Diabetes and diabetic retinopathy in a Mexican-American population: Proyecto VER

Longitudinal Trends and Disparities in Diabetic Retinopathy Within an Aggregate Health Care Network

Importance

Diabetic retinopathy (DR) is a leading cause of blindness in the US, warranting updates on its prevalence and incidence in the setting of advancements in diabetic care over recent years.

Objective

To determine recent trends in DR prevalence stratified by baseline demographics to identify those populations at greater risk.

Design, Setting, and Participants

This was a cross-sectional epidemiologic evaluation conducted using deidentified data from the large federated TriNetX Analytics health research network composed of 56 health care organizations in the US. Patients from 2015 to 2022 who had an International Statistical Classification of Diseases and Related Health Problems, Tenth Revision code of type 1 DR (T1DR) or type 2 DR (T2DR) were included in this analysis. Patients were further stratified by age cohorts (20-29 years, 30-39 years, 40-49 years, 50-59 years, 60-69 years, and 70 years or older), race and ethnicity, and sex.

Main Outcomes and Measures

Prevalence per 100 000 patients and prevalence odds ratios (ORs) were calculated in Microsoft Excel and Posit (formerly RStudio).

Results

A total of 359 126 patients with T1DR or T2DR (mean [SD] age, 67 [14] years; 52% female) were included in this study between January 1, 2015, and December 21, 2022. T1DR increased in prevalence from 2015 to 2022, with T1DR increasing 1.15-fold affecting 70.4 patients per 100 000 in 2022. T2DR increased 1.07-fold affecting 461.7 patients per 100 000 in 2022. For T1DR, the cohort aged 20 to 39 years had the most substantial increase at 4.7 and 1.96 fold. Overall, White males had the largest prevalence ORs of T1DR at 1.41 (95% CI, 1.36-1.47) compared with White females (reference group). In T2DR, patients aged 20 to 39 years again had a 2.5- and 1.6-fold prevalence increase from 2015 to 2022. Regardless of age group, Hispanic males demonstrated larger prevalence OR at 4.08 (95% CI, 3.97-4.19) compared with White females followed by Hispanic females at 2.49 (95% CI, 2.42-2.56), Black males at 2.23 (95% CI, 2.17-2.29), and Black females at 2.00 (95% CI, 1.95-2.05).

Conclusion and Relevance

The prevalence of both T1DR and T2DR increased in this network from 2015 to 2022, with individuals aged 20 to 39 years showing large increases. Additionally, T2DR was associated with greater increases in both Hispanic and Black communities. These findings support DR screening in young adults and for T2DR interventions specifically designed for racial and ethnic minoritized patients most affected by disease. Future investigations are warranted to further investigate these trends among young adults.

Pharmacist-Managed Diabetic Retinopathy in Hispanic/LatinX Population

There are three major microvascular complications of diabetes, retinopathy, nephropathy, and neuropathy, among which diabetic retinopathy (DR) is the most common. Several studies suggest that the Hispanic/LatinX population exhibit the highest cases of both diabetes and DR. Strategies aimed at reducing risk factors that could minimize the likelihood of DR development or progression could be beneficial. This retrospective study assessed DR in the Hispanic/LatinX population in pharmacist-managed cardiovascular risk reduction services. A chart review was conducted for 60 individuals who visited clinics led by both a pharmacist and a primary care physician (intervention group) and 178 individuals who saw physicians only (control group). Demographics, metabolic parameters, DR severity, and pharmacist appointment data were collected. The highest benefit of pharmacist intervention was observed in terms of a greater but insignificant decrease in HbA1c; however, there was no benefit of pharmacist's intervention on DR in general, likely due to the longer duration of diabetes and higher HbA1c at the beginning of the study. When the DR progression was examined based on the frequency of pharmacy visits, individuals who met a pharmacist more than two times per year showed more stable and lesser worsening of DR. Overall, our studies suggest that pharmacist intervention could benefit retinopathy outcome; however, well-known determinants of DR such as good glycemic control and duration of diabetes still play a critical role, in addition to challenges in receiving healthcare by the Hispanic/LatinX population. Future strategies in a prospective manner could help retinopathy outcomes in these at-risk patient populations.

Healthcare Resource Utilization and Costs in an At-Risk Population With Diabetic Retinopathy

Purpose

Several investigators have suggested the cost-effectiveness of earlier screening, management of risk factors, and early treatment for diabetic retinopathy (DR). We aimed to evaluate the extent of health care utilization and cost of delayed care by insurance type in a vulnerable patient population.

Methods

A retrospective analysis of patients with DR was conducted using electronic medical record (EMR) data from January 2014 to December 2020 at Denver Health Medical Center, a safety net institution. Patients were classified by disease severity and insurance status. DR-specific costs were assessed via Current Procedural Terminology (CPT) codes over a 24-month follow-up period.

Results

Among the 313 patients, a higher proportion of non-English speaking patients were uninsured. Rates of proliferative DR at presentation differed across insurance groups (62% of uninsured, 42% of discount plan, and 33% of Medicare/Medicaid, P = 0.016). There was a significant difference in the total median cost between discount plan patients ($1258, interquartile range [IQR] = $0 - $5901) and both Medicare patients ($751, IQR = $0, $7148, P = 0.037) and Medicaid patients ($593, IQR = $0 - $6299, P = 0.025).

Conclusions

There were higher rates of proliferative DR at presentation among the uninsured and discount plan patients and greater total median cost in discount plan patients compared to Medicare or Medicaid. These findings prioritize mitigating gaps in insurance coverage and barriers to preventative care among vulnerable populations.

Translational Relevance

Advanced diabetic disease and increased downstream health care utilization and cost vary across insurance type, suggesting improved access to preventative care is needed in these specific at-risk populations.

Risk Factors for Diabetic Retinopathy in Latin America (Mexico) and the World: A Systematic Review and Meta-Analysis

Diabetic retinopathy (DR) is one of the main complications of diabetes, and the management of the main control parameters explains only an 11% reduction in the risk of progressing to DR, leaving 89% to be explained by other factors or correlations between the usual factors that are currently unknown. The objective of this systematic review and meta-analysis is to evaluate the similarities and differences between the possible risk factors for developing DR when comparing the world to Latin American populations. The search was performed first for Latin American (LA) populations and a second search for non-Latin American (Non-LA) populations. Using the PRISMA guidelines, five articles were found to be relevant for each of the groups. The patients who had elevated systolic blood pressure (SBP) developed DR more frequently than the patients without retinopathy (Z = 2.1, p = 0.03), an effect measured in the population at a global level (GL), behavior that becomes not significant when the LA and non-LA populations are grouped separately; relevant to this is that the diagnosis of hypertension (HBP) grouped globally and stratified does not present a risk factor for DR (Z = 0.79, p = 0.42). This indicates that SBP is a risk factor for the world population and that, by separating it into different regions, the omission could cause it not to be considered a possible risk factor. In conclusion, the relationship between the increase in DR associated with the risk factors present in different populations, the limited research conducted in Latin America, and the cultural, social, economic, and genetic differences makes for a complex condition, which reflects the necessity of researching in a more integrated way.

Limited English Proficiency Is Associated With Diabetic Retinopathy in Patients Presenting for Cataract Surgery

Purpose

To investigate the relationship between limited English proficiency (LEP) and diabetic retinopathy (DR) in patients presenting for cataract surgery.

Methods

This is a retrospective observational study of patients who underwent cataract surgery between January 2014 and February 2020. Patients who self-identified as needing or preferring an interpreter were defined as having LEP. Differences in demographics, characteristics, and outcomes including history of type 2 diabetes (T2DM), DR, preoperative best corrected visual acuity (BCVA), macular edema, and anti-vascular endothelial growth factor injections were analyzed. Statistical comparisons were assessed using logistic regression with generalized estimating equations.

Results

We included 13,590 eyes. Of these, 868 (6.4%) were from LEP patients. Patients with LEP were more likely to be Hispanic (P < 0.001), female sex (P = 0.008), or older age (P = 0.003) and have worse mean BCVA at presentation (P < 0.001). Patients with LEP had a significantly higher rate of T2DM (P < 0.001), macular edema (P = 0.033), and DR (18.1% vs. 5.8%, P < 0.001). Findings remained significant when controlling for age, sex, race/ethnicity, and type of health insurance. Patients with LEP and DR were more likely to have had later stages of DR (P = 0.023).

Conclusions

Patients with LEP presenting for cataract surgery had a higher rate of DR and associated complications compared to patients with English proficiency. Further studies are needed to understand how language disparities influence health and what measures could be taken to improve healthcare in this vulnerable population.

Translational Relevance

Our study highlights healthcare disparities within ophthalmology and emphasizes the importance of advocating for improved healthcare delivery for patients with LEP.

Considerations for addressing bias in artificial intelligence for health equity

Health equity is a primary goal of healthcare stakeholders: patients and their advocacy groups, clinicians, other providers and their professional societies, bioethicists, payors and value based care organizations, regulatory agencies, legislators, and creators of artificial intelligence/machine learning (AI/ML)-enabled medical devices. Lack of equitable access to diagnosis and treatment may be improved through new digital health technologies, especially AI/ML, but these may also exacerbate disparities, depending on how bias is addressed. We propose an expanded Total Product Lifecycle (TPLC) framework for healthcare AI/ML, describing the sources and impacts of undesirable bias in AI/ML systems in each phase, how these can be analyzed using appropriate metrics, and how they can be potentially mitigated. The goal of these "Considerations" is to educate stakeholders on how potential AI/ML bias may impact healthcare outcomes and how to identify and mitigate inequities; to initiate a discussion between stakeholders on these issues, in order to ensure health equity along the expanded AI/ML TPLC framework, and ultimately, better health outcomes for all.

Prevalence of Diabetic Retinopathy in the US in 2021

Importance

Diabetic retinopathy (DR) is a common microvascular complication of diabetes and a leading cause of blindness among working-age adults in the US.

Objective

To update estimates of DR and vision-threatening diabetic retinopathy (VTDR) prevalence by demographic factors and US county and state.

Data Sources

The study team included data from the National Health and Nutrition Examination Survey (2005 to 2008 and 2017 to March 2020), Medicare fee-for-service claims (2018), IBM MarketScan commercial insurance claims (2016), population-based studies of adult eye disease (2001 to 2016), 2 studies of diabetes in youth (2021 and 2023), and a previously published analysis of diabetes by county (2012). The study team used population estimates from the US Census Bureau.

Study Selection

The study team included relevant data from the US Centers for Disease Control and Prevention's Vision and Eye Health Surveillance System.

Data Extraction and Synthesis

Using bayesian meta-regression methods, the study team estimated the prevalence of DR and VTDR stratified by age, a nondifferentiated sex and gender measure, race, ethnicity, and US county and state.

Main Outcomes and Measures

The study team defined individuals with diabetes as those who had a hemoglobin A1c level at 6.5% or more, took insulin, or reported ever having been told by a physician or health care professional that they have diabetes. The study team defined DR as any retinopathy in the presence of diabetes, including nonproliferative retinopathy (mild, moderate, or severe), proliferative retinopathy, or macular edema. The study team defined VTDR as having, in the presence of diabetes, severe nonproliferative retinopathy, proliferative retinopathy, panretinal photocoagulation scars, or macular edema.

Results

This study used data from nationally representative and local population-based studies that represent the populations in which they were conducted. For 2021, the study team estimated 9.60 million people (95% uncertainty interval [UI], 7.90-11.55) living with DR, corresponding to a prevalence rate of 26.43% (95% UI, 21.95-31.60) among people with diabetes. The study team estimated 1.84 million people (95% UI, 1.41-2.40) living with VTDR, corresponding to a prevalence rate of 5.06% (95% UI, 3.90-6.57) among people with diabetes. Prevalence of DR and VTDR varied by demographic characteristics and geography.

Conclusions and Relevance

US prevalence of diabetes-related eye disease remains high. These updated estimates on the burden and geographic distribution of diabetes-related eye disease can be used to inform the allocation of public health resources and interventions to communities and populations at highest risk.

Association of Diabetic Retinopathy with Chronic Kidney Disease Progression in Latinos with Type 2 Diabetes

Aims

Diabetes remains a leading cause of blindness and kidney failure in the United States. Latinos are at increased risk for type 2 diabetes, and microvascular complications such as diabetic retinopathy (DR) and chronic kidney disease (CKD). We evaluated the association of DR with decline in kidney function in Latinos with type 2 diabetes with or without CKD in a multispecialty clinic.

Methods

This is a retrospective cohort study of 351 self-identified Latino individuals with type 2 diabetes enrolled in the Latino Diabetes Initiative at Joslin Diabetes Center. Baseline demographic factors including age, sex, comorbidities, and laboratory values such as A1c and albuminuria were evaluated as predictors of kidney outcomes. The annualized change in estimated glomerular filtration rate (eGFR) was evaluated with a linear regression model. We used logistic regression to evaluate whether DR was associated with development of rapid progressors (>3 mL/min/y eGFR loss) and 30% change in eGFR per year.

Results

DR was present in 39.2% of the cohort with mild nonproliferative DR (NPDR) in 57.1%, moderate to severe NPDR in 27.8%, and proliferative DR in 15.0%. Those with DR had a longer duration of type 2 diabetes (P<.001), higher albuminuria (P=.003), and lower baseline eGFR (P=.001). We found that individuals with moderate to severe NPDR and proliferative DR had a significant decline in GFR (coefficient -6.32; 95% CI, -11.40 to -1.23) and -7.82 (-14.99 to -0.65), compared with individuals without DR.

Conclusions

The presence of DR is a marker for increased eGFR loss, emphasizing the need for routine retinal examinations as part of comprehensive diabetes care. Individuals with DR should be considered at high risk for GFR loss.

Prevalence of diabetic retinopathy in patients with newly diagnosed type 2 diabetes: A systematic review and meta-analysis

AIMS

Type 2 diabetes mellitus (T2DM) can remain undiagnosed for many years, during which micro- and macro-vascular complications may develop. This study aimed to assess the worldwide prevalence of diabetic retinopathy (DR) in patients with newly diagnosed T2DM.

MATERIALS AND METHODS

We systematically searched electronic databases for relevant studies published from inception to 01 January 2022. Selected studies reported the prevalence of DR among patients with newly diagnosed T2DM, specifying the case definition used. Random-effects meta-analysis was used to derive the pooled prevalence. Subgroup and meta-regression analyses were used to investigate variations in the prevalence estimates in terms of available variables.

RESULTS

Data from 77 studies including 99,847 patients with newly diagnosed T2DM were included from 26 countries. The pooled prevalence of DR among patients with newly diagnosed T2DM was 13.1% (95% CI, 11.1%-15.1%; I²  = 97.0%). DR was higher in clinic-based samples compared with community-based samples (15.0%, 95% CI = 12.4%-17.8% vs. 11.5%, 95% CI = 8.9%-14.5%; p = 0.05; I²  = 97.0%) and was higher in countries in the WHO African 19.2% (95% CI, 14.6%-24.3%; I²  = 76.0%), South-East Asia 15.4% (95% CI, 10.0%-21.6%; I²  = 79.1%), and European 15.0% (95% CI, 11.2%-19.2%; I²  = 82.0%) regions. A higher proportion of female patients was significantly associated with a lower prevalence of DR in patients with newly diagnosed T2DM. We observed that the prevalence of DR in patients with newly diagnosed T2DM has remained unchanged over time.

CONCLUSIONS

Globally, DR is a prevalent complication among patients with newly diagnosed T2DM indicating the importance of establishing effective strategies to promote regular screening for the early diagnosis of T2DM alongside routine ophthalmic assessment at the time of T2DM diagnosis to reduce the burden of vision-threatening retinopathy.

Social Determinants of Health and Impact on Screening, Prevalence, and Management of Diabetic Retinopathy in Adults: A Narrative Review

Diabetic retinal disease (DRD) is the leading cause of blindness among working-aged individuals with diabetes. In the United States, underserved and minority populations are disproportionately affected by diabetic retinopathy and other diabetes-related health outcomes. In this narrative review, we describe racial disparities in the prevalence and screening of diabetic retinopathy, as well as the wide-range of disparities associated with social determinants of health (SDOH), which include socioeconomic status, geography, health-care access, and education.

Sociodemographic variables associated with risk for diabetic retinopathy

BACKGROUND

Several systemic and sociodemographic factors have been associated with the development and progression of diabetic retinopathy (DR). However, there is limited investigation of the potential role sociodemographic factors may play in augmenting systemic risk factors of DR. We hypothesize that age, sex, race, ethnicity, income, and insurance payor have an impact on hemoglobin A1c (HbA1c), body mass index, and systolic blood pressure, and therefore an upstream effect on the development of DR and vision-threatening forms of DR (VTDR).

METHODS

Multivariable analysis of longitudinal electronic health record data at a large academic retina clinic was performed. Sociodemographic factors included race, ethnicity, income, and insurance payor. Systemic risk factors for DR included hemoglobin A1c (HbA1c), systolic blood pressure (SBP), and body mass index (BMI). VTDR was identified from encounter diagnostic codes indicating proliferative retinopathy or diabetic macular edema. Patient-reported primary address zip codes were used to approximate income level, stratified into quartiles.

RESULTS

From 2016 to 2018, 3,470 patients with diabetes totaled 11,437 visits were identified. Black patients had higher HbA1c and SBP compared to White patients. White patients had higher BMI and SBP compared to patients of unknown/other race and greater odds of VTDR than the latter. Patients of Hispanic ethnicity had significantly higher SBP than non-Hispanic patients. Low-income patients had higher BMI and SBP than high-income patients and greater odds of VTDR than the latter. Medicaid recipients had greater odds of VTDR than those with Blue Care Network (BCN) and Blue Cross Blue Shield (BCBS) insurance. Medicaid and Medicare recipients had higher SBP compared to BCBS recipients. Finally, both higher HbA1c and SBP had greater odds of VTDR. There were no differences in odds of VTDR between White and Black patients or between Hispanic and non-Hispanic patients.

CONCLUSION

Significant associations exist between certain sociodemographic factors and well-known risk factors for DR. Income and payor were associated with increased severity of systemic risk factors and presence of VTDR. These results warrant further investigation of how risk factor optimization and disease prevention may be further improved by targeted intervention of these modifiable sociodemographic factors.

Visual Outcomes in Eyes With Neovascular Glaucoma and Anterior Segment Neovascularization Without Glaucoma

PURPOSE

To find predictive factors of neovascular glaucoma (NVG) development in eyes with anterior segment neovascularization without glaucoma (ASNVWG), and poor visual outcomes in eyes that have already developed NVG.

DESIGN

Retrospective, clinical cohort studies.

METHODS

A retrospective chart review was performed on 106 eyes of 94 patients with ASNVWG and 245 eyes of 225 patients with NVG. Measured outcomes included the development of NVG at any time point of the disease for the ASNVWG arm, and a visual acuity of ≤20/200 at 6 months after initial presentation for the NVG arm.

RESULTS

Overall, 25% of ASNVWG eyes progressed to NVG. Progression was associated with retinal vein occlusion (RVO) (P < .01), lower median presenting BCVA (P < .01), and concurrent traction retinal detachments (TRDs) (P = .025). Sixty-eight percent of NVG eyes had a BCVA of ≤20/200 by 6-month follow-up, which was associated with RVO (P = .005), vitreous hemorrhage on presentation (P = .001), and no panretinal photocoagulation (PRP) treatments (P < .001). BCVA >20/200 at 6 months was associated with ≥1 PRP or intravitreal bevacizumab (IVB) treatment within 1 week of presentation or ≥3 PRP or IVB treatments overall (P < .001).

CONCLUSION

RVO, presenting visual acuity, and concurrent TRD are risk factors for NVG in eyes with ASNVWG. In eyes with NVG, RVO and concurrent vitreous hemorrhage are risk factors for ≤20/200 vision at 6 months, whereas treatment with ≥1 PRP or IVB within 1 week of presentation, or ≥3 treatments of PRP or IVB within 6 months are protective.

Racial/Ethnic Disparities in Ophthalmology Clinical Trials Resulting in US Food and Drug Administration Drug Approvals From 2000 to 2020

Importance

Diverse, representative enrollment in pivotal clinical trials is vital to sufficiently power subgroup analyses and ensure equity and validity of trial results.

Objective

To evaluate the racial/ethnic representation, trends, and disparities in clinical trials leading to US Food and Drug Administration (FDA) ophthalmology drug approvals from 2000 to 2020.

Design, Setting, and Participants

This cohort study used data from participants in clinical trials of drugs for neovascular age-related macular degeneration (AMD), open-angle glaucoma (OAG), and expanded indications for diabetic retinopathy (DR) from January 1, 2000, to December 31, 2020. Trial data were sourced from FDA reviews, ClinicalTrials.gov, and relevant linked studies. National expected racial/ethnic proportions were sourced from public National Eye Institute prevalence data as well as published rates scaled using US Census Bureau data.

Main Outcomes and Measures

The primary outcome measures were the distribution of and change over time in the racial/ethnic proportion of participants in clinical trials leading to FDA approval of drugs for AMD, OAG, and DR.

Results

During the 20-year period, 31 clinical trials were identified for 13 medications with 18 410 participants. The distribution of trial participants was different from the expected trial distribution for most approvals with regard to race/ethnicity (12 drugs) and sex (10 drugs). Compared with the first decade (2000-2010), trials conducted in the second decade (2011-2020) showed increases in enrollment of Asian (odds ratio [OR], 2.30; 95% CI, 1.97-2.68; P < .001) and Hispanic or Latinx participants (OR, 1.74; 95% CI, 1.49-2.03; P < .001) for AMD, Asian participants (OR, 2.21; 95% CI, 1.46-3.42; P < .001) for DR, and Black (OR, 1.60; 95% CI, 1.43-1.78; P < .001) and Hispanic or Latinx participants (OR, 10.31; 95% CI, 8.05-13.35; P < .001) for OAG. There was a decrease in Black participants in DR trials (OR, 0.58; 95% CI, 0.42-0.79; P < .001). Based on these trends, the enrollment incidence ratio is expected to worsen by 2050, with overrepresentation of white participants vs underrepresentation of Black and Hispanic or Latinx participants in trials of drugs for AMD (1.08 vs 0.04 vs 0.77), DR (1.83 vs 0.87 vs 0.59), and OAG (1.62 vs 0.90 vs 0.37).

Conclusions and Relevance

In this cohort study, Black, Hispanic or Latinx, and other non-White participants were underrepresented in clinical trials leading to FDA ophthalmology drug approvals compared with the expected disease burden and racial/ethnic distribution in the US. Although there was meaningful improvement from 2000 to 2020, further efforts to increase minority enrollment in clinical trials seem to be warranted.

Cocoa olein glycerolysis with lipase

In this paper we present the valorization of cocoa olein obtained from the acid fat-splitting of soapstocks. The aim is to develop a solvent free process (enzymatically catalyzed) to maximize the production of a final product with high content of monoglycerides (MAG) and diglycerides (DAG). The effect of the enzyme dose, glycerol content, reaction times as well as the modification of the raw material and pressure were studied. The yield of the reaction increased up to 90-95% when using a vacuum of 2-3 mbar at 65 °C, enough to evaporate the water which is generated as a by-product, an enzyme dose of 1% and molar ratio oil:glycerol of 1:2. The highest yield in terms of MAG and DAG production was obtained by starting from a raw material which was rich in free acidity (FFA), rendering oil with 33.4 and 44.2% MAG and DAG, respectively. Short reaction times (6-8 h) were observed compared to previously reported results (24 h).

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.

Status of Renal Replacement Therapy and Peritoneal Dialysis in Mexico

Mexico is struggling to gain a place among developed countries; however, there are many socioeconomic and health problems still waiting for resolution. While Mexico has the twelfth largest economy in the world, a large portion of its population is impoverished. Treatment for end-stage renal disease (377 patients per million population) is determined by the individual's access to resources such as private medical care (approximately 3%) and public sources (Social Security System: approximately 40%; Health Secretariat: approximately 57%). With only 6% of the gross national product spent on healthcare and most treatment providers being public health institutions that are often under economic restrictions, it is not surprising that many Mexican patients do not receive renal replacement therapy. Mexico is still the country with the largest utilization of peritoneal dialysis (PD) in the world, with 18% on automated PD, 56% on continuous ambulatory PD (CAPD), and 26% on hemodialysis. Results of PD (patient morbi-mortality, peritonitis rate, and technique survival) in Mexico are comparable to other countries. However, malnutrition and diabetes mellitus are highly prevalent in Mexican patients on CAPD programs, and these conditions are among the most important risk factors for a poor outcome in our setting.

Distribution of peripheral lesions identified by mydriatic ultra-wide field fundus imaging in diabetic retinopathy

PURPOSE

To analyze the distribution of diabetic retinopathy (DR) lesions in an Indian population using ultra-wide field (UWF) fundus imaging.

METHODS

Seven hundred fifteen subjects (1406 eyes) with diabetic retinopathy in India were enrolled in this multicenter, prospective, observational study using UWF pseudocolor imaging with Optos Daytona Plus (Optos plc, Dunfermline, Scotland, UK). Images were transmitted to Doheny Image Reading Center, Los Angeles, CA, for grading. The ETDRS grid was overlaid on stereographic projections of UWF images, and images were graded independently by 2 masked graders. Lesion distribution was graded as predominantly central (PCL) or predominantly peripheral (PPL) according to previous criteria, considering both lesion number and area. An image was graded as PPL if > 50% of the lesion area was seen in at least one peripheral field as compared with the corresponding ETDRS field. Diabetic retinopathy severity was also assessed based on the International Classification of Diabetic Retinopathy (ICDR) grading scale. The main outcome measures were lesion distribution (PPL versus PCL): overall and within specific fields in eyes with various grades of DR.

RESULTS

Lesion distribution was rated to be PPL in 37% of eyes and PCL in 63% of eyes (P < 0.003). The frequency of a PPL distribution varied significantly across all ICDR severity levels, with frequencies of mild non-proliferative DR (NPDR) (30.9%), moderate NPDR (40.3%), severe NPDR (38.5%) and PDR (34.9%), P = 0.005. When assessing which individual fields were rated to show a PPL distribution, the frequency was greatest in field 4 and least in field 7. For any grade of DR, temporal fields showed the greatest PPL frequency, followed in order by the superior, inferior, and nasal fields (P < 0.001). Only 3.5% of eyes showed PPL distribution in all five peripheral fields.

CONCLUSIONS

One-third of the UWF images showed a PPL distribution in this cohort with the temporal quadrant having the widest distribution of PPL. As the PPL distribution varied significantly between various grades of DR, UWF imaging may prove to be important for screening of referral warranted retinopathy.

Prevalence and risk factors for diabetic retinopathy in a cross-sectional population-based study from rural southern China: Dongguan Eye Study

RESEARCH QUESTION

The current population-based study aimed to investigate the prevalence of diabetic retinopathy (DR) and risk factors among residents over 40 years old in the rural area of Dongguan, southern China.

STUDY DESIGN

The Dongguan Eye Study was a population-based study from September 2011 to February 2012.

SETTING

The area was set in the rural area of Dongguan, southern China.

PARTICIPANTS

Adult rural population aged 40 or older.

INTERVENTION

Participants underwent haematological, physical, ophthalmic examinations and completed a questionnaire regarding lifestyles and systemic medical conditions.

PRIMARY AND SECONDARY OUTCOME MEASURES

The frequency and risk factors of visual impairment and the major vision-threatening eye diseases.

RESULTS

Of the 8952 Han Chinese, 1500 were diagnosed with type 2 diabetes mellitus (T2DM) with an average age of 59.5±11.1 years, and 1310 participants with fundus photography results were analysed. Standardised prevalence rate of DR was 18.2% for all patients with diabetes, 32.8% for the patients with previously diagnosed diabetes and 12.6% for newly diagnosed patients with T2DM. The prevalence rate of male DR was significantly higher than that of female DR (23.0% vs 14.1%, p<0.001). No significant difference was found in age-specific prevalence of DR. In diabetic patients, the prevalence rates of vision-threatening diabetic retinopathy, diabetic macular oedema and clinically significant macular oedema were 2.5%, 2.8% and 0.9%, respectively. Male gender, higher education level, longer duration of diabetes mellitus (DM), higher systolic blood pressure and glycosylated haemoglobin were independent risk factors for DR development in patients with diabetes.

CONCLUSION

A relatively lower prevalence of DR was found among the participants with T2DM in residents over 40 years in the rural area of southern China. Thus, an ophthalmic examination is recommended, especially for individuals with DM and DR risk factors. There is a need to increase awareness and education on DM and DR, especially in subjects with DR risk factors to reduce the incidence of DR and macular oedema.

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.

Diabetic Retinopathy: Focus on Minority Populations

Diabetic retinopathy is a major cause of blindness in the United States. With rise of the epidemic of obesity and diabetes in the USA and around the globe, serious and common diabetic complications are evolving as a major public health problem, particularly among minority populations. These populations are disproportionately affected by diabetes and 2-3 times more likely to develop visually significant complications. In this highly illustrated review article, we discuss the diabetic epidemic, highlighting the biology and the pathophysiologic mechanisms of this disorder on the anatomy of the eye. We also discuss the risk factors and the implications for minority populations. For the health care providers, we provide cutting edge information and imminently relevant information to help evaluate, manage, and know when to refer their patients to a specialist in ophthalmology to quell the tide of the epidemic.

Neovascular Glaucoma: A Retrospective Review from a Tertiary Eye Care Center in Mexico

AIM

To describe the demographic characteristics, ocular comorbidities, and clinical outcomes of patients with neovascular glaucoma (NVG) and to determine the number of patients who returned for a follow-up eye examination.

MATERIALS AND METHODS

We examined the clinical data of patients with NVG, who attended a glaucoma clinic between July 2010 and November 2014. We collected information on the demographic characteristics of the patients to include the level of education, ocular comorbidities, NVG stage, visual acuity, glaucoma medications, intraocular pressure (IOP), and the number of patients who had a follow-up ocular examination at month 1, 3, 6, and 12.

RESULTS

Data from 350 patients (473 eyes) with NVG were collected. We found 91% of the cohort had proliferative diabetic retinopathy (PDR). We found blindness in both or one eye in 14% and 31% of the cohort respectively. Low vision was found in both or one eye in 14% and 32% of the eyes respectively. By 6 months follow-up, only 32% of the patients were seen at our clinic and by 12 months follow-up, this number decreased to 15%. Around 60% of the patients were on no IOP lowering drugs at the first visit. We found 53% of the cohort had an incomplete elementary school education.

CONCLUSION

The results suggest that advanced NVG is a significant ocular problem for patients referred to our clinic with just over half of the patients presenting as blind. We also found that several socioeconomic factors that had an important role in the development of PDR and NVG, specifically, educational status.

CLINICAL SIGNIFICANCE

We described the characteristics of a large cohort of patients with very advanced NVG, reflecting the fact that the strict control of the underlying disease must be the main goal of the Mexican national health system.

HOW TO CITE THIS ARTICLE

Lazcano-Gomez G, Soohoo JR, Lynch A, Bonell LN, Martinez K, Turati M, González-Salinas R, Jimenez-Roman J, Kahook MY. Neovascular Glaucoma: A Retrospective Review from a Tertiary Eye Care Center in Mexico. J Curr Glaucoma Pract 2017;11(2):48-51.

Diabetic Retinopathy Clinical Practice Guidelines: Customized for Iranian Population

PURPOSE

To customize clinical practice guidelines (CPGs) for management of diabetic retinopathy (DR) in the Iranian population.

METHODS

Three DR CPGs (The Royal College of Ophthalmologists 2013, American Academy of Ophthalmology [Preferred Practice Pattern 2012], and Australian Diabetes Society 2008) were selected from the literature using the AGREE tool. Clinical questions were designed and summarized into four tables by the customization team. The components of the clinical questions along with pertinent recommendations extracted from the above-mentioned CPGs; details of the supporting articles and their levels of evidence; clinical recommendations considering clinical benefits, cost and side effects; and revised recommendations based on customization capability (applicability, acceptability, external validity) were recorded in 4 tables, respectively. Customized recommendations were sent to the faculty members of all universities across the country to score the recommendations from 1 to 9.

RESULTS

Agreed recommendations were accepted as the final recommendations while the non-agreed ones were approved after revision. Eventually, 29 customized recommendations under three major categories consisting of screening, diagnosis and treatment of DR were developed along with their sources and levels of evidence.

CONCLUSION

This customized CPGs for management of DR can be used to standardize the referral pathway, diagnosis and treatment of patients with diabetic retinopathy.

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.

Special Action Groups for Policy Change and Infrastructure Support to Foster Healthier Communities on the Arizona-Mexico Border

As part of efforts to help stem the rising tide of diabetes among Hispanic Americans living in Arizona-Mexico border communities, the Border Health Strategic Initiative was launched to foster community-based approaches to diabetes prevention and control. A major thrust of the initiative was establishment of special community action groups (SAGs) to help stimulate policy change and sustain interventions designed to reduce the risk of diabetes and its complications. The SAGs met regularly for more than two years, focusing primarily on policies that encourage development of an infrastructure to support physical activity and healthier nutrition. Through involvement with planning commissions, parks and recreation, and private companies, two community development block grants were obtained to support new walking trails. The SAGs also encouraged elementary schools to improve physical education and change vending machine products, and grocery store owners and managers to allow the demonstration and promotion of healthier foods. These groups, focused on policy and infrastructure change within their communities, may be the glue needed to hold comprehensive community health promotion efforts together.

Diabetic retinopathy

Diabetic retinopathy (DR) is a common complication of diabetes mellitus and is a major cause of vision loss in middle-aged and elderly people. One-third of people with diabetes have DR. Severe stages of DR include proliferative DR, caused by the abnormal growth of new retinal blood vessels, and diabetic macular oedema, in which there is exudation and oedema in the central part of the retina. DR is strongly associated with a prolonged duration of diabetes, hyperglycaemia and hypertension. It is traditionally regarded as a microvascular disease, but retinal neurodegeneration is also involved. Complex interrelated pathophysiological mechanisms triggered by hyperglycaemia underlie the development of DR. These mechanisms include genetic and epigenetic factors, increased production of free radicals, advanced glycosylation end products, inflammatory factors and vascular endothelial growth factor (VEGF). Optimal control of blood glucose and blood pressure in individuals with diabetes remains the cornerstone for preventing the development and arresting the progression of DR. Anti-VEGF therapy is currently indicated for diabetic macular oedema associated with vision loss, whereas laser photocoagulation prevents severe vision loss in eyes with proliferative DR. These measures, together with increasing public awareness and access to regular screening for DR with retinal photography, and the development of new treatments to address early disease stages, will lead to better outcomes and prevent blindness for patients with DR.

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.

Changes in retinal microvascular diameter in patients with diabetes

BACKGROUND AND OBJECTIVES

Diabetic retinopathy is the main microvascular complication in diabetes mellitus and needs to be diagnosed early to prevent severe sight-threatening retinopathy. The purpose of this study was to quantify the retinal microvasculature pattern and analyze the influence of blood glucose level and the duration of diabetes mellitus on the retinal microvasculature.

METHODS

Two groups were analyzed: patients with diabetes (N=26) and patients without diabetes, ie, controls (N=26). A quantitative semiautomated method analyzed retinal microvasculature. The diameters of arterioles and venules were measured. The total numbers of arterioles and venules were counted. The ratio of arteriole diameter to venule diameter was calculated. The retinal microvasculature pattern was related to clinical and biochemical parameters.

RESULTS

Patients with diabetes exhibited larger venule diameters in the upper temporal quadrant of the retina compared to the lower temporal quadrant (124.85±38.03 µm vs 102.92±15.69 µm; P<0.01). Patients with diabetes for 5 or more years had larger venule diameters in the upper temporal quadrant than patients without diabetes (141.62±44.44 vs 112.58±32.11 µm; P<0.05). The degree of venodilation in the upper temporal quadrant was positively correlated with blood glucose level and the estimated duration of diabetes mellitus.

INTERPRETATION AND CONCLUSION

The employed quantitative method demonstrated that patients with diabetes exhibited venule dilation in the upper temporal quadrant, and the duration of diabetes mellitus was positively correlated with blood glucose level. Therefore, the early assessment of retinal microvascular changes is possible prior to the onset of diabetic retinopathy.

High prevalence of diabetic retinopathy and lack of association with integrin α2 gene polymorphisms in patients with type 2 diabetes from Northeastern Mexico

Diabetic retinopathy (DR) is one of the primary causes of blindness in the working age population and is characterized by angiogenesis in the retina. Platelets have been suggested to be involved in the pathogenesis of diabetic microvascular complications. The integrin receptor for collagen/laminin, α2β1, mediates platelet primary adhesion to subendothelial tissues, which is an essential first step in thrombus formation. The gene encoding the α2 subunit of α2β1 integrin has ≥8 polymorphisms, including a BglII/NdeI restriction fragment length polymorphism. To explore the prevalence of DR in a population from Northeastern Mexico, unrelated, hospitalized patients who had received a diagnosis of type 2 diabetes mellitus (DM2) at least 10 years previously were recruited (n=177). DR was diagnosed in a masked manner by independent ophthalmologists using fundus images captured using a non-mydriatic retinal camera. A total of 121 patients with DM2 (68%) had some degree of DR development (DR patients), and 56 patients with DM2 (32%) did not exhibit any sign of DR (No-DR patients). The results showed that after 15 years of DM2 progression, there is an increased risk of DR (P=0.0497; odds ratio, 1.993). In addition, insulin therapy and family history of DM2 were significantly associated with DR. In order to detect a possible association between DR and BglII/NdeI α2 gene polymorphisms, a comparative cross-sectional study between DR and No-DR patients was conducted. The α2 gene was genotyped by polymerase chain reaction-restriction fragment length polymorphism assay. Statistical analysis revealed no association between BglII/NdeI genotypes and the development of DR in this group of patients. In conclusion, the present data indicate a high prevalence of DR in the Mexican population and suggest that the damage in DR is due to other factors, such as the duration of the DM2, and is not linked to BglII/NdeI α2 gene polymorphisms.

Risk factors for proliferative diabetic retinopathy in a Latino American population

PURPOSE

To assess the personal and demographic risk factors for proliferative diabetic retinopathy in Latino Americans in Los Angeles County.

METHODS

In this prospective, non-interventional, cross-sectional case control study, seven hundred and twenty-nine subjects from Los Angeles County University of Southern California Medical Center (LAC + USC), Los Angeles, CA, were enrolled. All patients were recruited prospectively from the LAC + USC Medical Center and affiliated clinics between June 2008 and June 2011. Complete personal data and results from systemic and ophthalmic examinations were collected for all enrolled subjects. Laboratory tests such as glycosylated hemoglobin, creatinine levels, and cholesterol levels were collected prospectively by drawing blood at the time of each patient's clinic visit. The main outcome measures were age, gender, type of diabetes mellitus (DM I or II) duration of diabetes mellitus, history of hypertension, history of insulin use, height, weight, and body mass index, smoking history, glycosylated hemoglobin, creatinine levels, and cholesterol levels.

RESULTS

The mean age of subjects with no diabetic retinopathy was 56.38 years (SD, 10.16), whereas that of patients with proliferative diabetic retinopathy was 57.43 years (SD, 9.63). Parameters that conferred a statistically significant increased risk for proliferative diabetic retinopathy in the multivariate model included gender (men were at higher risk: odds ratio [OR], 4.11; 95% confidence interval [CI], 2.56-6.58), insulin use (OR, 1.85; 95% CI, 1.13-3.03), history of hypertension (OR, 1.64; 95% CI, 1.02-2.63), and duration (>25 years vs. 10-15 years) of diabetes (OR, 22.00; 95% CI, 9.76-49.60).

CONCLUSION

In this case-control study in a Latino population, duration of diabetes and male gender were the strongest risk factor for the development of proliferative diabetic retinopathy followed by insulin use and hypertension. Interestingly, smoking and glycosylated hemoglobin levels did not confer additional significant risk in this cohort.

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.

Native American ancestry is associated with severe diabetic retinopathy in Latinos

PURPOSE

Diabetic retinopathy (DR) is a leading cause of blindness in working age adults. Studies have observed that Latinos have a higher prevalence of DR than whites. The purpose of this study is to test the association between genetic admixture and severe DR in Latinos with type 2 diabetes mellitus (T2DM).

METHODS

We conducted a case-control study using 944 T2DM subjects from the Los Angeles Latino Eye Study. Cases (n = 135) were defined as proliferative or severe nonproliferative DR subjects. Controls (n = 809) were other diabetic subjects in the cohort. Genotyping was performed on the Illumina OmniExpress BeadChip. We estimated genetic ancestry in Latinos using STRUCTURE with the HapMap reference panels. Univariate and multivariate logistic regression analyses were used to test the relationship between the proportions of genetic ancestry and severe DR.

RESULTS

Native American ancestry (NAA) in Latino T2DM subjects is associated significantly with severe DR (P = 0.002). The association remained significant (P = 0.005) after adjusting for age, sex, duration of diabetes, hemoglobin A1c, body mass index, systolic blood pressure, education, and income. We also validated the NAA estimates in Latinos using ADMIXTURE with the 1000 Genomes Project reference panels and obtained consistent results.

CONCLUSIONS

Our results demonstrate for the first time to our knowledge that NAA is a significant risk factor for severe DR in Latinos.

Diabetic retinopathy in patients with newly diagnosed type 2 diabetes mellitus in Jordan: prevalence and associated factors

BACKGROUND

To determine the prevalence of diabetic retinopathy (DR) in patients with newly diagnosed type 2 diabetes mellitus (T2DM) in Jordan, as well as the factors associated with DR.

METHODS

A cross-sectional study was conducted among 127 consecutive newly diagnosed (within the past 6 months) patients with T2DM attending one of two diabetic care centers. Complete ocular examinations were performed by an ophthalmologist and relevant data were collected. A fundus examination was performed using slit lamp indirect ophthalmoscopy after pupillary dilation with 1% tropicamide drops, with DR defined and classified according to the scale developed by the Global Diabetic Retinopathy Project Group.

RESULTS

Of all the patients examined, 7.9% had DR. Of those with DR, 40% already had clinically significant macular edema necessitating laser photocoagulation or intravitreal injections. Multivariate analysis revealed that age and HbA1c were significantly associated with DR. The odds of DR increased by 11% for each 1 year increase in age (odds ratio [OR] 1.11; 95% confidence interval [CI] 1.02-1.20). For each 1% increase in HbA1c, the odds of DR increased by 43% (OR 1.43; 95% CI 1.09-1.88).

CONCLUSIONS

Fewer than one-tenth of newly diagnosed Jordanian patients with T2DM had DR, but more than one-third of these patients had significant maculopathy. Therefore, early screening is strongly recommended for all newly diagnosed T2DM patients. Increased age and HbA1c values are associated with increased odds of DR. A study with a larger sample size is needed to elucidate the risk factors for DR in newly diagnosed T2DM.

Prevalence of diabetic retinopathy in Type 2 diabetes in developing and developed countries

BACKGROUND

As the global prevalence of diabetes increases, so will the numbers of people with diabetic retinopathy. Our review aimed to provide a comprehensive picture of available studies of diabetic retinopathy and how prevalence varies around the developed and developing world.

METHODS

A detailed literature search using PubMed was undertaken. The following search term was used: 'diabetic retinopathy AND prevalence'. The titles and abstracts of all publications identified by the search were reviewed and 492 studies were retrieved. Inclusion and exclusion criteria were applied.

RESULTS

A total of 72 articles from 33 countries were included. There were only 26 population-based studies using fundus photography (12 in developing countries), of which only 16 (eight in developing countries) were published since 2000. Prevalence estimates varied from as low as 10% to as high as 61% in persons with known diabetes and from 1.5 to 31% in newly diagnosed diabetes. Across all the studies, the median (interquartile range) prevalence of any diabetic retinopathy in known diabetes was 27.9% (22-37%) and 10.5% (6-16%) in newly diagnosed diabetes. Prevalence of diabetic retinopathy was higher in developing countries.

CONCLUSION

Significant gaps exist in that reliable population-based data from developing nations and indigenous populations in particular are lacking. Major differences in study characteristics and methodologies make comparisons very difficult. More research is required and study methodologies must be better standardized. This will provide important information for prevention and treatment strategies.

Evaluation for fasting and 2-hour glucose and HbA1c for diagnosing diabetes based on prevalence of retinopathy in a Chinese population

Background

The glycemic thresholds for diabetes diagnosis have long been at the forefront of discussion. However, no information about glycemic cutoff points has been made available for the Chinese population. The aim of the present study was to examine the association of fasting plasma glucose (FPG), 2-h plasma glucose (2-h PG) and HbA₁c levels with diabetic retinopathy (DR) and determine the associated cutoff levels in a Chinese population.

Methodology and Principal Findings

In a cross-sectional population-based sample of 2551 Chinese (representing a population of 1,660,500 in a Beijing district) between 18–79 years of age, the three glycemic measures were measured in a 75 g oral glucose tolerance test, and DR was assessed by two 45° color digital retinal images. The prevalence of DR increased in the ninth decile of each variable, corresponding to an FPG of ≥7.2 mmol/l, a 2-h PG of ≥10.7 mmol/l, and HbA₁c of ≥6.4%, according to the Joinpoint regression method. After excluding individuals receiving antihyperglycemic medication, the prevalence significantly increased at an FPG of ≥6.8 mmol/l, a 2-h PG of ≥12.0 mmol/l, and HbA₁c of ≥6.7%. The area under the ROC curve for all three measures showed no significant differences for detecting DR. After excluding individuals receiving antihyperglycemic medication, the three measures also showed no significant differences.

Conclusions and Significance

A significant increase in retinopathy prevalence occurs among individuals with FPG ≥7.2 mmol/l, 2-h PG ≥10.5 mmol/and HbA₁c ≥6.4%; and measuring FPG or HbA₁c are equally reliable methods as measuring 2-h PG for the diagnosis of diabetes in the Chinese population.

Prevalence and risk factors of diabetic retinopathy in migrant Indians in an urbanized society in Asia: the Singapore Indian eye study

PURPOSE

To describe the prevalence of and risk factors for diabetic retinopathy (DR) in Indian persons living in a newly urbanized society in Asia.

DESIGN

Population-based study.

PARTICIPANTS

Ethnic Indians aged ≥40 years living in Singapore.

METHODS

The Singapore Indian Eye Study was conducted between 2007 and 2009. All participants underwent an extensive ophthalmic examination, including retinal photographs obtained after pupil dilation. These images were graded for the presence and severity of DR using the modified Airlie House classification system. Diabetes was defined as hemoglobin A1c level of ≥6.5%, use of diabetic medication, or a physician diagnosis of diabetes. Risk factors were measured using questionnaires, clinical assessments, or laboratory tests.

MAIN OUTCOME MEASURES

Any DR, diabetic macular edema (DME), or vision-threatening DR (VTDR).

RESULTS

Among the 3400 participants, the age-standardized prevalence was 33.6% (95% confidence interval [CI], 31.4-35.8) for diabetes and 10.5% (95% CI, 9.3-11.8) for DR. Among those with diabetes only, the age-standardized prevalence was 30.4% (95% CI, 26.5-34.8) for any DR, 7.2% (95% CI, 5.3-9.7) for DME, and 7.1% (95% CI, 5.4-9.5) for VTDR. In multivariate analysis, independent risk factors for any DR were younger age (odds ratio [OR], 0.98; 95% CI, 0.96-1.00, per year increase), longer diabetes duration (OR, 1.09; 95% CI, 1.07-1.11 per year increase), higher hemoglobin A1c (OR, 1.23; 95% CI, 1.13-1.34 per percent increase), higher systolic blood pressure (OR, 1.01; 95% CI, 1.00-1.02 per 1-mmHg increase), lower diastolic blood pressure (OR, 0.97; 95% CI, 0.96-0.99 per 1-mmHg increase), history of previous stroke (OR, 2.16; 95% CI, 1.12-4.16), and insulin treatment (OR, 2.99; 95% CI, 1.84-4.87). Similar independent risk factors, except for blood pressure, were found for VTDR. Additionally, persons with lower income and living in smaller houses were associated with VTDR.

CONCLUSIONS

One in 3 migrant Indians living in newly urbanized Asian societies have diabetes and 1 in 10 has DR. This is similar to rates reported in Western populations and significantly higher than those reported in India.

Diabetic nephropathy among Mexican Americans

The incidence of diabetic nephropathy (DN) is growing rapidly worldwide as a consequence of the rising prevalence of Type 2 diabetes mellitus (T2DM). Among U.S. ethnic groups, Mexican Americans have a disproportionately high incidence and prevalence of DN and associated end-stage renal disease (ESRD). In communities bordering Mexico, as many as 90% of Mexican American patients with ESRD also suffer from T2DM compared to only 50% of non-Hispanic Whites (NHW). Both socio-economic factors and genetic predisposition appear to have a strong influence on this association. In addition, certain pathogenetic and clinical features of T2DM and DN are different in Mexican Americans compared to NHW, raising questions as to whether the diagnostic and treatment strategies that are standard practice in the NHW patient population may not be applicable in Mexican Americans. This article reviews the epidemiology of DN in Mexican Americans, describes the pathophysiology and associated risk factors, and identifies gaps in our knowledge and understanding that needs to be addressed by future investigations.

Refractive error and visual function difficulty in a Latino population

OBJECTIVE

To assess the association of correction of myopia, hyperopia, and astigmatism with self-reported near and distance visual function.

DESIGN

Population based, cross-sectional study.

PARTICIPANTS

A random sample of 4272 Latinos older than 40 years of age from Arizona with both ophthalmic examination and questionnaire data, including answers to the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25).

METHODS

Cases of refractive error (RE) were defined as subjects who met at least 1 of the following criteria in both eyes: myopia, sphere -0.5 diopters (D) or less; hyperopia, sphere 1.0 D or more; or astigmatism, cylinder 0.75 D or more. Uncorrected refractive error (URE) was defined as having RE and achieving 2 lines or more of improvement in visual acuity in both eyes after refraction. The association between RE category and near and distance vision difficulty (as measured by the NEI VFQ-25 near and distance vision subscores) was modeled with ordinal logistic regression, adjusting for age, gender, diabetes, hypertension, income, education, and acculturation.

MAIN OUTCOME MEASURES

Association between RE correction and near and distance vision difficulty by type of RE (myopia, hyperopia, and astigmatism).

RESULTS

Of 4272 participants, 54% had RE. Forty-eight percent of these had myopia, 41% had hyperopia, and 11% had astigmatism. Fourteen percent of myopes, 21% of hyperopes, and 22% of astigmatics had URE. Subjects with myopia, astigmatism, and hyperopia were significantly more likely to report more distance vision difficulty than subjects without RE, regardless of whether they had correction (odds ratios [ORs], 1.7-3.7; P<0.005 for all). Subjects with corrected myopia reported less near vision difficulty than subjects without RE (OR, 0.8; 95% confidence interval [CI], 0.7-0.9). Subjects with uncorrected hyperopia and uncorrected astigmatism reported more near vision difficulty than those without RE (OR, 1.6; 95% CI, 1.2-2.2; and OR, 1.7; 95% CI, 1.0-3.0, respectively). Self-reported distance and near visual function scores were sensitive to nonvision variables, namely, age, gender, diabetes, high blood pressure, acculturation score, income, and education.

CONCLUSIONS

In this population, correction of any type of RE is not entirely sufficient to restore distance visual function to the level of those without RE. More research is necessary to determine the reasons for this shortcoming.

Prevalence of diabetic retinopathy in various ethnic groups: a worldwide perspective

The alarming rise in diabetes prevalence is a global public health and economic problem. Diabetic retinopathy is the most common complication of diabetes and the leading cause of blindness among working-age populations in the Western world. Screening and prompt treatment of diabetic retinopathy are not top priorities in many regions of the world, because the impacts of other causes of preventable blindness remain an issue. Ethnicity is a complex, independent risk factor for diabetic retinopathy. Observations from white populations cannot be extrapolated fully to other ethnic groups. The prevalence of diabetic retinopathy, sight-threatening diabetic retinopathy, and clinically significant macular edema are higher in people of South Asian, African, Latin American, and indigenous tribal descent compared to the white population. Although all ethnic groups are susceptible to the established risk factors of diabetic retinopathy-such as length of exposure and severity of hyperglycemia, hypertension, and hyperlipidemia-ethnic-specific risk factors also may influence these rates. Such risk factors may include differential susceptibility to conventional risk factors, insulin resistance, differences in anthropometric measurements, truncal obesity, urbanization, variations in access to healthcare systems, genetic susceptibility, and epigenetics. The rates of nonproliferative diabetic retinopathy appear to be declining in the United States, supporting the observation that better medical management of diabetes and prompt treatment of sight-threatening diabetic retinopathy substantially improve the long-term diabetic retinopathy incidence; studies from other parts of the world are limited and do not mirror this finding, however. We examine the ethnicity and region-based prevalence of diabetic retinopathy around the world and highlight the need to reinforce ethnicity-based screening and treatment thresholds in diabetic retinopathy.

Prevalence and risk factors for diabetic microvascular complications in newly diagnosed type II diabetes mellitus. Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN-DREAMS, report 27)

PURPOSE

The aims of this study were to report the prevalence of various microvascular complications and to identify the various clinical and biochemical characteristics related to these complications in subjects with newly diagnosed type II diabetes.

METHODS

Of the 5999 subjects enumerated, 1414 subjects with diabetes (both known and newly diagnosed) were analyzed for the study. Among the diabetic subjects, 248 (17.5%) were newly diagnosed with diabetes and the remaining had history of diabetes. All subjects underwent a detailed standard evaluation to detect diabetic retinopathy (fundus photography), neuropathy (vibration pressure threshold), and nephropathy (microalbuminuria).

RESULTS

The prevalence of any form of microvascular complication was 30.2% (95% confidence interval [CI]=24.5-35.9). The prevalence of diabetic retinopathy was 4.8%, and that of diabetic nephropathy and neuropathy was 10.5%. The risk factors for developing any form of microvascular complication were increasing age (odds ratio [OR]=1.07, 95% CI=1.04-1.11, P<.0001), increasing systolic blood pressure (OR=1.03, 95% CI=1.01-1.06, P=.001), and increasing hemoglobin (OR=1.39, 95% CI=1.09-1.79, P=.011). The risk factors for diabetic retinopathy and diabetic nephropathy were increasing systolic blood pressure (OR=1.06 [P=.001] for retinopathy and OR=1.04 [P=.012] for nephropathy) and increasing hemoglobin (OR=2.20 [P=.007] for retinopathy and OR=1.57 [P=.023] for nephropathy). The risk factor for diabetic neuropathy was increasing age (OR=1.12, P<.0001).

CONCLUSIONS

Nearly one third of the newly diagnosed type II diabetes subjects had some form of microvascular complication; nephropathy, and neuropathy being commoner than retinopathy.

Global prevalence and major risk factors of diabetic retinopathy

OBJECTIVE

To examine the global prevalence and major risk factors for diabetic retinopathy (DR) and vision-threatening diabetic retinopathy (VTDR) among people with diabetes.

RESEARCH DESIGN AND METHODS

A pooled analysis using individual participant data from population-based studies around the world was performed. A systematic literature review was conducted to identify all population-based studies in general populations or individuals with diabetes who had ascertained DR from retinal photographs. Studies provided data for DR end points, including any DR, proliferative DR, diabetic macular edema, and VTDR, and also major systemic risk factors. Pooled prevalence estimates were directly age-standardized to the 2010 World Diabetes Population aged 20-79 years.

RESULTS

A total of 35 studies (1980-2008) provided data from 22,896 individuals with diabetes. The overall prevalence was 34.6% (95% CI 34.5-34.8) for any DR, 6.96% (6.87-7.04) for proliferative DR, 6.81% (6.74-6.89) for diabetic macular edema, and 10.2% (10.1-10.3) for VTDR. All DR prevalence end points increased with diabetes duration, hemoglobin A(1c), and blood pressure levels and were higher in people with type 1 compared with type 2 diabetes.

CONCLUSIONS

There are approximately 93 million people with DR, 17 million with proliferative DR, 21 million with diabetic macular edema, and 28 million with VTDR worldwide. Longer diabetes duration and poorer glycemic and blood pressure control are strongly associated with DR. These data highlight the substantial worldwide public health burden of DR and the importance of modifiable risk factors in its occurrence. This study is limited by data pooled from studies at different time points, with different methodologies and population characteristics.

Systemic soluble tumor necrosis factor receptors 1 and 2 are associated with severity of diabetic retinopathy in Hispanics

PURPOSE

To investigate the associations of serum amyloid A (SAA) protein and soluble tumor necrosis factor receptors 1 and 2 (sTNF-R1 and sTNF-R2) with diabetic retinopathy (DR) in Hispanics.

DESIGN

Prospective, nonrandomized, cross-sectional, family-based observational cohort study.

PARTICIPANTS

A total of 473 Hispanic type II diabetic subjects in families ascertained via proband with DR.

METHODS

Levels of SAA, sTNF-R1, and sTNF-R2 were measured with enzyme-linked immunosorbent assay. Diabetic retinopathy was assessed by fundus photography and graded using modified Airlie House classification.

MAIN OUTCOME MEASURES

Levels of SAA, sTNF-R1, and sTNF-R2 to severity of DR with and without covariates.

RESULTS

A direct association of sTNF-R1 (2.37±0.13, 2.15±0.09, 3.09±0.24, 3.25±0.46, 5.02±0.61 ng/ml; P < 0.0001) and sTNF-R2 (6.04±0.20, 6.25±0.52, 7.96±0.70, 8.14±1.13, 14.83±1.68 ng/ml; P < 0.0001) was found for no DR, mild nonproliferative DR (NPDR), moderate NPDR, severe NPDR, and proliferative DR, respectively. These associations remained significant after adjusting for age, gender, body mass index, glycosylated hemoglobin, diabetes duration, systolic blood pressure, and serum creatinine (P < 0.0001 for sTNF-R1 and P=0.0004 for sTNF-R2). A similar pattern was observed when we adjusted for urinary albumin:creatinine ratio in place of serum creatinine (P=0.005 for sTNF-R1 and P=0.02 for sTNF-R2).

CONCLUSIONS

Levels of sTNF-R1 and sTNF-R2 are highly correlated with the severity of DR, suggesting that inflammation and insulin resistance may play a critical role in the development of DR. These may be useful biomarkers for DR, aiding in etiologic studies and possibly identifying at-risk patients for active intervention.