The 5-year onset and regression of diabetic retinopathy in Chinese type 2 diabetes patients

Burden of diabetic macular oedema and its associated factors among adult patients with diabetes attending comprehensive specialised hospitals in Northwest Ethiopia, 2023: a multicentre cross-sectional study

OBJECTIVE

This study aimed to assess the prevalence of diabetic macular oedema and its associated factors among adult patients with diabetes attending comprehensive specialised hospitals in Northwest Ethiopia in 2023.

DESIGN

An institution-based, cross-sectional study.

SETTING

The study was conducted at the University of Gondar, Felege Hiwot and Debre Markos comprehensive specialised hospitals in Northwest Ethiopia from 8 May to 15 June 2023.

PARTICIPANTS

This study was conducted on 890 adult patients with diabetes selected using a systematic random sampling technique.

OUTCOME MEASURES

Participants with diabetic macular oedema were assessed using slit lamp biomicroscopy with a +90 dioptre Volk lens. Blood glucose levels were measured by fasting blood sugar tests. Data were collected through physical examination, review of medical records and face-to-face interview.

RESULTS

Among a total of 890 study participants, the prevalence of diabetic macular oedema was 25.8% (95% CI 23.1 to 28.8). Peripheral neuropathy (adjusted OR (AOR)=3.02, 95% CI 1.76 to 5.29), hypertension (AOR=1.98, 95% CI 1.24 to 3.17), poor blood glucose control (AOR=5.06, 95% CI 2.95 to 8.67), obesity (AOR=5.03, 95% CI 2.50 to 10.13), longer duration of diabetes mellitus (AOR=3.78, 95% CI 2.21 to 6.24) and poor adherence to diabetic medication (AOR=2.06, 95% CI 1.32 to 3.28) were significantly associated with diabetic macular oedema.

CONCLUSION

In Northwest Ethiopia, a quarter of patients with diabetes were found to have diabetic macular oedema. Factors such as peripheral neuropathy, hypertension, poor blood glucose levels, obesity, long duration of diabetes mellitus and poor adherence to diabetic medications were significantly associated with diabetic macular oedema. Improvement of glucose control and exercise for optimal body weight maintenance are recommended to prevent the development of diabetic macular oedema.

A meta-analysis of prevalence of diabetic retinopathy in Asia

INTRODUCTION

Diabetic retinopathy (DR) is a common microvascular complication of diabetes. This review reports the prevalence of DR in Asia and guides healthcare provision in screening and treatment.

EVIDENCE ACQUISITION

Medline was searched for articles describing the prevalence of DR in Asia. Statistical analysis was performed using Freeman-Tukey double arcsine transformation and the DerSimonian and Laird model. The prevalence of DR was estimated according to the following subgroups: Economic status (high, middle, and low income), country, and ethnicity. The risk of bias of the articles was also assessed.

EVIDENCE SYNTHESIS

A total of 66 studies were included, and out of 2,599,857 patients with diabetes, 201,646 were diagnosed with DR. The overall prevalence of DR, non-proliferative DR (NPDR), proliferative DR (PDR) and maculopathy were recorded at 21.7% (CI: 19.1-24.6%), 19.9% (CI: 17.3-22.8%), 2.3% (CI: 1.6-3.4%) and 4.8% (CI: 3.5-6.7%) respectively. Low-income countries had the lowest prevalence of DR, NPDR, PDR and maculopathy compared to the middle- and high-income countries. Middle-income countries had the highest prevalence of DR (23.9%; CI: 19.4-29.2%), NPDR (21.1%; CI: 17.0-25.9%), moderate NPDR (7.9%; CI: 5.7-11.0%), PDR (3.0%; CI: 1.8-4.9%) and maculopathy (4.7%; CI: 3.0-7.4%), while high-income countries had the highest prevalence of mild (10.3%; CI: 4.2-23.2%) and severe NPDR (3.0%; CI: 1.0-8.4%).

CONCLUSIONS

One in five people with diabetes have diabetic retinopathy. It is imperative that public healthcare take heeds to heighten the screening program to provide all patients with diabetes equitable access to DR screening and ophthalmology services.

Diabetic retinopathy among the elderly with type 2 diabetes: A Nationwide longitudinal registry study

PURPOSE

To investigate the prevalence, incidence and risk factors of DR in elderly people living with type 2 diabetes.

METHODS

Individuals >80 years, in the Swedish National Diabetes Register (NDR) between 2008 and 2017, were included. Prevalence and incidence were calculated and stratified by age. Estimates were assessed by longitudinal binary logistic regression models.

RESULTS

One hundred forty-one thousand, one hundred fifty-eight individuals with type 2 diabetes were included, median age 83 years, 53.3% females and with a median HbA1c 52 mmol/mol. The DR prevalence was stable at 336.2 cases/1000 patients in 2008 (95% CI, 330.2-342.3), with no significant changes during the 10-year period. Crude DR incidence rate: 88.5 cases/1000 patient years (95% CI, 87.6-89.4). The incidence rate was lower at higher ages. The effect of age on incident DR varied by sex, with females having an increasingly higher risk than males from 83 years of age, OR 1.25 (1.11-1.42) at age 90 years. The risk of incident DR with longer diabetes duration increased more rapidly at worse glycaemic control.

CONCLUSION

The growing population of elderly with type 2 diabetes shows a stable proportion of DR and proposes an increased need for DR screening and eye care. Established risk factors for DR, such as diabetes duration and level of glycaemic control, are also important in the elderly; however, age and sex should be considered.

Visual Outcome after Anti-Vascular Epithelial Growth Factor Therapy Using New Classification of Diabetic Macular Edema by Optical Coherence Tomography

INTRODUCTION

The aim of the study was to examine alterations in visual acuity in patients with diabetic macular edema (DME), classified according to the TCED-HFV optical coherence tomography (OCT) system, following anti-vascular epithelial growth factor (VEGF) therapy.

METHODS

The medical records of patients with DME receiving anti-VEGF therapy were retrospectively reviewed. Patients were divided into four groups according to the TCED-HFV OCT classification. Patient demographic and clinical characteristics and best-corrected visual acuity (BCVA) before and after treatment were compared among the groups.

RESULTS

The BCVA before treatment was 0.49 ± 0.18, 0.81 ± 0.41, 0.83 ± 0.41, and 0.82 ± 0.49 in the early DME, advanced DME, severe DME, and atrophic maculopathy groups, respectively. The BCVA in the early DME group was therefore significantly lower than that in the other three groups (p = 0.042). After treatment, the BCVA improved to 0.15 ± 0.17, 0.52 ± 0.31, 0.62 ± 0.32, and 0.69 ± 0.47 in the early DME, advanced DME, severe DME, and atrophic maculopathy groups, respectively (p < 0.005). There were some differences among patients in the four groups in terms of the duration of diabetes, percentage of hemoglobin A1c, and duration of hypertension.

CONCLUSION

The TCED-HFV OCT classification of patients with DME is exact and functional and can allow the severity of DME, and its response to anti-VEGF therapy, to be estimated.

Assessing the possible association between MTHFR (rs1801133) and GPx-1 (rs1050450) polymorphisms with the risk of type 2 diabetes, diabetic neuropathy, and diabetic retinopathy

PURPOSE

Oxidative stress in chronic hyperglycemia could injure the tissues and onset of diabetes-related complications like retinopathy and neuropathy. This study investigates the association between methylenetetrahydrofolate reductase (MTHFR) and glutathione peroxidase (GPx) genetic variants with these complications.

METHODS

In this case-control study, 400 individuals, including 100 healthy subjects and 300 patients with type 2 diabetes mellitus (T2DM) in three subgroups: with retinopathy(n = 100), with neuropathy(n = 100), and without complication (n = 100) from West Iran, were studied. MTHFR (rs1801133) and GPx-1 (rs1050450) variants were identified by the PCR-RFLP method. The plasma levels of GPx activity, glutathione, malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidative stress (TOS) were measured by chemical methods.

RESULTS

Higher BMI, TOS and MDA levels were observed in patients with neuropathy compared to other patients and controls. Diabetic patients with neuropathy had lower levels of glutathione (7.8 ± 4.5; P < 0.001), GPx activity (39.5 ± 8.5; P < 0.001), and TAC (703.1 ± 129.1; P = 0.0001) in comparison with other groups. The patients without complication and retinopathic patients had higher plasma levels of glutathione (12.2 ± 2.4; p = 0.02) and TAC (793.4 ± 124.6; P < 0.001), respectively. MTHFR TT genotype significantly correlated with lower levels of TOS (3.5 ± 1.1; P < 0.001) and OSI (0.0050 ± 0.001; P < 0.001). Subjects with the GPx-1 TT genotype had higher levels of MDA (6.8 ± 2.5; P = 0.02) and lower levels of TOS (3.7 ± 1.6; P < 0.001), which is statistically significant. TT genotype of MTHFR was associated with 3.9 fold (95% CI 1.04-4.76; P = 0.0436) increased risk of neuropathy. Also, GPx-1 CT genotype increased the risk of retinopathy [OR = 2.7 (95% CI = 1.38-5.44; P = 0.0039)].

CONCLUSION

The MTHFR TT genotype increased the risk of neuropathy in diabetic patients significantly. The GPx-1 CT genotype is related to increased retinopathy risk among diabetic patients. Both MTHFR and Gpx-1 TT genotypes were associated with higher BMI levels.

Economic evaluation for medical artificial intelligence: accuracy vs. cost-effectiveness in a diabetic retinopathy screening case

Artificial intelligence (AI) models have shown great accuracy in health screening. However, for real-world implementation, high accuracy may not guarantee cost-effectiveness. Improving AI's sensitivity finds more high-risk patients but may raise medical costs while increasing specificity reduces unnecessary referrals but may weaken detection capability. To evaluate the trade-off between AI model performance and the long-running cost-effectiveness, we conducted a cost-effectiveness analysis in a nationwide diabetic retinopathy (DR) screening program in China, comprising 251,535 participants with diabetes over 30 years. We tested a validated AI model in 1100 different diagnostic performances (presented as sensitivity/specificity pairs) and modeled annual screening scenarios. The status quo was defined as the scenario with the most accurate AI performance. The incremental cost-effectiveness ratio (ICER) was calculated for other scenarios against the status quo as cost-effectiveness metrics. Compared to the status quo (sensitivity/specificity: 93.3%/87.7%), six scenarios were cost-saving and seven were cost-effective. To achieve cost-saving or cost-effective, the AI model should reach a minimum sensitivity of 88.2% and specificity of 80.4%. The most cost-effective AI model exhibited higher sensitivity (96.3%) and lower specificity (80.4%) than the status quo. In settings with higher DR prevalence and willingness-to-pay levels, the AI needed higher sensitivity for optimal cost-effectiveness. Urban regions and younger patient groups also required higher sensitivity in AI-based screening. In real-world DR screening, the most accurate AI model may not be the most cost-effective. Cost-effectiveness should be independently evaluated, which is most likely to be affected by the AI's sensitivity.

A Review on Diabetic Retinopathy

Diabetic retinopathy is a well-recognised microvascular complication of diabetes and is among the leading cause of blindness all over the world. Over the last decade, there have been advances in the diagnosis of diabetic retinopathy and diabetic macular edema. At the same time, newer therapies for the management of diabetic retinopathy have evolved. As a result of these advances, a decline in severe vision loss due to diabetes has been witnessed in some developing countries. However, there is a steady increase in the number of people affected with diabetes, and is expected to rise further in the coming years. Therefore, it is prudent to identify diabetic retinopathy, and timely intervention is needed to decrease the burden of severe vision loss. An effort has been made to review all the existing knowledge regarding diabetic retinopathy in this article and summarize the present treatment options for diabetic retinopathy.

Relationship between dyslipidemia and diabetic retinopathy in patients with type 2 diabetes mellitus: a systematic review and meta-analysis

BACKGROUND

Diabetic retinopathy (DR) affects more than 80% of patients with diabetes. However, literature on the association between serum lipids and DR in patients with type 2 diabetes mellitus (T2DM) is inconsistent. Hence, in this study, we aimed to investigate the relationship between baseline serum lipids and the incidence of DR in patients with T2DM.

METHODS

We searched relevant articles in the PubMed, Embase databases, and the Cochrane Library up to February 7, 2022, and reviewed the reference lists of the included articles to identify appropriate cohort studies. The weighted mean difference (WMD) and the corresponding 95% confidence intervals (CIs) were calculated.

RESULTS

Thirteen cohort studies, including 7459 participants, were included in the present study. Higher levels of total cholesterol (2.94 mg/dL, 95% CI 1.32, 4.56), triglycerides (8.13 mg/dL, 95% CI 5.59, 10.66), and low-density lipoprotein cholesterol (2.53 mg/dL, 95% CI 1.02, 4.04) at baseline were observed in patients with later onset of DR. However, no significant difference in the high-density lipoprotein cholesterol level (0.27 mg/dL, 95% CI - 0.91, 1.45) was observed between patients with DR and without DR.

CONCLUSION

The present results suggest that baseline triglyceride and cholesterol levels are significantly associated with the occurrence of DR in patients with T2DM. Thus, patients with T2DM may benefit from lowering serum lipids. Future studies exploring the relationship between longitudinal changes in serum lipids and DR occurrence are warranted.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022319978.

Associations between blood pressure levels and diabetic retinopathy in patients with diabetes mellitus: A population-based study

Purpose

To evaluate the associations of blood pressure levels with diabetic retinopathy (DR), proliferative diabetic retinopathy (PDR) and diabetic macular edema (DME) in patients with diabetes mellitus.

Design

A cross-sectional, population-based study.

Subjects

A total of 152,844 patients with diabetes from 90 major cities in 19 provincial regions of mainland China during 2018-2021 were finally recruited.

Methods

Blood pressure was graded into 5 levels: normal (without hypertension and <120/80 mmHg), normal high (without hypertension and ≥120/80 mmHg), HT-intensive (hypertension and <120/80 mmHg), HT-moderate (hypertension and blood pressure between 120/80 mmHg and 140/90 mmHg) and HT-high (hypertension and ≥140/90 mmHg). Logistic regression was employed to verify the associations of hypertension and blood pressure levels with DR, PDR and DME. The impacts of blood pressure levels on the outcomes were qualified with nomogram models.

Main outcome measures

The main outcome was DR.

Results

There were 16,685 (10.92%) participants having DR, 2841 (1.86%) having PDR, and 1566 (1.02%) having DME. There were 8126 (5.32%) patients without hypertension and 1350 (0.88%) patients with hypertension having blood pressure <120/80 mmHg. When compared to the normal group with covariates adjusted, an increased prevalence of DR was observed in normal high (adjusted odds ratio [OR] = 1.114, 95% confidence interval [CI] = 1.033-1.202), HT-moderate (adjusted OR = 1.163, 95% CI = 1.065-1.271), and HT-high (adjusted OR = 1.203, 95% CI = 1.114-1.300).

Conclusions

There were associations between hypertension and DR, PDR, and DME in the diabetic population. Increased prevalence of DR was found with blood pressure >120/80 mmHg in both patients with and without hypertension. A nomogram was developed for DR prediction based on blood pressure levels.

Spontaneous Resolution of Tractional Retinal Detachment in a Type II Diabetic Patient

A 43 years old male with diabetes type II was under treatment for diabetic retinopathy with extramacular tractional retinal detachment (TRD) in the left eye OS. During the follow-up visit, the patient had a drop in vision from 20/25 to 20/60. The TRD was found to have progressed to involve the macula and was threatening the fovea; therefore, vitrectomy was thought to be inevitable. Meanwhile, the patient adopted exercise and tight glycemic control, and during the preoperative evaluation of three months duration, we observed resolution of traction and return of visual acuity to baseline (20/20). In conclusion, spontaneous resolution of TRD is extremely rare. If it occurs, the patient may be spared from undergoing a vitrectomy.

Population attributable fractions of modifiable risk factors for microvascular complications of type 2 diabetes in China: An analysis using national cross-sectional data

AIM

To assess the population attributable fractions (PAFs) for modifiable risk factors for microvascular complications of type 2 diabetes (T2D) in China.

MATERIALS AND METHODS

Data collected from the China National HbA1c Surveillance System from 2009 to 2013 were used. The PAFs of four predefined risk factors, including an HbA1c of 7% or higher, blood pressure (BP) of 130/80 mmHg or higher, low-density lipoprotein-cholesterol (LDL-C) of 1.8 mmol/L or higher and body mass index (BMI) of 24 kg/m² or higher, were calculated for diabetic microvascular complications, including diabetic retinopathy (DR), diabetic kidney disease (DKD) and distal symmetric polyneuropathy (DSPN). PAFs were further adjusted for age, sex and duration of diabetes.

RESULTS

In total, there were 998 379 participants with T2D from nationwide mainland China included in this analysis. As for DR, an HbA1c of 7% or higher, BP of 130/80 mmHg or higher, LDL-C of 1.8 mmol/L or higher and BMI of 24 kg/m² or higher conferred PAFs of 16.2%, 15.2%, 5.8% and 2.8%, respectively. In the case of DKD, BP of 130/80 mmHg or higher provided a PAF of 25.2%, followed by an HbA1c of 7% or higher (13.9%), BMI of 24 kg/m² or higher (8.0%) and LDL-C of 1.8 mmol/L or higher (5.6%). As for DSPN, an HbA1c of 7% or higher, BP of 130/80 mmHg or higher, LDL-C of 1.8 mmol/L or higher and BMI of 24 kg/m² or higher contributed to PAFs of 14.2%, 11.7%, 5.9% and 5.8%, respectively. PAFs for diabetic microvascular complications were mildly to moderately reduced after adjusting for participants' age, sex and duration of diabetes.

CONCLUSIONS

Suboptimal glycaemic and BP control were the main contributors to diabetic microvascular complications, while the PAFs of unmet LDL-C and BMI control targets were quite limited for diabetic microvascular complications. In addition to glycaemic control, BP control should be especially prioritized in the management of diabetic microvascular complications to further reduce the disease burden.

Time to Diagnosis and Treatment of Diabetes Mellitus among Korean Adults with Hyperglycemia: Using a Community-Based Cohort Study

OBJECTIVES

To identify the time from hyperglycemia to diabetes mellitus (DM) diagnosis and treatment, the risk factors for diabetes development, and the prevalence of comorbidities/complications in patients > 40 years of age.

METHODS

This secondary data analysis study used data from the Korean Genome and Epidemiology Study. The participants comprised 186 patients who did not have diabetes at baseline, but developed hyperglycemia at the first follow-up. The average and median periods until DM diagnosis and treatment were calculated using Kaplan-Meier survival analysis.

RESULTS

Of the 186 participants, 57.0% were men and 35.5% were 40-49 years old. The average time to DM diagnosis and treatment was 10.87 years and 11.34 years, respectively. The risk factors for the duration of DM were current smoking, body mass index (BMI), fasting blood sugar (FBS), and postprandial 2-hour glucose (PP2). The risk factors for the duration of diabetes treatment were current smoking, hypertension, BMI, FBS, and PP2. The development of one or more comorbidities or diabetes complications was identified at the time of DM diagnosis (36.5%) and DM treatment (41.4%).

CONCLUSIONS

As diabetes complications occur at the time of DM, and early treatment can impact the development of diabetes complications or mortality, it is necessary to establish a referral program so that participants presenting with high blood sugar levels in the screening program can be diagnosed and treated in a timely manner.

Prevalence of Impairment of Visual Acuity and Severity of Retinopathy in Patients with Diabetes Mellitus

AIMS

No information exists on the frequency of visual impairment in people with diabetes mellitus (DM) in Germany. In this study, the prevalence of vision impairment in those individuals was investigated.

METHODS

We retrospectively analyzed a cohort of 295 people (14221 consultations) at a university outpatient clinic with any type of DM and an available ETDRS-Score and visual acuity. The primary outcome was the prevalence of visual impairment, the secondary outcome was the correlation of the ETDRS-Score and limitations of visual acuity and the prevalence of higher ETDRS-Score with a visual impairment defined as a decimal-visus</=0.3.

RESULTS

The prevalence of visual impairment in participants with DM was 11.2%; among these individuals, 81.8% had no or non-proliferative retinopathy. In the DM2 subgroup, 81.5% (n=22) of the visually impaired participants had no DR, in contrast to only 16.7% (n=1) in the DM1 subgroup. Progression in ETDRS-Score led to worse visual acuity (r=-0.209; p<0.001). A significantly related covariates with impairment of the visual acuity for individuals with DM1 was the duration of diabetes (B=-0.007; p=0.001) and for individuals with DM2, the age (B=-0.008; p=0.009).

CONCLUSIONS

The prevalence of impaired vision in people with diabetes in our cohort was 11.2%,<20% of visual impairment in people with diabetes is caused by diabetic retinopathy, and 69.7% of participants with visual impairment had no DR. In our study patients without visual impairment showed a similar distribution of DR severity levels regardless of the type of diabetes.

Incidence, progression and regression of diabetic retinopathy in a northeastern Chinese population

AIM

To determine the incidence, progression and regression of diabetic retinopathy (DR), with corresponding risk factors, in a northeastern Chinese population of patients with type 2 diabetes.

METHODS

Among 2006 patients who completed baseline examinations in 2012-2013 and underwent re-examination after a mean interval of 21.2 months, 1392 patients with gradable fundus photographs for both baseline and follow-up examinations were included. Incidence was defined as new development of any DR among patients without DR at baseline. An increase of ≥2 scales (concatenating Early Treatment Diabetic Retinopathy Study levels of both eyes) in eyes with DR at baseline was defined as progression, while a reduction of ≥2 scales was defined as regression.

RESULTS

The age- and sex-standardised incidence, progression and regression were 5.8% (95% CI 4.7% to 6.9%), 26.8% (95% CI 24.8% to 28.8%) and 10.0% (95% CI 8.6% to 11.3%), respectively. In addition to poor blood glucose control, wider central retinal venular equivalent was associated with both incidence (relative risk (RR) 2.17, 95% CI 1.09 to 4.32, for ≥250 µm vs <210 µm) and progression (RR 2.00, 95% CI 1.02 to 3.96, for ≥250 µm vs <210 µm). Patients without insulin therapy (RR 0.64, 95% CI 0.43 to 0.97) and patients with wider central retinal arteriolar equivalent (RR 1.14, 95% CI 1.02 to 1.26, per 10 µm increase) were likely to exhibit DR regression.

CONCLUSION

We determined the incidence, progression and regression of DR among northeastern Chinese patients with type 2 diabetes. Retinal vessel diameters, in addition to blood glucose level, influence the natural evolution of DR.

The Association Between Diabetic Retinopathy and the Prevalence of Age-Related Macular Degeneration—The Kailuan Eye Study

This study aimed to investigate the prevalence of age-related macular degeneration (AMD) in patients with diabetes mellitus (DM) and diabetic retinopathy (DR) and analyze whether DR is a risk factor for AMD. This population-based epidemiological study included 14,440 people from the Kailuan Eye Study in 2016, of whom 1,618 were patients with type 2 DM aged over 50 years, and 409 had DM with DR. We analyzed whether there were differences in the prevalence of AMD between DM with DR and DM without DR, and conducted a hierarchical statistical analysis according to different stages of DR. Using variable regression analysis, we explored whether DR constituted a risk factor for AMD. In the DM population, the prevalence of wet AMD in patients with DM with and without DR was 0. 3 and 0.2%, respectively, with no significant difference (P = 0.607). Meanwhile, the prevalence of dry AMD in patients with DM with and without DR was 20.8 and 16.0%, respectively, with a significant difference. In the subgroup analysis of dry AMD, the prevalence of early, middle, and late dry AMD in DM with DR was 14.4, 5.9, and 0.5%, respectively. In DM without DR, the prevalence of early, middle, and late dry AMD was 10.5, 4.8, and 0.7%, respectively (P = 0.031). In the subgroup analysis of DR staging, statistical analysis could not be performed because of the limited number of patients with PDR. In the variable regression analysis of risk factors for dry AMD, after adjusting for age, sex, body mass index, hypertension, and dyslipidemia, DR constituted the risk factor for dry AMD. In conclusion, DM did not constitute a risk factor for AMD, and the prevalence of wet AMD and dry AMD in patients with DM and DR was higher than that in patients with DM without DR (among which dry AMD was statistically significant). Multivariate regression analysis confirmed that DR is an independent risk factor for dry AMD. Reasonable control of DM and slowing down the occurrence and development of DR may effectively reduce the prevalence of AMD in patients with DM.

Latent Diabetic Macular Edema in Chinese Diabetic Retinopathy Patients

Purpose: To compare the detection rates of optical coherence tomography (OCT) and fluorescein angiography (FA) in a diabetic macular edema (DME) and the severity of diabetic retinopathy in both color fundus images (CFI) and FA, and to investigate the predictive factors in macular leakages in FA.

Methods: This was a retrospective study, and a total of 132 eyes of 77 patients with diabetic retinopathy were enrolled. Macular OCT, FA, and CFI were reviewed and measured. Central foveal thickness was also measured.

Results: The severity of diabetic retinopathy in FA was significantly higher than that in CFI (p < 0.001). OCT detected 26 eyes with DMEs, which included the following: 13 eyes with cystoid macular edemas; 13 eyes with serous retinal detachments; 11 eyes with diffuse retinal thickening; 4 eyes with vitreomacular interface abnormalities. In contrast, 72 out of 132 eyes (54.5%) showed macular leakages in FA, which was significantly higher than that detected by OCT (p < 0.001). Compared with FA, the sensitivity and the specificity of OCT in detecting DMEs were 30.6 and 93.3%, respectively. However, central foveal thickness was not significantly different between the patients with non-clinically significant macular edema (CSME, 253.1 ± 26.95 μm) and slight CSME (270.9 ± 37.11 μm, p = 0.204). The mean central foveal thickness in diabetic macular edema (FA) eyes was 271.8 ± 66.02 μm, which was significantly higher than that (253. ± 25.21 μm) in non-DME (FA) eyes (p = 0.039). The central foveal thickness in DME (FA) eyes was significantly lower than that in eyes with DME (OCT) (p = 0.014). After adjusting for age and sex, a logistic regression analysis showed that the classification of diabetic retinopathy in FA was positively associated with macular leakage in FA (p < 0.001).

Conclusions: The severity of diabetic retinopathy is underestimated in CFI compared with that in FA. FA can detect latent DMEs, which appeared normal on OCT. The central foveal thickness is not a sensitive parameter for detecting latent DMEs.

Obesity and risk of age-related eye diseases: a systematic review of prospective population-based studies

BACKGROUND

Obesity is a public health challenge worldwide. The relationship between obesity and age-related eye diseases including cataract, glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR) have remained elusive.

DESIGN AND METHODS

We conducted a systematic review of three electronic databases for longitudinal population-based studies that described associations between measures of obesity including body mass index (BMI), waist-circumference (WC), and waist-to-hip ratio (WHR), and age-related eye diseases.

RESULTS

Our search yielded 1731 articles, of which 14, 10, 16 and 8 articles met our eligibility criteria for cataract, glaucoma, AMD and DR, respectively. BMI-defined obesity was positively associated with incident cataract, incident AMD and incident DR in Western populations, but in Asian populations associations for incident AMD were not significant and associations for incident DR were inverse. WC-defined obesity was associated with incident glaucoma in non-Western populations. WHR-defined obesity but not BMI-defined obesity was associated with the incidence or progression of AMD in two Western studies.

CONCLUSIONS

Overall, we found strong evidence supporting associations between obesity and age-related eye diseases. Further research on the association of abdominal obesity and effect of weight loss and physical activity on age-related eye diseases is warranted to support clinical and public health recommendations.

Declined incidence of patients treated for vision-threatening diabetic retinopathy in South Korea: a 12-year nationwide population-based study

PURPOSE

To determine the age- and sex-specific annual incidence rates of patients treated for VTDR and the factors associated with increased treatment rates in patients with type 2 diabetes mellitus (T2DM) in South Korea.

METHODS

This was a nationwide, retrospective, 12-year, population-based study. Patients aged over 30 years who were diagnosed with T2DM between 2006 and 2017 were included in this study. We evaluated the national health claims data acquired from the Korean National Health Insurance Service database. Main outcome measures were the annual incidence rates of patients treated for VTDR and the associated risk factors.

RESULTS

The age-adjusted annual incidence rate of patients treated for VTDR significantly decreased from 10.05 per 1000 T2DM patients in 2006 to 6.11 in 2017 (β =  - 0.3192, P < 0.0001). The sex-adjusted annual incidence rate also significantly decreased in both men (β =  - 0.2861, P < 0.0001) and women (β =  - 0.3666, P < 0.0001). Cox hazard analysis showed that factors such as insulin use, young age, chronic kidney disease and male sex were significantly associated with increased rate of treatments for VTDR. In addition, the risk was lower for rural than for metropolitan residents.

CONCLUSIONS

Despite the increase in the number of T2DM patients in South Korea, the incidence rate of patients treated for VTDR decreases with early diagnosis and appropriate treatment. Therefore, it is important to detect and manage high-risk groups early to prevent visual impairment due to VTDR.

Prevalence and risk factors of diabetic retinopathy in patients with type 2 diabetes in Shanghai

AIM

To investigate the prevalence of diabetic retinopathy (DR) in residents of Shanghai and analyze the risk factors of DR.

METHODS

This study involved 7233 patients with diabetes in 2016. The demographic data of the participants were collected using a questionnaire survey. Physical examination, laboratory tests, and ophthalmological examinations were conducted. Two professional ophthalmologists diagnosed and graded DR by fundus examination and then combined the results with fundus images. The unconditional multivariate Logistic regression analysis was used to determine the risk factors.

RESULTS

In total, 6978 patients with type 2 diabetes in Shanghai with a mean age of 68.33±8.40y were recruited, including 2975 males (42.6%) and 4003 females (57.4%). Overall, 1184 patients were diagnosed with DR, with a prevalence rate of 16.97%. Regression analysis showed that duration of diabetes (OR 1.061, 95%CI 1.049-1.073), high systolic blood pressure (SBP; OR 1.071, 95%CI 1.037-1.106), increased glycosylated hemoglobin level (OR 1.234, 95%CI 1.162-1.311), high blood glucose level (OR 1.061, 95%CI 1.023-1.099), increased neutrophil-to-lymphocyte ratio (NLR; OR 1.132, 95%CI 1.053-1.217) and mean platelet volume (MPV; OR 1.077, 95%CI 1.016-1.142) were risk factors of DR. Conversely, hematocrit (HCT; OR 0.971, 95%CI 0.954-0.988) and mean corpuscular volume (MCV; OR 0.980, 95%CI 0.965-0.994) were protective factors.

CONCLUSION

The prevalence rate of DR in Shanghai is 16.97%. The duration of diabetes, high SBP, increased glycosylated hemoglobin, NLR, and MPV were determined as risk factors of DR.

Diabetes onset at an earlier age and high HbA1c levels as risk factors of diabetic retinopathy

AIM

To assess the effect of age at diabetes onset and uncontrollable high HbA1c levels on the development of diabetic retinopathy (DR) among Chinese type 2 diabetes mellitus (DM) patients.

METHODS

This was a cross-sectional survey of diabetic patients in Subei district, China. Data covering physical measurements, fasting blood-glucose (FBG), glycosylated hemoglobin (HbA1c), blood lipid, urinary albumin/creatinine ratio (UACR), ocular fundus examination, and diabetes treatment records were collected. An independent sample t-test were used to analyze differences. A Logistic regression analysis was applied to study the independent risk factors of DR.

RESULTS

A total of 1282 patients with type 2 DM were enrolled, and 191 cases had DR (14.9%). The age at diabetes onset, education level, alcohol consumption, HbA1c level, UACR level, and hypoglycemic drugs were independent influencing factors for DR. The older the onset of diabetes, the less likely to develop DR (OR: 0.958, 95%CI: 0.942-0.975, P=0.000). Patients were then divided in terms of age at diabetes onset as follows: <50y, 50-59y, 60-69y, and ≥70y. Compared with diabetes onset age <50y, 50-59y (OR: 0.463, 95%CI: 0.306-0.699, P=0.000), 60-69y (OR: 0.329, 95%CI: 0.203-0.535, P=0.000) and ≥70y (OR: 0.232, 95%CI: 0.094-0.577, P=0.002) were at a lower risk of DR. The prevalence of DR was highest in patients with diabetes onset age <50y (29.5%, P<0.05). The HbA1c level (8.67±1.97)% and proportion of insulin injection (52.5%) in patients with diabetes onset <40y were higher than in patients with older diabetes onset age (P<0.05).

CONCLUSION

Diabetes onset at an earlier age and uncontrollable high HbA1c level could be independent risk factors for DR.

Burden of disease and costs associated with type 2 diabetes in emerging and established markets: systematic review analyses

Objectives: To estimate the clinical and economic burden of type 2 diabetes (T2D) in established (EST) and emerging markets (EMG).Methods: Three systematic literature reviews were conducted in MEDLINE and Embase to capture all relevant publications reporting 1) the epidemiology of T2D and complications in T2D and 2) the economic burden of T2D and associated complications.Results: In total, 294 studies were included in this analysis. Evidence indicates a high and increasing overall prevalence of T2D globally, ranging up to 23% in EMG markets and 14% in EST markets. Undiagnosed cases were higher in EMG versus EST markets (up to 67% vs 38%), potentially due to a lack of education and disease awareness in certain regions, that could lead to important clinical and economic consequences. Poor glycemic control was associated with the development of several complications (e.g. retinopathy, cardiovascular diseases and nephropathy) that increase the risk of morbidity and mortality. Direct costs were up to 9-fold higher in patients with vs without T2D-related complications.Conclusions: The burden of T2D, related complications and inherent costs are higher in emerging versus established market countries. This review explores potential strategies to reduce costs and enhance outcomes of T2D treatment in developing countries.

Prevalence and associated risk factors of diabetic retinopathy and macular oedema in patients recently diagnosed with type 2 diabetes

Objective

To determine the prevalence of diabetic retinopathy (DR) and diabetic macular oedema (DME) and their associated risk factors in patients recently diagnosed with type 2 diabetes.

Methods and analysis

We carried out a cross-sectional study from April 2014 to August 2017. We included patients aged ≥18 years. Diabetes was defined as fasting plasma glucose of >7.8 mmol/L or 2-hour postload plasma glucose of >11.1 mmol/L. Non-mydriatic fundus examination with a digital-fundus camera was performed. Three images centred in the macula, optic disc and temporal to the macula were obtained and graded according to the Scottish Scale Classification of Diabetic Retinopathy.

Results

1232 patients (mean age 51.5 years) with a diabetes duration of 0–5 years were examined. Age-adjusted and sex-adjusted prevalence of DR and DME was 17.4% (95% CI 15.3% to 19.6%) and 6.6% (95% CI 5.4% to 8.2%), respectively. DR was associated with diabetes duration (OR per year=1.20, p<0.001), haemoglobin A1c (HbA1c) from 7.0 to 8.9 (OR=2.19, p<0.001), HbA1c≥9 (OR=2.98, p<0.001) and systolic blood pressure (SBP) (OR=1.16 per 5 mm Hg, p<0.001). DME was associated with diabetes duration (OR per year=1.26, p<0.01), HbA1c from 7.0 to 8.9 (OR=2.26, p<0.05), HbA1c≥9 (OR=2.38, p<0.01), SBP (OR per mm Hg=1.15, p<0.001) and albuminuria (OR=2.45, p<0.01).

Conclusion

Our study contributes to the evidence of progressive increase in DR and DME risk in early stages of diabetes, supporting the urgent need for early screening.

Analysis of association between common variants of uncoupling proteins genes and diabetic retinopathy in a Chinese population

BACKGROUND

The aim of this study was to explore the association between diabetic retinopathy (DR) and the variants of uncoupling proteins (UCPs) genes in a Chinese population of type 2 diabetes, in total and in patients of different glycemic status separately.

METHODS

This case-control study included a total of 3107 participants from two datasets, among which 662 were DR patients (21.31%). Eighteen tag single nucleotide polymorphisms (SNPs) of UCP1, UCP2, and UCP3 were selected as genetic markers. TaqMan probes, Sequenom MassARRAY MALDI-TOF mass spectrometry platform and Affymetrix Genome-Wide Human SNP Array were used for genotyping. Online SHEsis software was used for association analysis. Bonferroni correction was used for multiple comparisons correction.

RESULTS

Three SNPs of UCP1: rs7688743 (A allele, OR = 1.192, p = 0.013), rs3811787 (T allele, OR = 0.863, p = 0.023), and rs10011540 (G allele, OR = 1.368, p = 0.004) showed association with DR after the adjustment of glucose, but only rs10011540 was marginally significantly associated with DR when Bonferroni correction was strictly applied (p_adj = 0.048). In patients with uncontrolled glucose, rs7688743 (A allele, p = 0.012, OR = 1.309), rs10011540 (G allele, p = 0.033, OR = 1.432), and rs3811787 (T allele, p = 0.022, OR = 0.811) were associated with DR, while in participants with well controlled glucose, the rs2734827 of UCP3 was associated with DR (A allele, p = 0.017, OR = 0.532). Rs3811787 of UCP1 showed a protective effect to sight threatening DR (T allele, p = 0.007, OR = 0.490), and the association existed after the adjustment for environmental factors and the correction. In patients with uncontrolled glucose, the rs3811787 of UCP1 (T allele, p = 0.017, OR = 0.467) and the rs591758 of UCP3 (C allele, p = 0.026, OR = 0.103) were associated with STDR. While in those with well controlled glucose, only the rs7688743 of UCP1 showed a protective effect (A allele, p = 0.024, OR = 0.049). None of the associations remain significant when Bonferroni correction was strictly applied (all p < 0.05).

CONCLUSIONS

The rs10011540 and rs3811787 of the UCP1 gene was marginally significantly associated with DR in Chinese type 2 diabetes patients. There might be different mechanisms of DR development in patients with different glycemic status.

Screening for retinopathy in children with type 1 diabetes in Denmark

BACKGROUND/OBJECTIVE

Children with type 1 diabetes (T1D) are screened regularly for retinopathy with fundus photography to prevent visual impairment. According to Danish national guidelines, screening should take place at age 12, 15, and 18 years after minimum 3 years of diabetes. As glycemic control has improved, prevalence of retinopathy is expected to be decreased. The aim of this study is to investigate the prevalence, degree, and progression of retinopathy in children with T1D and to explore if screening at 12 years is currently indicated in Denmark.

METHODS

Data on all Danish children with onset of T1D from 2003 to 2013 (n = 2943) were collected from the "DanDiabKids" registry. For children with registered screenings (n = 2382), prevalence of retinopathy at 12, 15, and 18 years was determined. In children with retinopathy, subsequent screenings were studied to reveal if retinopathy was persistent or temporary.

RESULTS

Prevalence of retinopathy at 12, 15, and 18 years was 0.9%, 2.3%, and 3.1%, respectively. Minimal background retinopathy was seen in over 90% and 100% at 12 years. In available re-screenings, retinopathy resolved spontaneously in 87.5% of all cases and 100% of cases at 12 years.

CONCLUSIONS

The prevalence of retinopathy in Danish children with T1D was low. At 12 years, prevalence was 0.9% and exclusively minimal background retinopathy with 100% remission in re-screenings. Thus, screening at this age does not seem to have significant clinical relevance. We propose more individualized screening selection before the age of 15.

Interaction analysis of systolic blood pressure and glycosylated hemoglobin in diabetic retinopathy: A Chinese sample

Background: The objective of this study was to evaluate (1) the association of blood pressure (BP) profiles and glucose profiles with diabetic retinopathy (DR) and (2) the interaction between BP profiles and glucose profiles in DR in a Chinese sample.

Methods: This was a cross-sectional study of 984 DR patients. Demographic data, BP profiles, glucose profiles, renal function parameters, and medical histories were recorded. All the participants underwent testing for DR with digital nonmydriatic fundus photography and image analysis, using a standardized protocol. A multiple variable logistic regression (MLR) was employed to detect the associations and interactions of BP profiles and glucose profiles with DR.

Results: Systolic blood pressure (SBP) and glycated hemoglobin (HbA1c) were significantly correlated with DR ([Formula: see text] for SBP, [Formula: see text]; [Formula: see text] for HbA1c, [Formula: see text]). An interaction between SBP and HbA1c was detected in a multiple logistic regression (MLR) model after adjustment for relevant potential confounders ([Formula: see text], [Formula: see text]).

Conclusion: The present study suggested that SBP and HbA1c were independently and significantly associated with DR and that SBP interacted with HbA1c to impact on DR.

Incidence of sight-threatening diabetic retinopathy in people with Type 2 diabetes mellitus and numbers needed to screen: a systematic review

AIM

To investigate the incidence of sight-threatening diabetic retinopathy in Type 2 diabetes mellitus.

BACKGROUND

In most countries, yearly or biennial screening intervals for diabetic retinopathy in people with Type 2 diabetes are recommended. Fewer screening sessions reduce the effort required of people with Type 2 diabetes and reduce healthcare costs.

METHODS

We conducted a search of PubMed, Embase, Web of Science and the COCHRANE Library for studies published betweeen 1 January 2000 and 1 January 2017. Eligible studies were those that included general populations of >100 people with Type 2 diabetes mellitus. Additional study population criteria were absence of moderate diabetic retinopathy or more severe diabetic retinopathy at last screening session and at least two gradable retinal screening sessions. Outcomes of interest in the included studies were moderate and severe non-proliferative diabetic retinopathy (R2), proliferative diabetic retinopathy (R3) or maculopathy (M1), collectively known as sight-threatening or referable diabetic retinopathy.

RESULTS

A total of 17 studies were included. In people with Type 2 diabetes without or with only mild diabetic retinopathy at baseline, the average incidence rates of sight-threatening diabetic retinopathy were ~1 per 100 person-years and ~8 per 100 person-years, respectively. The average numbers needed to screen to detect one case of sight-threatening diabetic retinopathy were 175 and 19 in people without and with mild retinopathy at last screening, respectively.

CONCLUSION

In people with Type 2 diabetes without retinopathy at last screening, the incidence of severe sight-threatening retinopathy at the subsequent screening session was low. In people with mild retinopathy, progression to sight-threatening diabetic retinopathy was nearly 10-fold higher. This review supports lengthening of the screening interval of patients with Type 2 diabetes without retinopathy at last screening session.

Retinopathy among Chinese subjects with type 2 diabetes mellitus in Shanghai: A community-based follow-up study

OBJECTIVE

To determine the incidence, progression, and regression rates of diabetic retinopathy (DR), as well as their associated factors, in Chinese type 2 diabetic patients.

METHODS

Diabetic patients who participated in a previous survey were recruited for a 1-year follow-up study. Nonmydriatic fundus photographs were acquired to assess the severity of DR as per the International Clinical Diabetic Retinopathy Disease Severity Scale (2002). Factors that potentially influence DR outcomes, including its incidence, progression, and regression, were identified via statistical analyses.

RESULTS

We initially recruited 2453 subjects, among whom 2331 were followed and included in the final analysis. The incidences of new and progressed (ie, ≥2 scale steps) DR were 10.6% and 6.1%, respectively. Moreover, 7.3% of patients with established DR at baseline experienced complete regression. Multivariate logistic regression analysis revealed that high glycosylated haemoglobin (HbA1c) (odds ratio [OR] = 1.50, P = .021) and hyperlipidaemia (OR = 1.46, P = .025) were independent predictors of DR development, high HbA1c (OR = 4.16, P = .027) and macroalbuminuria (OR = 5.60, P = .010) predicted DR progression, and low HbA1c (OR = 0.20, P = .001) and low triglyceride levels (OR = 0.34, P = .026) were associated with DR regression.

CONCLUSIONS

Albumin and HbA1c levels should be closely monitored as signs of progressive retinal damage in diabetic subjects. Optimized control of glucose and triglyceride levels is vital for reducing the incidence of DR or promoting its regression in afflicted patients.

Incidence and progression of diabetic retinopathy: a systematic review

Diabetic retinopathy is a leading cause of vision impairment and blindness. We systematically reviewed studies published from Jan 1, 1980, to Jan 7, 2018, assessed the methodological quality, and described variations in incidence of diabetic retinopathy by region with a focus on population-based studies that were conducted after 2000 (n=8, including two unpublished studies). Of these eight studies, five were from Asia, and one each from the North America, Caribbean, and sub-Saharan Africa. The annual incidence of diabetic retinopathy ranged from 2·2% to 12·7% and progression from 3·4% to 12·3%. Progression to proliferative diabetic retinopathy was higher in individuals with mild disease compared with those with no disease at baseline. Our Review suggests that more high-quality population-based studies capturing data on the incidence and progression of diabetic retinopathy with stratification by age and sex are needed to consolidate the evidence base. Our data is useful for conceptualisation and development of major public health strategies such as screening programmes for diabetic retinopathy.

A genome-wide association study suggests new evidence for an association of the NADPH Oxidase 4 (NOX4) gene with severe diabetic retinopathy in type 2 diabetes

Purpose

Diabetic retinopathy is the most common eye complication in patients with diabetes. The purpose of this study is to identify genetic factors contributing to severe diabetic retinopathy.

Methods

A genome‐wide association approach was applied. In the Genetics of Diabetes Audit and Research in Tayside Scotland (GoDARTS) datasets, cases of severe diabetic retinopathy were defined as type 2 diabetic patients who were ever graded as having severe background retinopathy (Level R3) or proliferative retinopathy (Level R4) in at least one eye according to the Scottish Diabetic Retinopathy Grading Scheme or who were once treated by laser photocoagulation. Controls were diabetic individuals whose longitudinal retinopathy screening records were either normal (Level R0) or only with mild background retinopathy (Level R1) in both eyes. Significant Single Nucleotide Polymorphisms (SNPs) were taken forward for meta‐analysis using multiple Caucasian cohorts.

Results

Five hundred and sixty cases of type 2 diabetes with severe diabetic retinopathy and 4,106 controls were identified in the GoDARTS cohort. We revealed that rs3913535 in the NADPH Oxidase 4 (NOX4) gene reached a p value of 4.05 × 10⁻⁹. Two nearby SNPs, rs10765219 and rs11018670 also showed promising p values (p values = 7.41 × 10⁻⁸ and 1.23 × 10⁻⁸, respectively). In the meta‐analysis using multiple Caucasian cohorts (excluding GoDARTS), rs10765219 and rs11018670 showed associations for diabetic retinopathy (p = 0.003 and 0.007, respectively), while the p value of rs3913535 was not significant (p = 0.429).

Conclusion

This genome‐wide association study of severe diabetic retinopathy suggests new evidence for the involvement of the NOX4 gene.

Could Intensive Blood Pressure Control Really Reduce Diabetic Retinopathy Outcomes? Evidence from Meta-Analysis and Trial Sequential Analysis from Randomized Controlled Trials

INTRODUCTION

To explore the accumulated evidence concerning the effect of intensive blood pressure control on the incidence and progression of diabetic retinopathy (DR), proliferative diabetic retinopathy (PDR) and macular edema (ME).

METHODS

A number of electronic databases were searched including PubMed, EMBASE, CINAHL, Cochrane Library, conferences and proceedings. Randomized controlled trials comparing intensive blood pressure targets with conventional blood pressure targets in patients with type 2 diabetes were included. The definition of intensive versus conventional blood pressure targets was from the pertinent original studies. Meta-analyses and trial sequential analyses of randomized trials were analyzed in STATA.

RESULTS

Eight trials randomizing 6989 patients were assessed and reviewed in full text; 3749 vs. 3240 were in each arm (intensive vs. conventional). All trials had a low risk of bias. Intensive blood pressure control supported a 17% reduction in the incidence of DR (relative risk 0.83, 95% confidence interval 0.72-0.95). Trial sequential analyses confirmed that sufficient evidence indicated a relative risk reduction above 17% for the incidence of DR when intensive blood pressure control was targeted. Heterogeneity was absent (I² = 0%; P = 0.56). No statistically significant effect was found for intensive blood pressure targeting on the progress of DR (relative risk 0.94, 95% confidence interval 0.81-1.08). TSA showed that insufficient evidence had been found, although the Z value line appeared to have a tendency of approaching the futility boundaries. There were also no statistically significant effects on the incidence of PDR and ME (TSA-adjusted CI 0.84-1.12).

CONCLUSION

Intensive blood pressure control reduced the relative risk of incidence of DR by 17%. The available data were insufficient to prove or refute a relative risk reduction for the progression of DR or incidence of PDR and ME at a magnitude of 15%.

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.

Ophthalmic and clinical factors that predict four-year development and worsening of diabetic retinopathy in type 1 diabetes

AIMS

To investigate the role of ophthalmic imaging markers - namely retinal thickness measures and corneal nerve morphology - in predicting four-year development and worsening of diabetic retinopathy (DR) in type 1 diabetes (T1DM).

METHODS

126 eyes of 126 participants with T1DM were examined at baseline and after four years. Diabetic retinopathy (DR) was graded using the Early Treatment Diabetic Retinopathy Study scale. HbA_1c, nephropathy, neuropathy, cardiovascular factors, and retinal thickness using optical coherence tomography (OCT) and corneal nerve fiber length (CNFL) using corneal confocal microscopy at baseline were assessed by univariate and step-wise multiple logistic regression, and their diagnostic capabilities for single and combined measures.

RESULTS

Four-year development of DR was 19% (13 of 68 without DR at baseline). Worsening of DR was seen in 43% (25 of 58 with DR at baseline). When adjusted for potential confounders, a lower CNFL (AUC=0.637, p=0.040, 64% sensitivity and 64% specificity at 14.9mm/mm² cut-off), higher triglycerides (AUC=0.669, p=0.012, 64% sensitivity, 62% specificity at 0.85mmol/L) and an elevated vibration threshold (AUC=0.708, p=0.002, 96% sensitivity, 40% specificity at 3.55Hz) were significant predictors for four-year worsening of DR.

CONCLUSIONS

Reduced CNFL, elevated vibration perception threshold and higher triglycerides can predict future worsening of DR.

Delayed follow-up in patients with diabetic retinopathy in South India: Social factors and impact on disease progression

Purpose:

To identify social factors associated with delayed follow-up in South Indian patients with diabetic retinopathy (DR) and to study DR progression during the delayed follow-up period.

Materials and Methods:

In this cross-sectional study, 500 consecutive patients with DR returning after greater than twice the advised follow-up period were identified from a tertiary referral center in South India. A previously validated 19-item questionnaire was administered to study patients to assess causes for the follow-up delay. Patient demographics, DR status, and treatment plan were recorded at the study visit and the visit immediately before the delay. The eye with the most severe disease was included in the analysis.

Results:

Complete data were available for 491 (98.2%) patients. Among these, 248 (50.5%) cited “my eyes were okay at the time,” 201 (41.0%) cited “no attender to accompany me,” and 190 (38.6%) cited “financial cost” as causes of the follow-up delay. Those with vision-threatening DR (VTDR, n = 233) predominantly reported “financial cost” (47% vs. 32%, P = 0.001), whereas those with non-VTDR more frequently reported “my eyes were okay at the time” (58% vs. 42%, P = 0.001). Evidence of disease progression from non-VTDR to VTDR was seen in 67 (26%) patients. Almost 1/3^rd (29%) of patients who were previously advised regular examination required additional intervention.

Conclusion:

Many patient-level factors affect poor compliance with follow-up in DR, and these factors vary by disease severity. Targeting these barriers to care through patient education and clinic procedures may promote timely follow-up and better outcomes in these patients.

Influence of serum lipids on the incidence and progression of diabetic retinopathy and macular oedema: Sankara Nethralaya Diabetic Retinopathy Epidemiology And Molecular genetics Study-II

IMPORTANCE

The importance of lipids on incidence and progression of diabetic retinopathy has not been studied in the Indian population.

BACKGROUND

To elucidate the influence of serum lipid control on the incidence and progression of diabetic retinopathy and diabetic macular oedema in subjects with type 2 diabetes.

DESIGN

Population-based longitudinal observational study in a hospital setting.

PARTICIPANTS

Eight hundred ninety subjects were examined at baseline and follow-up.

METHODS

Diabetic retinopathy was graded per Modified Early Treatment Diabetic Retinopathy Study scales; 45°, 4-field dilated stereoscopic digital photography was performed with an additional 30°, 7-field for those who had retinopathy. Macular oedema was evaluated per Proposed International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Disease Severity Scales.

MAIN OUTCOME MEASURES

Association of serum lipids and incidence and progression of diabetic retinopathy.

RESULTS

Poor control of total cholesterol was associated with the incidence of sight-threatening retinopathy (odds ratio = 7.2 [95% confidence interval: 1.5-34.3], P = 0.012) and macular oedema (odds ratio = 5.5 [95% confidence interval: 1.4-27.4], P = 0.037) after adjusting for potential confounders. Poor control of triglycerides was associated with progression to proliferative diabetic retinopathy (odds ratio = 3.2 [95% confidence interval: 1.1-10.5], P = 0.048). Risk for incident macular oedema (P = 0.041) and progression to proliferative diabetic retinopathy (P = 0.028) was greater when all lipid types were abnormal.

CONCLUSIONS AND RELEVANCE

Poor control of lipids is a risk factor for incidence of and progression to late stages of retinopathy. Abnormal levels of all lipid types are associated with risk of incident macular oedema and progression to proliferative diabetic retinopathy.

Plasma miR-21 expression: an indicator for the severity of Type 2 diabetes with diabetic retinopathy

To investigate the roles of plasma miR-21 in the pathogenic process of Type 2 diabetes (T2D) with diabetic retinopathy (DR). T2D patients included patients without DR (NDR) group, patients with non-proliferative/background DR (BDR) group and patients with proliferative DR (PDR) group. Healthy individuals served as control group. Fasting plasma glucose (FPG), glycosylated haemoglobin (HbA1c), triacylglycerol (TG), total cholesterol (TC), urine creatinine (Cr), fasting blood glucose (FBG), blood urea nitrogen (BUN), low-density lipoprotein cholesterol (LDL-C), fasting insulin (FINS) and plasma miR-21 expression were measured. Quantitative real-time PCR (qRT-PCR) was applied to detect miR-21 expression. Pearson analysis was used to conduct correlation analysis and receiver operating characteristic (ROC) curve was used to analyse the diagnostic value of miR-21 in T2D with DR. Compared with the control group, FBG and HbA1c increased in the NDR group; compared with the control and NDR groups, disease course, HbA1c, FPG levels and homoeostasis model assessment of insulin resistance (HOMA-IR) were increased in the BDR and PDR groups; and compared with the BDR group, disease course, HbA1c and FPG levels were higher in the PDR group. miR-21 expression was higher in the BDR group than the control group, and higher in the PDR group than the BDR group. miR-21 expression was positively related with disease course, HbA1C, FPG and HOMA-IR, and had diagnostic value for T2D with DR and PDR. The plasma miR-21 expression was increased in the development of T2D with DR and can be used as an indicator for the severity of T2D with DR.

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.

Epidemiology of diabetic retinopathy, diabetic macular edema and related vision loss

Diabetic retinopathy (DR) is a leading cause of vision-loss globally. Of an estimated 285 million people with diabetes mellitus worldwide, approximately one third have signs of DR and of these, a further one third of DR is vision-threatening DR, including diabetic macular edema (DME). The identification of established modifiable risk factors for DR such as hyperglycemia and hypertension has provided the basis for risk factor control in preventing onset and progression of DR. Additional research investigating novel risk factors has improved our understanding of multiple biological pathways involved in the pathogenesis of DR and DME, especially those involved in inflammation and oxidative stress. Variations in DR prevalence between populations have also sparked interest in genetic studies to identify loci associated with disease susceptibility. In this review, major trends in the prevalence, incidence, progression and regression of DR and DME are explored, and gaps in literature identified. Established and novel risk factors are also extensively reviewed with a focus on landmark studies and updates from the recent literature.

Epidemiology of diabetic retinopathy, diabetic macular edema and related vision loss

Diabetic retinopathy (DR) is a leading cause of vision-loss globally. Of an estimated 285 million people with diabetes mellitus worldwide, approximately one third have signs of DR and of these, a further one third of DR is vision-threatening DR, including diabetic macular edema (DME). The identification of established modifiable risk factors for DR such as hyperglycemia and hypertension has provided the basis for risk factor control in preventing onset and progression of DR. Additional research investigating novel risk factors has improved our understanding of multiple biological pathways involved in the pathogenesis of DR and DME, especially those involved in inflammation and oxidative stress. Variations in DR prevalence between populations have also sparked interest in genetic studies to identify loci associated with disease susceptibility. In this review, major trends in the prevalence, incidence, progression and regression of DR and DME are explored, and gaps in literature identified. Established and novel risk factors are also extensively reviewed with a focus on landmark studies and updates from the recent literature.

Epidemiology of diabetic retinopathy, diabetic macular edema and related vision loss

Diabetic retinopathy (DR) is a leading cause of vision-loss globally. Of an estimated 285 million people with diabetes mellitus worldwide, approximately one third have signs of DR and of these, a further one third of DR is vision-threatening DR, including diabetic macular edema (DME). The identification of established modifiable risk factors for DR such as hyperglycemia and hypertension has provided the basis for risk factor control in preventing onset and progression of DR. Additional research investigating novel risk factors has improved our understanding of multiple biological pathways involved in the pathogenesis of DR and DME, especially those involved in inflammation and oxidative stress. Variations in DR prevalence between populations have also sparked interest in genetic studies to identify loci associated with disease susceptibility. In this review, major trends in the prevalence, incidence, progression and regression of DR and DME are explored, and gaps in literature identified. Established and novel risk factors are also extensively reviewed with a focus on landmark studies and updates from the recent literature.

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

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