Moderate Diabetic Retinopathy Research Articles

Retinal neurovascular changes appear earlier in type 2 diabetic patients.

To investigate the early neurodegenerative changes of inner retina and choroid in type 1 and type 2 diabetic patients without retinopathy and with early-stage retinopathy. In this observational cross-sectional study, 90 right eyes of 90 naive type 1 and 2 diabetic patients without diabetic retinopathy (DR) and with mild to moderate nonproliferative DR (NPDR) were analyzed. Forty healthy eyes were included as controls. We used spectral-domain optical coherence tomography to evaluate the ganglion cell complex (GCC) thickness, the retinal nerve fiber layer (RNFL) thickness, the choroid thickness, and the central foveal thickness (CFT) of patients and controls. Average GCC thickness turned out to be thinner in type 2 diabetic patients with no DR and with NPDR compared to controls (p = 0.046 and p = 0.041, respectively). The RNFL thickness and CFT were similar among the studied groups and compared to controls (p = 0.78 and p = 0.104, respectively). Average choroid thicknesses (both in the subfoveal area and in a 1-mm radius circular area) were significantly thinner in type 2 diabetic patients with no DR and NPDR, compared to DMT1 groups and controls (both p<0.0001). The GCC and choroid thickness changes were not correlated in any of the investigational groups. Type 2 diabetic patients without retinopathy and with early-stage retinopathy have inferior thickness values of GCC and choroid compared to controls. Insulin resistance might be a possible adjunctive pathogenetic aspect of neurodegeneration.

Macular thickness in diabetic eyes without clinical macular edema

PurposeTo evaluate macular thickness of individuals with moderate diabetic retinopathy (DR) without macular edema (DME).MethodsRetinal thickness was calculated by automated segmentation of spectral domain‐optical coherence tomography scans of patients with moderate DR without DME and compared with an age‐matched population of non‐diabetic individuals. Mean values and multiple linear regression analysis were used to determine the relationship between retinal layers thickness and age, sex, diabetes type and concentration of glycosylated hemoglobin (HbA1c).ResultsA total of 66 eyes were studied, 34 eyes with moderate DR without DME or previous treatment and 32 eyes from non‐diabetic individuals. The mean retinal nerve fiber layer (RNFL) thickness in the superior parafoveal area of patients with DR was 29.88 μm vs. 23.18 μm in the non‐diabetic group (p = 0.01). The mean inner nuclear layer thickness in the central fovea area in the DR group was 28.26 μm vs. 22.87 μm in the non‐diabetic control group (p = 0.01). There was a significant linear correlation (R = 0.353, p = 0.04) between HbA1c and the inner nuclear layer thickness in the superior parafoveal area.ConclusionsAccording to our findings, DR patients showed an increase of macular thickness compared with the non‐diabetic control group in the superior parafoveal and central foveal area. Increased HbA1c levels may play a role in the increased macular thickness.

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

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). 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. 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). 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 RETINOPATHY

Objectives: The purpose of this study was to evaluate the prevalence andcharacteristics of diabetic retinopathy (DR) in patients attending the free eye camps for cataractsurgery held in southern Punjab, Pakistan. Study Design: It was a cross sectional study. Setting:Free eye camps organized in different regions of the Southern Punjab, Pakistan. Period: July2004 to June 2015. Material and methods: These community-based eye camps were held bythe Department of Ophthalmology in collaboration of department of Pathology, B.V. Hospital,Bahawalpur, Pakistan. Participants were interviewed and examined by the ophthalmologists todetermine their demographic characteristics, presence &amp; duration of medical conditions andthe regularity of their visits to eye care providers. All patients screened to have diabetes mellitus(DM) by pathologists underwent an eye examination through dilated pupils by using direct/indirect ophthalmoscope and slit-lamp bio-microscope to check for any signs of DR. Mainoutcome measure was the presence of diabetic retinopathy and its complications, which wasclassified as mild, moderate, severe NPDR, and proliferative diabetic retinopathy (PDR) basedon the clinical examination. Results: Of the 7989 screened patients, 759 (9.5%) had type-II DM.Of them, 638 patients (84%) underwent eye examination. Mean age of the diabetics was 45.75 ±8.17 years. Diabetic retinopathy was prevalent in 93 (15%) patients followed by non-proliferativeretinopathy was found in 87 (93.5%) patients and proliferative retinopathy was found only in 6(6.5%) patients. More male 52 (20.39%) were effected of DR as compare to female 41 (10.7%).Highly significant association of DR with duration of DM was seen. (P: 0.001). Conclusion: Itis concluded in this study that DR is commonly prevalent in Southern Punjab and the mostcommon type of DR is non-proliferative retinopathy. DR frequently prevalent in male diabeticsas compare to female diabetics and significant association of duration of DM with DR wasfound.

English

Objectives: The purpose of this study was to evaluate the prevalence and characteristics of diabetic retinopathy (DR) in patients attending the free eye camps for cataract surgery held in southern Punjab, Pakistan. Study Design: It was a cross sectional study. Setting: Free eye camps organized in different regions of the Southern Punjab, Pakistan. Period: July 2004 to June 2015. Material and methods: These community-based eye camps were held by the Department of Ophthalmology in collaboration of department of Pathology, B.V. Hospital, Bahawalpur, Pakistan. Participants were interviewed and examined by the ophthalmologists to determine their demographic characteristics, presence & duration of medical conditions and the regularity of their visits to eye care providers. All patients screened to have diabetes mellitus (DM) by pathologists underwent an eye examination through dilated pupils by using direct/ indirect ophthalmoscope and slit-lamp bio-microscope to check for any signs of DR. Main outcome measure was the presence of diabetic retinopathy and its complications, which was classified as mild, moderate, severe NPDR, and proliferative diabetic retinopathy (PDR) based on the clinical examination. Results: Of the 7989 screened patients, 759 (9.5%) had type-II DM. Of them, 638 patients (84%) underwent eye examination. Mean age of the diabetics was 45.75 ± 8.17 years. Diabetic retinopathy was prevalent in 93 (15%) patients followed by non-proliferative retinopathy was found in 87 (93.5%) patients and proliferative retinopathy was found only in 6 (6.5%) patients. More male 52 (20.39%) were effected of DR as compare to female 41 (10.7%). Highly significant association of DR with duration of DM was seen. (P: 0.001) . Conclusion: It is concluded in this study that DR is commonly prevalent in Southern Punjab and the most common type of DR is non-proliferative retinopathy. DR frequently prevalent in male diabetics as compare to female diabetics and significant association of duration of DM with DR was found.

Glucose variability and inner retinal sensory neuropathy in persons with type 1 diabetes mellitus.

PurposeTo quantify early neuroretinal alterations in patients with type 1 diabetes mellitus (T1DM) and to assess whether glycemic variability contributes to alterations in neuroretinal structure or function.MethodsThirty patients with T1DM and 51 controls underwent comprehensive ophthalmic examination and assessment of retinal function or structure with frequency doubling perimetry (FDP), contrast sensitivity, dark adaptation, fundus photography, and optical coherence tomography (OCT). Diabetic participants wore a subcutaneous continuous glucose monitor for 5 days, from which makers of glycemic variability including the low blood glucose index (LGBI) and area under the curve (AUC) for hypoglycemia were derived.ResultsSixteen patients had no diabetic retinopathy (DR), and 14 had mild or moderate DR. Log contrast sensitivity for the DM group was significantly reduced (mean±SD=1.63±0.06) compared with controls (1.77±0.13, P<0.001). OCT analysis revealed that the inner temporal inner nuclear layer (INL) was thinner in patients with T1DM (34.9±2.8 μm) compared with controls (36.5±2.9 μm) (P=0.023), although this effect lost statistical significance after application of the Bonferroni correction for multiple comparisons. Both markers of glycemic variability, the AUC for hypoglycemia (R=-0.458, P=0.006) and LGBI (R=-0.473, P=0.004), were negatively correlated with inner temporal INL thickness.ConclusionsPatients with T1DM and no to moderate DR exhibit alterations in inner retinal structure and function. Increased glycemic variability correlates with retinal thinning on OCT imaging, suggesting that fluctuations in blood glucose may contribute to neurodegeneration.

Retinal ganglion cell neuronal damage in diabetes and diabetic retinopathy.

To examine the association of diabetes and diabetic retinopathy (DR) with retinal ganglion cell (RGC) loss. Observational case-control study. Type 2 diabetes cases and age-gender matched controls without diabetes. Spectral-domain optical coherence tomography (OCT) parameters of RGCs were calculated after automated segmentation of macular scans. DR severity was graded on fundus photographs using the modified Airlie House Classification system. Generalized estimating equation was used to compare OCT parameters between cases and controls, adjusted for covariates. Average ganglion cell-inner plexiform layer (GC-IPL) and average retinal nerve fibre layer (RNFL) thicknesses. We analyzed 227 cases and 227 controls. The mean age (years) of cases was 58.3 and controls was 58.1 (P = 0.13). Among cases, 101 had none, 25 had mild and 101 had moderate or severe DR. Compared with controls, GC-IPL and RNFL were thinner in all cases [mean difference (95% confidence interval [CI]): GC-IPL -4.49 µm (-2.92; -6.06), RNFL -0.93 µm (-0.09; -1.85)], including cases with no DR [mean difference (95% CI), GC-IPL -4.37 µm (-2.72; -6.02), RNFL -1.06 µm (-0.10; -2.02)]. Cases with any DR had thinner GC-IPL than controls [mean difference (95% CI): GC-IPL -4.81 µm (-2.12; -7.50)]. Among cases, subjects with moderate or severe DR had thinner GC-IPL than subjects with no DR [mean difference (95% CI): GC-IPL -2.07 µm (-0.08; -4.07)]. RGC loss is present in subjects with diabetes and no DR, and is progressive in moderate or severe DR. RGC neuronal damage in diabetes and DR can be clinically detected using OCT.

Identification of Diabetic Retinopathy and Ungradable Image Rate with Ultrawide Field Imaging in a National Teleophthalmology Program

To compare diabetic retinopathy (DR) identification and ungradable image rates between nonmydriatic ultrawide field (UWF) imaging and nonmydriatic multifield fundus photography (NMFP) in a large multistate population-based DR teleophthalmology program. Multiple-site, nonrandomized, consecutive, cross-sectional, retrospective, uncontrolled imaging device evaluation. Thirty-five thousand fifty-two eyes (17 526 patients) imaged using NMFP and 16 218 eyes (8109 patients) imaged using UWF imaging. All patients undergoing Joslin Vision Network (JVN) imaging with either NMFP or UWF imaging from May 1, 2014, through August 30, 2015, within the Indian Health Service-JVN program, which serves American Indian and Alaska Native communities at 97 sites across 25 states, were evaluated. All retinal images were graded using a standardized validated protocol in a centralized reading center. Ungradable rate for DR and diabetic macular edema (DME). The ungradable rate per patient for DR and DME was significantly lower with UWF imaging compared with NMFP (DR, 2.8% vs. 26.9% [P < 0.0001]; DME, 3.8% vs. 26.2% [P < 0.0001]). Identification of eyes with either DR or referable DR (moderate nonproliferative DR or DME or worse) was increased using UWF imaging from 11.7% to 24.2% (P < 0.0001) and from 6.2% to 13.6% (P < 0.0001), respectively. In eyes with DR imaged with UWF imaging (n= 3926 eyes of 2402 patients), the presence of predominantly peripheral lesions suggested a more severe level of DR in 7.2% of eyes (9.6% of patients). In a large, widely distributed DR ocular telehealth program, as compared with NMFP, nonmydriatic UWF imaging reduced the number of ungradable eyes by 81%, increased the identification of DR nearly 2-fold, and identified peripheral lesions suggesting more severe DR in almost 10% of patients, thus demonstrating significant benefits of this imaging method for large DR teleophthalmology programs.

The Effects of PASCAL Panretinal Photocoagulation on the Peripapillary Retinal Nerve Fiber Layer

Purpose: To investigate the effects of Pascal (Topcon Medical Laser Systems, Inc. Oakland, NJ) pan-retinal photocoagulation (PRP) on the optic nerve head (ONH). Method: This was a prospective case control study comparing 3 groups of patients seen in the diabetic retinopathy (DR) clinics, without any coexistent optic nerve pathology. Group A patients had proliferative or severe non proliferative DR necessitating PRP during the study period. Group B patients had mild or moderate DR and did not require PRP throughout the study period. Group C patients had standard retinal laser (green argon or frequency doubled YAG) PRP at least 2 years ago. All the 3 Groups had retinal oxygenation measurements and retinal vessel caliber readings by Oxymap T1(Oxymap, Reykjavik, Iceland), optic disc stereophotographs, high definition optical coherence tomography (HD-OCT) scans of the ONH by both Cirrus (Carl Zeiss Meditec Inc, Dublin, CA) and Spectralis (Heidelberg Engineering, Heidelberg Germany). These were performed prior to PRP at baseline, then at 3, 6, and 12 months post PRP for group A and at baseline, 3, 6, and 12 months for groups B and C. Paired t-test was used to assess the mean changes in parameters from baseline for each group. Results: A total of 90 patients were recruited including 27 in Group A, 31 in Group B and 32 in Group C. At baseline, the average retinal nerve fibre layer (RNFL) was significantly thicker in group A compared to group B (102.0 ± 16.8 vs. 89.5 ± 11.6 μm, p=0.001) and group C (88.6 ± 11.2 μm, p=0.001) respectively. At 3 months, Group A exhibited a significant increase in the Cirrus average RNFL thickness (5.60 ± 8.54 μ, p=0.003) when compared to baseline. At 6 months, the average RNFL reverted to baseline values (p=0.89), and remained stable at 12 months (p=0.85). There was no significant change noted in the average Cirrus RNFL thickness at 3 and 6 months in Group B. At 12 months, the average RNFL was significantly thinner compared to baseline (-6.68 ± 8.10; p=0.005). In Group C, the average RNFL remained stable from baseline through to month 12 (p>0.05 at the three timepoints). No significant changes were noted in the average Spectralis RNFL thickness at any timepoints in each of the three groups. Oxygen saturation dropped in all 3 groups at 3 months, being significant only in group B (-2.05 ± 4.20%, p=0.03). Conclusion: In eyes treated with Pascal PRP, there was an initial increase in the retinal nerve fibre layer at the optic nerve head at 3 months followed by a thinning back to baseline values at 6 months which then remained stable up to 12 months. Hence the Pascal PRP did not have a significant effect on the nerve fibre layer at 12 months.

Quantitative spectral domain optical coherence tomography thickness parameters in type II diabetes.

Purpose:To elucidate the changes in retinal thickness and individual layer thickness in subjects with diabetic retinopathy (DR) using spectral domain optical coherence tomography (SDOCT).Materials and Methods:A total of 251 eyes from 170 subjects were included in this study. The study sample was subdivided into nondiabetic subjects; subjects with diabetes but no DR; subjects with mild, moderate, and severe nonproliferative DR (NPDR); and proliferative DR. Various retinal thickness parameters were assessed using SDOCT.Results:The mean age of the study population was 55.34 ± 9.02 years (range: 32–80 years) and 56.6% of the subjects were males. Men had significantly greater central foveal thickness, central subfield thickness, retinal nerve fiber layer thickness, and retinal thickness in all the quadrants of 3 mm and 6 mm zones compared to women (P < 0.001). Superior (293.11 ± 25.46 vs. 285.25 ± 19.17; P = 0.044) and temporal (282.10 ± 25.26 vs. 272.46 ± 16.21; P = 0.011) quadrants showed an increased retinal thickness in any DR group when compared with diabetic subjects without DR. Photoreceptor layer thickness was significantly reduced in diabetic subjects with no DR when compared with nondiabetic subjects and also in cases of severe NPDR when compared with mild and moderate NPDR.Conclusion:Here, we analyze the quantitative retinal thickness parameters in diabetic subjects using SDOCT. Neuronal degenerative changes such as photoreceptor and retinal pigment epithelial thinning in case of DR are also reported.

Retinal Blood Flow and Retinal Blood Oxygen Saturation in Mild to Moderate Diabetic Retinopathy.

The aim of this study was to evaluate the relationship between retinal blood flow (RBF) and retinal blood oxygen saturation (SO2) in mild to moderate nonproliferative diabetic retinopathy (NPDR) and in age-matched controls. One eye of each of 15 healthy subjects (68 ± 6 years) and 13 subjects with mild to moderate NPDR (67 ± 10 years) was dilated. None of the patients with NPDR had received treatment for their retinopathic changes or had any evidence of sight-threatening characteristics. Doppler Fourier-domain optical coherence tomography blood flow was measured using the prototype RTVue system; six separate measurements each comprising an upper and a lower nasal pupil scan were acquired. Six hyperspectral retinal measurements were acquired using a noninvasive hyperspectral retinal camera (prototype H-8.5 HR Camera). Total RBF was significantly lower in NPDR when compared to controls (42.7 ± 7.5 vs. 33.0 ± 9.2 μL/min; P = 0.004). Mean retinal arterial and venular SO2 were higher in NPDR than in controls (94.7 ± 2.4% vs. 92.9 ± 1.6%, P = 0.02; 62.5 ± 5.7% vs. 56.3 ± 4.7%, P = 0.003). This study showed a correlation between RBF and arteriolar SO2 in both controls (r = 0.58, P = 0.02) and NPDR (r = 0.54, P = 0.05), but no correlation between venular RBF and venular SO2 in controls (r = 0.24, P = 0.83) or in NPDR (r = 0.23, P = 0.45). The arteriovenous difference (AV difference) was lower in the NPDR group when compared to controls (30.6 ± 6 vs. 36.7 ± 5.3, P = 0.008). This study found a lower total RBF and a lower AV difference in the NPDR group, suggesting a reduced oxygen uptake from the retina in people with relatively early diabetic retinopathy.

First Incidence and Progression Study for Diabetic Retinopathy in Portugal, the RETINODIAB Study: Evaluation of the Screening Program for Lisbon Region

To estimate the 5-year incidence and progression of diabetic retinopathy (DR) among persons with type 2 diabetes mellitus (DM). Population-based, prospective, cohort study. The RETINODIAB (Study Group for Diabetic Retinopathy Screening) program was implemented in the Lisbon and Tagus Valley area between July 2009 and December 2014. A total of 109 543 readable screening examinations were performed and corresponded to 56 903 patients who attended the screening program at entry. A total of 30 641 patients (53.85%) had at least 1 further screening event within the study period and were included in the analysis. Participants underwent two 45° nonstereoscopic retinal digital photographs per eye according to RETINODIAB protocol. All images were graded according to the International Clinical Diabetic Retinopathy Scale. Referable diabetic retinopathy (RDR) was defined for all patients graded as moderate nonproliferative DR (NPDR), severe NPDR, or proliferative DR (PDR), with or without maculopathy or mild NPDR with maculopathy. Nonparametric estimates of the annual and cumulative incidences were obtained by Turnbull's estimator. Associations between the potential risk factors and the time to onset/progression of retinopathy were assessed through a parametric survival analysis for interval-censored data. The authors estimated the onset and progression incidence rates of DR. Yearly incidence of any DR in patients without retinopathy at baseline was 4.60% (95% confidence interval [CI], 3.96-4.76) in the first year, decreasing to 3.87% (95% CI, 2.57-5.78) in the fifth year. In participants with mild NPDR at baseline, the progression rate to RDR in year 1 was 1.18% (95% CI, 0.96-1.33). Incidence of any DR and RDR and DR progression rate were associated with known duration of diabetes, age at diagnosis, and use of insulin treatment. This longitudinal epidemiologic study provides the first Portuguese incidence DR data in a large-scale population-based cohort of type 2 diabetes after a 5-year follow-up. Duration of diabetes, age at diagnosis, and insulin treatment were associated with increasing risk of incidence and progression of DR. A personalized schedule distribution of screening intervals according to the individual patient's profile should be implemented, with resulting benefits in terms of health costs.

The Association of Estimated Glomerular Filtration Rate With Diabetic Retinopathy and Macular Edema

Albuminuria, a marker of diabetic kidney disease, is closely associated with diabetic retinopathy (DR) and diabetic macular edema (DME). However, the relationship between estimated glomerular filtration rate (eGFR) with DR and DME remains unclear, particularly in type 2 diabetes. We investigated the association of eGFR with DR and DME in a sample of patients with type 2 diabetes. We included 263 Caucasian patients with type 2 diabetes aged ≥ 18 years who participated in a clinic-based cross-sectional study in Melbourne, Australia. Diabetic retinopathy (n = 140) and DME (n = 61) were assessed from retinal photographs graded using the modified Airlie House classification and further confirmed with optical coherence tomography. Estimated glomerular filtration rate, assessed using the CKD-EPI formula, was analyzed continuously (per SD change) and categorically (normal renal function ≥ 90; impaired renal function, 60-89, and chronic kidney disease [CKD] < 60 mL/min/1.73 m2). When eGFR was analyzed categorically, impaired renal function and CKD were associated with the presence of DR when compared to normal renal function in multivariable models (odds ratio [OR] with 95% confidence interval [CI] of 2.97 [1.12-7.87] and 3.77 [1.28-11.10]), respectively. In DR severity analyses, CKD showed significant associations with moderate (5.83 [1.44-23.5], P-trend = 0.02) and severe DR (4.91 [1.26-19.0], P-trend = 0.04). These associations persisted when eGFR was analyzed continuously (P = 0.04). No significant associations were found between eGFR and DME. Our results suggest that lower levels of eGFR were associated with the presence and severity of DR, but not with DME.

Multifocal Pupillography Identifies Changes in Visual Sensitivity According to Severity of Diabetic Retinopathy in Type 2 Diabetes.

Retinal light sensitivity loss has been shown to occur prior to other signs of retinopathy and may predict the sight-threatening sequelae. A rapid, objective perimetric test could augment diabetes care. We investigated the clinical use of multifocal pupillographic objective perimetry (mfPOP) to identify patients with and without diabetic retinopathy. Retinopathy severity was determined using the Early Treatment of Diabetic Retinopathy Study (ETDRS) standard for fundus photography. Pupillary responses were measured from both eyes of 25 adults with none to moderate diabetic retinopathy and 24 age-matched controls, using three mfPOP stimulus variants. Multifocal pupillographic objective perimetry stimulus variants tested 44 regions per eye arranged in a five-ring dartboard layout presented within either the central 30° or 60° of fixation. Receiver operator characteristic (ROC) curves were produced from contraction amplitudes and time to peak responses. Regression analysis revealed that mean amplitude deviations were larger with severity of early retinopathy. On average, the longest delays were measured in patients with no retinopathy. The brightest wide-field stimuli produced the highest area under the ROC curve for differentiating eyes with no retinopathy from nonproliferative diabetic retinopathy (NPDR) and from healthy eyes (100 ± 0.0%, mean ± SE). The asymmetry in local delay deviations between eyes tended to produce higher sensitivity and specificity than amplitude deviations. Asymmetry in local response delays measured by mfPOP may provide useful information regarding the severity of diabetic retinopathy and may have clinical use as a rapid, noninvasive method for identifying functional loss even in the absence of NPDR.

Proteomic analysis of plasma proteins in diabetic retinopathy patients by two dimensional electrophoresis and MALDI-Tof-MS

ObjectiveDiabetic retinopathy is a highly specific vascular complication of diabetes mellitus and progresses from mild non-proliferative abnormalities characterized by increased vascular permeability to moderate and severe proliferative diabetic retinopathy characterized by the growth of blood vessels on the retina. The aim of the study was to identify the differentially expressed proteins in diabetic retinopathy using two-dimensional electrophoresis. MethodsBlood sample was drawn from subjects with diabetes mellitus (without retinopathy) who served as controls and patients with diabetic retinopathy in tubes containing EDTA as anticoagulant. Albumin and immunoglobulin IgG collectively removed to enrich proteins of lower abundance. 2de was carried out to see if there are any differentially expressed proteins. ResultsApproximately 48 and 61 spots were identified in control and diabetic retinopathy respectively, of which three protein spots RBP1 (retinol-binding protein 1), NUD10 (Diphosphoinositol polyphosphohydrolase 3 alpha), NGB (neuroglobin) were down regulated and HBG2 (hemoglobin) and BY55 (CD 160 antigen) were upregulated in diabetic retinopathy.These five protein spots were excised and were subjected to in-gel tryptic digestion, and their identities were determined by ultraflex MALDI-TOF-MS. ConclusionWe report a comprehensive patient-based plasma proteomic approach to the identification of potential biomarkers for diabetic retinopathy screening and detection. Significance of the studyWe identified 5 different proteins that were differentially expressed in the plasma of control diabetic patients (without retinopathy). Among these five proteins the expression of neuroglobin (NGB) protein varied significantly and may be a potential biomarker in diabetic retinopathy.

CLINICAL COURSE OF DIABETIC RETINOPATHY IN KOREAN TYPE 2 DIABETES AFTER BARIATRIC SURGERY: A Pilot Study.

To assess the changes in diabetic retinopathy (DR) in Type 2 diabetes (T2DM) patients after bariatric surgery. Consecutive 20 patients with T2DM who underwent bariatric surgery and were followed for at least 12 months were enrolled. The case history was reviewed retrospectively, and laboratory data were assessed at baseline and every 3 months postoperatively. Two retinal specialists evaluated the severity of DR with dilated fundus examination preoperatively and postoperatively. Factors associated with DR progression were assessed. During the follow-up period, 2 of 12 patients without DR and 2 of 3 patients with mild nonproliferative DR before surgery developed moderate nonproliferative DR. All five patients with moderate nonproliferative DR or worse preoperatively had progression requiring intervention. Preexisting DR (P = 0.005) and albuminuria (P = 0.01) were identified as associated with DR progression. Six patients (30%) entered remission of T2DM, but remission of T2DM could not halt the DR progression. Diabetic retinopathy progression can occur in patients with or without before DR after bariatric surgery, regardless of remission of T2DM. All patients with T2DM should be examined regularly by an ophthalmologist postoperatively, and more carefully patients with previous DR or albuminuria.

Further insight on the limits of success of glycemic control in type 1 diabetes.

The successful extraction, purification, and use of insulin in the early 1900s led to greater survival in persons with type 1 diabetes as well as to a better understanding of the impact of diabetes on visual impairment and blindness (1). However, it was not until the completion of the Diabetes Control and Complications Trial (DCCT) that we fully understood the impact of the level of glycemia on the development of complications of diabetes, especially retinopathy (2). The DCCT was designed to assess the relationship between glycemic control and the development, progression, or amelioration of early vascular complications, such as retinopathy, in persons with type 1 diabetes. The trial recruited two groups of persons with type 1 diabetes: those with no complications of diabetes (the primary prevention group) and those with generally longer duration of diabetes and who had mild to moderate diabetic retinopathy and limited albumin excretion in the urine. The persons in these groups were randomly assigned to intensive or conventional diabetes therapy. The trial cohort was followed for a mean duration of 6.5 years. Development and progression of the severity of retinopathy were the primary end points. The trial was well designed and the outcome clearly demonstrated the beneficial effect of intensive glycemic control on the progression of diabetic retinopathy (2). This landmark trial informed and subsequently transformed the care of persons with type 1 diabetes. Patients in the general population were urged to self-monitor their levels of glycemia and to adjust their insulin doses accordingly (3,4). The functional impact seems …

Serum Cystatin C, Markers of Chronic Kidney Disease, and Retinopathy in Persons with Diabetes.

Purpose. We examined the association of CKD defined by serum creatinine, serum cystatin C, and albuminuria with moderate diabetic retinopathy (DR). Methods. We examined 1,119 Indian adults with diabetes, aged 40–80 years, who participated in the Singapore Indian Eye Study (2007–2009), a population-based cross-sectional study. The associations of CKD defined by each of the three markers alone and in combination with moderate DR were examined using logistic regression models adjusted for potential confounding factors including duration of diabetes, smoking, body mass index, systolic blood pressure, and HbA1c. Results. The prevalence of moderate DR was significantly higher among those with CKD defined by triple markers (41.1%) compared to CKD defined separately by creatinine (26.6%), cystatin C (20.9%), and albuminuria (23.4%). People with CKD defined by triple markers had a fourteenfold higher odds of moderate DR (OR (95% CI) = 13.63 (6.08–30.54)) compared to those without CKD by any marker. Nearly half (48.7%) of participants with cystatin C ≥ 1.12 mg/L have moderate DR. Conclusions. CKD defined by a triple marker panel was strongly associated with moderate DR in this Asian population with diabetes.

The optimal cutoff value of glycated hemoglobin for detection of diabetic retinopathy.

With standardization of measurement of glycated hemoglobin (A1C), the International Expert Committee Report in 2009 and the American Diabetes Association in 2010 recommended incorporating A1C ≥6.5% into the previous diagnostic criteria using fasting plasma glucose and/or 2-hour plasma glucose. Whereas the association of A1C with cardiovascular diseases and other diabetic microvascular complications was linear without evidence of a distinct threshold, several studies suggested a threshold value for A1C in diabetic retinopathy (DR). In studies about the optimal cutoff value for A1C in DR, the A1C values range from 5.2% to 7.8%. There are several possible reasons why these values for DR differ so widely (differences in the definition and/or methods for DR, variation in statistical methods, differences in study population, differences in exclusion criteria, and difference in methods for measuring A1C). With these wide variations in the study method, drawing a conclusive cutoff value for A1C in DR is impossible. In published studies, the cutoff values for moderate or severe DR were higher than those for any or mild DR (6.4% to 7.0% vs. 5.5% to 6.5%).

Relationship of systemic endothelial function and peripheral arterial stiffness with diabetic retinopathy

BackgroundTo investigate possible associations between diabetic retinopathy (DR) and systemic vascular endothelial function and arterial stiffness measured using reactive hyperaemia peripheral arterial tonometry.MethodsThis was a cross-sectional observational clinical study. Subjects...