesity significantly increased the risk of DR by 12% (OR 1.12, 95% CI 1.02–1.22). Analysis of data from 18 studies showed a significant association between continuous body mass index and risk of proliferative DR (OR 0.95, 95% CI 0.93–0.98; I² = 50%).

Conclusion

Central obesity, particularly as defined by WC, is associated with the risk of DR in the Chinese population.

Prevalence of and Risk Factors for Diabetic Retinopathy in a Rural Chinese Population: The Yangxi Eye Study

Purpose

To investigate the prevalence and determinants of diabetic retinopathy (DR) among older adults in rural Southern China.

Methods

Using random cluster sampling, persons aged 50 years or older were randomly selected in rural Yangxi County, Guangdong Province, China. All participants underwent a standardized interview, fundus photography, and point of service glycosylated hemoglobin A1c (HbA1c) testing. Diabetes mellitus (DM) was diagnosed based on confirmed medical history or HbA1c ≥6.5%. Fundus photographs were graded for DR and diabetic macular edema (DME) based on the United Kingdom National Diabetic Eye Screening Program guidelines. Prevalence of and risk factors for DR and vision-threatening diabetic retinopathy (VTDR) were evaluated.

Results

Among 5825 subjects who participated (90.7% response rate) in the Yangxi Eye Study, 562 (9.6%) were diagnosed with DM, including 79 (14.1%) known and 483 new (85.9%) cases. Among DM cases, 476 (84.7%) had gradable fundus photos. The prevalence of any DR and VTDR were 8.19% (95% confidence interval [CI] 5.9-11.0) and 5.25% (95% CI 3.43-7.66), respectively. These figures were 23.9% and 12.7% for known and 5.43% and 3.95% for new DM cases. Risk factors for any DR were higher HbA1c level (OR [odds ratio] per unit 1.34, P < 0.001), longer duration of DM (OR per year = 2.29, P < 0.001) and having previously undergone cataract surgery (OR 4.11, P < 0.030).

Conclusions

Our study found a lower prevalence of DR among adults 50 years and older than in previously reports. Perhaps this difference can be explained by the short duration of most cases.

Multiethnic Genome-Wide Association Study of Diabetic Retinopathy Using Liability Threshold Modeling of Duration of Diabetes and Glycemic Control

To identify genetic variants associated with diabetic retinopathy (DR), we performed a large multiethnic genome-wide association study. Discovery included eight European cohorts (n = 3,246) and seven African American cohorts (n = 2,611). We meta-analyzed across cohorts using inverse-variance weighting, with and without liability threshold modeling of glycemic control and duration of diabetes. Variants with a P value <1 × 10-5 were investigated in replication cohorts that included 18,545 European, 16,453 Asian, and 2,710 Hispanic subjects. After correction for multiple testing, the C allele of rs142293996 in an intron of nuclear VCP-like (NVL) was associated with DR in European discovery cohorts (P = 2.1 × 10-9), but did not reach genome-wide significance after meta-analysis with replication cohorts. We applied the Disease Association Protein-Protein Link Evaluator (DAPPLE) to our discovery results to test for evidence of risk being spread across underlying molecular pathways. One protein-protein interaction network built from genes in regions associated with proliferative DR was found to have significant connectivity (P = 0.0009) and corroborated with gene set enrichment analyses. These findings suggest that genetic variation in NVL, as well as variation within a protein-protein interaction network that includes genes implicated in inflammation, may influence risk for DR.

Diabetic retinopathy in type 1 diabetes patients in Western Norway

PURPOSE

To describe the prevalence of diabetic retinopathy (DR), associated risk factors and health-related quality of life (HRQoL) in a population-based cohort of patients with type 1 diabetes mellitus (DM1).

METHODS

All patients underwent a general and ophthalmic examination including seven-field stereo fundus photography for grading of DR and diabetic macular oedema (DMO). Kaplan-Meier survival analyses were performed to evaluate disease progression in relation to diabetes duration, age and year of diabetes onset. HRQoL and its association with DR were assessed by the Medical Outcomes Study Short Form 36 (SF-36) questionnaire.

RESULTS

A total of 237 DM1 patients were included. Mean age at inclusion was 34 years (range, 4-75 years), and mean diabetes duration was 19 years (range, 5 months-63 years). A total of 145 patients (61%) had DR. Sixty-two patients (26%) had mild, 39 (16%) moderate and 13 (5%) severe nonproliferative DR, while 31 (13%) had proliferative DR. The prevalence of DMO was 8%. The most important risk factors predicting severity of DR were diabetes duration (p < 0.0001) and HbA1c level (p < 0.0001). Neuropathy (p = 0.006), nephropathy (p = 0.004) and male gender (p = 0.02) were also significant predictors of DR. Compared to normative SF-36 data, there was a linear trend of decreasing HRQoL with increasing severity of DR that was statistically significant for the four physical dimension scores.

CONCLUSION

The prevalence of DR in DM1 was largely within the range of previous reports. Diabetes duration, HbA1c level, neuropathy, nephropathy and male gender were all significant predictors of DR severity. The patients with more severe DR had lower HRQoL.

Prevalence and risk factors of diabetic retinopathy among an elderly population with diabetes in Nepal: the Bhaktapur Retina Study

Aim

Diabetic retinopathy (DR) is an emerging cause of blindness in developing countries. This study aimed to explore the prevalence and risk factors of DR in an elderly population in Nepal.

Subjects and methods

This is a population-based, cross-sectional study. A total of 1860 subjects at the age 60 years and above participated (response rate 88.6%). A detailed history was obtained, presenting and best-corrected visual acuity were measured, and anterior segment and posterior segment examinations were carried out. Blood pressure and random blood sugar were recorded; body mass index was calculated, and abdominal girth was measured. DR was graded by clinical examination using Early Treatment Diabetic Retinopathy Study criteria.

Results

Diabetes was found in 168 (9%) subjects (mean age 69.6 years), 31 (18.5%) of whom were newly diagnosed. The prevalence of DR was 23.8% (95% confidence interval [CI]: 17.7%–31%) among the persons with diabetes. The prevalence of DR among newly diagnosed subjects with diabetes was 6.5% (95% CI: 0.8%–21.4%). The prevalence of vision-threatening DR was 9.5% (95% CI: 5.5%–15%) and was higher in males. The prevalence of DR was 83.3% (95% CI: 35.9%–99.6%) among those with diabetes for over 20 years. In multivariable logistic regression analysis, duration of diabetes, hypertension, and alcohol consumption were significantly associated with DR.

Conclusion

DR is a common problem among the elderly population with diabetes in Nepal. The duration of diabetes, hypertension, and alcohol consumption are the risk factors for the development of DR. Strategies have to be developed for timely diagnosis of diabetes and screening for DR.

Factors Associated with Prevalent Diabetic Retinopathy in Chinese Americans: The Chinese American Eye Study

OBJECTIVE

To identify factors associated with prevalent diabetic retinopathy (DR) among Chinese American adults with type 2 diabetes mellitus (T2DM), and to compare these factors to ones previously described for a population-based sample of Latinos with a higher DR prevalence.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

4582 Chinese Americans aged 50 or older residing in Monterey Park, California.

METHODS

Participants completed an in-home questionnaire on socio-demographic status and medical history, and a comprehensive clinical eye examination, using the same protocol implemented in the Los Angeles Latino Eye Study. Fundus photographs from 7 Early Treatment Diabetic Retinopathy fields were graded in a masked manner using a modified Airlie House grading system to assess presence and severity of DR. Logistic regression analyses based on a conceptual model of DR risk identified factors associated with prevalent DR.

MAIN OUTCOME MEASURES

Odds ratios (ORs) and 95% confidence intervals (CIs) for factors associated with DR and vision-threatening DR (VTDR).

RESULTS

In total, 238 participants were diagnosed with any DR; 27 of these were classified as having VTDR. Both, any DR and VTDR showed statistically significant positive associations with T2DM duration (OR5-9 years = 1.24, OR10-14 years = 2.07, OR15+years = 3.99), glycosylated hemoglobin (HbA1c) (OR6.5-6.9% = 1.33, OR7-7.9% = 1.86, OR8%+ = 3.22), systolic blood pressure (SBP) (ORper 10mmHg+ = 1.19), and insulin treatment (ORinsulin+ = 2.44). For VTDR, we also found novel associations with antihypertensive drugs (OR: 0.18; 95% CI: 0.06-0.61) and statins (OR: 4.96; 95% CI: 1.60-16.41). Chinese Americans and Latinos had a nearly identical DR probability based on HbA1c and SBP. However, Latinos had a higher DR probability at every year of duration of T2DM (≥ 5 years).

CONCLUSIONS

While we observed an overall lower DR prevalence in Chinese Americans than in Latinos (35.8% of individuals with TD2M in Chinese Americans versus 42.0% in Latinos), our data indicate that the impact of increasing HbA1c and SBP on DR probability is incrementally the same in both populations. However, increasing T2DM duration is associated with higher DR probability in Latinos than Chinese Americans, even after controlling for other known predictors. Novel factors associated with VTDR include antihypertensive drugs and statins. However, to determine if these drugs impact VTDR susceptibility, we need longitudinal data and more cases.

Prevalence of Diabetic Retinopathy among Subjects with Known Diabetes in China: The Beijing Eye Study

Purpose

To evaluate the prevalence of diabetic retinopathy and risk factors among patients with self-reported diabetes mellitus in China.

Methods

The Beijing Eye Study, a population-based study on inhabitants aged 40+ years, included 4439 subjects. Fundus photographs of the worse eye from participants with self-reported diabetes were graded.

Results

Fundus photographs ready for evaluation and a filled out questionnaire were available for 4127 (93.0%) subjects. The prevalence of self-reported diabetes was 235/4127 (5.7%). Among the subjects with a self-reported diagnosis of diabetes, diabetic retinopathy was detected on the fundus photographs of 86 (37.1%) subjects, with macular edema in 12 (5.2%) subjects, clinically significant macular edema in 6 (2.6%) subjects, and a vision-threatening stage of the retinopathy in 12 (5.2%) subjects. Diabetic retinopathy was associated with rural region (p=0.004), longer duration of diabetes (p=0.009), use of diabetic medications (p=0.02), and lower education background (p=0.003).

Conclusions

Prevalence of diabetic retinopathy among Chinese patients aged 40+ years with a self-reported diagnosis of diabetes is about 37%, with a vision-threatening stage of the retinopathy detected in 5% of the subjects. About 5.7% of the adult Chinese population report on a known diagnosis of diabetes mellitus, with about 15% of these subjects knowing about the presence of diabetic retinopathy. The frequency of known diabetes mellitus is lower in rural regions than in urban regions, while diabetic retinopathy overall and macular edema among the subjects with known diabetes mellitus were significantly more common in the rural group.

The Prevalence of Blindness and Low Vision in Older Onset Diabetes Mellitus and Associated Factors: A Community-Based Study

PURPOSE

This community-based study was conducted to assess the prevalence and related factors of low vision and legal blindness in older onset diabetic patients (diagnosed at age 30 and older).

METHODS

All known diabetic patients who live in the four primary health care center region Abidinpaşa Ankara, Turkey (total population: 96,348) were included in this cross-sectional study. The prevalence of known diabetes mellitus is 2.2%, of which 96.6% are older onset and 3.4% are younger onset.

RESULTS

In the older onset diabetes group (1289 cases), 10.8% of the population had low vision and only 2.7% had legal blindness. Diabetic retinopathy (DR) was observed in 23.6% of the patients with low vision (42% proliferative DR) and in 62.9% of the patients with legal blindness (90.1 % proliferative DR).

CONCLUSIONS

In older onset diabetic patients with low vision, nonproliferative retinopathy was a more frequent cause of impaired vision than proliferative retinopathy. Low vision and legal blindness caused by retinopathy were significantly associated with sex, age at examination, age at diagnosis, duration of diabetes, type of diabetes treatment, and hypertension in univariate analysis. However, in logistic regression analysis, low vision and legal blindness caused by retinopathy were found to be associated with longer duration of diabetes (> or =15 years), use of insulin, and hypertension.

The Beijing Desheng Diabetic Eye Study: rationale, design, methodology and baseline data

AIM

To present the rationale, design, methodology, and the baseline data of the Beijing Desheng Diabetic Eye Study (BDDES), and to determine the prevalence of diabetic retinopathy (DR) and possible risk factors in patients with type 2 diabetes mellitus (T2DM) in an urban community of Beijing, China.

METHODS

Community-based prospective cohort study of persons diagnosed with T2DM aged 30y or older. The main variables of interest are the presence and progression of DR as determined by the standardized ETDRS grading of seven fields fundus photographs. The presence and severity of DR were analyzed for possible correlations to non-genetic and genetic dispositions.

RESULTS

A total of 1438 participants with data available for analysis, the prevalence of any DR was 35.4%. The prevalence of mild non-proliferative diabetic retinopathy (NPDR), moderate NPDR, severe NPDR, and proliferative diabetic retinopathy was 27.7%, 2.6%, 0.5% and 4.5%, respectively. By multiple logistic regression analysis, risk factors for the presence of any DR included male (P=0.031), lower income level (P=0.011), lower education background (P=0.022), longer duration of diabetes (P=0.001), younger age at diabetic onset (P=0.001), higher systolic blood pressure (P=0.007), higher glycosylated hemoglobin A1c levels (P=0.001), high albuminuria (P=0.03), and use of insulin (P<0.001). For vision-threatening DR, four factors were significant: younger age at diabetic onset (P<0.001), higher systolic blood pressure (P=0.042), high albuminuria (P<0.001), and use of insulin (P<0.001).

CONCLUSION

The BDDES is the first large-scale ongoing cohort study of a Chinese urban population of persons with type 2 diabetes. Using standardized grading system comparable to large cohort studies from western populations, our baseline data shows that the prevalence of DR and major risk factors in this Chinese ethnic population are comparable to that found in the western population studies.

Genetically Determined Plasma Lipid Levels and Risk of Diabetic Retinopathy: A Mendelian Randomization Study

Results from observational studies examining dyslipidemia as a risk factor for diabetic retinopathy (DR) have been inconsistent. We evaluated the causal relationship between plasma lipids and DR using a Mendelian randomization approach. We pooled genome-wide association studies summary statistics from 18 studies for two DR phenotypes: any DR (N = 2,969 case and 4,096 control subjects) and severe DR (N = 1,277 case and 3,980 control subjects). Previously identified lipid-associated single nucleotide polymorphisms served as instrumental variables. Meta-analysis to combine the Mendelian randomization estimates from different cohorts was conducted. There was no statistically significant change in odds ratios of having any DR or severe DR for any of the lipid fractions in the primary analysis that used single nucleotide polymorphisms that did not have a pleiotropic effect on another lipid fraction. Similarly, there was no significant association in the Caucasian and Chinese subgroup analyses. This study did not show evidence of a causal role of the four lipid fractions on DR. However, the study had limited power to detect odds ratios less than 1.23 per SD in genetically induced increase in plasma lipid levels, thus we cannot exclude that causal relationships with more modest effect sizes exist.

Prevalence and risk factors for diabetic retinopathy in China: a multi-hospital-based cross-sectional study

Purpose

To determine the prevalence and risk factors for diabetic retinopathy (DR) and sight-threatening diabetic retinopathy (STDR) in a multi-hospital-based DR screening programme among patients with diabetes in China, the Lifeline Express Diabetic Retinopathy Screening Program.

Methods

Patients with diabetes in eight hospitals across mainland China (both southern and northern) from January 2014 to July 2016 were recruited in this programme. All participants underwent a standardised interview and examinations and received digital fundus photography. DR severity was graded from retinal fundus photographs by retina specialists in the reading centre of Joint Shantou International Eye Center, according to the grading standards of the English National Screening Programme. STDR was defined as the presence of preproliferative DR (R2), proliferative DR (R3) and/or maculopathy (M1).

Results

16 305 patients with diabetes were screened for DR in total. Fundus photographs were gradable for 15 078 patients (92.5%). The age–gender-standardised prevalence of any DR and STDR was 27.9% (95% CI, 27.2% to 28.6%) and 12.6% (95% CI, 12.1% to 13.1%), respectively. In the multiple logistic regression analysis, younger age (OR, 0.967), longer duration of diabetes (OR, 1.093), higher haemoglobin A1c (OR, 1.115), higher fasting plasma glucose (OR, 1.074), higher systolic blood pressure (OR, 1.014), faster heart rate (OR, 1.010), higher low-density lipoprotein (OR, 1.149), lower triglycerides (OR, 0.975), higher blood urea nitrogen (BUN) (OR, 1.012) and elevated serum creatinine level (OR, 1.003) were associated with the presence of DR. Similar risk factors, except for BUN and triglycerides, were found for STDR.

Conclusions

The prevalence of DR and STDR in diabetes was 27.9% and 12.6%, respectively in this multi-hospital-based population across China. Compared with Western population with diabetes, similar risk factors for DR and STDR were found in Chinese patients with diabetes.

Association of Diabetic Macular Edema and Proliferative Diabetic Retinopathy With Cardiovascular Disease: A Systematic Review and Meta-analysis

Importance

Previous studies on the relationship between diabetic retinopathy (DR) and cardiovascular disease (CVD) focused on the early stages of DR. Understanding whether patients with type 2 diabetes and severe stages of DR (diabetic macular edema [DME] and proliferative diabetic retinopathy [PDR]) have a higher risk of CVD will allow physicians to more effectively counsel patients.

Objective

To examine the association of severe stages of DR (DME and PDR) with incident CVD in patients with type 2 diabetes.

Data Sources

English-language publications were reviewed for articles evaluating the relationship of DR and CVD in MEDLINE, EMBASE, Current Contents, and the Cochrane Library from inception (January 1, 1950) to December 31, 2014, using the search terms diabetic retinopathy OR macular edema AND stroke OR cerebrovascular disease OR coronary artery disease OR heart failure OR myocardial infarction OR angina pectoris OR acute coronary syndrome OR coronary artery disease OR cardiomyopathy.

Study Selection

Among 656 studies screened for eligibility, 7604 individuals were included from 8 prospective population-based studies with data on photographic-based DR grading, follow-up visits, and well-defined incident CVD end point.

Data Extraction and Synthesis

Two independent reviewers conducted a systematic search of the 4 databases, and a single pooled database was developed. Incidence rate ratios (IRRs) were estimated for patients with DME, PDR, and vision-threatening DR, compared with persons without these conditions, by using individual participant data followed by a standard inverse-variance meta-analysis (2-step analysis). The review and analyses were performed from January 1, 2009, to January 1, 2017.

Main Outcome and Measures

Incident CVD, including coronary heart disease, stroke, or death from cardiovascular causes.

Results

Among 7604 patients with type 2 diabetes, the prevalence of DME was 4.6% and PDR, 7.4%. After a mean follow-up of 5.9 years (range, 3.2-10.1 years), 1203 incident CVD events, including 916 coronary heart disease cases, were reported. Persons with DME or PDR were more likely to have incident CVD (IRR, 1.39; 95% CI, 1.16-1.67) and fatal CVD (IRR, 2.33; 95% CI, 1.49-3.67) compared with those without DME or PDR.

Conclusions and Relevance

Patients with type 2 diabetes and DME or PDR have an increased risk of incident CVD, which suggests that these persons should be followed up more closely to prevent CVD.

Body mass index and risk of diabetic retinopathy: A meta-analysis and systematic review

Diabetic retinopathy (DR) is a frequent cause of acquired blindness worldwide. Various studies have reported the effects of body mass index (BMI) on the risk of DR, but the results remain controversial. Therefore, a meta-analysis was performed to evaluate the relationship between BMI and the risk of DR.A systematic search was performed using the Cochrane Library, PubMed, and Embase databases to obtain articles published through December 2016. Articles regarding the association between BMI and the risk of DR were retrieved. The adjusted odds ratios (ORs) and their 95% confidence intervals (CIs) were included and then pooled with a random effects model.A total of 27 articles were included in this meta-analysis. When BMI was analyzed as a categorical variable, neither being overweight (OR = 0.89, 95% CI 0.75-1.07; P = .21; I = 65%) nor obesity (OR = 0.97, 95% CI 0.73-1.30; P = .86) were associated with an increased risk of DR when compared with normal weight. When BMI was analyzed as a continuous variable, a higher BMI was not associated with an increased risk of DR (OR = 0.99, 95% CI 0.97-1.01; P = .25; I2 = 79%). The pooled results did not significantly change after the sensitivity analysis.Based on the current publications, neither being overweight nor obesity is associated with an increased risk of DR. Further studies should confirm these findings.

Is aspirin associated with diabetic retinopathy? The Singapore Epidemiology of Eye Disease (SEED) study

BACKGROUND/AIMS

To determine the association between aspirin use and diabetic retinopathy (DR) among persons with diabetes, in a population-based, cross-sectional study.

METHODS

Subjects with diabetes aged >40 years from the Singapore Epidemiology of Eye Diseases Study were enrolled in this study. Retinal photographs were graded for DR according to the modified Airlie House classification system. Vision threatening diabetic retinopathy (VTDR) was defined as the presence of severe non-proliferative DR, or proliferative DR, or clinically significant macular oedema. The association between aspirin use and the presence of DR or VTDR was assessed using multivariable logistic regression models including age, gender, ethnicity, socioeconomic status, HbA1c, systolic blood pressure, anti-hypertension medicine, total cholesterol, anti-cholesterol medicine, BMI, current smoking status, diabetes duration, history of cardiovascular disease (CVD) and chronic kidney disease (CKD.).

RESULTS

A total of 2,061 participants with diabetes and complete record of relevant systemic and DR data were included. Of these, 711 (34.5%) had any stage of DR, and among these 177 (8.6%) had VTDR. After adjusting for co-variables listed, the association between aspirin use and VTDR was significant (OR = 1.69, P = 0.019), while the association between aspirin use and any DR was borderline (OR = 1.31, P = 0.063). Aspirin use was not associated with either DR or VTDR after additional adjustment of CVD and CKD. Further stratification by history of CVD or CKD showed no association between aspirin use and DR/VTDR in either subgroup.

CONCLUSION

Aspirin use was not significantly associated with DR but might be an indicator of diabetic complications (CVD, CKD) that were co-present with more severe DR type. Future longitudinal studies are warranted to confirm our findings.

The Prevalence of Diabetic Retinopathy in Australian Adults with Self-Reported Diabetes: The National Eye Health Survey

PURPOSE

To determine the prevalence of and factors associated with diabetic retinopathy (DR) among non-Indigenous and Indigenous Australian adults with self-reported diabetes.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

Non-Indigenous Australians (50-98 years of age) and Indigenous Australians (40-92 years of age) with known diabetes.

METHODS

Diabetes was determined based on self-report of previous diagnosis of the disease. Nonmydriatic fundus photographs were obtained of each eye and graded according to the modified Airlie House classification system.

MAIN OUTCOME MEASURES

Any DR, vision-threatening DR (VTDR), treatment coverage rates (proportion of participants with proliferative DR [PDR], clinically significant macular edema [CSME], or both who had evidence of retinal scatter and focal laser treatment).

RESULTS

Four hundred thirty-one non-Indigenous Australians (13.9%) and 645 Indigenous Australians (37.1%) self-reported diabetes, of whom 93% (1004/1076) had retinal images that were gradable for DR. The sampling weight-adjusted prevalence of any DR and VTDR among non-Indigenous adults with self-reported diabetes was 28.5% (95% confidence interval [CI], 22.6-35.3) and 4.5% (95% CI, 2.6-7.9), respectively. Among adults 40 years of age and older, the sampling weight-adjusted prevalence of any DR and VTDR was 39.4% (95% CI, 33.1-46.1) and 9.5% (95% CI, 6.8-13.1), respectively. Longer diabetes duration was associated significantly with VTDR in the Indigenous Australian population (odds ratio [OR], 1.08 per 1-year increase; P = 0.005) and non-Indigenous Australian population (OR, 1.05 per 1-year increase; P = 0.03). The treatment coverage of PDR and CSME was 75% (56/75) in Indigenous Australians and 79% (15/19) in non-Indigenous Australians. Diabetic retinopathy was attributed as the main cause of vision loss (<6/12 in the better eye) in 9% and 19% of non-Indigenous and Indigenous Australian adults with known diabetes, respectively.

CONCLUSIONS

Three quarters of non-Indigenous and Indigenous Australian adults with PDR or CSME have received laser treatment. The prevalence of VTDR in Indigenous and non-Indigenous Australians in the present study was lower than that found in previous population-based reports, nevertheless, approximately 1 in 10 Indigenous adults with known diabetes experience VTDR. This highlights that intensified prevention strategies are required to delay or prevent avoidable vision loss resulting from DR in Indigenous Australian communities.

Global Estimates on the Number of People Blind or Visually Impaired by Diabetic Retinopathy: A Meta-analysis From 1990 to 2010

OBJECTIVE

To estimate global and regional trends from 1990 to 2010 of the prevalence and number of persons visually impaired specifically by diabetic retinopathy (DR), as a complication of the precipitous trends in global diabetes, is fundamental for health planning purposes.

RESEARCH DESIGN AND METHODS

The meta-analysis of published population studies from 1990 to 2012 for the Global Burden of Disease Study 2010 (GBD) yielded estimated global regional trends in DR among other causes of moderate and severe vision impairment (MSVI; presenting visual acuity <6/18, ≥3/60) and blindness (presenting visual acuity <3/60).

RESULTS

Globally in 2010, out of overall 32.4 million blind and 191 million visually impaired people, 0.8 million were blind and 3.7 million were visually impaired because of DR, with an alarming increase of 27% and 64%, respectively, spanning the two decades from 1990 to 2010. DR accounted for 2.6% of all blindness in 2010 and 1.9% of all MSVI worldwide, increasing from 2.1% and 1.3%, respectively, in 1990. These figures were lower in regions with younger populations (<2% in East and Southeast Asia and Oceania) than in high-income regions (North America, Western Europe, and Australasia) with relatively aging populations (>4%).

CONCLUSIONS

The number of persons with visual impairment due to DR worldwide is rising and represents an increasing proportion of all blindness/MSVI causes. Age-standardized prevalence of DR-related blindness/MSVI was higher in sub-Saharan Africa and South Asia. One out of 39 blind people had blindness due to DR, and 1 out of 52 visually impaired people had visual impairment due to DR.

Prevalence, Correlates, and Impact of Uncorrected Presbyopia in a Multiethnic Asian Population

PURPOSE

To examine the prevalence, correlates, and impact of uncorrected presbyopia on vision-specific functioning (VF) in a multiethnic Asian population.

DESIGN

Population-based cross-sectional study.

METHODS

We included 7890 presbyopic subjects (3909 female; age range, 40-86 years) of Malay, Indian, and Chinese ethnicities from the Singapore Epidemiology of Eye Disease study. Presbyopia was classified as corrected and uncorrected based on self-reported near correction use. VF was assessed with the VF-11 questionnaire validated using Rasch analysis. Multivariable logistic and linear regression models were used to investigate the associations of sociodemographic and clinical parameters with uncorrected presbyopia, and its impact on VF, respectively. As myopia may mitigate the impact of noncorrection, we performed a subgroup analysis on myopic subjects only (n = 2742).

RESULTS

In total, 2678 of 7890 subjects (33.9%) had uncorrected presbyopia. In multivariable models, younger age, male sex, Malay and Indian ethnicities, presenting distance visual impairment (any eye), and lower education and income levels were associated with higher odds of uncorrected presbyopia (all P < .05). Compared with corrected presbyopia, noncorrection was associated with worse overall VF and reduced ability to perform individual near and distance vision-specific tasks even after adjusting for distance VA and other confounders (all P < .05). Results were very similar for myopic individuals.

CONCLUSION

One-third of presbyopic Singaporean adults did not have near correction. Given its detrimental impact on both near and distance VF, public health strategies to increase uptake of presbyopic correction in younger individuals, male individuals, and those of Malay and Indian ethnicities are needed.

Cystatin C, chronic kidney disease and retinopathy in adults without diabetes

BACKGROUND

Serum cystatin C, a novel marker of renal function has been shown to be superior to serum creatinine in predicting renal function decline and adverse outcomes of chronic kidney disease (CKD). Our aim was to investigate the association between cystatin C and retinopathy in adults without diabetes.

METHODS

We examined 1725 Indian adults, aged 40-80 years who participated in the Singapore Indian Eye Study (2007-2009) and were free of diabetes mellitus. CKD was defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2) determined from serum cystatin C (CKD-eGFRcys, n = 199), and serum creatinine (CKD-eGFRcr, n = 81). Retinopathy was assessed from digital fundus photographs of both eyes by trained graders using the modified Airlie House classification. The associations of CKD defined by the two markers alone and in combination (confirmed CKD, eGFRcr <60 and eGFRcys <60, n = 58) with retinopathy were examined using logistic regression models adjusted for potential confounding factors including preexisting cardiovascular disease and albuminuria.

RESULTS

The prevalence of retinopathy among those with CKD-eGFRcr and CKD-eGFRcys was 9.9% and 8.5%, respectively. In separate models, the associations of retinopathy with both CKD-eGFRcys (odds ratio (OR) (95% confidence interval (CI)) = 2.18 (1.14-4.16)) and CKD-eGFRcr were significant (OR (95% CI) = 2.63 (1.10-6.28)). In models including both markers, compared to optimal kidney function (eGFRcr ≥60 and eGFRcys ≥60), confirmed CKD was associated with a fourfold higher odds of retinopathy (OR (95% CI) = 4.01 (1.52-10.60)).

CONCLUSIONS

In a population-based sample of Indian adults without diabetes, CKD defined by both cystatin C and creatinine was strongly associated with retinopathy.

Prevalence of Diabetic Retinopathy and Vision Loss in the Beijing Eye Study: the Potential Role of the Cerebrospinal Fluid Pressure

In the Beijing Eye Study, a population-based study carried out in 2001, 2006, and 2011, prevalence of diabetic retinopathy (DR) was 2.9 ± 0.3 % (95 % confidence interval 2.3, 3.5) per individual in 2011. Correspondingly, only 1.1 % of blindness and 0.8 % of visual impairment were caused by DR in East Asia. As in other populations, prevalence, severity, and 10-year incidence of DR were associated with higher levels of HbA1c, higher blood glucose concentration, longer known duration of diabetes, lower educational level, and higher blood pressure. Interestingly, the presence, severity, and 10-year incidence of DR were additionally correlated with higher estimated cerebrospinal fluid pressure and shorter ocular length. Higher cerebrospinal fluid pressure may lead to higher retinal vein pressure and subsequently higher retinal capillary blood pressure increasing fluid and blood extravasation. Shorter axial length or hyperopia may be associated with higher intraocular concentration of cytokines. Aging of the society, improvements in medical infrastructure, and lifestyle changes may profoundly increase prevalence of, and burden by, DR in China in the future.

Incidence Density and Risk Factors of Diabetic Retinopathy Within Type 2 Diabetes: A Five-Year Cohort Study in China (Report 1)

A prospective study was carried out from August 2010 to August 2014 in the community of Fengyutan (China). Six hundred and twenty two T2D subjects were collected. The incidence density of diabetic retinopathy (DR) was 1.81% person-year (95% confidence interval, CI: 1.21–2.43% person-year). After a Cox regression model analysis and adjusted confounding factors, independent predictors related to the incidence of DR including male gender (adjusted hazard ratios, aHR: 1.47, 95% CI: 1.21–1.62), with hypertension (aHR: 1.49, 95%: 1.12–1.73), duration of diabetes > 10 years (aHR: 2.28, 95%: 2.05–2.42), uncontrolled diabetes (aHR: 1.76, 95%: 1.41–2.01), total cholesterol ≥ 200 mg/dL (aHR: 1.54, 95%: 1.34–1.72) and HbA1c ≥ 7% (mmol/mol) (aHR: 2.12, 95%: 1.87–2.32). Duration of T2D revealed the significantly dose-response relationship to the onset of DR. The incidence density of DR in the Chinese community was relatively low in comparison with other studies. More attention should be paid to the T2D patients, especially of male gender, with hypertension, longer duration of diabetes, uncontrolled diabetes, total cholesterol ≥ 200mg/dL and HbA1c ≥ 7% (mmol/mol).

Prevalence and Cardiovascular Associations of Diabetic Retinopathy and Maculopathy: Results from the Gutenberg Health Study

Objective

Diabetic retinopathy (DR) is the leading cause of blindness in people of working age. The purpose of this paper is to report the prevalence and cardiovascular associations of diabetic retinopathy and maculopathy (DMac) in Germany.

Research Design and Methods

The Gutenberg Health Study (GHS) is a population-based study with 15,010 participants aged between 35 at 74 years from the city of Mainz and the district of Mainz-Bingen. We determined the weighted prevalence of DR and DMac by assessing fundus photographs of persons with diabetes from the GHS data base. Diabetes was defined as HbA1c ≥ 6.5%, known diagnosis diabetes mellitus or known diabetes medication. Furthermore, we analysed the association between DR and cardiovascular risk factors and diseases.

Results

Overall, 7.5% (1,124/15,010) of the GHS cohort had diabetes. Of these, 27.7% were unaware of their disease and thus were newly diagnosed by their participation in the GHS. The prevalence of DR and DMac was 21.7% and 2.3%, respectively among patients with diabetes. Vision-threatening disease was present in 5% of the diabetic cohort. In the multivariable analysis DR (all types) was associated with age (Odds Ratio [95% confidence interval]: 0.97 [0.955–0.992]; p = 0.006) arterial hypertension (1.90 [1.190–3.044]; p = 0.0072) and vision-threatening DR with obesity (3.29 [1.504–7.206]; p = 0.0029). DR (all stages) and vision-threatening DR were associated with duration of diabetes (1.09 [1.068–1.114]; p<0.0001 and 1.18 [1.137–1.222]; p<0.0001, respectively).

Conclusions

Our calculations suggest that more than a quarter-million persons have vision-threatening diabetic retinal disease in Germany. Prevalence of DR was lower in the GHS compared to East-Asian studies. Associations were found with age, arterial hypertension, obesity, and duration of diabetes mellitus.

The metabolic syndrome and severity of diabetic retinopathy

BACKGROUND

While metabolic syndrome has been strongly implicated as a risk factor for macrovascular diseases, such as stroke and cardiovascular disease, its relationship with microvascular diseases, including diabetic retinopathy, has been less defined. The purpose of this pilot study was to investigate the association between metabolic syndrome and the presence and severity of diabetic retinopathy.

METHODS

A retrospective case-control chart review at the University of Iowa ophthalmology and primary care clinics included 100 patients with proliferative diabetic retinopathy (PDR), 100 patients with nonproliferative diabetic retinopathy (NPDR), 100 diabetic patients without diabetic retinopathy, and 100 nondiabetic patients who were randomly selected. Using the International Diabetes Foundation definition, the prevalence of metabolic syndrome and the number of components of metabolic syndrome were compared among these groups.

RESULTS

The prevalence of metabolic syndrome in patients with diabetes was 69.3%, which was significantly higher than that in patients without diabetes (27%; P<0.0001) (odds ratio [OR] =6.28; 95% confidence interval [CI]: 3.76-10.49; P=0.0004). However, there was no significant difference in the prevalence of metabolic syndrome between diabetics with and without diabetic retinopathy, with rates of 67.5% and 73%, respectively (P=0.36) (OR =0.77; 95% CI: 0.45-1.32; P=0.34). In addition, there was no significant difference between the PDR and NPDR groups, with rates of 63% and 72%, respectively (P=0.23) (OR =0.70; 95% CI: 0.38-1.30; P=0.26).

CONCLUSION

The metabolic syndrome was highly prevalent in patients with diabetes, but it was not associated with the presence or severity of retinopathy.

The Prevalence of Age-Related Eye Diseases and Cataract Surgery among Older Adults in the City of Lodz, Poland

Purpose. To determine the prevalence of age-related eye diseases and cataract surgery among older adults in the city of Lodz, in central Poland. Material and Methods. The study design was cross-sectional and observational study. A total of 1107 women and men of predominantly Caucasian origin were successfully enumerated and recruited for the study. All selected subjects were interviewed and underwent detailed ophthalmic examinations. Results. Overall 8.04% (95% CI 6.44-9.64) subjects had cataract surgery in either eye. After excluding subjects with bilateral cataract surgery, the prevalence of cataract was 12.10% (95% CI 10.18-14.03). AMD was found in 4.33% (95% CI 3.14-5.54 ) of all subjects. Of them 3.25% (95% CI 2.21-4.30 ) had early AMD and 1.08% (95% CI 0.47-1.69) had late AMD. Various types of glaucoma were diagnosed in 5.51% (95% CI 4.17-6.85) of subjects and 2.62% (95% CI 1.68-3.56) had OHT. The prevalence rates of DR and myopic macular degeneration were 1.72% (95% CI 0.95-2.48) and 0.45% (95% CI 0.06-0.85), respectively. All multiple logistic regression models were only significantly associated with older age. The highest rate of visual impairment was observed among subjects with retinal diseases. Conclusions. The study revealed high prevalence of age-related eye diseases in this older population.

Prevalence and risk factors for retinopathy in persons without diabetes: the Singapore Indian Eye Study

PURPOSE

To describe prevalence and risk factors for retinopathy in an Asian Indian population without diabetes.

METHODS

A population-based cross-sectional study of 3400 Indians aged 40-80 years residing in Singapore was conducted. Retinopathy was assessed from retinal photographs by trained graders using modified Airlie House Classification System. Risk factors were assessed from standardized interviews, clinical examinations and laboratory investigations. Diabetes mellitus was defined as glycosylated haemoglobin ≥6.5%, use of diabetic medication or physician diagnosis of diabetes.

RESULTS

Among the 1900 individuals without diabetes, mean HbA1c was 5.7% and mean systolic blood pressure was 132.4 mmHg. Age-standardized prevalence of retinopathy was 5.05% (n = 98; 95% confidence interval [CI], 4.07-6.21), with no significant difference in retinopathy prevalence between males (6.15%) and females (4.13%). Among non-diabetic persons with retinopathy, 96.9% (n = 95) had signs of minimal-to-mild retinopathy while 3.06% (n = 3) had moderate-to-severe retinopathy. After adjusting for multiple covariables, retinopathy signs were associated with higher levels of HbA1c (odds ratio [OR], 2.4; 95% CI, 1.3-4.5; per% increase), systolic blood pressure (OR, 1.02; 95% CI, 1.01-1.03; per mmHg increase) and serum creatinine (OR, 1.005; 95% CI, 1.002-1.009; per mm increase), but not C-reactive protein, cigarette smoking or lipid levels.

CONCLUSION

One in 20 Asian Indian persons without diabetes had retinopathy signs. Risk factors for these signs include higher glycosylated haemoglobin, systolic blood pressure and serum creatinine.

Bevacizumab treatment reduces retinal neovascularization in a mouse model of retinopathy of prematurity

AIM

To evaluate the effect of different bevacizumab concentrations on retinal neovascularization in a retinopathy of prematurity (ROP) mouse model.

METHODS

A total of 60 of C57BL/6 J mice were exposed to 75%±2% oxygen from postnatal d7 to postnatal d12. Fifteen nonexposed mice served as negative controls (group A). On d12, 30 mice (group C) were injected with 2.5 µg intravitreal bevacizumab (IVB), 30 mice (group D) were injected with 1.25 µg IVB in one eye. The contralateral eyes were injected with balanced salt solution (BSS) (control group=group B). The adenosine diphosphatase (ADPase) histochemical technique was used for retinal flat mount to assess the oxygen-induced changes of retinal vessels. Neovascularization was quantified by counting the endothelial cell proliferation on the vitreal side of the inner limiting membrane of the retina. Histological changes were examined by light microscopy. The mRNA levels of vascular endothelial growth factor (VEGF) were quantified by Real-time PCR. Western-blotting analysis was performed to examine the expression of P-VEGFR.

RESULTS

Comparing with the control group B, regular distributions and reduced tortuosity of vessels were observed in our retinal flat mounts in groups C and D. The endothelial cell count per histological section was lower in groups C (P<0.0001) and D (P<0.0001) compared with the control group B. Histological evaluation showed no retinal toxicity in any group. In all oxygen treated groups VEGF mRNA expression was significantly increased as compared to age-matched controls. No significant change in VEGF mRNA expression could be achieved in either of the treatments or the oxygen controls. The results of the Western blot were consistent with that of the Real-time PCR analysis.

CONCLUSION

An intravitreal injection of Bevacizumab is able to reduce angioproliferative retinopathy in a mouse model for oxygen-induced retinopathy.

Alterations of retinal vasculature in cystathionine-β-synthase heterozygous mice: a model of mild to moderate hyperhomocysteinemia

Mild to moderate hyperhomocysteinemia is prevalent in humans and is implicated in neurovascular diseases, including recently in certain retinal diseases. Herein, we used hyperhomocysteinemic mice deficient in the Cbs gene encoding cystathionine-β-synthase (Cbs(+/-)) to evaluate retinal vascular integrity. The Cbs(+/+) (wild type) and Cbs(+/-) (heterozygous) mice (aged 16 to 52 weeks) were subjected to fluorescein angiography and optical coherence tomography to assess vasculature in vivo. Retinas harvested for cryosectioning or flat mount preparations were subjected to immunofluorescence microscopy to detect blood vessels (isolectin-B4), angiogenesis [anti-vascular endothelial growth factor (VEGF) and anti-CD105], gliosis [anti-glial fibrillary acidic protein (GFAP)], pericytes (anti-neural/glial antigen 2), blood-retinal barrier [anti-zonula occludens protein 1 (ZO-1) and anti-occludin], and hypoxia [anti-pimonidazole hydrochloride (Hypoxyprobe-1)]. Levels of VEGF, GFAP, ZO-1, and occludin were determined by immunoblotting. Results of these analyses showed a mild vascular phenotype in young mice, which progressed with age. Fluorescein angiography revealed progressive neovascularization and vascular leakage in Cbs(+/-) mice; optical coherence tomography confirmed new vessels in the vitreous by 1 year. Immunofluorescence microscopy demonstrated vascular patterns consistent with ischemia, including a capillary-free zone centrally and new vessels with capillary tufts midperipherally in older mice. This was associated with increased VEGF, CD105, and GFAP and decreased ZO-1/occludin levels in the Cbs(+/-) retinas. Retinal vein occlusion was observed in some Cbs(+/-) mouse retinas. We conclude that mild to moderate elevation of homocysteine in Cbs(+/-) mice is accompanied by progressive alterations in retinal vasculature characterized by ischemia, neovascularization, incompetent blood-retinal barrier, and vascular occlusion.

Sex differences in risk factors for retinopathy in non-diabetic men and women: the Tromsø Eye Study

PURPOSE

  To determine the prevalence and risk factors for retinopathy in a nondiabetic population.

METHODS

  The study population included 5869 participants without diabetes aged 38-87 years from the Tromsø Eye Study, a substudy of the population-based Tromsø Study in Norway. Retinal images from both eyes were graded for retinopathy. We collected data on risk factors from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. The cross-sectional relationship between potential risk factors and retinopathy was assessed using logistic regression analysis.

RESULTS

  The overall prevalence of retinopathy was 14.8%. Men had a higher prevalence of retinopathy compared with women (15.9% versus 14.0%, p=0.04). In men, retinopathy was associated with hypertension (odds ratio [OR], 1.59; 95% confidence interval [CI], 1.24-2.04) and HbA1c (OR per %, 1.41; 95% CI, 1.01-1.96). In women, retinopathy was associated with age (OR per 10 years, 1.32; 95% CI, 1.14-1.52), log-transformed urinary albumin excretion (OR per log unit, 1.46; 95% CI, 1.14-1.87) and hypertension (OR, 1.36; 95% CI, 1.08-1.71). In women, retinopathy was associated with very low levels of urinary albumin excretion (urinary albumin/creatinine ratio >0.43 mg/mmol).

CONCLUSION

  This study confirms results from previous studies on the strong association between blood pressure and retinopathy. A novel finding is the sex differences in risk factors for retinopathy, suggesting a sex difference in the pathogenesis leading to retinopathy.

Review of the prevalence of diabetic retinopathy in Indigenous Australians

The purpose of this review is to compare the prevalence of diabetic retinopathy (DR) between Indigenous and non-Indigenous Australians with Diabetes Mellitus (DM). Australian DR prevalence data from 6 Indigenous studies (n = 2865) and 5 non-Indigenous studies (n = 9801) conducted between 1985 and 2013 were included for analysis. Estimated prevalence of any DR among Indigenous Australians with DM was 23.4% compared with 28.9% for non-Indigenous Australians (χ(2)  = 26.9, P < 0.001). In studies performed after 1990, a significantly higher rate of diabetic macular edema was found in Indigenous compared with non-Indigenous Australians with DM (7.6% versus 4.9%, χ(2)  = 6.67, P = 0.01). Although there are limitations in comparing these studies, one explanation for the observed data could be a model in which Indigenous Australians are relatively resistant to early stage DR, but with a subset progressing to sight threatening DR due to individual genetic and environmental susceptibility factors coupled with poor glycemic control.

Visual functions and disability in diabetic retinopathy patients

PURPOSE

This study was undertaken to find correlations between visual functions and visual disabilities in patients with diabetic retinopathy.

METHOD

A cross-sectional study was carried out among 38 visually impaired diabetic retinopathy subjects at the Low Vision Clinic of B.P. Koirala Lions Centre for Ophthalmic Studies, Kathmandu. The subjects underwent assessment of distance and near visual acuity, objective and subjective refraction, contrast sensitivity, color vision, and central and peripheral visual fields. The visual disabilities of each subject in their daily lives were evaluated using a standard questionnaire. Multiple regression analysis between visual functions and visual disabilities index was assessed.

RESULT

The majority of subjects (42.1%) were of the age group 60-70 years. Best corrected visual acuity was found to be 0.73±0.2 in the better eye and 0.93±0.27 in the worse eye, which was significantly different at p=0.002. Visual disability scores were significantly higher for legibility of letters (1.2±0.3) and sentences (1.4±0.4), and least for clothing (0.7±0.3). Visual disability index for legibility of letters and sentences was significantly correlated with near visual acuity and peripheral visual field. Contrast sensitivity was also significantly correlated with the visual disability index, and total scores.

CONCLUSION

Impairment of near visual acuity, contrast sensitivity, and peripheral visual field correlated significantly with different types of visual disability. Hence, these clinical tests should be an integral part of the visual assessment of diabetic eyes.

Tromsø eye study: prevalence and risk factors of diabetic retinopathy

PURPOSE

To determine the prevalence of visual impairment, retinopathy and macular oedema, and assess risk factors for retinopathy in persons with diabetes.

METHODS

The present study included 514 participants with diabetes aged 46-87 years from the Tromsø Eye Study, a sub-study of the population-based Tromsø Study in Norway. Visual acuity was measured using an auto-refractor. Retinal images from both eyes were graded for retinopathy and macular oedema. We collected data on risk factor exposure from self-report questionnaires, clinical examinations, laboratory measurements and case note reviews. Regression models assessed the cross-sectional relationship between potential risk factors and diabetic retinopathy.

RESULTS

The prevalence of visual impairment (corrected Snellen visual acuity <20/60 in the better-seeing eye) was 1.6%. The prevalence of diabetic retinopathy was 26.8% and macular oedema 3.9%. In a multivariable logistic regression model, retinopathy was associated with longer diabetes duration (odds ratio, OR 1.07, 95% CI 1.03-1.11), insulin use (OR 2.14, 95% CI 1.19-3.85), nonfasting glucose (OR 1.07, 95% CI 1.00-1.15) and microalbuminuria (OR 1.89, 95% CI 1.28-2.81). Sub-group analyses showed association between retinopathy and even low levels of microalbuminuria (1.16 mg/mmol).

CONCLUSION

The findings suggest that low levels of microalbuminuria may be a useful risk predictor for identifying individuals with diabetes at high risk of retinopathy. The study confirms previous findings that insulin use, longer diabetes duration and higher levels of blood glucose are associated with retinopathy in persons with diabetes. The prevalence of diabetic retinopathy was similar as reported in other studies.