Risk factors for diabetic retinopathy in self-reported rural population with diabetes

Assessing the importance of risk factors for diabetic retinopathy in patients with type 2 diabetes mellitus: Results from the classification and regression tree models

BACKGROUND

Diabetic retinopathy (DR) is one of the serious complications of diabetes mellitus (DM). Many studies have identified the risk factors associated with DR, but there is not much evidence on the importance of these factors for DR. This study aimed to investigate the associated factors for patients with type 2 DM (T2DM) and calculate the importance of the identified factors.

MATERIALS AND METHODS

Using probability proportionate to size sampling method in this community-based cross-sectional study, 22 community health service centers were selected from 10 administrative districts in Shenzhen, China. Approximately 60 T2DM patients were recruited from each center. The participants completed a structural questionnaire, had their venous blood collected, and underwent medical examinations and fundus photography. Logistic regression models were used to identify the risk factors of DR. The classification and regression tree (CART) model was used to calculate the importance of the identified risk factors.

RESULTS

This study recruited 1097 T2DM patients, 266 of whom were identified as having DR, yielding a prevalence rate of 24.3% (95% confidence interval [CI]: 21.7%-26.9%). Results showed that a longer duration of DM, indoor-type lifestyle, and higher levels of hemoglobin A1c (HbA1c) or urea increased the risk of DR. Patients with HbA1c values ≥7% were about 2.45 times (odds ratio: 2.45; 95% CI: 1.83-3.29) more likely to have DR than their counterparts. The CART model found that the values of variable importance for HbA1c, DM duration, lifestyle (i.e., indoor type), and urea were 48%, 37%, 10%, and 4%, respectively.

CONCLUSION

The prevalence of DR is high for T2DM patients who receive DM health management services from the primary healthcare system. HbA1c is the most important risk factor for DR. Integration of DR screening and HbA1c testing into the healthcare services for T2DM to reduce vision impairment and blindness is urgently warranted.

Genomic profile of diabetic retinopathy in a north indian cohort

BACKGROUND

Diabetic Retinopathy (DR) is one of the major microvascular complications of diabetes. Being a complex disease, it is important to delineate the genetic and environmental factors that influence the susceptibility to DR in a population. Therefore, the present study was designed to investigate the role of genetic and lifestyle risk factors associated with DR susceptibility in a North-Indian population.

METHODS

A total of 848 subjects were enrolled, comprising of DR cases (n = 414) and healthy controls (n = 434). The Sequenom MassARRAY technology was used to perform target genome analysis of 111 SNPs across 57 candidate genes and 14 intergenic region SNPs that are involved in the metabolic pathways associated with type 2 diabetes (T2D) and DR. Allele, genotype and haplotype frequencies were determined and compared among cases and controls. Logistic regression models were used to determine genotype-phenotype and phenotype-phenotype correlations.

RESULTS

The strongest association was observed with TCF7L2 rs12255372 T allele [p < 0.0001; odds ratio (OR) = 1.81 (1.44-2.27)] and rs11196205 C allele [p < 0.0008; OR = 1.62 (1.32-1.99)]. Genotype-phenotype and phenotype-phenotype correlations were found in the present study.

CONCLUSION

Our study provides strong evidence of association between the TCF7L2 variants and DR susceptibility.

Machine Learning-Based Diagnosis and Ranking of Risk Factors for Diabetic Retinopathy in Population-Based Studies from South India

This paper discusses the importance of investigating DR using machine learning and a computational method to rank DR risk factors by importance using different machine learning models. The dataset was collected from four large population-based studies conducted in India between 2001 and 2010 on the prevalence of DR and its risk factors. We deployed different machine learning models on the dataset to rank the importance of the variables (risk factors). The study uses a t-test and Shapely additive explanations (SHAP) to rank the risk factors. Then, it uses five machine learning models (K-Nearest Neighbor, Decision Tree, Support Vector Machines, Logistic Regression, and Naive Bayes) to identify the unimportant risk factors based on the area under the curve criterion to predict DR. To determine the overall significance of risk variables, a weighted average of each classifier's importance is used. The ranking of risk variables is provided to machine learning models. To construct a model for DR prediction, the combination of risk factors with the highest AUC is chosen. The results show that the risk factors glycosylated hemoglobin and systolic blood pressure were present in the top three risk factors for DR in all five machine learning models when the t-test was used for ranking. Furthermore, the risk factors, namely, systolic blood pressure and history of hypertension, were present in the top five risk factors for DR in all the machine learning models when SHAP was used for ranking. Finally, when an ensemble of the five machine learning models was employed, independently with both the t-test and SHAP, systolic blood pressure and diabetes mellitus duration were present in the top four risk factors for diabetic retinopathy. Decision Tree and K-Nearest Neighbor resulted in the highest AUCs of 0.79 (t-test) and 0.77 (SHAP). Moreover, K-Nearest Neighbor predicted DR with 82.6% (t-test) and 78.3% (SHAP) accuracy.

Risk factors affecting cataract surgery outcome: The Malaysian cataract surgery registry

This is a 5 years multicentre database study that recruited subjects from the Malaysian Ministry of Health Cataract Surgery Registry (MOH CSR), aimed to determine risk factors that affect cataract surgery visual outcome and evaluates post-cataract surgery vision. All age-related cataract surgeries with primary intraocular lens (IOL) implantation were included. Cases with secondary cataract, previous ocular surgeries and incomplete data were excluded. A total of 131425 cases were included in the study. Amongst all types of cataract surgery, 92.9% attained post-operative best-corrected visual acuity better than 6/18 and the outcome improved to 97.1% when ocular comorbidities were excluded. Factors with Odds Ratio (OR) >1.5 associated with an impaired visual outcome included: elderly patients of 80 years old and above; systemic disease such as renal failure; ocular co-morbidities; pre-operative vision worse than 6/60; general anaesthesia, retrobulbar anaesthesia or subconjunctival anaesthesia; extracapsular cataract extraction (ECCE), intracapsular cataract extraction (ICCE), anterior chamber intraocular lens (ACIOL) implantation or combined cataract surgery; the presence of intra- and post-operative complications. In conclusion, a good visual outcome was achieved after cataract surgery in most cases. This large multicentre study provides information about risk factors for poor visual outcome post-cataract surgery and may serve as a basis for evidence-based guidelines.

Alterations of Ocular Surface Parameters in Type 2 Diabetic Patients

OBJECTIVE

The purpose of the study was to evaluate the changes in the ocular surface parameters of type 2 diabetic patients.

METHODS

This study is a cross-sectional observational study. It included 76 eyes of 38 patients with type 2 diabetes and 183 eyes of 92 non-diabetic controls. The diabetic subjects were divided into two groups based on diabetic duration. Ocular surface parameters were assessed for all participants.

RESULTS

The diabetic group had a significantly thinner lipid layer thickness (LLT) (p = 0.008) than non-diabetic controls. LLT in the subgroup with diabetic duration ≥10 years was significantly thinner than that in the subgroup with diabetic duration <10 years (p = 0.006). Multivariate linear regression analysis showed that LLT was associated with the duration of diabetes (β = -1.497, p = 0.009) and Schirmer I test (SIT) score (β = 0.852, p = 0.04) in diabetic. Diabetic duration was significantly negatively associated with LLT (β = -0.062, p = 0.004) and significantly positively associated with ocular surface disease index (OSDI) (β = 0.087, p = 0.039).

CONCLUSION

Diabetic patients exhibit significantly reduced LLT and this trend becomes more pronounced with increased duration of diabetes.

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.

Sex differences in the association of prediabetes and type 2 diabetes with microvascular complications and function: The Maastricht Study

BACKGROUND

Women with type 2 diabetes are disproportionally affected by macrovascular complications; we here investigated whether this is also the case for microvascular complications and retinal microvascular measures.

METHODS

In a population-based cohort study of individuals aged 40-75 years (n = 3410; 49% women, 29% type 2 diabetes (oversampled by design)), we estimated sex-specific associations, and differences therein, of (pre)diabetes (reference: normal glucose metabolism), and of continuous measures of glycemia with microvascular complications and retinal measures (nephropathy, sensory neuropathy, and retinal arteriolar and venular diameters and dilatation). Sex differences were analyzed using regression models with interaction terms (i.e. sex-by- (pre)diabetes and sex-by-glycemia) and were adjusted for potential confounders.

RESULTS

Men with type 2 diabetes (but not those with prediabetes) compared to men with normal glucose metabolism, (and men with higher levels of glycemia), had significantly higher prevalences of nephropathy (odds ratio: 1.58 95% CI (1.01;2.46)) and sensory neuropathy (odds ratio: 2.46 (1.67;3.63)), larger retinal arteriolar diameters (difference: 4.29 µm (1.22;7.36)) and less retinal arteriolar dilatation (difference: - 0.74% (- 1.22; - 0.25)). In women, these associations were numerically in the same direction, but generally not statistically significant (odds ratios: 1.71 (0.90;3.25) and 1.22 (0.75;1.98); differences: 0.29 µm (- 3.50;4.07) and: - 0.52% (- 1.11;0.08), respectively). Interaction analyses revealed no consistent pattern of sex differences in the associations of either prediabetes or type 2 diabetes or glycemia with microvascular complications or retinal measures. The prevalence of advanced-stage complications was too low for evaluation.

CONCLUSIONS

Our findings show that women with type 2 diabetes are not disproportionately affected by early microvascular complications.

Sex-Gender Differences in Diabetic Retinopathy

Diabetic retinopathy (DR) is one of the main causes of visual loss in individuals aged 20–64 years old. The aim of this study was to investigate, in a multicenter retrospective cross-sectional study, sex-gender difference in DR in a large sample of type 2 diabetic patients (T2DM). 20,611 T2DM regularly attending the units for the last three years were classified as having: (a) No DR (NDR), (b) nonproliferative DR (NPDR), or (c) preproliferative/proliferative DR (PPDR). DR of all grades was present in 4294 T2DM (20.8%), with a significant higher prevalence in men as compared to women (22.0% vs. 19.3% p < 0.0001). Among DR patients, both NPDR and PPDR were significantly more prevalent in men vs. women (p = 0.001 and p = 0.0016, respectively). Women had similar age and BMI, but longer diabetes duration, worse glycemic metabolic control, and more prevalence of hypertension and chronic renal failure (CRF) of any grade vs. men. No significant differences between sexes were evident in term of drug therapy for diabetes and associate pathologies. Conclusions: In this large sample of T2DM, men show higher prevalence of DR vs. women, in spite of less represented risk factors, suggesting that male sex per se might be a risk factor for DR development.

Hypertension, blood pressure control and diabetic retinopathy in a large population-based study

Background

Clinical trials have shown beneficial effects of blood pressure (BP) control in reducing the risk of diabetic retinopathy (DR). However, association between BP control and DR in population-based studies is not clear. We aimed to examine the association of hypertension and BP control with DR.

Methods

We analysed data from a population-based cross-sectional study of Chinese, Malay and Indians adults with diabetes and hypertension (2004–2011, n = 2189, aged 40–80 years) in Singapore. DR severity was assessed from retinal photographs and graded for any- and vision-threatening DR (VTDR) using the modified Airlie House classification. Hypertension status was classified into (1) good control: on treatment (SBP < 130 and DBP < 80 mm Hg), (2) moderate control: on treatment, with BP levels other than group 1 and 3, (3) poor control: on treatment (SBP ≥140 and DBP ≥ 90 mm Hg), (4) untreated hypertension, any BP level. SBP, DBP and pulse pressure (PP) were analyzed as categories and as continuous variables. The association between BP and DR was assessed using multivariable logistic regression models.

Results

The prevalence of any-DR and VTDR in the study population was 33.8% and 9.0% respectively. Both poorly controlled and untreated hypertension were significantly associated with any-DR with odds ratio (OR) (95% confidence interval [CI]) of 1.97 (1.39–2.83), and 2.01 [1.34–3.05]. Among BP components, SBP and PP were associated with both any-DR and VTDR with OR (95% CI) of 1.45 (1.28–1.65) and 1.61 (1.41–1.84) for any-DR, and 1.44 (1.19–1.76) and 1.67 (1.37–2.06) for VTDR.

Conclusion

In a population-based sample of Asian adults with diabetes and hypertension, treated but poorly controlled as well as untreated hypertension were significantly associated with any-DR. Among the BP components, higher SBP and PP levels were associated with both any-DR and VTDR. Further longitudinal studies are necessary to confirm our findings.

Effectiveness of Teleretinal Imaging-Based Hospital Referral Compared With Universal Referral in Identifying Diabetic Retinopathy: A Cluster Randomized Clinical Trial

Question

Does screening for diabetic retinopathy by teleretinal imaging in physician offices in India lead to higher adherence to eye hospital referral and a greater yield of diabetic retinopathy cases compared with a strategy of referral of all eligible patients with diabetes?

Findings

In a cluster randomized clinical trial of 801 patients with diabetes, proportionately more patients in the teleretinal group attended the hospital eye examination and had confirmed diabetic retinopathy compared with the control group.

Meaning

The results suggest that, in the Indian setting, teleretinal screening is an effective approach for identifying diabetic retinopathy.

Importance

Studies in high-income countries provide limited evidence from randomized clinical trials on the benefits of teleretinal screening to identify diabetic retinopathy (DR).

Objective

To evaluate the effectiveness of teleretinal-screening hospital referral (TR) compared with universal hospital referral (UR) in people with diabetes.

Design, Setting, and Participants

A cluster randomized clinical trial of 8 diabetes clinics within 10 km from Aravind Eye Hospital (AEH), Madurai, India, was conducted. Participants included 801 patients older than 50 years. The study was conducted from May 21, 2014, to February 7, 2015; data analysis was performed from March 12 to June 16, 2015.

Interventions

In the TR cohort, nonmydriatic, 3-field, 45° retinal images were remotely graded by a retinal specialist and patients with DR, probable DR, or ungradable images were referred to AEH for a retinal examination. In the UR cohort, all patients were referred for a retinal examination at AEH.

Main Outcomes and Measures

Hospital-diagnosed DR.

Results

Of the 801 participants, 401 were women (50.1%) (mean [SD] age, 60.0 [7.3] years); mean diabetes duration was 8.6 (6.6) years. In the TR cohort, 96 of 398 patients (24.1%) who underwent teleretinal imaging were referred with probable DR (53 [13.3%]) or nongradable images (43 [10.8%]). Hospital attendance at AEH was proportionately higher with TR (54 of 96 referred [56.3%]) compared with UR (150 of 400 referred [37.5%]). The intention-to-treat analysis based on all patients eligible for referral in each arm showed that proportionately more patients with TR (36 of 96 [37.5]%) were diagnosed with DR compared with UR (50 of 400 [12.5%]) (unadjusted risk ratio [RR], 3.00; 95% CI, 2.01-4.48). These results were little changed by inclusion of covariates (RR, 2.72; 95% CI, 1.90-3.91). The RR was lower in the per-protocol analysis based on all patients who adhered to referral (covariate-adjusted RR, 1.75; 95% CI, 1.12-2.74). Diagnoses of DR were predominantly mild or moderate nonproliferative DR (36 in TR and 43 in UR). In the UR arm, there were 4 cases of severe nonproliferative DR and 2 cases of proliferative DR. Age (RR, 0.98; 95% CI, 0.95-0.99), female sex (RR, 0.79; 95% CI, 0.64-0.98), and hypertension diagnosis (RR, 0.81; 95% CI, 0.68-0.95) were factors associated with lower attendance. Those with higher secondary educational level or more were twice as likely to attend (RR, 2.00; 95% CI, 1.32-3.03).

Conclusions and Relevance

The proportionate yield of DR cases was higher in the TR arm, confirming the potential benefit, at least in the setting of eye hospitals in India, of a targeted referral approach using teleretinal screening to identify patients with DR.

Trial Registration

ClinicalTrials.gov identifier: NCT02085681

Clinical Predictors of Diabetic Retinopathy Progression; A Systematic Review

OBJECTIVE

This study was conducted to discuss the clinical value of published Diabetic Retinopathy Progression determinants.

METHODS

The data for systematic review was collected from the published studies through PubMed and Medline. These studies discussed the clinical predictors of Diabetic Retinopathy (DR) progression. The common keywords used were diabetic Retinopathy, diabetes mellitus, systolic blood pressure, hemoglobin, and albuminuria.

RESULTS

Diabetic Retinopathy is one of the common causes of irreversible visual impairment among adults. Poor glycemic control, systemic hypertension, diabetes duration, dyslipidemia, and microalbuminuria are the major risk factors for the development and progression of diabetic retinopathy. Recently, increased aortic stiffness has been identified as a prognostic marker of diabetic retinopathy and peripheral neuropathy.

CONCLUSION

Certain groups of diabetic individuals are at higher risk to have progressive diabetic retinopathy and eventually visual impairment. Clinical determinants and predictors are considered as prognostic markers and could help physicians to develop an effective risk-based screening program for this condition.

Targeting epigenetic modifications as a potential therapeutic option for diabetic retinopathy

Diabetic retinopathy (DR) is the leading cause of visual impairment in adults of working age (20-65 years) in developed countries. The metabolic memory phenomena (persistent effect of a glycemic insult even after retrieved) associated with it has increased the risk of developing the complication even after the termination of the glycemic insult. Hence, the need for finding early diagnosis and treatment options has been of great concern. Epigenetic modifications which generally occur during the beginning stages of the disease are responsible for the metabolic memory effect. Therefore, the therapy based on the reversal of the associated epigenetic mechanism can bring new insight in the area of early diagnosis and treatment mechanism. This review discusses the diabetic retinopathy, its pathogenesis, current treatment options, need of finding novel treatment options, and different epigenetic alterations associated with DR. However, the main focus is emphasized on various epigenetic modifications particularly DNA methylation which are responsible for the initiation and progression of diabetic retinopathy and the use of different epigenetic inhibitors as a novel therapeutic option for DR.

The Effects of Diabetic Duration on Lacrimal Functional Unit in Patients with Type II Diabetes

Purpose

To observe ocular surface changes in Type II diabetic patients with different disease durations and to understand the correlations between clinical parameters and diabetic durations.

Methods

In this cross-sectional, prospective study, 51 healthy controls and 91 patients with Type II diabetes were enrolled. The diabetics were divided into 3 subgroups according to the disease duration, including duration <10 y group, 10 to 20 y group, and ≥21 y group. All subjects underwent clinical ocular examinations, including lipid layer thickness (LLT), blinking rate, tear meniscus height (TMH), noninvasive tear film break-up time (NI-BUT), meibography, superficial punctate keratopathy (SPK) scoring, corneal sensitivity, and Schirmer I test. They were also evaluated using the standard patient evaluation of eye dryness (SPEED) questionnaire.

Results

SPEED score, meiboscore, SPK score, LLT, Schirmer I test, and corneal sensitivity differed significantly between the diabetic and healthy control groups. Further, SPEED score, Schirmer I test, corneal sensitivity, meiboscore, and blink rate significantly differed among the 3 diabetic subgroups and the control group. In diabetics, the SPEED score correlated with the SPK score, blink rate, TMH, and LLT; NI-BUT with TMH, LLT, and blink rate; TMH with the SPK score; Schirmer I test with the SPK score; and corneal sensitivity with the meiboscore. More importantly, the Schirmer I test, corneal sensitivity, and SPEED score negatively correlated with diabetic duration.

Conclusion

Diabetic duration is an important factor that affects functions of the lacrimal functional unit in patients with Type II diabetes. The trends of changes in the ocular parameters vary along the course of diabetes.

Awareness of diabetic retinopathy among people with diabetes in Jeddah, Saudi Arabia

BACKGROUND

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus (DM) and the foremost cause of blindness. This study aimed to assess the level of awareness of DR and its related risk factors among patients with DM in Jeddah, Saudi Arabia.

METHODS

A cross-sectional study was conducted among patients with DM attending primary health care centers at the Ministry of Health in Jeddah. A structured, pretested, self-administered questionnaire was used to collect information on the sociodemographic and DM- and DR-related characteristics of the patients.

RESULTS

A total of 377 patients were enrolled. About 82.6% of the patients were aware that DM can affect their eyes, and they listed physicians, ophthalmologists, television, and family members as common sources of information on the topic. About 36% of the patients reported that their doctors had not advised them about it. More than half responded that they did not feel their vision to be affected by DM. More than 58% had never been diagnosed with DR. About 35% did not go to their eye checkups, even though around 59% thought that DR could lead to blindness. Of the 64% of patients whose DM was well controlled, 11% and 25% listed surgery and laser treatment, respectively, as available treatment options for DR. The following factors were found to be significant in relation to the subjects' awareness that DM can affect their eyes: the patients' perception of their doctors' advice about DR; the experience of having their vision affected by DM; the knowledge that DR may lead to blindness; the practice of going to eye checkups.

CONCLUSIONS

Despite having good awareness about DM and its effects on eyes, the patients exhibited a relative lack of awareness about DR. Considering the association of DR with DM, its increasing magnitude is a potential burden on the community and health systems.

Diabetic Retinopathy in the Asia-Pacific

Diabetic retinopathy (DR), the most common complication of diabetes mellitus, is the leading cause of new cases of blindness in middle-aged and elderly in the Asia-Pacific. It has been estimated that 51% of all those with blindness due to DR globally (n = 424,400) and 56% of those with visual impairment due to DR (2.1 million) come from the Asia-Pacific. Prevalence of DR among those with diabetes ranged from 10% in India to 43% in Indonesia within the Asia-Pacific. Awareness of DR among persons with diabetes ranged from 28% to 84%. Most common modifiable risk factors for DR in the Asia-Pacific were hyperglycemia, blood pressure, dyslipidemia, and obesity. Implementation of systematic screening programs for DR and advancement in telemedicine screening methods have increased patient coverage and cost-effectiveness, though there are still numerous factors impeding screening uptake in the low-middle income regions of the Asia-Pacific. Management and treatment of DR in the Asia-Pacific is mainly limited to traditional laser retinopexy, but it is suboptimal despite new clinical approaches such as use of intravitreal anti.vascular endothelial growth factor and steroids due to limited resources. Further research and data are required to structure a more cost-effective public healthcare program and more awareness-building initiatives to increase the effectiveness of DR screening programs.

Prevalence of Diabetic Retinopathy and its Associated Factors in a Rural Area of Villupuram District of Tamil Nadu, India

INTRODUCTION

There is limited information on prevalence of Diabetic Retinopathy (DR) among diabetic subjects and its associated factors in a rural setting in developing countries including India. The information will be useful for initiating early screening strategies for this group in the community.

AIM

To assess the prevalence and certain associated factors of DR among diabetic subjects in a rural area of Tamil Nadu, India.

MATERIALS AND METHODS

This cross-sectional study was conducted among 105 Type 2 diabetic subjects in Pakkam and Mandagapattu sub-center area of Kondur Primary Health Center in Villupuram district of Tamil Nadu, India. Data on associated factors which include sociodemographic factors, duration of disease, family history, and frequency of blood test, treatment regularity, hypertension, visual acuity and cataract were collected. Detailed eye examination including visual acuity, direct ophthalmoscope and Non Mydriatic Fundus Camera was done. Data was analysed by univariate analysis and described in proportion or percentages.

RESULTS

The mean age of the study population was 56.69 years. About 47 (44.8%) of the subjects were more than 60 years of age followed by 44 subjects (41.9%) in age group 45-59 years. Fundus examination in at least one eye was seen in 83 people (79.0%). Prevalence of DR in any eye and both the eye was 32.53% (27/83) and 31.58% (24/76) respectively. Severity of DR was moderate (51.9%) followed by mild (44.4%) and severe (3.7%). DR prevalence was more among >60 years age group (p=0.032) and lesser education level (p=0.057). There was no association of DR with duration of disease, family history of diabetes, treatment regularity, presence of hypertension, visual acuity and cataract (p>0.05).

CONCLUSION

The prevalence of DR was inferred to be high and further larger follow up studies will explore the role of associated factors and its quantification in the causation of DR.

Glycated hemoglobin A1C and vitamin D and their association with diabetic retinopathy severity

OBJECTIVES

This retrospective, population-based, cross-sectional study evaluated the association between vitamin D deficiency and retinopathy severity in diabetic patients with poorly or well controlled glycaemia. Other potential risk factors for diabetic retinopathy severity were also assessed.

METHODS

The National Health and Nutrition Examination Survey (NHANES) 2005-2008 data were used for the study. Outcomes assessed included retinopathy severity, HbA1c levels, socioeconomic, behavioral, and biological factors. Univariate and multivariate regression analysis was used to evaluate association of different parameters with retinopathy severity. The interaction among HbA1c control, vitamin D deficiency, and retinopathy severity were also explored.

RESULTS

The population included 842 adults (52.8% women) with mean age of 61.2 years. Retinopathy was detected in 301 subjects (35.7%). Mild non-proliferative retinopathy (NPR) was present in 195 subjects (23.2%), severe non-proliferative and proliferative retinopathy in 106 subjects (12.6%). Multivariate ordinal regression analysis found being male (odds ratio (OR): 1.602, P=0.001), increased duration of diabetes (OR: 1.072, P=3.77E-7) and poorly controlled HbA1c (OR: 3.522, P=2.00E-5) were associated with greater retinopathy severity. The association between vitamin D deficiency and retinopathy severity only found in diabetic patients with well controlled glycaemia.

CONCLUSIONS

The findings of this study indicate that vitamin D deficiency associated with severe diabetic retinopathy in patients with well controlled diabetes. The findings provide possible relationship for the previous conflict results, and highlight the need for controlling modifiable risk factors to reduce the development of sever diabetic retinopathy.

Prevalence of type 2 diabetes and its complications in India and economic costs to the nation

Diabetes, a major lifestyle disorder, has become a global burden, and the prevalence rates are rising steeply in developing economies. Rapid socioeconomic transition with urbanization and industrialization are the main causes for the global diabetes epidemic. Among developing economies, the highest increase in number of people with diabetes is in China followed by India. In India, the epidemic of diabetes continue to increase and is experiencing a shift in diabetes prevalence from urban to rural areas, the affluent to the less privileged and from older to younger people. Diabetes is a progressive disorder leading to complications, which are broadly divided into small vessel or microvascular disease and large vessel or macrovascular disease. Microvascular complications affect the inner part of the eye-the retina known as diabetic retinopathy, the kidney termed as diabetic nephropathy and the peripheral nerves termed as diabetic neuropathy. The macrovascular complications affect the heart, the brain and the peripheral arteries termed as cardiovascular disease, cerebrovascular disease and peripheral vascular disease, respectively. Given the lifelong expenditure associated with diabetes and its complications, individuals, families and the society are unable to cope with the economic, emotional and social disease burden due to diabetes. The economic burden of diabetes can be reduced by providing universal healthcare coverage, access to affordable medicines and early detection and treatment of the disorder. This emphasizes the need for a multi-prolonged strategy to minimize the burden of diabetes and its complications.

HbA1c, systolic blood pressure variability and diabetic retinopathy in Asian type 2 diabetics

BACKGROUND

The aim of the present study was to examine the association between variability in HbA1c or systolic blood pressure (SBP) and diabetes-specific moderate retinopathy in Asians with type 2 diabetes (T2D).

METHODS

A retrospective study was conducted of 172 cases of moderate diabetic retinopathy (DR) cases and 226 controls without DR, matched for age, sex, and ethnicity. Serial HbA1c and SBP (range 3-6 readings) over the 2 years prior to photographic screening of DR were collected. Intrapersonal mean and SD values for HbA1c (iM-HbA1c and iSD-HbA1c) and SBP (iM-SBP and iSD-SBP) were derived. Moderate DR was assessed from digital retinal photographs and defined as levels >43 using the Early Treatment Diabetic Retinopathy Study scale.

RESULTS

Cases of moderate DR had higher iM-HbA1c (8.2 % vs 7.3 %; P = 0.001), iSD-HbA1c (1.22 vs 0.64; P = 0.001), iM-SBP (136.8 vs 129.6 mmHg; P = 0.001) and iSD-SBP (13.3 vs 11.1; P = 0.002) than controls. In the multivariate regression model adjusted for age, gender, ethnicity, duration of diabetes, SBP, and HbA1c, iM-HbA1c and iM-SBP were significantly associated with moderate DR (odds ratio [OR] 1.80, 95 % confidence interval [CI] 1.37-2.36; and OR 1.03, 95 % CI 1.01-1.05, respectively). Neither iSD-HbA1c nor iSD-SBP were associated with moderate DR. When stratified by HbA1c <7 %, only iSD-SBP remained significantly associated with moderate DR (OR 1.11, 95 % CI 1.01-1.21).

CONCLUSION

In a cohort of Asian patients with T2D, both higher mean HbA1c levels and SBP, but not their variability, were associated with moderate DR. Among those with good glycemic control, wider variability of SBP is associated with moderate DR.

Risk factors for diabetic retinopathy: a case-control study

BACKGROUND

Diabetic retinopathy (DR) is the major cause of blindness among working age adults. The aim of the study was to investigate risk factors for development of DR.

METHODS

A case-control study was performed based on data from 240 individuals (80 cases and 160 controls) attending the Outpatient Specialty Clinic of the University of South Santa Catarina (UNISUL), between Mar/2010 and May/2014. Data collection occurred through review of medical charts for presence or absence of DR, determined by an ophthalmologist. Study protocol included demographic characteristics, metabolic control, diabetes mellitus (DM) profile and comorbidities. Statistical analysis used Chi square test for qualitative variables and multivariate logistic regression analysis to select independent variables (SPSS®18.0 software). Odds ratio (OR) was used as measure of association. The study was approved by research ethics committee of UNISUL.

RESULTS

Mean age of group case was 59.5 years with a slight female predominance. Gender, age, body mass index were not associated with outcome. Individuals with poor glycemic control were more likely to DR (OR 3.83; 95 % CI 1.57-9.37). It was observed a positive relationship between duration of DM and DR, with higher chances in 11-15 years of disease (OR 7.52, 95 % CI 3.03-18.68) and >15 years (OR 9.01, 95 % CI 3.58-22.66). Regarding comorbidities, only diabetic nephropathy showed higher chance for DR (OR 3.32; 95 % CI 1.62-6.79).

CONCLUSIONS

Diabetic patients after 10 years of disease with poor glycemic control and nephropathy have a higher chance of DR.

Risk factors for diabetic retinopathy in northern Chinese patients with type 2 diabetes mellitus

AIM

To investigate the prevalence and risk factors of diabetic retinopathy (DR) in northern Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

This retrospective cross-sectional study was performed between May 2011 and April 2012. A total of 1100 patients (male/female, 483/617) were included in this study. DR was defined following the Early Treatment Diabetic Retinopathy Study (ETDRS) severity scale. All included patients accepted a comprehensive ophthalmic examination including retinal photographs. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence interval (CI) after adjusting for age and gender.

RESULTS

Retinopathy was present in 307 patients with a prevalence of 27.9%. In univariate logistic analysis, presence of DR was associated with longer duration of diabetes (OR, 5.70; 95%CI, 2.91-12.56), higher concentration of fasting blood glucose (OR, 12.94; 95%CI, 2.40-67.71), higher level of glycosylated hemoglobin HbA1c (OR, 5.50; 95%CI, 3.78-11.97) and insulin treatment (OR, 6.99; 95%CI, 1.39-35.12). The lifestyle of patients with T2DM including smoking, alcohol consumption and regular exercise seemed not associated with the development of DR.

CONCLUSION

Our study suggests that fasting serum glucose concentration, HbA1c level, duration of diabetes and insulin treatment are potential risk factors for DR in northern Chinese patients with T2DM, while the lifestyle of included patients seems not associated with DR.

Epidemiology of microvascular complications of diabetes in South Asians and comparison with other ethnicities

Type 2 diabetes mellitus is widely prevalent in South Asians, and has a significant effect on health, as well as the economies of South Asian countries, particularly when the disease is associated with complications. There are certain characteristics associated with the South Asian phenotype that make South Asians especially prone to diabetes, as well as its complications. Microvascular complications cause considerable morbidity and mortality. There are significant differences in the epidemiology of microvascular complications between South Asians and people of other races. There is evidence of higher prevalence of nephropathy and retinopathy in South Asians compared with Caucasians; however, recent studies indicate that this trend seems to be leveling off. Importantly, diabetic neuropathy occurs less frequently in South Asians compared with Caucasians. These observations have important implications in managing South Asian patients with diabetes and microvascular complications.

Ten Emerging Trends in the Epidemiology of Diabetic Retinopathy

PURPOSE

Diabetes is a major public health problem affecting 415 million people worldwide. With the increasing prevalence of diabetes, diabetic retinopathy (DR) is emerging as the leading cause of avoidable blindness worldwide.

METHODS

We reviewed previous and recent literature to provide an overview of emerging trends on the burden, epidemiology, risk factors, and prevention of DR.

RESULTS

First, there is clear evidence of a global increase in the prevalence of diabetes. Second, there is a decline in the incidence of blindness due to DR, particularly in developed countries. Third, diabetic macular edema (DME) rather than proliferative diabetic retinopathy (PDR) is the increasingly common cause of visual impairment. Fourth, DR awareness remains patchy and low in most populations. Fifth, hyperglycemia remains the most consistent risk factor for DR in type 1 diabetes across different studies and populations. Sixth, in contrast, blood pressure is an important risk factor for DR in type 2 diabetes. Seventh, the relationship between dyslipidemia and DR remains unclear, with inconsistent results from different studies and trials. Eighth, the utility of predictive models incorporating multiple risk factors for assessing DR risk requires evaluation. Ninth, photographic screening of DR using tele-ophthalmology platforms is increasingly recognized as being feasible and cost-effective. Finally, DR prevention in low-resource settings cannot follow models developed in high-resource countries and requires different strategies.

CONCLUSIONS

The ten trends we observed in the current review may guide planning of public healthcare strategies for the management of DR and prevention of blindness.

A Hospital Based Study Regarding Awareness of Association Between Glycosylated Haemoglobin and Severity of Diabetic Retinopathy in Type 2 Diabetic Individuals

INTRODUCTION

Diabetic retinopathy is one of the most common microvascular complications seen in diabetic patients after a long term of uncontrolled glycaemic status as assessed by glycosylated Haemoglobin A (HbA1c). Hence awareness of glycaemic control is necessary to prevent vision threatening complications.

AIM

To assess the awareness regarding association between glycosylated Haemoglobin (HbA1c) and diabetic retinopathy among diabetic patients and to assess the impact of lack of this knowledge on the severity of diabetic retinopathy (DR).

MATERIALS AND METHODS

This hospital based cross-sectional study was conducted in the ophthalmology OPD on 200 adult diabetic patients, between November 2012 and January 2013, who were assessed for their knowledge regarding association between HbA1c and its impact on the progress of DR. The study was done with the help of a semi structured questionnaire which included demographic details, literacy levels, diabetic status and awareness of HbA1c.

STATISTICS USED

Cochran Armitage test for trend, Fisher Exact test, chi-square for trend and Student's t test.

RESULTS

Among the 200 diabetic individuals attending our OPD, 180 (90%) were aware of the importance of blood sugar levels and its fluctuation in type 2 diabetes. Only 23 (11.5%) were aware of HbA1c whereas 10 (5%) misinterpreted it as levels of haemoglobin, 3 (1.5%) did not completely comprehend. About 164 (82%) patients were not aware of the significance or the terminology of HbA1c. Out of the 200 patients, 58 patients showed presence of some grade of DR. Amongst these 58 patients, 7(12.1%) were aware of HbA1c and all the11 patients with clinically significant macular oedema (CSME) were aware of the risk factors of elevated blood sugar levels but ignorant of HbA1c. Among the remaining 142 individuals who showed no signs of DR, 16 (27.5%) were aware of and comprehended the role of HbA1c.

CONCLUSION

Our study highlights the gross ignorance of role of HbA1c in the progress of DR among diabetic individuals. It is a known fact that the risk of DR reduces by 35% for every 1% reduction in HbA1c. Hence a strict control of blood sugar level with regular monitoring of HbA1c can help diabetic individuals in prevention of progress of DR, thus preventing severe vision loss.

Clinical Evaluation of Correlation Between Diabetic Retinopathy with Modifiable, Non-Modifiable and Other Independent Risk Factors in Tertiary Set-up in Central Rural India

INTRODUCTION

Diabetes mellitus and its related ocular complication like diabetic retinopathy (DR) are showing increased prevalence in India, but the magnitude of presence and progression of DR in central rural population and its relation to certain variables requires further exploration.

AIM

To study the demographic profile on diabetic retinopathy and the association between different risk factors of diabetic retinopathy with its onset and severity.

MATERIALS AND METHODS

A cross-sectional study was carried out on patients suffering from diabetes mellitus (n=100) admitted to AVBRH, Sawangi (Meghe) in a duration of 2 months from April to June 2014. Snellen's chart, slit lamp, and indirect ophthalmoscope were used for ocular examination of all patients. Comprehensive examination was used for risk factor assessment.

STATISTICAL ANALYSIS

All data was entered into the proforma. Chi-square test, Student's unpaired t-test and one way ANOVA using SPSS 17.0 and Graph Pad Prism 5.0. (p<0.05 was considered significant).

RESULTS

The study showed that among all the diabetics (mean age 56.4+11.2 years), 68% were males and 97% type 2 diabetics. This study showed statistically significant association between serum triglyceride (p=0.0003), duration since diagnosis of diabetes mellitus (p=0.0006), serum total cholesterol (p=0.0021), FBG (p=0.003), serum HDL (p=0.012) and hypertension (p=0.045) with presence of diabetic retinopathy. The study also revealed that serum triglycerides (p=0.001), serum total cholesterol (p=0.006), BMI (p=0.04) and duration of diabetes (p=0.04) are the only factors which showed significant association with the severity of diabetic retinopathy.

CONCLUSION

Effective screening strategies for early detection of both diabetes and diabetic retinopathy should be formulated especially for the rural population which is not aware about the various complications of diabetes and their final outcomes. Diabetics should follow proper guidelines to prevent or delay progression of DR.

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.

Risk factors associated with diabetic retinopathy among type 2 diabetes patients at teaching hospital in Malaysia

BACKGROUND

Diabetic retinopathy (DR) is the leading cause of blindness in the United States and it is the leading cause of new cases of blindness in adults aged 20-74. It is estimated that about 20% of patients with type 2 DM have evidence of diabetic retinopathy at diagnosis with diabetes.

OBJECTIVE

To evaluate the prevalence of DR and to determine risk factors related to diabetic retinopathy among type 2 diabetes patients attending endocrinology clinics at Hospital Universiti Sains Malaysia (HUSM).

SUBJECTS AND METHODS

The study design was observational prospective longitudinal follow-up study, the study was conducted with sample of 1077 type 2 diabetes mellitus outpatient recruited via attended the diabetes clinics at HUSM. Diagnosis of retinopathy is based on finding the diagnostic signs of retinopathy on eye exams by fundoscopy. Logistic regression analysis was used to assess the independent variables that affect the development of retinopathy.

RESULTS

The prevalence of retinopathy was 39.3%. It has been noticed from this study findings, that the progression of retinopathy is been influenced by five independent risk factors such as duration of diabetes, presence neuropathy, total cholesterol at second and third visit and createnine clearance.

CONCLUSION

DR is highly prevalent among type 2 DM. The progression of retinopathy is been influenced by five independent risk factors such as duration of diabetes, presence neuropathy, total cholesterol at second and third visit and createnine clearance. DR is a serious diabetic complication and public health strategies are required in order to reduce its risk factors and decrease its prevalence.

Body mass index and retinopathy in Asian populations with diabetes mellitus

Body mass index (BMI) is an established risk factor for diabetes. However, the association between BMI and diabetic retinopathy (DR) has been inconclusive. We aimed to assess the association between BMI and DR in a large population-based sample of multi-ethnic Asian adults in Singapore. We examined 2,278 adults aged ≥40 years with diabetes who participated in three population-based studies conducted from 2004 to 2011: the Singapore Malay Eye Study, the Singapore Indian Eye Study, and the Singapore Chinese Eye Study. Retinal photographs taken from both eyes were graded for any and vision-threatening (VTDR) using the modified Airlie House Classification. BMI (kg/m(2)) was categorized into normal/underweight (<25), overweight (25-29.9), and obese (≥30). The prevalence rates of any and VTDR in the study population were 35.1 % and 9.1 %, respectively. The prevalence of any and VTDR decreased with increasing categories of BMI (P trend <0.001 and 0.005). In multivariable models adjusted for potential confounders, compared to those with normal weight, the odds ratio (95 % confidence interval) of any DR was 0.71 (0.57-0.88) for overweight and 0.70 (0.53-0.92) for obese. Corresponding estimates for VTDR were 0.84 (0.59-1.21) for overweight and 0.58 (0.35-0.94) for obese. The inverse association between BMI and any DR was consistently present when BMI was analyzed as a continuous variable and in analyses stratified by ethnicity and age. In a population-based sample of multi-ethnic Asian adults, BMI levels were inversely associated with any DR and VTDR.

The effects of renal transplantation on diabetic retinopathy: clinical course and visual outcomes

PURPOSE

To elucidate the clinical course of diabetic retinopathy (DR) after renal transplantation (RT) in a hospital based cohort.

DESIGN

Retrospective study.

MATERIALS AND METHODS

A total of 56 eyes of 28 patients, who had DR and end stage renal disease (ESRD) due to diabetes and had undergone RT, were included in this study. Diagnosis and management of DR was carried out according to early treatment of diabetic retinopathy study (ETDRS) guidelines. DR outcome was defined as worsening if there was >2 step increase in the grade of DR or need for intervention such as laser (macular or pan retinal) or vitreoretinal surgery, improvement for <2 step change while stabilization was defined if DR remained within these two limits.

RESULTS

The mean age of the patients were 48.9 years. The mean duration of diabetes in the study group was 12.7 years. The patients were followed-up for a mean period of 52.2 ± 43.6 months. The pre-transplant mean Best corrected visual acuity (BCVA) was 0.4876 log MAR units and post-transplant mean BCVA was 0.4858 (P = 0.05). However, there was a significant visual improvement in first 20 months of renal transplant (P = 0.03). Worsening of DR was noted in 16 (32%) eyes whereas improvement was seen in 4 (8%). However, majority of eyes 30 (60%) had stable retinopathy at the final follow-up.

CONCLUSIONS

RT stabilized the retinopathy status in the majority of patients although in a minor subset the disease course was unpredictable.

Prevalence and risk factors for diabetic retinopathy in rural India. Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study III (SN-DREAMS III), report no 2

OBJECTIVE

The study was aimed at estimating the prevalence of type 2 diabetes mellitus and diabetic retinopathy in a rural population of South India.

DESIGN

A population-based cross-sectional study.

PARTICIPANTS

13 079 participants were enumerated.

METHODS

A multistage cluster sampling method was used. All eligible participants underwent comprehensive eye examination. The fundi of all patients were photographed using 45°, four-field stereoscopic digital photography, and an additional 30° seven-field stereo digital pairs were taken for participants with diabetic retinopathy. The diagnosis of diabetic retinopathy was based on Klein's classification.

MAIN OUTCOME MEASURES

Prevalence of diabetes mellitus and diabetic retinopathy and associated risk factors.

RESULTS

The prevalence of diabetes in the rural Indian population was 10.4% (95% CI 10.39% to 10.42%); the prevalence of diabetic retinopathy, among patients with diabetes mellitus, was 10.3% (95% CI 8.53% to 11.97%). Statistically significant variables, on multivariate analysis, associated with increased risk of diabetic retinopathy were: gender (men at greater risk; OR 1.52; 95% CI 1.01 to 2.29), use of insulin (OR 3.59; 95% CI 1.41 to 9.14), longer duration of diabetes (15 years; OR 6.01; 95% CI 2.63 to 13.75), systolic hypertension (OR 2.14; 95% CI 1.20 to 3.82), and participants with poor glycemic control (OR 3.37; 95% CI 2.13 to 5.34).

CONCLUSIONS

Nearly 1 of 10 individuals in rural South India, above the age of 40 years, showed evidence of type 2 diabetes mellitus. Likewise, among participants with diabetes, the prevalence of diabetic retinopathy was around 10%; the strongest predictor being the duration of diabetes.

Diabetic Retinopathy-Update on Prevention Techniques, Present Therapies, and New Leads

Diabetic retinopathy is the major ocular complication associated with diabetes, and represents the leading cause of legal blindness in the working-age population of developed countries. Although classically diagnosed based on abnormalities of the retinal microvasculature, diabetic retinopathy is now widely recognized as a neurovascular disease. While all patients with diabetes are at increased risk for eye disease including diabetic retinopathy, proactive measures, and timely intervention can prevent or delay subsequent vision loss. Systemic management of diabetes by combined control of glycemia, blood pressure, and serum lipid levels remains the most important method of preventing diabetic retinopathy onset and progression. Once detected, surgical and medical interventions including photocoagulation, vitrectomy, and intravitral drug injection can help preserve vision. However, the need for improved detection methods and therapies that will allow earlier diagnosis and treatment remains apparent. This review summarizes current techniques for the prevention and intervention for diabetic retinopathy, and examines ongoing developments in the search for new endpoints and therapies as they apply to preventing vision loss associated with diabetes.

Predictors of diabetic retinopathy in patients with type 2 diabetes who have normoalbuminuria

Background:

Microalbuminuria is an independent predictor of retinopathy, so absence of microalbuminuria may tend clinician not to screen for diabetic retinopathy (DR).

Aim:

The aim of our study was to estimate prevalence of DR in patients with type 2 diabetes who have normoalbuminuria, and to study predictors for DR, which can identify these high-risk individuals.

Subjects and Methods:

In a prospective cross-sectional study that included patients with type 2 DM and normoalbuminuria. Diagnosis of DR was made by a trained ophthalmologist based on the presence of clinical features in the fundus of both eyes following the International Clinical DR guidelines. The statistical analyses were performed using Statistical Package for the Social Sciences 15.0 version software (Chicago, IL, USA). The continuous variables expressed as means (SD and Student's t-test or Mann–Whitney test were used, as appropriate, to determine differences in them. Categorical variables were presented as percentage. The Pearson's Chi-square test or Fisher's exact test, as appropriate, was used to determine the differences in them.

Results:

A total of 226 patients with type 2 DM and normoalbuminuria were enrolled in the study that included 110 males (48.6%), and 116 females (51.4%) Mean (SD) duration of diabetes was 8.2 (5.6) years. DR of any grade was present in 49/226 (22%) patients. Of the patients with DR of any grade, 31/49 (63%) had mild non-proliferative diabetic retinopathy (NPDR) 10/49 (22%) had moderate to severe NPDR and 8/49 (15%) had PDR. Duration of diabetes (OR 1.01, 95% CI, 0.86-2.2, P = 0.04), higher systolic blood pressure (OR 2.2, 95% CI, 1.6-4.5, P = 0.01), low hemoglobin (OR 1.4, 95% CI, 0.45-2.9, P = 0.01), and a higher tertile of urinary albumin excretion rate (OR 4.12, 95% CI, 1.92-7.57, P = 0.001) had independently significant association with DR.

Conclusion:

The risk of DR exists in patients with type 2 diabetes even in normoalbuminuric individuals. Close monitoring is particularly needed if patients have longer duration of diabetes, hypertension, anemia, or high normal albuminuria.

Prevention of diabetes in rural India with a telemedicine intervention

BACKGROUND

Diabetes care is not presently available, accessible, or affordable to people living in rural areas in developing countries, such as India. The Chunampet Rural Diabetes Prevention Project (CRDPP) was conceived with the aim of implementing comprehensive diabetes screening, prevention, and treatment using a combination of telemedicine and personalized care in rural India.

METHODS

This project was undertaken in a cluster of 42 villages in and around the Chunampet village in the state of Tamil Nadu in southern India. A telemedicine van was used to screen for diabetes and its complications using retinal photography, Doppler imaging, biothesiometry, and electrocardiography using standardized techniques. A rural diabetes center was set up to provide basic diabetes care.

RESULTS

Of the total 27,014 adult population living in 42 villages, 23,380 (86.5%) were screened for diabetes, of which 1138 (4.9%) had diabetes and 3410 (14.6%) had prediabetes. A total of 1001 diabetes subjects were screened for complications (response rate of 88.0%). Diabetic retinopathy was detected in 18.2%, neuropathy in 30.9%, microalbuminuria in 24.3%, peripheral vascular disease in 7.3%, and coronary artery disease in 10.8%. The mean hemoglobin A1c levels among the diabetes subjects in the whole community decreased from 9.3 ± 2.6% to 8.5 ± 2.4% within 1 year. Less than 5% of patients needed referral for further management to the tertiary diabetes hospital in Chennai.

CONCLUSIONS

The Chunampet Rural Diabetes Prevention Project is a successful model for screening and for delivery of diabetes health care and prevention to underserved rural areas in developing countries such as India.

Plasma plasminogen activator inhibitor-1 is associated with end-stage proliferative diabetic retinopathy in the Northern Chinese Han population

Objective. To identify predictors of end-stage proliferative diabetic retinopathy (PDR) in a cohort of individuals with type 2 diabetes mellitus (T2DM) from the Northern Chinese Han population. Methods. We investigated characteristics of 153 consecutive diabetic patients with end-stage PDR (62 males, 91 females), 123 consecutive PDR patients without end-stage PDR (48 males, 75 females), and 151 normal subjects (63 males, 88 females). Only one eye of each patient or healthy subject was included in this study. Univariate logistic regression models and multivariate logistic regression models were constructed to evaluate the predictors of end-stage PDR. Results. In univariate analysis, systolic blood pressure, diastolic blood pressure, duration of diabetes, family history of T2DM, and plasminogen activator inhibitor-1 (PAI-1) were significently associated with end-stage PDR. After multivariate analysis, family history of T2DM, plasma PAI-1 levels, smoking, and duration of diabetes were four positive predictors associated with end-stage PDR. Conclusions. Higher plasma levels of PAI-1 were associated with end-stage PDR in the Northern Chinese Han population with T2DM.

Prevalence and risk factors of diabetic retinopathy in subjects with suboptimal glycemic, blood pressure and lipid control. Sankara Nethralaya Diabetic Retinopathy Epidemiology and Molecular Genetic Study (SN-DREAMS, Report 33)

PURPOSE

To assess the rate of achieving optimal metabolic control among subjects with type 2 diabetes, to elucidate the influence of suboptimal control on diabetic retinopathy (DR) and to analyze the risk factors associated with DR in the subjects with suboptimal control.

MATERIAL AND METHODS

A population-based, cross-sectional study was conducted in south India. The study population consisted of 1414 subjects with type 2 diabetes. Optimal control of glycosylated hemoglobin (HbA1c), blood pressure (BP) and lipids was defined as: optimal HbA1c <7%, suboptimal HbA1c ≥ 7%; optimal BP ≤ 130/80 mm Hg, suboptimal BP >130/80 mm Hg; optimal low-density lipoprotein (LDL-C) <100 mg/dl, suboptimal LDL ≥ 100 mg/dl.

RESULTS

Of the subjects, 13.6% achieved combined optimal target levels for all metabolic parameters. When compared to subjects with optimal control, those with suboptimal control of HbA1c (trend P < 0.0001) and systolic blood pressure (SBP, trend P = 0.007) were more likely to have DR. Subjects having a combination of suboptimal glycemic and BP control (P < 0.0001 for SBP, P = 0.004 for diastolic blood pressure (DBP)), and suboptimal glycemic, BP and LDL control (P < 0.0001 for SBP, P = 0.017 for DBP), were more likely to have DR when compared to the subjects having optimal control of respective combinations. The factors associated with DR in the subjects with suboptimal control were younger age (P = 0.014 for BP, P = 0.016 for HbA1c), male gender (P = 0.035 for BP, P = 0.027 for HbA1c, P = 0.043 for LDL), presence of anemia (P = 0.021 for BP, P = 0.036 for HbA1c) and microalbuminuria (P < 0.0001 for both BP and HbA1c).

CONCLUSIONS

We found high prevalence of suboptimal metabolic control among subjects with type 2 diabetes. Suboptimal glycemic and SBP control, and their combination was the most detrimental for the development of DR.

Risk factors for progression of diabetic retinopathy in Alberta First Nations communities

OBJECTIVE

The Screening for Limb, I-Eye, Cardiovascular, and Kidney Complications (SLICK) Program was implemented in 1999 to improve diabetic care for Alberta First Nations individuals living on reserve. The purpose of this review is to determine the rate and predictors of progression of diabetic retinopathy (DR) over a 10-year period.

DESIGN

Cohort study.

PARTICIPANTS

Nine hundred and eighty First Nations patients with diabetes that underwent at least 2 teleophthalmology examinations during the study period.

METHODS

Patients underwent serial laboratory testing, and stereoscopic, mydriatic, retinal photography. Modified Early Treatment Diabetic Retinopathy Study grading of retinal images was performed via teleophthalmology. Progression was defined as an increase of 2 or more steps on the Diabetes Control and Complications Trial classification.

RESULTS

At baseline, most patients had no diabetic retinopathy (n = 777, 79.3%) whereas 203 people (20.7%) had either nonproliferative DR (n = 179, 18.3%) or proliferative DR (n = 24, 2.5%). Two-step progression occurred in 163 patients (16.6%), with only a minority of these individuals progressing to proliferative DR (n = 23). The median time to progression was 7.6 years. Multivariate Cox regression demonstrated that elevated hemoglobin A1C (hazard ratio [HR] = 1.42; p < 0.0001) and systolic blood pressure (HR = 1.24 per 10 mm Hg; p = 0.009) were independent predictors of progression of DR.

CONCLUSIONS

This population-based study has shown that the rate and predictors of progression of DR among First Nations individuals parallels non-First Nations populations, with HbA1C and systolic blood pressure being the strongest predictors. These findings suggest that targeted, individualized care to reduce blood pressure and control blood sugars could reduce progression of diabetic retinopathy, and possibly blindness in First Nations individuals living on reserve.

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.

Retinopathy and risk factors in diabetic patients from Al-Madinah Al-Munawarah in the Kingdom of Saudi Arabia

Background

Diabetes mellitus is accompanied by chronic and dangerous microvascular changes affecting most body systems, especially the eye, leading to diabetic retinopathy. Diabetic retinopathy without appropriate management is emerging as one of the leading causes of blindness. Therefore, it is necessary to improve the early diagnosis of diabetic retinopathy, reduce the risk of blindness, and identify relevant risk factors.

Methods

This descriptive study was designed to estimate the prevalence of retinopathy and its staging in diabetic patients attending the diabetes clinic at King Fahd Hospital in Al-Madinah Al-Munawarah, Kingdom of Saudi Arabia, from 2008 to 2010. Patients completed a questionnaire, underwent a full medical assessment carried out by the treating clinicians, and were examined for evidence of diabetic retinopathy using standard ophthalmic outpatient instruments.

Results

In total, 690 randomly selected diabetic patients of mean age 46.10 ± 11.85 (range 16–88) years were included, comprising 395 men (57.2%) of mean age 46.50 ± 11.31 years and 295 women (42.8%) of mean age 45.55 ± 12.53 years. The mean duration of diabetes mellitus was 11.91 ± 7.92 years in the women and 14.42 ± 8.20 years in the men, and the mean total duration of known diabetes mellitus was 13.35 ± 8.17 years. Glycated hemoglobin was higher in men (8.53% ± 1.81%) than in women (7.73% ± 1.84%), and this difference was statistically significant (P ≤ 0.0001). Of the 690 diabetic patients, 249 (36.1%) had retinopathy. Mild nonproliferative diabetic retinopathy was present in 13.6% of patients, being of moderate grade in 8% and of severe grade in 8.1%. A further 6.4% had proliferative diabetic retinopathy.

Conclusion

Regular screening to detect diabetic retinopathy is strongly recommended because early detection has the best chance of preventing retinal complications.

Factors associated with diabetic retinopathy in chinese patients with type 2 diabetes mellitus

Objective. To investigate the risk factors of DR in Chinese T2DM patients. Methods. 2009 patients with T2DM were included in this cross-sectional study. All patients underwent eye examination, and the DR stage was defined by an ophthalmologist. Correlation analysis was performed to evaluate the relation between DR and clinical variables. Logistic regression models were used to assess risk for those factors associated with DR. Results. A total of 597 T2DM patients (29.7%) had DR, of which 548 (27.3%) were nonproliferative diabetic retinopathy and 49 (2.4%) were proliferative diabetic retinopathy. Positive correlations were found between DR and duration of diabetes, systolic blood pressure (SBP), diastolic blood pressure, glycated hemoglobin, glycated albumin, 24 hurinary albumin excretion, peripheral atherosclerosis (PA), diabetes nephropathy (DN), diabetic peripheral neuropathy, and anemia. Negative correlations were found between DR and C-peptide and glomerular filtration rate. Logistic regression analysis revealed that duration of diabetes, SBP, DN, anemia, PA, and C-peptide were each independent risk factors of DR. Conclusion. The duration of diabetes, SBP, DN, anemia, and PA are positively associated with DR in Chinese T2DM patients, while C-peptide is negatively associated with DR. Monitoring and evaluation of these related factors will likely contribute to the prevention and treatment of DR.

Prevalence and associated factors of diabetic retinopathy in rural Korea: the Chungju metabolic disease cohort study

This study was aimed to investigate the prevalence of diabetic retinopathy and its associated factors in rural Korean patients with type 2 diabetes. A population-based, cross-sectional diabetic retinopathy survey was conducted from 2005 to 2006 in 1,298 eligible participants aged over 40 yr with type 2 diabetes identified in a rural area of Chungju, Korea. Diabetic retinopathy was diagnosed by a practicing ophthalmologist using funduscopy. The overall prevalence of diabetic retinopathy in the population was 18% and proliferative or severe non-proliferative form was found in 5.0% of the study subjects. The prevalence of retinopathy was 6.2% among those with newly diagnosed type 2 diabetes and 2.4% of them had a proliferative or severe non-proliferative diabetic retinopathy. The odds ratio of diabetic retinopathy increased with the duration of diabetes mellitus (5-10 yr: 5.2- fold; > 10 yr: 10-fold), postprandial glucose levels (> 180 mg/dL: 2.5-fold), and HbA1c levels (every 1% elevation: 1.34-fold). The overall prevalence of diabetic retinopathy in rural Korean patients was similar to or less than that of other Asian group studies. However, the number of patients with proliferative or severe non-proliferative diabetic retinopathy was still high and identified more frequently at the time of diagnosis. This emphasizes that regular screening for diabetic retinopathy and more aggressive management of glycemia can reduce the number of people who develop diabetic retinopathy.

Influence of glycosylated hemoglobin on sight-threatening diabetic retinopathy: a population-based study

AIM

To evaluate the role of glycosylated hemoglobin (HbA1c) on the occurrence of sight-threatening diabetic retinopathy (STDR) in urban Chennai, Tamil Nadu, India.

METHODS

A total of 5999 individuals were enumerated from the Chennai metropolis. Of these, 1414 subjects with diabetes were included for data analysis in the study. STDR or non-STDR groups were classified based on the fundus photographs. HbA1c was measured (Bio-Rad DiaSTAT™ HbA1c Reagent Kit) by the liquid chromatography technique.

RESULTS

A statistically significant difference (p < 0.05) was noted in the duration of diabetes, gender, body mass index, HbA1c, micro- and macro-albuminuria between both non-STDR and STDR groups as compared to the no-diabetic retinopathy (DR) group. On multivariate analysis, HbA1c (non-STDR: odd's ratio OR = 1.23; 95% confidence interval CI = 1.15-1.32; p < 0.0001; STDR: OR = 1.31 95% CI = 1.14-1.52; p < 0.0001) was found to be significantly associated with non-STDR and STDR when compared with the no-DR group. The Receiver Operating Characteristic analysis showed that the cut-off value of 8.0 had 75.6% sensitivity and 58.2% specificity with 64.9% maximum area under the curve.

CONCLUSION

HbA1c value >8.0% was significantly related with STDR. In a screening programme, the cut-off value of HbA1c >8.0% provided a maximum yield of STDR.

Risk factors associated with retinal neovascularization of diabetic retinopathy in type 2 diabetes mellitus

AIM

To evaluate the risk factors associated with retinal neovascularization of diabetic retinopathy in northern Chinese Han patients with type 2 diabetes mellitus (T2DM).

METHODS

The clinical characteristics of 200 patients with proliferative diabetic retinopathy (PDR) and 100 age-matched healthy individuals were compared. The univariate and multivariate logistic regression analysis were performed in the patients with PDR.

RESULTS

Fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), blood urea nitrogen (BUN), uric acid (UA), white blood cell count (WBC), absolute neutrophil count, hematocrit (HCT) and mean platelet volume (MPV) and mean platelet volume (MPV) were all significantly higher in patients with PDR than in the control group (P<0.05). The univariate and multivariate logistic regression analysis showed that risk factors independently associated with retinal neovascularization of DR were duration of diabetes mellitus (OR=1.112; P=0.000), BUN (OR=1.277; P=0.000), smoking (OR=3.967; P=0.000) and MPV (OR=2.472; P=0.000). On the other hand, panretinal photocoagulation was associated with reduced risk of retinal neovascularization (OR=0.983; P=0.000).

CONCLUSION

Preventing and controlling T2DM in terms of risk factors, including duration of diabetes, BUN, smoking and MPV, might offer novel approaches to prevent or delay the onset of retinal neovascularization in patients with PDR.

Risk factors associated with diabetic retinopathy in patients with diabetes mellitus type 2

Background

Diabetes mellitus (DM) is associated with microvascular complications, such as diabetic retinopathy (DR). DR is one of the main causes of visual loss in individuals aged 20-64 years old. This study aims to investigate the independent associations between the stage of DR and a variety of possible risk factors, including years since DM diagnosis, HbA_1c levels, the coexistence of hypertension, age and gender.

Findings

120 patients were recruited in the Department of Internal Medicine, Veroia General Hospital, Veroia, Greece, and the DR stage was defined by an ophthalmologist. Afterwards, the DR association with the aforementioned factors was examined. Univariate and multivariate analysis (multivariate ordinal logistic regression) was performed. At the univariate analysis, there was a positive association between DR severity and age (Spearman's rho = 0.4869, p < 0.0001), years since DM diagnosis (Spearman's rho = 0.6877, p < 0.0001), HbA_1c levels (Spearman's rho = 0.6315, p < 0.0001), history of hypertension (2.47 ± 1.37 vs. 0.50 ± 0.80 for patients without hypertension; p < 0.0001) and male sex (2.56 ± 1.41 vs. 2.05 ± 1.45 for female patients; p = 0.045, MWW). All these factors, except for age, retained their statistical significance at the multivariate ordinal logistic model.

Conclusions

Years since DM diagnosis, hypertension, HbA_1c levels and male sex are independently associated with severe DR. The effect of age seems to reflect a confounding association.