Current epidemiology of diabetic retinopathy and diabetic macular edema

EFFECTS OF INTRAVITREAL RANIBIZUMAB AND BEVACIZUMAB ON THE RETINAL VESSEL SIZE IN DIABETIC MACULAR EDEMA

PURPOSE

The goal of this study was to assess the effects of a single injection of intravitreal ranibizumab (RAN) or bevacizumab (BEV) on the retinal vessel size in eyes with diabetic macular edema.

MATERIALS AND METHODS

In total, 32 patients were enrolled in the RAN group, and 30 patients were included in BEV group. Each of these groups was also subdivided into two others groups: a study group and a control group. The study groups were composed of the injected eyes, whereas the noninjected fellow eyes served as the control groups. The patients underwent complete ophthalmic examinations, including optical coherence tomography and fundus fluorescein angiography, and the primary outcome measures included the central retinal artery equivalent, central retinal vein equivalent, and artery-to-vein ratio.

RESULTS

In the RAN study group (n = 32), the preinjection mean central retinal artery equivalent (175.42 μm) decreased to 169.01 μm after 1 week, and to 167.47 μm after 1 month (P < 0.001), whereas the baseline central retinal vein equivalent (235.29 μm) decreased initially to 219.90 μm after 1 week, and to 218.36 μm after 1 month (P < 0.001). In the BEV study group (n = 30), the preinjection central retinal artery equivalent (150.21 μm) decreased to 146.25 μm after 1 week, and to 145.89 μm after 1 month (P < 0.001); whereas the baseline central retinal vein equivalent (211.87 μm) decreased initially to 204.59 μm after 1 week and was 205.24 μm after 1 month (P < 0.001). The preinjection artery-to-vein ratio values changed significantly (P = 0.001) after 1 week and after 1 month in the RAN group, but no significant alteration in the artery-to-vein ratio was observed in the BEV group (P = 0.433). In both the RAN (n = 32) and BEV (n = 30) control groups, none of the 3 parameters changed throughout the study period, when compared with the baseline.

CONCLUSION

The results of this study showed that both RAN and BEV injections significantly constricted the retinal blood vessel diameters.

Prevalence, risk factors and burden of diabetic retinopathy in China: a systematic review and meta-analysis

Background

Diabetic retinopathy (DR), the primary retinal vascular complication of diabetes mellitus (DM), is a leading cause of vision impairment and blindness in working-age population globally. Despite mounting concerns about the emergence of DM as a major public health problem in the largest developing country, China, much remains to be understood about the epidemiology of DR. We aimed to investigate the prevalence of and risk factors for DR, and estimate the burden of DR in China in 2010.

Methods

China National Knowledge Infrastructure (CNKI), Wanfang, Chinese Biomedicine Literature Database (CBM-SinoMed), PubMed, Embase and Medline were searched for studies that reported the prevalence of and risk factors for DR in Chinese population between 1990 and 2017. A random-effects meta-analysis model was adopted to pool the overall prevalence of DR. Variations in the prevalence of DR in different age groups, DM duration groups and settings were assessed by subgroup meta-analysis and meta-regression. Odds ratios (ORs) of major risk factors were pooled using random-effects meta-analysis. The number of people with DR in 2010 was estimated by multiplying the age-specific prevalence of DR in people with DM with the corresponding number of people with DM in China. Finally, the national number of people with DR was distributed into six geographic regions using a risk factor-based model.

Results

A total of 31 studies provided information on the prevalence of DR and 21 explored potential risk factors for DR. The pooled prevalence of any DR, nonproliferative DR (NPDR) and proliferative DR (PDR) was 1.14% (95% CI = 0.80-1.52), 0.90% (95% CI = 0.56-1.31) and 0.07% (95% CI = 0.02-0.14) in general population; In people with DM, the pooled prevalence rates were 18.45% (95% CI = 14.77-22.43), 15.06% (95% CI = 11.59-18.88) and 0.99% (95% CI = 0.40-1.80) for any DR, NPDR and PDR, respectively. The prevalence of any DR in DM patients peaked between 60 and 69 years of age, and increased steeply with the duration of DM. DM patients residing in rural China were at a higher risk to have DR than those in urban areas. In addition, insulin treatment, elevated FBG level and higher HbA1c concentration were confirmed to be associated with a higher prevalence of DR in people with DM, with meta-ORs of 1.99 (95% CI = 1.34-2.95), 1.33 (95% CI = 1.12-1.59) and 1.15 (95% CI = 1.09-1.20) respectively. In 2010, a total of 13.16 million (95% CI = 8.95-18.00) Chinese aged 45 years and above were living with DR, among whom the most were in South Central China and the least were in Northwest China.

Conclusions

DR has become a serious public health problem in China. Optimal screening of and interventions on DR should be implemented. Improved epidemiological studies on DR are still required.

Diabetic retinopathy in patients with diabetic foot syndrome in South India

Purpose

The purpose was to study the retinopathy status in diabetic patients with a risk of diabetic foot (DF) syndrome visiting a tertiary care hospital in South India.

Methods

In this cross sectional study all patients with diabetes mellitus (DM) with a risk of DF syndrome, visiting a tertiary care hospital during the study period, underwent an ophthalmological evaluation for documentation of their retinopathy status.

Results

One hundred and eighty-two patients diagnosed to have a risk profile for DF syndrome were included in the study. Their mean age was 59.28 years and 75.27% were males. The mean duration of Type 1 and Type 2 variants of DM was 14.9 years and 10.9 years, respectively. Of the 182 patients, 67.58% had retinopathy changes. Proliferative diabetic retinopathy (DR) constituted 17.88% of the total patients with retinopathy. An increased presence of retinopathy in patients with an increased risk grade of DF was found significant by the Chi-square test (P < 0.001).

Conclusion

Our study found an increased presence of DR in a South Indian cohort with DF syndrome. The severity of retinopathy was greater in patients with higher grades of risk for DF. The establishment of an association between DR and DF syndrome will help in developing an integrated management strategy for these two debilitating consequences of diabetes.

Microaneurysm detection using fully convolutional neural networks

BACKROUND AND OBJECTIVES

Diabetic retinopathy is a microvascular complication of diabetes that can lead to sight loss if treated not early enough. Microaneurysms are the earliest clinical signs of diabetic retinopathy. This paper presents an automatic method for detecting microaneurysms in fundus photographies.

METHODS

A novel patch-based fully convolutional neural network with batch normalization layers and Dice loss function is proposed. Compared to other methods that require up to five processing stages, it requires only three. Furthermore, to the best of the authors' knowledge, this is the first paper that shows how to successfully transfer knowledge between datasets in the microaneurysm detection domain.

RESULTS

The proposed method was evaluated using three publicly available and widely used datasets: E-Ophtha, DIARETDB1, and ROC. It achieved better results than state-of-the-art methods using the FROC metric. The proposed algorithm accomplished highest sensitivities for low false positive rates, which is particularly important for screening purposes.

CONCLUSIONS

Performance, simplicity, and robustness of the proposed method demonstrates its suitability for diabetic retinopathy screening applications.

Less Expansion of Short-Pulse Laser Scars in Panretinal Photocoagulation for Diabetic Retinopathy

Purpose

To compare the expansion rates of laser photocoagulation scars between the conventional laser and short-pulse laser using fundus autofluorescence (FAF).

Methods

Retrospective chart review. Conventional laser was performed on 6 eyes of 6 patients, and short-pulse laser was performed on 11 eyes of 8 patients with diabetic retinopathy. FAF images were obtained by Optos® 200Tx (Optos, Dunfermline, Scotland, UK) at 1, 3, 6, and 12 months after treatment. The average area of 20 photocoagulation scars was measured by using ImageJ software. The expansion rates were calculated from the proportion of the averaged area against the optic disc area. Regression of retinopathy and central macular thickness were also evaluated.

Results

The expansion rates of the conventional laser scars compared with the size at 1 month after treatment were 1.12 ± 0.08 (3 M), 1.27 ± 0.12 (6 M), and 1.39 ± 0.11 (12 M). The expansion rates of the short-pulse laser scars were 1.04 ± 0.05 (3 M), 1.09 ± 0.04 (6 M), and 1.13 ± 0.05 (12 M). The expansion rates of the short-pulse laser were significantly lower than those of the conventional laser (p < 0.01).

Conclusion

FAF images were useful to evaluate the changes in the photocoagulation scar sizes. The scars with the short-pulse laser showed lower expansion rates than those of the conventional laser.

The prevalence and systemic risk factors of diabetic macular edema: a cross-sectional study from Turkey

Background

The aim of this study was to evaluate the prevalence of diabetic macular edema (DME) utilizing optical coherence tomography (OCT), and to clarify the effects of the systemic findings and risk factors on the development of DME.

Methods

This cross-sectional study was conducted in the departments of ophthalmology and endocrinology at the Dokuz Eylul University School of Medicine in Izmir, Turkey. The demographics, type and duration of diabetes mellitus, treatment modality, smoking and alcohol consumption habits, as well as the systemic blood pressure, renal functional tests, hemoglobulin A1c level, serum lipid profile, and 24-h urine albumin level were noted and statistically analyzed. The relationships between the systemic findings and DME were studied.

Results

Four-hundred and thirteen eyes of 413 diabetic patients who were examined between January 2011 and July 2012 were enrolled in this study. The prevalence of DME was 15.3% among the patients. The males exhibited DME significantly more frequently than the females (p = 0.031), and the duration of diabetes was significantly longer in those patients with DME (p < 0.001). Those patients without DME frequently used antihyperlipidemic drugs and had a higher level of high density lipoprotein cholesterol (p = 0.040 and p = 0.046, respectively). The patient’s alcohol consumption, nephropathy, neuropathy, previous cataract surgery, severity of diabetic retinopathy, and insulin usage were statistically significant factors with regard to the DME prevalence.

Conclusions

This study demonstrated the prevalence of DME in Turkey by utilizing OCT. The development of DME can be avoided or limited and the response to treatment may be improved by the regulation of the DME risk factors.

Clinical Decision-Making when Treating Diabetic Macular Edema Patients with Dexamethasone Intravitreal Implants

Diabetes mellitus (DM) is a metabolic disease frequently associated with comorbidities that include diabetic macular edema (DME). The current medical approach to treating DME involves intravitreal injections with either anti-vascular endothelial growth factors or steroids. However, the burden associated with intravitreal injections and DM-derived complications is high, underlining the need to find optimal treatment regimens. In this article we describe the considerations we apply when treating DME patients with dexamethasone intravitreal implants (Ozurdex®), particularly those that influence the clinical decision-making process during the follow-up period. These considerations are based both on the available medical literature and on our clinical experience following the use of these implants in this type of patient, the goal being to optimize the number of injections and the clinical outcome of this therapy. We also provide a general overview of the pathophysiology of DME, highlighting the inflammatory component as a rationale to use steroids in these patients.

Physical activity, visual impairment, and eye disease

Numerous studies have demonstrated physical activity is a strong factor in overall health and well-being, and a growing body of literature, reviewed herein, suggests that several eye conditions, including glaucoma, age-related macular degeneration, and diabetic retinopathy, are associated with lower activity levels. Likewise, physical activity levels are lower in persons with worse vision. Research in this area has utilized both self-reported physical activity measures as well as objective measures of activity (i.e., accelerometers), each of which have their own strengths and limitations. Putative mechanisms explaining the association of various eye conditions with physical activity are discussed. It is possible that activity restriction occurs as a downstream consequence of eye disease/visual impairment, that activity restriction causes eye disease/visual impairment, or that causality is bidirectional; evidence supporting each of these theories is put forth. An improved understanding of the relationship between physical activity and eye disease will highlight potential secondary health risks resulting from eye disease, and can help determine whether activity might serve as a readily available preventative measure to prevent specific eye conditions.

'Statins in retinal disease'

Statins are known for their blood cholesterol-lowering effect and are widely used in patients with cardiovascular and metabolic diseases. Research over the past three decades shows that statins have diverse effects on different pathophysiological pathways involved in angiogenesis, inflammation, apoptosis, and anti-oxidation, leading to new therapeutic options. Recently, statins have attracted considerable attention for their immunomodulatory effect. Since immune reactivity has been implicated in a number of retinal diseases, such as uveitis, age-related macular degeneration (AMD) and diabetic retinopathy, there is now a growing body of evidence supporting the beneficial effects of statins in these retinopathies. This review evaluates the relationship between statins and the pathophysiological basis of these diseases, focusing on their potential role in treatment. A PubMed database search and literature review was conducted. Among AMD patients, there is inconsistent evidence regarding protection against development of early AMD or delaying disease progression; though they have been found to reduce the risk of developing choroidal neovascular membranes (CNV). In patients with retinal vein occlusion, there was no evidence to support a therapeutic benefit or a protective role with statins. In patients with diabetic retinopathy, statins demonstrate a reduction in disease progression and improved resolution of diabetic macular oedema (DMO). Among patients with uveitis, statins have a protective effect by reducing the likelihood of uveitis development.

Differential effect of body mass index on the incidence of diabetes and diabetic retinopathy in two Asian populations

AIMS

To examine the association of body mass index (BMI) with the incidence of diabetes mellitus (DM) and diabetic retinopathy (DR) in Asians.

METHODS

We analysed data from 4101 adults (Malay, n = 1901 and Indian, n = 2200) who participated in the baseline (2004-2009) and 6-year follow-up (2011-2015) of two independent population-based studies with similar methodology in Singapore. BMI was categorised into normal (<25 kg/m²), overweight (25-29.9 kg/m²) and obese (≥30 kg/m²). DM was diagnosed as random plasma glucose ≥200 mg/dL, HbA_1c ≥6.5% or self-reported physician diagnosed DM. DR was assessed from retinal photographs graded using a standard protocol. The associations of baseline BMI with incident DM and DR was examined using multivariable poisson regression models adjusting for potential confounders including duration of DM, family history of DM and HbA_1c.

RESULTS

The incidence of DM was 12.8% and among 1586 participants with DM, the incidence of DR was 17.6% over a median follow-up period of 6.2 years. Compared to those with BMI < 25, the relative risk (95% confidence interval) of incident DM was 1.77 (1.36-2.29) for overweight and 2.01 (1.50-2.71) for obese (p trend < 0.001). Relative risk of DR was 0.80 (0.59-1.09) for overweight and 0.60 (0.39-0.92) for obese (p trend = 0.02). In analyses stratified by ethnicity, similar pattern of associations with DM and DR were observed in both ethnicities.

CONCLUSION

Our results suggest that, overweight and obesity increased the 6-year risk of DM but decreased the 6-year risk of DR in these Asian populations.

Screening for vision-threatening diabetic retinopathy in South India: comparing portable non-mydriatic and standard fundus cameras and clinical exam

PurposeTo evaluate the sensitivity and specificity of a portable non-mydriatic fundus camera to diagnose vision-threatening diabetic retinopathy (VTDR).Patients and methodsA prospective, single-site, comparative instrument validation study was undertaken at the Aravind Eye Care System. Overall, 155 subjects with and without diabetes were recruited. Images from 275 eyes were obtained with the (1) non-mydriatic Smartscope, (2) mydriatic Smartscope, and (3) mydriatic table-top camera of the macular, nasal, and superotemporal fields. A retina specialist performed a dilated fundus examination (DFE), (reference standard). Two masked retina specialists graded the images. Sensitivity and specificity to detect VTDR with the undilated Smartscope was calculated compared to DFE.ResultsGraders 1 and 2 had a sensitivity of 93% (95% confidence interval (CI): 87-97%) and 88% (95% CI: 81-93%) and a specificity of 84% (95% CI: 77-89%) and 90% (95% CI: 84-94%), respectively, in diagnosing VTDR with the undilated Smartscope compared to DFE. Compared with the dilated Topcon images, graders 1 and 2 had sensitivity of 88% (95% CI: 81-93%) and 82% (95% CI: 73-88%) and specificity of 99% (95% CI: 96-100%) and 99% (95% CI: 95-100%).ConclusionsRemote graders had high sensitivity and specificity in diagnosing VTDR with undilated Smartscope images, suggesting utility where portability is a necessity.

COMBINED INTRAVITREAL RANIBIZUMAB AND ORAL SUPPLEMENTATION WITH DOCOSAHEXAENOIC ACID AND ANTIOXIDANTS FOR DIABETIC MACULAR EDEMA: Two-Year Randomized Single-Blind Controlled Trial Results

PURPOSE

To assess the 2-year effectiveness of intravitreal ranibizumab combined with a dietary supplement rich in docosahexaenoic acid (DHA) plus antioxidants in 62 patients with diabetic macular edema.

METHODS

In a randomized single-blind controlled study, 33 subjects (42 eyes) received intravitreal ranibizumab alone and 29 (34 eyes) combined with DHA (1,050 mg/day). Monthly ranibizumab (0.5 mg) was given for the first 4 months followed by on as-needed treatment.

RESULTS

At 24 months, the difference between groups in the decrease of central subfield macular thickness was significant in favor of the DHA supplementation group (95% confidence interval of the difference 7.20-97.656; P = 0.024), although improvement in best-corrected visual acuity measured in the Early Treatment Diabetic Retinopathy Study letters did not reach statistical significance (95% confidence interval 5.4-11.2, P < 0.66). At 24 months, gains of >5 and >10 letters were significantly higher in the DHA supplementation group as compared with controls when the worse and better seeing eyes were considered but other differences at 12 months and 24 months were not found.

CONCLUSION

Intravitreal ranibizumab combined with DHA supplementation reduced central subfield macular thickness after 2 years of follow-up as compared with ranibizumab alone in patients with diabetic macular edema. This anatomical improvement was accompanied by a trend for an amelioration of vision.

Aflibercept for clinically significant diabetic macular edema: 12-month results in daily clinical practice

Purpose

To assess the effectiveness and safety of intravitreal aflibercept in clinically significant diabetic macular edema (DME) in daily clinical practice.

Methods

Prospective, open-label, single-center study. Anti-vascular endothelial growth factor naïve patients with clinically significant DME received intravitreal injections of aflibercept 2 mg, five monthly doses followed by a fixed schedule every 2 months for 12 months. The mean change in best-corrected visual acuity (BCVA) (Early Treatment Diabetic Retinopathy Study [ETDRS] letters) was the primary outcome.

Results

The mean BCVA improved significantly as compared with baseline at 12 months of treatment (47.3 [14.2] vs 62.2 [13.9] ETDRS letters, P<0.001). Significant improvement in BCVA was already observed at visit 2 after the loading doses of aflibercept. At 12 months, gains in ETDRS letters were documented in all eyes (100%), with gains ≥10 letters in 89.6%, ≥15 letters in 65.5%, and ≥20 letters in 6.9% (n=2). A significant reduction in central macular thickness from a mean of 460.5 (11.8) μm at baseline to 229.0 (43.8) μm at 12 months (P<0.001) was observed. Significant reductions of central macular thickness were already observed after the loading doses and continued lowering throughout the study period. No adverse events occurred.

Conclusion

Aflibercept as a first-line therapy was effective and well tolerated for treating clinically significant DME in naïve patients in daily practice. Successful results in terms of improvement of visual and reduction in central macular thickness contribute to provide evidence for the positioning of aflibercept as a first-line indication of newly diagnosed clinically significant DME.

Prevalence and risk factors for diabetic retinopathy in 17 152 patients from the island of Funen, Denmark

PURPOSE

This study aims to estimate the prevalence and risk factors of diabetic retinopathy (DR) in patients enrolled in a large Danish quality-assuring database for diabetes: the Funen Diabetes Database (FDDB).

METHODS

All patients with type 1 (T1DM) and type 2 DM (T2DM) diabetes mellitus (DM) were included in a cross-sectional study. The level of DR per patient was determined based on the eye with highest level of DR. All ocular and non-ocular data were extracted at the latest examination that corresponded to the most recent DR-grading data.

RESULTS

Data from 17 152 patients were analysed; 83.1% had T2DM. Prevalence of DR was 23.8% (T1DM: 54.3%, T2DM: 21.2%). T1/T2DM patients were statistically significantly different regarding age, duration of diabetes, BMI, systolic blood pressure (BP), cholesterol, LDL cholesterol, HDL cholesterol, triglyceride, s-creatinine and u-albumin (p < 0.001 for all). Increasing level of DR showed statistically significant association with age, duration of diabetes, systolic BP, HbA1c, s-creatinine and u-albumine with increasing level of DR (all are p < 0.001) both T1DM/T2DM patients.

CONCLUSION

The patients in FDDB had good systemic control with median values of BP, serum lipids, cholesterol and HbA1c all close to or below national guidelines at the time of data extraction, but still a high level of DR was found in this cohort. DR was more common in patients with T1DM than T2DM, but as T2DM patients are more numerous, their level of DR despite acceptable control is still concerning. Most important associated factors for higher levels of DR were age, duration of diabetes, HbA1c, s-creatinine and u-albumine.

Effects of Intravitreal Aflibercept on Galectin-1 and Vascular Endothelial Growth Factor-A Plasma Levels in Patients with Diabetic Retinopathy

PURPOSE

To analyze the interaction between aflibercept and galectin-1 and evaluate the plasma levels of galectin-1 and vascular endothelial growth factor (VEGF)-A after intravitreal injection of aflibercept in patients with diabetic retinopathy (DR).

METHODS

Interaction of galectin-1 with aflibercept was determined via immunoprecipitation. Seventeen patients with type 2 diabetes and diabetic macular edema (DME) were each treated with a single intravitreal injection of aflibercept (2.0 mg, 50 µL) monthly for three consecutive months. Plasma galectin-1 and VEGF-A levels were measured just before an injection was administered, 1 week after the first injection, and 2 months after the last injection. Nineteen age- and sex-matched healthy participants served as controls.

RESULTS

Irrespective of the tested galectin-1 concentration, 24% of added galectin-1 was precipitated by aflibercept. Baseline plasma concentrations of galectin-1 were 22.0 and 23.0 ng/mL in the control and aflibercept-treated groups, respectively. Systemic galectin-1 levels increased to 27.0 and 24.0 ng/mL at 7 days and 4 weeks, respectively, after treatment. At week 8, plasma galectin-1 levels significantly increased to 36.0 ng/mL. This level persisted for 20 weeks. Systemic VEGF-A levels significantly reduced to below the minimum detectable dose in 16 DME patients at 7 days after treatment. This level persisted for 4 weeks. Plasma VEGF-A levels were reduced at weeks 8 (p = 0.099) and 20 (p = 0.023). Decreased plasma VEGF-A levels were observed in all patients after treatment.

CONCLUSION

We confirmed that physiological aflibercept levels precipitate galectin-1 in in vitro assays. Additionally, systemic upregulation of galectin-1 might be induced by intravitreal aflibercept, which may be relevant in the clinical outcomes of DR treatment.

Overweight, hyperglycemia and tobacco use are modifiable risk factors for onset of retinopathy 9 and 17years after the diagnosis of diabetes - A retrospective observational nation-wide cohort study

BACKGROUND

The aims of this study were to estimate the risk for diabetic retinopathy (DR) and to identify risk factors. We investigated a nationwide population-based cohort with diabetes diagnosed at age 15-34years.

PATIENTS AND METHODS

Of 794 patients registered 1987-1988 in the Diabetes Incidence Study in Sweden (DISS) 444 (56%) patients with retinal photos available for classification of retinopathy participated in a follow-up study 15-19 (median 17) years after diagnosis. Mean age was 42.3±5.7years, BMI 26.1±4.1kg/m², 62% were male and 91% had type 1 diabetes. A sub-study was performed in 367 patients with retinal photos from both the 9 and 17year follow up and the risk for development of retinopathy between 9 and 17years of follow up was calculated.

RESULTS

After median 17years 324/444 (73%, 67% of T1D and 71% of T2D), had developed any DR but only 5.4% proliferative DR. Male sex increased the risk of developing retinopathy (OR 1.9, 95% CI 1.2-2.9). In the sub-study obesity (OR 1.2, 95% CI 1.04-1.4), hyperglycemia (OR 2.5, 95% CI 1.6-3.8) and tobacco use (OR 2.9, 95% CI 1.1-7.3) predicted onset of retinopathy between 9 and 17years after diagnosis of diabetes.

CONCLUSION

The number of patients with severe retinopathy after 17years of diabetes disease was small. The risk of developing retinopathy with onset between 9 and 17years after diagnosis of diabetes was strongly associated to modifiable risk factors such as glycemic control, obesity and tobacco use.

Clinical characteristics and risk factors for retinal diabetic neurodegeneration in type 2 diabetes

AIMS

To identify clinical characteristics and risk factors of retinal neurodegeneration represented by macular ganglion cell/inner plexiform layer (mGCIPL) thinning in patients with long-standing type 2 diabetes mellitus (T2DM).

METHODS

Patients who had T2DM for >15 years were prospectively recruited from September 2014 to July 2015. Clinical data and samples were collected according to the Common Data Element and Standards of Procedure developed by the Korean Diabetes Association research council. Baseline characteristics included age, gender, family history, medical record of comorbidity, and microvascular complications. All patients underwent optical coherence tomography with automatic segmentation of the mGCIPL in six parafoveal regions. Multivariable regression analysis identified factors associated with mGCIPL thinning.

RESULTS

Of 220 registered patients, 162 were included after ophthalmologic examination. The mean (SD) age was 65.0 (9.3) years, the mean duration of T2DM was 20.5 (4.0) years; mGCIPL thickness was 76.2 (8.5) µm. Hypertension, diabetic retinopathy, statin medication, estimated glomerular filtration rate, conduction velocity of the posterior tibial, peroneal, and sural nerves, and cardiac autonomic neuropathy (CAN) score were significantly correlated with mGCIPL thickness. Multivariate regression analysis showed that the CAN score (coefficient = -1.78, p = 0.001) and sural nerve velocity (coefficient = 0.458, p = 0.035) yielded a significant high regression correlation with mGCIPL thickness (overall R ² = 0.46).

CONCLUSIONS

This study demonstrated that various clinical features were associated with retinal neurodegeneration in T2DM. In particular, peripheral nerve conduction and autonomic nerve function were confirmed to be strong risk factors for mGCIPL thinning in patients with T2DM.

Features of Long-Standing Korean Type 2 Diabetes Mellitus Patients with Diabetic Retinopathy: A Study Based on Standardized Clinical Data

BACKGROUND

This is part of a prospective study carried out as a national project to secure standardized public resources for type 2 diabetes mellitus (T2DM) patients in Korea. We compared various characteristics of long-standing T2DM patients with diabetic retinopathy (DR) and macular edema (ME).

METHODS

From September 2014 to July 2015, T2DM patients with disease duration of at least 15 years were recruited at a single university hospital. Clinical data and samples were collected according to the common data elements and standards of procedure developed by the Korean Diabetes Association Research Council. Each participant was assessed by ophthalmologists for DR and ME.

RESULTS

Among 220 registered patients, 183 completed the ophthalmologic assessment. DR was associated with longer disease duration (odds ratio [OR], 1.071; 95% confidence interval [CI], 1.001 to 1.147 for non-proliferative diabetic retinopathy [NPDR]) (OR, 1.142; 95% CI, 1.051 to 1.242 for proliferative diabetic retinopathy [PDR]) and the use of long-acting insulin (OR, 4.559; 95% CI, 1.672 to 12.427 for NPDR) (OR, 4.783; 95% CI, 1.581 to 14.474 for PDR), but a lower prevalence of a family history of cancer (OR, 0.310; 95% CI, 0.119 to 0.809 for NPDR) (OR, 0.206; 95% CI, 0.063 to 0.673 for PDR). ME was associated with higher glycosylated hemoglobin levels (OR, 1.380; 95% CI, 1.032 to 1.845) and the use of rapid-acting insulin (OR, 5.211; 95% CI, 1.445 to 18.794).

CONCLUSION

Various clinical features were associated with DR and ME. Additional epidemiological and biorepository-based studies using this cohort are being conducted to deepen our understanding of diabetic complications in Korea.

DIABETES ALTERS THE MAGNITUDE OF VITREOMACULAR ADHESION

PURPOSE

To quantify the changes in vitreomacular interactions that occur with aging in diabetic eyes in comparison with age-matched control eyes.

METHODS

Spectral-domain optical coherence tomography (Spectralis; Heidelberg Engineering) foveal scans of diabetic patients, without evidence of cystoid macular edema, were included. Twenty-five raster foveal scans were performed on every subject. Area of vitreomacular adhesion was delineated using the Spectralis drawing tool and calculated in square millimeter. Data collected included gender, race, best-corrected visual acuity, and posterior vitreous detachment status. Subjects were divided into age groups according to decade of life.

RESULTS

Spectral-domain optical coherence tomography scans from 141 diabetic patients were analyzed. Area of vitreomacular adhesion (mm) showed a hyperbolic decline in diabetic patients (35.5 ± 0, 35.0 ± 3, 34.0 ± 3, 33.9 ± 5, 33.7 ± 6, 29.0 ± 11, 23 ± 15, 13 ± 15). With aging, incidence of posterior vitreous detachment increased and incidence of complete attachment decreased.

CONCLUSION

Diabetes affects the magnitude of attachment of the vitreous gel to the macula that results in stronger and longer lasting attachment of the gel throughout life. Gender differences were not noticed in diabetic patients, suggesting that vitreomacular adhesion remains robust in both genders in diabetes despite aging.

Semi-automated quantification of hard exudates in colour fundus photographs diagnosed with diabetic retinopathy

Background

Hard exudates (HEs) are the classical sign of diabetic retinopathy (DR) which is one of the leading causes of blindness, especially in developing countries. Accordingly, disease screening involves examining HEs qualitatively using fundus camera. However, for monitoring the treatment response, quantification of HEs becomes crucial and hence clinicians now seek to measure the area of HEs in the digital colour fundus (CF) photographs. Against this backdrop, we proposed an algorithm to quantify HEs using CF images and compare with previously reported technique using ImageJ.

Methods

CF photographs of 30 eyes (20 patients) with diabetic macular edema were obtained. A robust semi-automated algorithm was developed to quantify area covered by HEs. In particular, the proposed algorithm, a two pronged methodology, involved performing top-hat filtering, second order statistical filtering, and thresholding of the colour fundus images. Subsequently, two masked observers performed HEs measurements using previously reported ImageJ-based protocol and compared with those obtained through proposed method. Intra and inter-observer grading was performed for determining percentage area of HEs identified by the individual algorithm.

Results

Of the 30 subjects, 21 were males and 9 were females with a mean age of the 50.25 ± 7.80 years (range 33–66 years). The correlation between the two measurements of semi-automated and ImageJ were 0.99 and 0.99 respectively. Previously reported method detected only 0–30% of the HEs area in 9 images, 30–60% in 12 images and 60–90% in remaining images, and more than 90% in none. In contrast, proposed method, detected 60–90% of the HEs area in 13 images and 90–100% in remaining 17 images.

Conclusion

Proposed method semi-automated algorithm achieved acceptable accuracy, qualitatively and quantitatively, on a heterogeneous dataset. Further, quantitative analysis performed based on intra- and inter-observer grading showed that proposed methodology detects HEs more accurately than previously reported ImageJ-based technique. In particular, we proposed algorithm detect faint HEs also as opposed to the earlier method.

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.

TLR7 deficiency contributes to attenuated diabetic retinopathy via inhibition of inflammatory response

Diabetic retinopathy (DR) is a major microvascular complication of diabetes, resulting in neuronal dysfunction, retinal vascular leakage, and apoptosis within the retina. Innate immunity plays an important role in the pathogenesis of type 2 diabetes (T2D) and related complications. The toll-like receptors (TLRs), central to innate immunity, are essential participants in the progression and pathogenesis of the disease and its complications. In the study, streptozotocin (STZ) was combined with whole-body hypoxia for quicker induction of early-stage diabetic retinopathy (DR) in the wild type (WT) and TLR7-knockout (KO) C57BL/6 mice. The effects of TLR7 were also investigated in fructose-treated retinal pigment epithelial (RPE) cells. In the retinas of WT/DR mice, abnormal a-wave and b-wave activity, hyperfluorescence, and reduced retinal thickness were observed. DR development was associated with enhanced TLR7 expression, whose deletion dramatically reduced VEGF expression levels. And the secretion of pro-inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-18 and IL-12, was highly reduced by TLR7-deficiency in DR mice. Consistently, WT/DR mice exhibited higher phosphorylation of IκB kinase α (IKKα), inhibitor of NF-κB α (IκBα) and nuclear factor κB (NF-κB), which were found to be down-regulated in KO/DR mice. Similarly, DR-induced mitogen-activated protein kinases (MAPKs) activation was blocked by TLR7-knockout. In vitro, fructose incubation-triggered inflammation was reversed by TLR7 knockdown, accompanied with inactivated NF-κB and MAPKs pathways. And reduced reactive oxygen species (ROS) generation was observed in TLR7-knockdown cells with fructose treatment. Together, inhibiting TLR7 suppressed diabetic retinopathy by reducing inflammation and suggested a potential application in clinics.

Peripapillary RNFL Thickness Changes after Panretinal Photocoagulation

PURPOSE

To evaluate changes in peripapillary retinal nerve fiber layer (RNFL) thickness as determined by spectral domain optical coherence tomography (SD-OCT) after panretinal photocoagulation (PRP) for proliferative diabetic retinopathy (PDR).

METHODS

Forty-two eyes of 42 diabetic patients who were scheduled for PRP were enrolled in this interventional case series. Peripapillary RNFL thickness was measured using SD-OCT (OCT 1000; Topcon Co., Tokyo, Japan) at baseline and 1, 3, and 6 months after PRP.

RESULTS

Mean global RNFL thickness was increased significantly by 3 μm (p = 0.04) 1 month after PRP and was then decreased marginally significantly by 2.4 μm at 6 months (p = 0.054) as compared to baseline values. After 1 month, RNFL thickness was increased in all quadrants, but only changes in the temporal quadrant were significant (p = 0.009). At 6 months, progressive RNFL thinning occurred in all quadrants; however, only changes in the superior quadrant were significant (p = 0.041). Visual acuity was improved by an average of 0.02 logMAR after 6 months, but this change was not statistically significant.

CONCLUSIONS

Shortly after PRP, RNFL thickness (as determined by SD-OCT) increases, but a decrease in RNFL thickness occurs at 6 months post-PRP. RNFL thickness changes based on OCT should be interpreted with caution in diabetic eyes undergoing PRP.

The Status of Maculopathy in Diabetes and Prediabetes Patients in a Population-Based Study Detected by Optical Coherence Tomography: The 2011 Health Examination Survey in Beijing

Objective

The aim of the study was to investigate the prevalence and the risk factors of maculopathy detected by optical coherence tomography (OCT) in a Chinese population with diabetes or prediabetes. Methods. 8,155 people were randomly selected to participate in the 2011 annual Health Examination Survey in Beijing. A 75 g oral glucose tolerance test (OGTT) was tested in 3760 subjects with fasting plasma glucose (FPG) ≥ 5.6 mmol/L. Of 3,760 subjects, 583 were also randomly selected to take OCT.

Results

In this study population, 21 (3.95%) patients had maculopathy. Eight patients had diabetes macular edema (DME) and the prevalence was 6.72% in diabetes patients and 1.51% in all subjects. Eleven patients had age-related macular degeneration (AMD) and the prevalence was 3.36% in diabetes patients and 2.07% in all subjects. Logistic regression model confirmed that elevated HbA1c (p < 0.001) and systolic pressure (p < 0.05) made significant contributions to DME. Stepwise regression analysis revealed that HbA1c and blood creatinine were significantly independent influence factors for central subfield thickness (CST) (p = 0.01, p < 0.001).

Conclusions

High prevalence of maculopathy was found in patients with diabetes in a Chinese population. Maculopathy poses a significant public health problem in China with rapid rising trend of diabetes.

1-Acetyl-5-phenyl-1H-pyrrol-3-ylacetate: An aldose reductase inhibitor for the treatment of diabetic nephropathy

Diabetic nephropathy (DN) is the most common and serious complication in diabetes mellitus, but the efficacy of available strategies for preventing this disorder remains poor. The aim of this study was to investigate the possible beneficial effects of 1-acetyl-5-phenyl-1H-pyrrol-3-ylacetate (APPA), an aldose reductase inhibitor, on DN. In the present study, a model of rat glomerular mesangial cells (HBZY-1) damaged by high glucose was used to confirm the protective effects of APPA in vitro. Then, a rat model of streptozotocin-induced diabetes was used to assess the effects of APPA in vivo. APPA increased viability and reduced apoptosis in HBZY-1 cells. In vivo, APPA improved the signs of DN as determined by measurements of blood glucose, urinary microalbumin, serum total antioxidant capacity, serum catalase activity, serum glutathione levels, and serum total superoxide dismutase activity. Hematoxylin and eosin staining of kidney tissue confirmed the protective effect. Moreover, APPA reduced the levels of transforming growth factor-β1, collagen IV, and laminin in HBZY-1cells incubated in high glucose, and in serum in DN rats. In summary, APPA can effectively prevent apoptosis and the symptoms of streptozotocin-induced diabetes by inhibiting the polyol pathway in rats. This suggests that APPA could be a potential drug in treating DN.

Association of Bone Metabolic Markers With Diabetic Retinopathy and Diabetic Macular Edema in Elderly Chinese Individuals With Type 2 Diabetes Mellitus

BACKGROUND

Diabetic retinopathy (DR) is a common and specific microvascular complication of diabetes. The association of bone metabolic markers with the risk of DR and diabetic macular edema (DME) is unclear.

MATERIALS AND METHODS

We investigated the association between bone turnover markers commonly examined in a clinical setting and DR and DME risk in elderly Chinese patients with type 2 diabetes mellitus (T2DM). A total of 408 patients aged 55-70 years with T2DM were included. We first performed univariable logistic regression followed by multivariable logistic regression that included variables selected using purposeful selection.

RESULTS

Fasting blood glucose (P = 0.007) and duration of diabetes (P < 0.0001) were significantly associated with DME in multivariable logistic regression; however, the association of beta C-terminal telopeptide of collagen type I (β-CTx) with DME risk was not statistically significant (P = 0.053). Sex-stratified analysis showed that β-CTx was significantly associated with DME only in female subjects (P = 0.011).

CONCLUSIONS

β-CTx had no significant association with DR. It was significantly associated with DME in female patients with T2DM, but not in male patients with T2DM. More prospective studies with larger sample sizes are warranted to validate our findings.

Connexin channel and its role in diabetic retinopathy

Diabetic retinopathy is the leading cause of blindness in the working age population. Unfortunately, there is no cure for this devastating ocular complication. The early stage of diabetic retinopathy is characterized by the loss of various cell types in the retina, namely endothelial cells and pericytes. As the disease progresses, vascular leakage, a clinical hallmark of diabetic retinopathy, becomes evident and may eventually lead to diabetic macular edema, the most common cause of vision loss in diabetic retinopathy. Substantial evidence indicates that the disruption of connexin-mediated cellular communication plays a critical role in the pathogenesis of diabetic retinopathy. Yet, it is unclear how altered communication via connexin channel mediated cell-to-cell and cell-to-extracellular microenvironment is linked to the development of diabetic retinopathy. Recent observations suggest the possibility that connexin hemichannels may play a role in the pathogenesis of diabetic retinopathy by allowing communication between cells and the microenvironment. Interestingly, recent studies suggest that connexin channels may be involved in regulating retinal vascular permeability. These cellular events are coordinated at least in part via connexin-mediated intercellular communication and the maintenance of retinal vascular homeostasis. This review highlights the effect of high glucose and diabetic condition on connexin channels and their impact on the development of diabetic retinopathy.

Dexamethasone implant with fixed or individualized regimen in the treatment of diabetic macular oedema: six-month outcomes of the UDBASA study

PURPOSE

To evaluate a pro re nata administration of Ozurdex^® implant versus a single administration for treating diabetic macular oedema (DME).

METHODS

This exploratory study is designed as a comparative, multicentre, randomized study with a follow-up of 6 months. Patients with DME were assigned to treatment at baseline either with a single Ozurdex^® implant during the entire six-month follow-up (fixed group) or Ozurdex^® implant followed by retreatment on an individualized basis (PRN group). Patients were scheduled for monthly evaluation based on assessment of best-corrected visual acuity (BCVA) and optical coherence tomography.

RESULTS

Twenty eyes were enrolled to the PRN group, and 22 were included in the fixed group. Following an equally steady, initial gain up to month 1, and maintenance up to month 3, vision started to decline in the fixed regimen group. At 6 months, a difference of 0.11 logMAR in BCVA was observed in favour of the PRN group. Compared to baseline, a significant reduction in retinal thickness was achieved up to month 2, when the fixed regimen group had begun to revert to pretreatment level. At 4 and 5 months, the difference in thickness between the two groups was statistically significant (p < 0.05). Mean number of treatments was 1.6 in the PRN group. Both fixed and PRN administration of Ozurdex showed a good safety profile.

CONCLUSION

A personalized treatment with monthly monitoring and retreatment as needed is effective in maintaining functional and anatomical benefits of Ozurdex^® .

Validity, Usefulness and Cost of RETeval System for Diabetic Retinopathy Screening

Purpose

We studied the validity, usefulness, and relative cost to detect diabetic retinopathy (DR) and sight-threatening DR (STDR) by using a hand-held electrophysiologic tool compared to digital fundus photography.

Method

Patients with diabetes attending the screening unit of King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia were evaluated by “RETeval”, Amsler grid, and digital dilated fundus photography. Fundus images were evaluated by a retina specialist to determine grade of DR. The sensitivity and specificity of STDR and DR screening compared to photography were calculated, as well as “RETeval” combined with Amsler grid testing. The area under the curve (AUC) of “RETeval” screening outcome was calculated.

Result

We analyzed data of 400 diabetic patients. The prevalence of DR of any grade was 48.8% (95% confidence interval [CI], 43.9–53.7) while the prevalence of STDR was 27% (95% CI, 22.6–31.4). The outcome of RETeval test was “fail” (based on 20 μV or more amplitude of electrophysiologic spikes) in 351 (87.8%; 95% CI, 84.5–91.0) eyes. The sensitivity of the device was 95.4% and the specificity was 17.5%. Thus, the sensitivity of sequential testing with RETeval and Amsler grid test was 30.1% and the specificity was 80.1%. The AUCs for STDR and DR in general were 76.6% and 50.6%, respectively.

Conclusions

“RETeval” is a rapid screening device with excellent sensitivity for detecting STDR. It has potential as a first level screening tool to detect patients who require further evaluation.

Translational Relevance

Retinal function, such as electrophysiology, can be used as a new concept for screening for DR.

Therapeutic Options in Refractory Diabetic Macular Oedema

Diabetic macular oedema (DMO) results from alterations of several biochemical pathways in diabetic eyes. Centre-involving DMO is an important cause of visual loss in diabetes. Anti-vascular endothelial growth factor agents are now the mainstay of centre-involving DMO treatment. Oedema that does not achieve optimal response to these agents occurs in a sizeable proportion of eyes and is called refractory or persistent DMO. Management of refractory DMO is challenging. In this paper, the pathophysiology of DMO, and the definitions used in various studies are summarised. Therapeutic options for refractory DMO management including corticosteroids, laser, combination therapies, and surgery are explored. Novel agents on the horizon for DMO control that are being investigated at present are discussed as well. A literature review was performed and a summary of the research studies for each of the agents is provided in order to guide the reader regarding the existing evidence for their application in DMO. Importance of early recognition of disease and prompt treatment to achieve best visual outcome is discussed. Utility of optical coherence tomography to guide disease diagnosis and monitoring is highlighted. An algorithmic approach for DMO management is described. Finally, the impact that personalized medicine and genetics might have on DMO management is assessed.

Altered eigenvector centrality is related to local resting-state network functional connectivity in patients with longstanding type 1 diabetes mellitus

INTRODUCTION

Longstanding type 1 diabetes (T1DM) is associated with microangiopathy and poorer cognition. In the brain, T1DM is related to increased functional resting-state network (RSN) connectivity in patients without, which was decreased in patients with clinically evident microangiopathy. Subcortical structure seems affected in both patient groups. How these localized alterations affect the hierarchy of the functional network in T1DM is unknown. Eigenvector centrality mapping (ECM) and degree centrality are graph theoretical methods that allow determining the relative importance (ECM) and connectedness (degree centrality) of regions within the whole-brain network hierarchy.

METHODS

Therefore, ECM and degree centrality of resting-state functional MRI-scans were compared between 51 patients with, 53 patients without proliferative retinopathy, and 49 controls, and associated with RSN connectivity, subcortical gray matter volume, and cognition.

RESULTS

In all patients versus controls, ECM and degree centrality were lower in the bilateral thalamus and the dorsal striatum, with lowest values in patients without proliferative retinopathy (P_FWE  < 0.05). Increased ECM in this group versus patients with proliferative retinopathy was seen in the bilateral lateral occipital cortex, and in the right cuneus and occipital fusiform gyrus versus controls (P_FWE  < 0.05). In all patients, ECM and degree centrality were related to altered visual, sensorimotor, and auditory and language RSN connectivity (P_FWE  < 0.05), but not to subcortical gray matter volume or cognition (P_FDR  > 0.05).

CONCLUSION

The findings suggested reorganization of the hierarchy of the cortical connectivity network in patients without proliferative retinopathy, which is lost with disease progression. Centrality seems sensitive to capture early T1DM-related functional connectivity alterations, but not disease progression. Hum Brain Mapp 38:3623-3636, 2017. © 2017 Wiley Periodicals, Inc.

New Drugs and New Posterior Delivery Methods in CME

PURPOSE

To discuss the characteristics, indications and adverse events (AEs) of sustained-release corticosteroid devices for the treatment of cystoid macular edema (CME).

RECENT FINDINGS

Ozurdex® is approved for the treatment of diabetic macular edema (DME), retinal vein occlusion related-CME and noninfectious posterior uveitis (NIPU). It releases dexamethasone over a maximum period of 6 months making repeated intravitreal injections necessary for recurrent CME. Iluvien® releases fluocinolone for up to 36 months and is effective for the treatment of chronic DME. Retisert® (Bausch & Lomb, Rochester, NY) also releases fluocinolone, and is approved for chronic NIPU. Both Iluvien® and Retisert® are non-biodegradable devices and are highly associated with cataract and glaucoma.

SUMMARY

Long-acting intraocular corticosteroid formulations offer a more predictable drug-release profile and reduced dosing frequency in comparison to conventional formulations of the same compounds but the risk-benefit ratio must be taken into consideration previous to the implantation of those devices.

Plasma level of miR-93 is associated with higher risk to develop type 2 diabetic retinopathy

PURPOSE

MicroRNA-93 (miR-93) usually acts as a promoter of tumor progression in several human carcinomas. It has been found distinctly high in eyes with proliferative diabetic retinopathy (DR). The present study aims to investigate the role of plasma miR-93 in the progression of type 2 diabetic retinopathy (T2DR).

METHODS

Our study subjects were made up of 140 type 2 diabetes mellitus (T2DM) patients who were assigned into DR (DR patients, n = 75), NDR (non-DR patients, n = 65), and control (healthy individuals, n = 127) groups. Levels of fasting blood glucose (FBG), fasting plasma glucose (FPG), triglyceride (TG), glycosylated hemoglobin (HbA1c), total cholesterol (TC), blood urea nitrogen (BUN), creatinine (Cr), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and fasting insulin (FIsn) were detected by automatic biochemical analyzer. Enzyme-linked immunosorbent assay (ELISA) was performed for the levels of interleukin (IL)-1, IL-6, tumor necrosis factor (TNF)-α and vascular endothelial growth factor (VEGF), qRT-PCR for the miR-93 expression in plasma, and mRNA expressions of IL-1, IL-6, TNF-α and VEGF; receiver operating characteristic (ROC) curve for the diagnostic performance of miR-93 to T2DR, Pearson correlation analysis for correlation analysis between miR-93 and other indexes detected before and multivariate logistic regression analyses for the risk factors for T2DR.

RESULTS

The DR and NDR groups exhibited elevated course of disease, and decreased levels of FBG, FPG, TG, HbA1c, TC, BUN, Cr, HDL-C, FIsn, IL-1, IL-6, TNF-α and VEGF but declined LDL-C level as compared to the control group. The course of disease was longer and the levels of FBG, FPG, HbA1c, IL1, IL6 and VEGF were higher in the DR group than those in the NDR group (all P < 0.05). The miR-93 expression and RNA expressions of IL-1, IL-6, TNF-α and VEGF were higher in the DR group than those in the NDR group (P < 0.05). The best cutoff for miR-93 to assess T2DR was 1.31, with a Youden index of 0.63, sensitivity of 73.33%, specificity of 89.24%, and area under the curve (AUC) of 0.866. Pearson correlation analysis indicated that miR-93 expression was positively associated with course of disease, the levels of FPG, HbA1c, TNF-α and VEGF. T2DM patients with longer disease course, higher levels of FBG, HbA1c, VEGF and miR-93 expression were risk factors for developing DR.

CONCLUSION

Our study demonstrates that plasma miR-93 is associated with the progression of T2DR and it can sever as a diagnostic marker for T2DR.

Predictive factors of better outcomes by monotherapy of an antivascular endothelial growth factor drug, ranibizumab, for diabetic macular edema in clinical practice

Intravitreal ranibizumab (IVR) has been approved for treating diabetic macular edema (DME), and is used in daily clinical practice. However, the treatment efficacies of IVR monotherapy in real-world clinical settings are not well known.The medical records of 56 eyes from 38 patients who received their first IVR for DME between April 2014 and March 2015, and were retreated with IVR monotherapy as needed with no rescue treatment, such as laser photocoagulation, were retrospectively reviewed. The clinical course, best-corrected visual acuity (BCVA), and fundus findings at baseline, before the initial IVR injection, and at 12 months, were evaluated.Twenty-five eyes from 25 patients (16 men; mean age 68.7 ± 9.8 years) who received IVR in the first eye, or unilaterally, without any other treatments during follow-up were included. After 12 months, mean central retinal thickness (CRT), which includes edema, was reduced (P = .003), although mean BCVA remained unchanged. There was a negative correlation between individual changes in BCVA (r = -0.57; P = .003) and CRT (r = -0.60; P = .002) at 12 months compared with baseline values. BCVA changes were greater in individuals with a history of pan-retinal photocoagulation at baseline (P = .026). After adjusting for age and sex, CRT improvement >100 μm at 12 months was associated with a greater CRT at baseline (OR 0.87 per 10 μm [95% CI 0.72-0.97]; P = .018) according to logistic regression analyses; however, better BCVA and CRT at 12 months were associated with a better BCVA (r = 0.77; P < .001) and lower CRT (r = 0.41; P = .039) at baseline, respectively, according to linear regression analyses.IVR monotherapy suppressed DME, and the effects varied according to baseline conditions. Eyes that had poorer BCVA or greater CRT, or a history of pan-retinal photocoagulation at baseline, demonstrated greater improvement with IVR monotherapy. In contrast, to achieve better outcome values, DME eyes should be treated before the BCVA and CRT deteriorate. These findings advance our understanding of the optimal use of IVR for DME in daily clinical practice, although further study is warranted.

Setting Priorities for Diabetic Retinopathy Clinical Research and Identifying Evidence Gaps

PURPOSE

Prioritizing comparative effectiveness research may contribute to obtaining answers that clinicians perceive they need and may minimize research that could be considered wasteful. Our objective was to identify evidence gaps and set priorities for new systematic reviews and randomized controlled trials for managing diabetic retinopathy (DR), including diabetic macular edema (DME).

DESIGN

Cross-sectional study.

PARTICIPANTS

Diabetic Retinopathy Clinical Research Network (DRCR.net) investigators.

METHODS

We provided recommendations from the American Academy of Ophthalmology's 2012 Preferred Practice Patterns for Diabetic Retinopathy as 91 answerable clinical research questions about intervention effectiveness to 410 DRCR.net investigators to rate each question's importance from 0 (not important) to 10 (very important) using a 2-round Delphi survey and to suggest additional questions. We considered questions as high priority if at least 75% of respondents to both rounds assigned an importance rating of 5 or more in round 2. We also extracted outcome measures relevant to DR and asked respondents to identify those that must be measured in all studies. We mapped Cochrane reviews published up to March 2016 to high-priority clinical research questions.

MAIN OUTCOME MEASURE

Ranking of importance of each clinical question.

RESULTS

Thirty-two individuals completed rounds 1 and 2 and suggested 15 questions. Among the final list of 106 clinical research questions, 22 questions met our definition of high priority: 9 of 22 concerned the effectiveness of anti-VEGF therapy, and 13 of 22 focused on how often patients should be followed up (re-examination) and treatment effectiveness in patients with specific characteristics (e.g., DME). Outcomes that 75% or more of respondents marked as "must be measured in all studies" included visual acuity and visual loss, death of participants, and intraocular pressure. Only 1 prioritized question was associated with conclusive evidence from a Cochrane systematic review.

CONCLUSIONS

A limited response rate among DRCR.net members identified 22 comparative effectiveness research questions as high priority for the management of DR, including DME, but few were associated with Cochrane reviews. These results support the need of systematic reviews and randomized controlled trials to address evidence gaps.

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.

Diabetic macular oedema

Diabetic macular oedema, characterised by exudative fluid accumulation in the macula, is the most common form of sight-threatening retinopathy in people with diabetes. It affects one in 15 people with diabetes resulting in more than 20 million cases worldwide. Few epidemiological studies have been done to specifically investigate risk factors for diabetic macular oedema, although poor glycaemic and blood pressure control are associated with the presence and development of the disorder. The pathophysiological processes begin with chronic hyperglycaemia, and interplay between vascular endothelial growth factor (VEGF) and inflammatory mediators. Non-invasive imaging using optical coherence tomography has allowed clinicians to detect mild levels of diabetic macular oedema in order to monitor progress and guide treatment. Although focal or grid laser photocoagulation was the traditional mode of treatment, intraocular pharmacotherapy with anti-VEGF agents is now the standard of care. However, these therapies are expensive and resource intensive. Emerging therapeutic strategies include improving efficacy and duration of VEGF suppression, targeting alternative pathways such as inflammation, the kallikrein-kinin system, the angiopoietin-Tie2 system, and neurodegeneration, and using subthreshold and targeted laser therapy. Ongoing research should lead to improvements in screening, diagnosis, and management of diabetic macular oedema.

Prevalence of referable, sight-threatening retinopathy in type 1 diabetes and its relationship to diabetes duration and systemic risk factors

PurposeThe purpose of the study was to provide contemporary estimates for diabetic retinopathy (DR) prevalence in a well-defined UK cohort of patients with type 1 diabetes (T1DM) and investigate potential risk factors for proliferative diabetic retinopathy (PDR) and diabetic maculopathy.Patients and MethodsFour hundred and sixty four T1DM patients in North Hampshire had T1DM duration, demographic and systemic risk factor data evaluated retrospectively alongside their DR status in 2010 using logistic regression analysis.ResultsOverall prevalence of any retinopathy, PDR, and maculopathy was 71.5%, 6.5%, and 10.8%, respectively. PDR and maculopathy prevalence were 0 and 0.7% for <10 years T1DM duration. PDR prevalence was 4%, 8%, and 16% for 10-19.9 years, 20-29.9, years and ≥30 years duration, respectively. Maculopathy prevalence was 15.6%, 18%, and 11% for 10-19.9 years, 20-29.9 years, and ≥30 years duration, respectively. In univariate analysis, PDR was associated with T1DM duration (odds ratio (OR) 1.07/year), age (OR 1.03/year), systolic blood pressure (OR 1.03/mmHg), and antihypertensive therapy (OR 10.63), while maculopathy was associated with duration (OR 1.03/year) and statin therapy (OR 2.83). In multivariate analysis, disease duration (OR 1.07/year) and antihypertensive therapy (OR 6.87) remained significantly associated with PDR, and maculopathy with statin therapy (OR 2.27).ConclusionThis study confirms T1DM duration is a strong risk factor for sight-threatening DR. Maculopathy and PDR prevalence within 10 years of T1DM diagnosis is very low. PDR prevalence at 10-20 years was 4% and then doubled for every 10-year interval thereafter up to 16% with ≥30 years duration. Antihypertensive therapy and statin therapy were strongly associated with PDR and maculopathy, respectively.

Cardiovascular involvement in patients with diabetic macular oedema treated with intravitreal ranibizumab in routine clinical practice

OBJECTIVE

To determine the cardiovascular events in naïve patients with diabetic macular oedema, before and after being treated with intravitreal ranibizumab.

MATERIAL AND METHODS

A retrospective and descriptive study was conducted on patients with diabetic macular oedema and foveal involvement, who started treatment with intravitreal ranibizumab in 2014 in the Hospital Universitario Nuestra Señora de Candelaria and the Hospital Universitario y Politécnico La Fe. During the follow-up until August 2015, a record was made of parameters, including the prevalence and incidence of stroke and myocardial infarction.

RESULTS

Among the 1,324 intravitreal ranibizumab injections administered in 2014, only 159 of them corresponded to treatment initiation in 99 patients, with more than half requiring treatment of both eyes. The study patients included 58.4% males, in the 6th decade of life (Mean=65.93±11.24 years), non-smokers (86.7%), type 2 diabetes (91.9%), hypertension (70.7%), and with dyslipidaemia (65.7%). Prior to treatment initiation, it was found that 6 patients (6.1%) suffered from an acute myocardial infarction, and 8 (8.1%) from stroke, and only one (1%) with post-stroke (P=.039).

CONCLUSION

In our experience it seems that the intravitreal ranibizumab in diabetic macular oedema could be a safe alternative in patients with a history of stroke and myocardial infarction.

Type 2 Diabetes Genetic Variants and Risk of Diabetic Retinopathy

PURPOSE

Genetic association studies to date have not identified any robust risk loci for diabetic retinopathy (DR). We hypothesized that individuals with more diabetes genetic risk alleles have a higher risk of developing DR.

DESIGN

Case-control genetic association study.

PARTICIPANTS

We evaluated the aggregate effects of multiple type 2 diabetes-associated genetic variants on the risk of DR among 1528 participants with diabetes from the Singapore Epidemiology of Eye Diseases Study, of whom 547 (35.8%) had DR.

METHODS

Participants underwent a comprehensive ocular examination, including dilated fundus photography. Retinal photographs were graded using the modified Airlie House classification system to assess the presence and severity of DR following a standardized protocol. We identified 76 previously discovered type 2 diabetes-associated single nucleotide polymorphisms (SNPs) and constructed multilocus genetic risk scores (GRSs) for each individual by summing the number of risk alleles for each SNP weighted by the respective effect estimates on DR. Two GRSs were generated: an overall GRS that included all 76 discovered type 2 diabetes-associated SNPs, and an Asian-specific GRS that included a subset of 55 SNPs previously found to be associated with type 2 diabetes in East and/or South Asian ancestry populations. Associations between the GRSs with DR were determined using logistic regression analyses. Discriminating ability of the GRSs was determined by the area under the receiver operating characteristic curve (AUC).

MAIN OUTCOME MEASURES

Odds ratios on DR.

RESULTS

Participants in the top tertile of the overall GRS were 2.56-fold more likely to have DR compared with participants in the lowest tertile. Participants in the top tertile of the Asian-specific GRS were 2.00-fold more likely to have DR compared with participants in the bottom tertile. Both GRSs were associated with higher DR severity levels. However, addition of the GRSs to traditional risk factors improved the AUC only modestly by 3% to 4%.

CONCLUSIONS

Type 2 diabetes-associated genetic loci were significantly associated with higher risks of DR, independent of traditional risk factors. Our findings may provide new insights to further our understanding of the genetic pathogenesis of DR.

Comorbidity and health care visit burden in working-age commercially insured patients with diabetic macular edema

PURPOSE

To examine the comorbidity profile and update estimates of health care resource utilization for commercially insured, working-age adults with diabetic macular edema (DME) relative to a matched comparison group of diabetic adults without DME. Additional comparisons were made in the subgroup of pseudophakic patients.

PATIENTS AND METHODS

A retrospective matched-cohort study of commercially insured diabetic adults aged 18-63 years was conducted using medical and outpatient pharmacy claims (July 1, 2008-June 30, 2013). Outcomes included diabetes-related and ocular comorbidities and health care resource utilization (any health care visit days, outpatient visit days, inpatient visit days, emergency room visits, eye care-related visit days, unique medications) in the 12-month post-index period.

RESULTS

All diabetes-related and ocular comorbidities were significantly more prevalent in DME cases versus non-DME controls (P<0.05). A significantly greater proportion of DME cases utilized eye care-related visits compared with non-DME controls (P<0.001). DME cases had almost twice the mean number of total health care visit days compared to non-DME controls (28.6 vs 16.9 days, P<0.001), with a minority of visit days being eye care-related (mean 5.1 vs 1.5 days, P<0.001). Similar trends were observed in pseudophakic cohorts.

CONCLUSION

This working-age DME population experienced a mean of 29 health care visit days per year. Eye care-related visit days were a minority of the overall visit burden (mean 5 days) emphasizing the trade-offs DME patients face between managing DME and their overall diabetic disease. Insights into the complex comorbidity profile and health care needs of diabetic patients with DME will better inform treatment decisions and help optimize disease management.

Systematic screening of Retinopathy in Diabetes (REaD project): an Italian implementation campaign

PURPOSE

To evaluate the use of telemedicine retinal screening in Italy and to identify potential elements of implementation of this system.

METHODS

Patients with either new-onset diabetes or no ophthalmologic visit over the previous 2 years and attending 33 referral diabetic centers between mid-April 2013 and mid December 2015 were screened. Two partially overlapping nonstereoscopic 45° digital color images were captured from each eye using a fully automated nonmydriatic digital fundus camera. Factors limiting the assessment of retinopathy were explored.

RESULTS

Out of 24,473 eligible individuals, 22,466 had complete data. Among them, good-quality images enabling appropriate evaluation of at least one eye were obtained from 19,712 patients (both eyes, n = 18,887). Although nonmydriatic retinographs were provided, 39% of patients were evaluated using mydriasis. The rate of low-quality images in each center was inversely associated with the number of patients assessed. This was more evident for screening in mydriasis: adjusted odds ratio (OR) 0.79 (95% confidence interval (CI) 0.76-0.82) (p<0.001) vs 0.96 (95% CI 0.94-0.97) (p<0.001). Finally, both the number of patients assessed and use of mydriasis were inversely related to the presence of diabetic retinopathy (DR): adjusted OR 0.93 (95% CI 0.92-0.93) (p<0.001) and 0.88 (95% CI 0.82-0.96) (p<0.001), respectively.

CONCLUSIONS

This program confirmed a role for teleophthalmology in the systematic screening of DR and provided important suggestions to improve the system deployed. A high level of training is required for operators to optimize imaging. The role of mydriasis should be evaluated further.