Age at onset and the risk of proliferative retinopathy in type 1 diabetes

Advanced cardiovascular physiology in an individual with type 1 diabetes after 10-year ketogenic diet

Adults with type 1 diabetes (T1D) have an elevated risk for cardiovascular disease (CVD) compared with the general population. HbA1c is the primary modifiable risk factor for CVD in T1D. Fewer than 1% of patients achieve euglycemia (<5.7% HbA1c). Ketogenic diets (KD; ≤50 g carbohydrate/day) may improve glycemia and downstream vascular dysfunction in T1D by reducing HbA1c and insulin load. However, there are concerns regarding the long-term CVD risk from a KD. Therefore, we compared data collected in a 60-day window in an adult with T1D on exogenous insulin who consumed a KD for 10 years versus normative values in those with T1D (T1D norms). The participant achieved euglycemia with an HbA1c of 5.5%, mean glucose of 98 [5] mg/dL (median [interquartile range]), 90 [11]% time-in-range 70-180 mg/dL (T1D norms: 1st percentile for all), and low insulin requirements of 0.38 ± 0.03 IU/kg/day (T1D norms: 8th percentile). Seated systolic blood pressure (SBP) was 113 mmHg (T1D norms: 18th percentile), while ambulatory awake SBP was 132 ± 15 mmHg (T1D target: <130 mmHg), blood triglycerides were 69 mg/dL (T1D norms: 34th percentile), low-density lipoprotein was 129 mg/dL (T1D norms: 60th percentile), heart rate was 56 beats/min (T1D norms: >1SD below the mean), carotid-femoral pulse wave velocity was 7.17 m/s (T1D norms: lowest quartile of risk), flow-mediated dilation was 12.8% (T1D norms: >1SD above mean), and cardiac vagal baroreflex gain was 23.5 ms/mmHg (T1D norms: >1SD above mean). Finally, there was no indication of left ventricular diastolic dysfunction from echocardiography. Overall, these data demonstrate below-average CVD risk relative to T1D norms despite concerns regarding the long-term impact of a KD on CVD risk.NEW & NOTEWORTHY Adults with type 1 diabetes (T1D) have a 10-fold higher risk for cardiovascular disease (CVD) compared with the general population. We assessed cardiovascular health metrics in an adult with T1D who presented with a euglycemic HbA1c after following a ketogenic diet for the past 10 years. Despite concerns about the ketogenic diet increasing CVD risk, the participant exhibited below-average CVD risk relative to others with T1D when considering all outcomes together.

Are soluble E-selectin, ICAM-1, and VCAM-1 potential predictors for the development of diabetic retinopathy in young adults, 15-34 years of age? A Swedish prospective cohort study

The aim of this study was to determine plasma levels of three adhesion molecules that may contribute to the development of diabetic retinopathy; soluble endothelial selectin (sE-selectin), soluble intercellular adhesion molecule-1 (sICAM-1), and soluble vascular cell adhesion molecule-1 (sVCAM-1), in young adults, aged 15-34 years at diagnosis of diabetes, to find potential predictors for development of retinopathy, and to evaluate their relation to diabetes associated autoantibodies. Participants with type 1 (n = 169) and type 2 diabetes (n = 83) were selected from the complications trial of the Diabetes Incidence Study in Sweden and classified in two subgroups according to presence (n = 80) or absence (n = 172) of retinopathy as determined by retinal photography at follow-up 8-10 years after diagnosis of diabetes. Blood samples were collected at diagnosis in 1987-88. The levels of sE-selectin, sICAM-1, and sVCAM-1 were analysed by enzyme-linked immunosorbent assay and islet cell antibodies by a prolonged two-colour immunofluorescent assay. Mean HbA1c (p<0.001) and clinical characteristics: mean body mass index (p = 0.019), systolic blood pressure (p = 0.002), diastolic blood pressure (p = 0.003), male gender (p = 0.026), and young age at diagnosis of diabetes (p = 0.015) remained associated with development of retinopathy in type 1 diabetes. However, in a multivariate analysis only HbA1c remained as a risk factor. sE-selectin was significantly higher in the group with type 2 diabetes and retinopathy, compared to the group with type 2 diabetes without retinopathy (p = 0.04). Regarding sE-selectin, sICAM-1, and sVCAM-1 in participants with type 1 diabetes, no differences were observed between the groups with or without retinopathy. This trial confirmed the role of HbA1c and clinical characteristics as predictors for development of retinopathy in type 1 diabetes. sE-selectin stands out as a potential predictor for development of retinopathy in type 2 diabetes, whereas a predictive role for sICAM-1 and sVCAM-1 could not be identified neither for type 1 nor type 2 diabetes.

Global prevalence of erectile dysfunction and its associated risk factors among men with type 1 diabetes: a systematic review and meta-analysis

Various observational studies have examined the prevalence and determinants of erectile dysfunction (ED) in men with type 1 diabetes across different geographical areas. Nevertheless, a comprehensive systematic review and meta-analysis to consolidate the worldwide prevalence and risk factors remains lacking. Hence, the primary study objective was to perform an extensive systematic review and meta-analysis that specifically examined ED prevalence and determinants in men with type 1 diabetes. A thorough exploration was conducted by examining electronic databases, such as PubMed, Embase, and Web of Science. The general ED prevalence and a 95% confidence interval (CI) in men with type 1 diabetes were summarized. The relevant risk factors were analyzed by deriving a comprehensive odds ratio (OR) from merging the ORs using fixed- or random-effects models. The sources of heterogeneity were investigated using subgroup analyses and meta-regression. This systematic review and meta-analysis included 19 articles involving 3788 men with type 1 diabetes. The meta-analysis revealed that men with type 1 diabetes had a combined ED prevalence of 42.5% (95% CI: 34.3%-50.8%). This prevalence showed significant heterogeneity (I2 = 96.2%, P < 0.01). Meta-regression revealed that age (P = 0.016) and type 1 diabetes duration (P = 0.004) were significant causes of heterogeneity. Furthermore, the ED risk in men with type 1 diabetes was significantly influenced by age, type 1 diabetes duration, body mass index, glycated hemoglobin (HbA1c), retinopathy, and smoking habits (all P < 0.05). In summary, this systematic review and meta-analysis revealed a significant prevalence of ED in men with type 1 diabetes, highlighting the importance of clinicians addressing concerns regarding ED in this specific group of individuals.

Lifetime and 10-year cardiovascular risk prediction in individuals with type 1 diabetes: The LIFE-T1D model

AIMS

To develop and externally validate the LIFE-T1D model for the estimation of lifetime and 10-year risk of cardiovascular disease (CVD) in individuals with type 1 diabetes.

MATERIALS AND METHODS

A sex-specific competing risk-adjusted Cox proportional hazards model was derived in individuals with type 1 diabetes without prior CVD from the Swedish National Diabetes Register (NDR), using age as the time axis. Predictors included age at diabetes onset, smoking status, body mass index, systolic blood pressure, glycated haemoglobin level, estimated glomerular filtration rate, non-high-density lipoprotein cholesterol, albuminuria and retinopathy. The model was externally validated in the Danish Funen Diabetes Database (FDDB) and the UK Biobank.

RESULTS

During a median follow-up of 11.8 years (interquartile interval 6.1-17.1 years), 4608 CVD events and 1316 non-CVD deaths were observed in the NDR (n = 39 756). The internal validation c-statistic was 0.85 (95% confidence interval [CI] 0.84-0.85) and the external validation c-statistics were 0.77 (95% CI 0.74-0.81) for the FDDB (n = 2709) and 0.73 (95% CI 0.70-0.77) for the UK Biobank (n = 1022). Predicted risks were consistent with the observed incidence in the derivation and both validation cohorts.

CONCLUSIONS

The LIFE-T1D model can estimate lifetime risk of CVD and CVD-free life expectancy in individuals with type 1 diabetes without previous CVD. This model can facilitate individualized CVD prevention among individuals with type 1 diabetes. Validation in additional cohorts will improve future clinical implementation.

Chemokines in diabetic eye disease

BACKGROUND

Diabetic eye disease is a common micro-vascular complication of diabetes and a leading cause of decreased vision and blindness in people of working age worldwide.Although previous studies have shown that chemokines system may be a player in pathogenesis of diabetic eye disease, it is unclear which chemokines play the most important role.To date, there is no meta-analysis which has investigated the role of chemokines in diabetic eye disease.We hope this study will contribute to a better understanding of both the signaling pathways of the chemokines in the pathophysiological process, and more reliable therapeutic targets for diabetic eye disease.

METHODS

Embase, PubMed, Web of Science and Cochrane Library systematically searched for relevant studies from inception to Sep 1, 2023. A random-effect model was used and standardized mean differences (SMDs) and 95% confidence intervals (CIs) were calculated to summarize the associated measure between chemokines concentrations and diabetic eye disease. Network meta-analysis to rank chemokines-effect values according to ranked probabilities.

RESULTS

A total of 33 different chemokines involving 11,465 subjects (6559 cases and 4906 controls) were included in the meta-analysis. Results of the meta-analysis showed that concentrations of CC and CXC chemokines in the diabetic eye disease patients were significantly higher than those in the controls. Moreover, network meta-analysis showed that the effect of CCL8, CCL2, CXCL8 and CXCL10 were ranked highest in terms of probabilities. Concentrations of CCL8, CCL2, CXCL8 and CXCL10 may be associated with diabetic eye disease, especially in diabetic retinopathy and diabetic macular edema.

CONCLUSION

Our study suggests that CCL2 and CXCL8 may play key roles in pathogenesis of diabetic eye disease. Future research should explore putative mechanisms underlying these links, with the commitment to develop novel prophylactic and therapeutic for diabetic eye disease.

An Assay to Detect Protection of the Retinal Vasculature from Diabetes-Related Death in Mice

Diabetic retinopathy (DR) is a complex and progressive ocular disease characterized by two distinct phases in its pathogenesis. The first phase involves the loss of protection from diabetes-induced damage to the retina, while the second phase centers on the accumulation of this damage. Traditional assays primarily focus on evaluating capillary degeneration, which is indicative of the severity of damage, essentially addressing the second phase of DR. However, they only indirectly provide insights into whether the protective mechanisms of the retinal vasculature have been compromised. To address this limitation, a novel approach was developed to directly assess the retina's protective mechanisms - specifically, its resilience against diabetes-induced insults like oxidative stress and cytokines. This protection assay, although initially designed for diabetic retinopathy, holds the potential for broader applications in both physiological and pathological contexts. In summary, understanding the pathogenesis of diabetic retinopathy involves recognizing the dual phases of protection loss and damage accumulation, with this innovative protection assay offering a valuable tool for research and potentially extending to other medical conditions.

Pharmacotherapy and Nutritional Supplements for Neovascular Eye Diseases

In this review, we aim to provide an overview of the recent findings about the treatment of neovascular retinal diseases. The use of conventional drugs and nutraceuticals endowed with antioxidant and anti-inflammatory properties that may support conventional therapies will be considered, with the final aim of achieving risk reduction (prevention) and outcome improvement (cooperation between treatments) of such sight-threatening proliferative retinopathies. For this purpose, we consider a medicinal product one that contains well-defined compound(s) with proven pharmacological and therapeutic effects, usually given for the treatment of full-blown diseases. Rarely are prescription drugs given for preventive purposes. A dietary supplement refers to a compound (often an extract or a mixture) used in the prevention or co-adjuvant treatment of a given pathology. However, it must be kept in mind that drug-supplement interactions may exist and might affect the efficacy of certain drug treatments. Moreover, the distinction between medicinal products and dietary supplements is not always straightforward. For instance, melatonin is formulated as a medicinal product for the treatment of sleep and behavioral problems; at low doses (usually below 1 mg), it is considered a nutraceutical, while at higher doses, it is sold as a psychotropic drug. Despite their lower status with respect to drugs, increasing evidence supports the notion of the beneficial effects of dietary supplements on proliferative retinopathies, a major cause of vision loss in the elderly. Therefore, we believe that, on a patient-by-patient basis, the administration of nutraceuticals, either alone or in association, could benefit many patients, delaying the progression of their disease and likely improving the efficacy of pharmaceutical drugs.

The Slow Progression of Diabetic Retinopathy Is Associated with Transient Protection of Retinal Vessels from Death

The purpose of this study was to investigate the reason that diabetic retinopathy (DR) is delayed from the onset of diabetes (DM) in diabetic mice. To this end, we tested the hypothesis that the deleterious effects of DM are initially tolerated because endogenous antioxidative defense is elevated and thereby confers resistance to oxidative stress-induced death. We found that this was indeed the case in both type 1 DM (T1D) and type 2 DM (T2D) mouse models. The retinal expression of antioxidant defense genes was increased soon after the onset of DM. In addition, ischemia/oxidative stress caused less death in the retinal vasculature of DM versus non-DM mice. Further investigation with T1D mice revealed that protection was transient; it waned as the duration of DM was prolonged. Finally, a loss of protection was associated with the manifestation of both neural and vascular abnormalities that are diagnostic of DR in mice. These observations demonstrate that DM can transiently activate protection from oxidative stress, which is a plausible explanation for the delay in the development of DR from the onset of DM.

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

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

Estimated glucose disposal rate is associated with retinopathy and kidney disease in young people with type 1 diabetes: a nationwide observational study

AIMS

The aim of this study was to investigate the association between estimated glucose disposal rate (eGDR), a proxy for insulin resistance, and retinopathy or kidney disease, i.e. micro-, or macroalbuminuria, in young individuals with type 1 diabetes (T1D).

MATERIAL AND METHODS

Using data from the Swedish pediatric registry for diabetes (SweDiabKids) and the registry for adults (NDR), all individuals with T1D with a duration of diabetes of less than 10 years between 1998 and 2017 were included. We calculated the crude incidence rates with 95% confidence intervals (CIs) and used multivariable Cox regression to estimate crude and adjusted hazard ratios (HRs) for two cohorts: retinopathy cohort or kidney disease cohort, stratified by eGDR categories: < 4, 4 to 5.99, 6 to 7.99, and ≥ 8 mg/kg/min (reference).

RESULTS

A total of 22 146 (10 289 retinopathy cohort, and 11 857 kidney disease cohort with an overlapping of 9575) children and adults with T1D (median age 21 years, female 42% and diabetes duration of 6 and 7 years, respectively for the cohorts) were studied. During a median follow-up of 4.8 years (IQR 2.6-7.7) there were 5040 (24.7%), 1909 (48.1%), 504 (52.3%) and 179 (57.6%) events for retinopathy in individuals with an eGDR ≥ 8, 7.99 to 6, 5.99 to 4, and < 4 mg/kg/min, respectively. Corresponding numbers for kidney disease was 1321 (6.5%), 526 (13.3%), 255 (26.8%) and 145 (46.6%). After multiple adjustments for different covariates, individuals with an eGDR 7.99 to 6, 5.99 to 4 and < 4 mg/kg/min, had an increased risk of retinopathy compared to those with an eGDR ≥ 8 mg/kg/min (adjusted HRs, 95% CIs) 1.29 (1.20 to 1.40); 1.50 (1.31 to 1.71) and 1.74 (1.41 to 2.14). Corresponding numbers for kidney disease was (adjusted HRs, 95% CIs) 1.30 (1.11 to 1.52); 1.58 (1.25 to 1.99) and 1.33 (0.95 to 1.86), respectively.

CONCLUSIONS

eGDR, a proxy for insulin resistance, is associated with retinopathy and kidney disease in young adults with T1D. The risk of retinopathy increased with lower eGDR. The risk of kidney disease also increased with lower eGDR; however results show no association between the lowest eGDR and kidney disease. eGDR can be helpful to identify young T1D individuals at risk.

Combining transfer learning with retinal lesion features for accurate detection of diabetic retinopathy

Diabetic retinopathy (DR) is a late microvascular complication of Diabetes Mellitus (DM) that could lead to permanent blindness in patients, without early detection. Although adequate management of DM via regular eye examination can preserve vision in in 98% of the DR cases, DR screening and diagnoses based on clinical lesion features devised by expert clinicians; are costly, time-consuming and not sufficiently accurate. This raises the requirements for Artificial Intelligent (AI) systems which can accurately detect DR automatically and thus preventing DR before affecting vision. Hence, such systems can help clinician experts in certain cases and aid ophthalmologists in rapid diagnoses. To address such requirements, several approaches have been proposed in the literature that use Machine Learning (ML) and Deep Learning (DL) techniques to develop such systems. However, these approaches ignore the highly valuable clinical lesion features that could contribute significantly to the accurate detection of DR. Therefore, in this study we introduce a framework called DR-detector that employs the Extreme Gradient Boosting (XGBoost) ML model trained via the combination of the features extracted by the pretrained convolutional neural networks commonly known as transfer learning (TL) models and the clinical retinal lesion features for accurate detection of DR. The retinal lesion features are extracted via image segmentation technique using the UNET DL model and captures exudates (EXs), microaneurysms (MAs), and hemorrhages (HEMs) that are relevant lesions for DR detection. The feature combination approach implemented in DR-detector has been applied to two common TL models in the literature namely VGG-16 and ResNet-50. We trained the DR-detector model using a training dataset comprising of 1,840 color fundus images collected from e-ophtha, retinal lesions and APTOS 2019 Kaggle datasets of which 920 images are healthy. To validate the DR-detector model, we test the model on external dataset that consists of 81 healthy images collected from High-Resolution Fundus (HRF) dataset and MESSIDOR-2 datasets and 81 images with DR signs collected from Indian Diabetic Retinopathy Image Dataset (IDRID) dataset annotated for DR by expert. The experimental results show that the DR-detector model achieves a testing accuracy of 100% in detecting DR after training it with the combination of ResNet-50 and lesion features and 99.38% accuracy after training it with the combination of VGG-16 and lesion features. More importantly, the results also show a higher contribution of specific lesion features toward the performance of the DR-detector model. For instance, using only the hemorrhages feature to train the model, our model achieves an accuracy of 99.38 in detecting DR, which is higher than the accuracy when training the model with the combination of all lesion features (89%) and equal to the accuracy when training the model with the combination of all lesions and VGG-16 features together. This highlights the possibility of using only the clinical features, such as lesions that are clinically interpretable, to build the next generation of robust artificial intelligence (AI) systems with great clinical interpretability for DR detection. The code of the DR-detector framework is available on GitHub at https://github.com/Janga-Lab/DR-detector and can be readily employed for detecting DR from retinal image datasets.

Impact of HbA1c Followed 32 Years From Diagnosis of Type 1 Diabetes on Development of Severe Retinopathy and Nephropathy: The VISS Study

OBJECTIVE

To evaluate HbA1c followed from diagnosis, as a predictor of severe microvascular complications (i.e., proliferative diabetic retinopathy [PDR] and nephropathy [macroalbuminuria]).

RESEARCH DESIGN AND METHODS

In a population-based observational study, 447 patients diagnosed with type 1 diabetes before 35 years of age from 1983 to 1987 in southeast Sweden were followed from diagnosis until 2019. Long-term weighted mean HbA1c (wHbA1c) was calculated by integrating the area under all HbA1c values. Complications were analyzed in relation to wHbA1c categorized into five levels.

RESULTS

After 32 years, 9% had no retinopathy, 64% non-PDR, and 27% PDR, and 83% had no microalbuminuria, 9% microalbuminuria, and 8% macroalbuminuria. Patients with near-normal wHbA1c did not develop PDR or macroalbuminuria. The lowest wHbA1c values associated with development of PDR and nephropathy (macroalbuminuria) were 7.3% (56 mmol/mol) and 8.1% (65 mmol/mol), respectively. The prevalence of PDR and macroalbuminuria increased with increasing wHbA1c, being 74% and 44% in the highest category, wHbA1c >9.5% (>80 mmol/mol). In comparison with the follow-up done after 20-24 years' duration, the prevalence of PDR had increased from 14 to 27% and macroalbuminuria from 4 to 8%, and both appeared at lower wHbA1c values.

CONCLUSIONS

wHbA1c followed from diagnosis is a very strong biomarker for PDR and nephropathy, the prevalence of both still increasing 32 years after diagnosis. To avoid PDR and macroalbuminuria in patients with type 1 diabetes, an HbA1c <7.0% (53 mmol/mol) and as normal as possible should be recommended when achievable without severe hypoglycemia and with good quality of life.

Cardiac Autonomic Nerve Dysfunction Predicts Incident Retinopathy and Early Kidney Dysfunction in Adolescents With Type 1 Diabetes

OBJECTIVE

Cardiac autonomic neuropathy (CAN) may contribute to vascular complications in diabetes. We hypothesized that adolescents with CAN are at greater risk of diabetic retinopathy and early kidney dysfunction.

RESEARCH DESIGN AND METHODS

In this prospective longitudinal study of 725 adolescents with type 1 diabetes without retinopathy and albuminuria at baseline, early CAN was defined as one or more abnormalities in seven heart rate tests derived from a 10-min electrocardiogram. Retinopathy was defined as the presence of one or more microaneurysms, early kidney dysfunction as an albumin excretion rate (AER) >7.5 μg/min, and albuminuria as an AER >20 μg/min. Multivariable generalized estimating equations were used to examine the association between CAN and retinopathy or early kidney dysfunction. Cox proportional hazards regression analysis was used to assess cumulative risks of incident retinopathy and albuminuria.

RESULTS

At baseline, the mean age of the sample was 13.6 ± 2.6 years, 52% were male, and mean diabetes duration was 6.1 ± 3.3 years. Over a median follow-up of 3.8 (interquartile range 2.2-7.5) years, the complication rate 27% for retinopathy, 16% for early kidney dysfunction, and 3% for albuminuria. The mean study HbA1c was 72.3 ± 16 mmol/mmol (8.6 ± 1.4%). CAN predicted incident retinopathy (odds ratio 2.0 [95% CI 1.4, 2.9]) and early kidney dysfunction (1.4 [1.0, 2.0]) after adjusting for HbA1c and diabetes duration. CAN also predicted retinopathy (hazard ratio 1.57 [95% CI 1.09, 2.26]) and albuminuria (2.30 [1.05, 5.04]) independently of HbA1c.

CONCLUSIONS

CAN predicted incident retinopathy and kidney dysfunction in adolescents with type 1 diabetes, likely reflecting autonomic microvascular dysregulation contributing to complications. Therefore, screening and interventions to reduce CAN may influence the risk of complications.

Improving the screening of risk factors in diabetic retinopathy

INTRODUCTION

In 2002, Diabetic Retinopathy was reported as the leading cause of blindness in the working age group. The introduction of systematic screening programs in the UK has reduced visual loss and blindness due to diabetic retinopathy, but it does still occur with catastrophic consequences for the individual.

AREAS COVERED

The author conducted an ongoing search for articles relating to diabetic retinopathy since 2000 utilizing Zetoc Alert with keywords and contents page lists from relevant journals. This review covers the risk factors for loss of vision due to diabetic retinopathy and discusses ways in which the awareness of these risk factors can be used to further reduce visual loss. Some risk factors such as glycemic and B/P control are well known from landmark trials. This review has included these factors but concentrated more on the evidence behind those risk factors that are not so clearly defined or so well known.

EXPERT OPINION

The major risk factors are well known, but one continues to find that people with diabetes lose vision in situations in which a better awareness of the risks by both the individual with diabetes and the health workers involved may have prevented the visual loss.

HDL cholesterol is a protective predictor in the development and progression of retinopathy in type 1 diabetes: A 15-year follow-up study

AIMS

To evaluate the 15-year incidence of development and progression of diabetic retinopathy (DR) in type 1 diabetic patients (T1DM) and determine the associated risk factors.

METHODS

123 T1DM were included in this prospective cohort study and followed for 15 years. Demographic, clinical, laboratory parameters, and retinal photographs were collected and analyzed. Risk factors for DR development and progression were identified using Cox regression analysis.

RESULTS

At baseline, 87 (71%) patients had no DR, and 36 (29%) had nonproliferative DR (NPDR). After 15 years, 54 patients (43.9%; 29.3/1000 person-years) developed NPDR or progressed to proliferative DR (PDR); 24 (27.6%) developed new NPDR, and 30 (83.3%) progressed to PDR. HbA₁c (HR = 1.48, p = 0.008) and urinary albumin excretion rate (AER) (HR = 1.58, p = 0.045) were associated with the risk of DR development and progression, and a protective association was found for HDL cholesterol (HR = 0.17, p = 0.021). The presence of DR at baseline (HR = 2.95, p = 0.023) was associated with the risk of its progression to PDR.

CONCLUSIONS

The 15-year incidence of DR development and progression in T1DM is still very high, which points to the need for close monitoring of T1DM, especially those with higher HbA₁c, higher AER, the initial presence of DR, and lower HDL cholesterol.

In Vivo Capillary Structure and Blood Cell Flux in the Normal and Diabetic Mouse Eye

Purpose

To characterize the early structural and functional changes in the retinal microvasculature in response to hyperglycemia in the Ins2^Akita mouse.

Methods

A custom phase-contrast adaptive optics scanning light ophthalmoscope was used to image retinal capillaries of 9 Ins2^Akita positive (hyperglycemic) and 9 Ins2^Akita negative (euglycemic) mice from postnatal weeks 5 to 18. A 15 kHz point scan was used to image capillaries and measure red blood cell flux at biweekly intervals; measurements were performed manually. Retinal thickness and fundus photos were captured monthly using a commercial scanning laser ophthalmoscope/optical coherence tomography. Retinal thickness was calculated using a custom algorithm. Blood glucose and weight were tracked throughout the duration of the study.

Results

Elevated blood glucose (>250 mg/dL) was observed at 4 to 5 weeks of age in Ins2^Akita mice and remained elevated throughout the study, whereas euglycemic littermates maintained normal glucose levels. There was no significant difference in red blood cell flux, capillary anatomy, lumen diameter, or occurrence of stalled capillaries between hyperglycemic and euglycemic mice between postnatal weeks 5 and 18. Hyperglycemic mice had a thinner retina than euglycemic littermates (p < 0.001), but retinal thickness did not change with duration of hyperglycemia despite glucose levels that were more than twice times normal.

Conclusions

In early stages of hyperglycemia, retinal microvasculature structure (lumen diameter, capillary anatomy) and function (red blood cell flux, capillary perfusion) were not impaired despite 3 months of chronically elevated blood glucose. These findings suggest that hyperglycemia alone for 3 months does not alter capillary structure or function in profoundly hyperglycemic mice.

Waist-Height Ratio and the Risk of Severe Diabetic Eye Disease in Type 1 Diabetes: A 15-Year Cohort Study

CONTEXT

Obesity prevalence has increased in type 1 diabetes (T1D). However, the relationship between body composition and severe diabetic eye disease (SDED) is unknown.

OBJECTIVE

To investigate the associations between body composition and SDED in adults with T1D.

METHODS

From 5401 adults with T1D in the Finnish Diabetic Nephropathy Study, we assessed 3468, and 437 underwent dual-energy X-ray absorptiometry for body composition analysis. The composite outcome was SDED, defined as proliferative retinopathy, laser treatment, antivascular endothelial growth factor treatment, diabetic maculopathy, vitreous hemorrhage, and vitrectomy. Logistic regression analysis evaluated the associations between body composition and SDED. Multivariable Cox regression analysis assessed the associations between the anthropometric measures and SDED. Subgroup analysis was performed by stages of albuminuria. The relevance ranking of each variable was based on the z statistic.

RESULTS

During a median follow-up of 14.5 (interquartile range 7.8-17.5) years, 886 SDED events occurred. Visceral/android fat ratio was associated with SDED [odds ratio (OR) 1.40, z = 3.13], as well as the percentages of visceral (OR 1.80, z = 2.45) and android fat (OR 1.28, z = 2.08) but not the total body fat percentage. Waist-height ratio (WHtR) showed the strongest association with the SDED risk [hazard ratio (HR) = 1.28, z = 3.73], followed by the waist (HR 1.01, z = 3.03), body mass index (HR 1.03, z = 2.33), and waist-hip ratio (HR 1.15, z = 2.22). The results were similar in normo- and microalbuminuria but not significant in macroalbuminuria. A WHtR ≥ 0.5 increased the SDED risk by 28% at the normo- and microalbuminuria stages.

CONCLUSIONS

WHtR, a hallmark of central obesity, is associated with SDED in individuals with T1D.

The natural history of emerging diabetic retinopathy and microalbuminuria from prepuberty to early adulthood in Type 1 diabetes: A 19-year prospective clinical follow-up study

OBJECTIVE

To evaluate the impact of long-term glycaemic control and glycaemic variability on microvascular complications in adolescents and young adults with childhood-onset Type 1 diabetes.

METHODS

Twenty-six participants took part in a prospective follow-up study. We used univariate generalised estimating equations (GEE) analysis with first-order autoregressive AR(1) covariance structure for repeated measurements to evaluate the relationship between emerging diabetic retinopathy (DR) and each single explanatory variable, namely age at developmental stages from late prepuberty until early adulthood, duration of diabetes and long-term HbA_1c . Thereafter, the simultaneous effect of these three explanatory variables to DR was analysed in a multivariate model.

RESULTS

Twenty-five participants developed DR by early adulthood after a median diabetes duration of 16.2 years (range 6.3-24.0). No participants had DR during prepuberty. Each of the three variables was independently associated with emerging DR: age (OR 1.47, 95% CI to 1.25 to 1.74, p < 0.001) stronger than diabetes duration (OR 1.42, 95% CI 1.23 to 1.63, p < 0.001) and HbA_1c (OR 1.02, 95% CI 1.001 to 1.05, p = 0.041) in this population. In the multivariate analysis of these three explanatory variables, only age was associated with DR (adjusted OR 1.52, 95% CI 1.10 to 2.10, p = 0.012).

CONCLUSIONS

The emergence of DR during adolescence and early adulthood is not rare and increases with age in patients with deteriorating metabolic control during puberty and thereafter. This underpins the need to prevent deterioration of glycaemic control from taking place during puberty-seen again in this follow-up study-in children with diabetes.

Early microvascular complications in type 1 and type 2 diabetes: recent developments and updates

The prevalence of youth-onset diabetes is progressing rapidly worldwide, and poor glycemic control, in combination with prolonged diabetes duration and comorbidities including hypertension, has led to the early development of microvascular complications including diabetic kidney disease, retinopathy, and neuropathy. Pediatric populations with type 1 (T1D) and type 2 (T2D) diabetes are classically underdiagnosed with microvascular complications, and this leads to both undertreatment and insufficient attention to the mitigation of risk factors that could help attenuate further progression of complications and decrease the likelihood for long-term morbidity and mortality. This narrative review aims to present a comprehensive summary of the epidemiology, risk factors, symptoms, screening practices, and treatment options, including future opportunities for treatment advancement, for microvascular complications in youth with T1D and T2D. We seek to uniquely focus on the inherent challenges of managing pediatric populations with diabetes and discuss the similarities and differences between microvascular complications in T1D and T2D, while presenting a strong emphasis on the importance of early identification of at-risk youth. Further investigation of possible treatment mechanisms for microvascular complications in youth with T1D and T2D through dedicated pediatric outcome trials is necessary to target the brief window where early pathological vascular changes may be significantly attenuated.

Sight-threatening retinopathy in nine adolescents with early onset type 1 diabetes

In adults, there has been a decline in the incidence of diabetic retinopathy (DR) associated with improvements in diabetes management. Data on incident severe DR in adolescents are sparse. In our established diabetes complications assessment service, we recorded nine cases of sight-threatening retinopathy in youth aged 15-17.9 years from 2017 to 2021. Proliferative retinopathy and clinically significant macular oedema were identified. The subjects were diagnosed with type 1 diabetes before the age of 10 years and had a history of poor glycaemic control (HbA1c 86-130 mmol/mol, 10%-15%). Five cases of retinopathy developed rapidly within 2.5 years of a previously normal retinal examination on seven-field stereoscopic retinal photography. Three adolescents required laser photocoagulation therapy. Two adolescents were diagnosed with retinopathy following improvement in diabetes control after being lost to medical follow-up and their retinopathy improved with improved glycaemic control. Thus, we support repeated retinal screening in adolescents with diabetes duration >10 years with suboptimal glycaemic control, even when initial retinal examination is normal, as retinopathy can progress rapidly during adolescence.

Choroidal thickness in children with type 1 diabetes depending on the pubertal status and metabolic parameters analyzed by optical coherence tomography

To assess choroidal thickness (CT) in children with type 1diabetes (T1D) regarding their pubertal status and seek for factors influencing this parameter, using optical coherence tomography.

MATERIAL AND METHODS

333 eyes out of 167 children with T1D without symptoms of diabetic retinopathy (mean age 12.81 ± 3.63 years, diabetes duration 4.59 ± 3.71 years) were enrolled. CT in all quadrants was evaluated. The studied population was divided into three groups: prepubertal, pubertal and postpubertal. The multivariate regression model was carried out using all metabolic parameter and then it was built using only the significant ones.

RESULTS

Significant differences in CT between males and females, except nasal and superior quadrants were observed. We revealed significant differences in CT between the three independent groups (Chi-square 18.6, p < 0.0001). In the statistically significant multiple regression model (R = 0.9, R² = 0.82, p < 0.0000), the serum level of free thyroxine, triiodothyronine, total hemoglobin, uric acid, low- and high-density cholesterol, daily insulin dose per kilogram, weight and level of vitamin D were significant.

CONCLUSION

In our studied group CT increases during puberty. Metabolic parameters such as cholesterol, uric acid, thyroid hormones, and hemoglobin concentration even within the normal range, significantly influence the CT, and these factors likely affect other blood vessels in the body.

Long-term complications of type 1 diabetes: what do we know and what do we need to understand?

Long-term complications of type 1 diabetes (T1D) include microvascular complications and macrovascular disease. Despite the important advances in the treatment of T1D of the last decades, these complications still represent the leading cause of morbidity and mortality in patients with T1D. Extensive evidence indicates that structural and functional alterations of the kidney, retina, nerves and large arteries occur already in the first years after the onset of diabetes. We performed a comprehensive review of the available evidence on screening, diagnosis, prevention and treatment of vascular complications of T1D. In particular, we focused on three major challenges related to long-term complications of T1D: 1) finding of new biomarkers and diagnostic methods able to identify early signs of complications; 2) identifying specific risk factors for the development of these complications; 3) identifying and implementing new therapeutic strategies able to prevent the development and progression of vascular complications.

Remnant cholesterol predicts progression of diabetic nephropathy and retinopathy in type 1 diabetes

BACKGROUND

We aimed to assess whether remnant cholesterol concentration and variability predict the progression of diabetic nephropathy (DN) and severe diabetic retinopathy (SDR) in type 1 diabetes.

METHODS

This observational prospective study covered 5150 FinnDiane Study participants. Remnant cholesterol was calculated as total cholesterol - LDL cholesterol - HDL cholesterol and variability as the coefficient of variation. DN category was based on consensus albuminuria reference limits and the progression status was confirmed from medical files. SDR was defined as retinal laser treatment. For 1338 individuals, the severity of diabetic retinopathy (DR) was graded using the ETDRS classification protocol. Median (IQR) follow-up time was 8.0 (4.9-13.7) years for DN and 14.3 (10.4-16.3) for SDR.

RESULTS

Remnant cholesterol (mmol L^-1 ) was higher with increasing baseline DN category (P < 0.001). A difference was also seen comparing non-progressors (0.41 [0.32-0.55]) with progressors (0.55 [0.40-0.85]), P < 0.001. In a Cox regression analysis, remnant cholesterol predicted DN progression, independently of diabetes duration, sex, HbA_1c , systolic blood pressure, smoking, BMI, estimated glucose disposal rate and estimated glomerular filtration rate (HR: 1.51 [1.27-1.79]). Remnant cholesterol was also higher in those who developed SDR (0.47 [0.36-0.66]) than those who did not (0.40 [0.32-0.53]), P < 0.001, and the concentration increased stepwise with increasing DR severity (P < 0.001). Regarding SDR, the HR for remnant cholesterol was 1.52 (1.26-1.83) with the most stringent adjustment. However, remnant cholesterol variability was not independently associated with the outcomes.

CONCLUSIONS

Remnant cholesterol concentration, but not variability, predicts DN progression and development of SDR. However, it remains to be elucidated whether the associations are causal or not.

Risk factors associated with retinopathy in young people with type 1 diabetes in Bangladesh

Objectives

Diabetic retinopathy (DR) is the most common microvascular complications seen in children and adolescents with type 1 diabetes. The aim of this study was to evaluate the prevalence of retinopathy and its association with other risk factors in young people with type 1 diabetes.

Methods

This study was a cross-sectional study, which was done as part of the ongoing complication assessment in the paediatric diabetes clinic in BIRDEM (Bangladesh Institute of Research and Rehabilitation of Diabetes Endocrine and Metabolic Disorders), a tertiary care hospital. Children, adolescents and young adults with type 1 diabetes who were having diabetes duration >2 years were included in this study. Retinopathy was detected using fundal photography, and grading was done by National Screening Committee of UK by trained ophthalmologists.

Results

Diabetic retinopathy was observed in 44 (6.6%) patients. Majority (95.4%) of them had early diabetic retinopathy in the form of mild NPDR (nonproliferative diabetic retinopathy) (R1). Patients with retinopathy had higher HbA1c 9.6[8.4-12.3] vs 9.1 [7.9-10.8] (P = .013), longer duration of diabetes 7.6 [5.5-10.7] vs 6.0 [4.5-8.2] years (P = .001) and were older 21.5 [18.0-23.0] vs 18 [16.0-21.0] years (P = .0001) compared with those without retinopathy. On multivariate regression analysis, higher age and median HbA1c were significantly associated with DR.

Conclusions

Higher HbA1c was the only modifiable risk factor for development of DR in our study population. Early detection of DR with improvement of glycaemic control may reduce the risk of progression of severe stages of the disease.

Influence of puberty on retinal microcirculation in children with type 1 diabetes without retinopathy using optical coherence tomography angiography

BACKGROUND

This study aimed to assess the influence of pubertal status on the results of optical coherence tomography angiography (OCTA) in children with type 1 diabetes (T1D).

METHODS

We enrolled 167 consecutive children with T1D. Retinal superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density data underwent analysis. We divided the study population into three subgroups depending on the pubertal status.

RESULTS

Analysis of the prepubertal and pubertal subgroups revealed statistically significant differences in foveal thickness (FT) (p < 0.05) and foveal SCP (p < 0.02). Analyzing subgroups of the prepubertal and postpubertal children, we observed statistically significant differences in FT (p < 0.03), whole SCP (p < 0.02), and foveal SCP (p < 0.02). Comparison of the pubertal and postpubertal subjects revealed differences in parafoveal DCP (p < 0.003). In the groups matched depending on diabetes duration, we observed differences between prepubertal, pubertal, and postpubertal children in FT, PFT, and parafoveal SCP and DCP.

CONCLUSION

Our data suggest that in a cohort of pubertal children with a short duration of diabetes, alterations in retinal vessel density occur early and progress during puberty.

Sustained Inhibition of NF-κB Activity Mitigates Retinal Vasculopathy in Diabetes

This study investigated the effects of long-term NF-κB inhibition in mitigating retinal vasculopathy in a type 1 diabetic mouse model (Akita, Ins2^Akita). Akita and wild-type (C57BL/6J) male mice, 24 to 26 weeks old, were treated with or without a selective inhibitor of NF-κB, 4-methyl-N1-(3-phenyl-propyl) benzene-1,2-diamine (JSH-23), for 4 weeks. Treatment was given when the mice were at least 24 weeks old. Metabolic parameters, key inflammatory mediators, blood-retinal barrier junction molecules, retinal structure, and function were measured. JSH-23 significantly lowered basal glucose levels and intraocular pressure in Akita. It also mitigated vascular remodeling and microaneurysms significantly. Optical coherence tomography of untreated Akita showed thinning of retinal layers; however, treatment with JSH-23 could prevent it. Electroretinogram demonstrated that A- and B-waves in Akita were significantly smaller than in wild type mice, indicating that JSH-23 intervention prevented loss of retinal function. Protein levels and gene expression of key inflammatory mediators, such as NOD-like receptor family pyrin domain-containing 3, intercellular adhesion molecule-1, inducible nitric oxide synthase, and cyclooxygenase-2, were decreased after JSH-23 treatment. At the same time, connexin-43 and occludin were maintained. Vision-guided behavior also improved significantly. The results show that reducing inflammation could protect the diabetic retina and its vasculature. Findings appear to have broader implications in treating not only ocular conditions but also other vasculopathies.

Looking Ahead: Visual and Anatomical Endpoints in Future Trials of Diabetic Macular Ischemia

Diabetic macular ischemia (DMI) is a common complication of diabetic retinopathy that can lead to progressive and irreversible visual loss. Despite substantial clinical burden, there are no treatments for DMI, no validated clinical trial endpoints, and few clinical trials focusing on DMI. Therefore, generating consensus on validated endpoints that can be used in DMI for the development of effective interventions is vital. In this review, we discuss potential endpoints appropriate for use in clinical trials of DMI, and consider the data required to establish acceptable and meaningful endpoints. A combination of anatomical, functional, and patient-reported outcome measures will provide the most complete picture of changes that occur during the progression of DMI. Potential endpoint measures include change in size of the foveal avascular zone measured by optical coherence tomography angiography and change over time in best-corrected visual acuity. However, these endpoints must be supported by further research. We also recommend studies to investigate the natural history and progression of DMI. In addition to improving understanding of how patient demographics and comorbidities such as diabetic macular edema affect clinical trial endpoints, these studies would help to build the consensus definition of DMI that is currently missing from clinical practice and research.

Early Onset Age Increased the Risk of Diabetic Retinopathy in Type 2 Diabetes Patients with Duration of 10-20 Years and HbA1C ≥7%: A Hospital-Based Case-Control Study

BACKGROUND

The relationship between onset age of diabetes and diabetic retinopathy (DR) is controversy and not concluded. Therefore, this hospital-based case-control study aimed to investigate the influence of diabetes onset age on the development of DR in patients with type 2 diabetes (T2D), independent of diabetic duration and HbA1c levels.

METHODS

A sample of 780 T2D patients with diabetic duration of 10-20 years and glycated hemoglobin (HbA1c) ≥7% were enrolled in the study. 338 T2D patients with onset age ≤45 years were further selected as cases (early onset) and 79 with onset age ≥ 55 years were chosen as controls (elderly onset). International Clinical Diabetic Retinopathy Disease Severity Scale was applied to estimate the severity of DR.

RESULTS

The prevalence of DR and proliferative diabetic retinopathy (PDR) was notably increased in the early onset group. When stratified by duration of diabetes, the impact of younger age on the risk of DR turned to be greatest in patients with diabetic duration ≥15 years (OR = 5.202, 95% CI 2.625-10.310). In groups stratified by HbA1c, the risk of DR was highest in patients with younger onset age and HbA1c ≥ 9% (OR = 3.889, 95% CI 1.852-8.167). Compared with the elderly onset group, the risk of DR (OR = 1.776, 95% CI = 1.326-2.380, p < 0.001) and PDR (OR = 1.605, 95% CI = 1.106-2.329, p = 0.013) in younger diagnosed patients was increased after multivariable adjustment.

CONCLUSIONS

Age of onset was an independent risk factor for developing DR and PDR. This suggests that it is urgent to closely monitor and treat the metabolic disorders in younger T2D patients to delay the occurrence and progression of DR.

Prevalence of and Factors Associated with Diabetic Retinopathy in Patients with Diabetes Mellitus at Siriraj Hospital - Thailand's Largest National Tertiary Referral Center

PURPOSE

We aimed to determine the prevalence of and factors associated with diabetic retinopathy (DR) in patients with diabetes mellitus (DM) and to evaluate the relationship between significant factors and severity of DR.

PATIENTS AND METHODS

A retrospective cross-sectional study of 1130 diabetic patients (mean age: 60 years, 62.7% female, 91% type 2 diabetes) was conducted in the diabetes clinic of Siriraj Hospital (Bangkok, Thailand) during January 2012 to June 2015. DR was graded as absent, mild, moderate, or severe non-proliferative DR, or proliferative DR. Multivariate logistic regression analysis was used to identify independent risk factors for DR in DM patients.

RESULTS

The overall prevalence of DR was 34.78%. Multivariate analysis revealed duration of diabetes, glycated hemoglobin level (HbA_1c), presence of albuminuria, and abnormal protective sensation to be independent risk factors for DR. The prevalence of DR increased with longer duration of diabetes (p < 0.001), deterioration of glucose control (p = 0.006 for HbA_1c), presence of significant albuminuria (p = 0.010), and loss of protective sensation (p = 0.001).

CONCLUSION

In this study, one-third of DM were found to have DR. The independent predictors of DR were duration of diabetes, HbA_1c level, presence of significant albuminuria, and impaired protective sensation. Heightened awareness of these risk factors will decrease the prevalence and severity of DR, and will improve early diagnosis and treatment of DR.

Reduced minimum rim width of optic nerve head: a potential early marker of retinal neurodegeneration in children and adolescents with type 1 diabetes

AIMS

To determine whether early retinal neurodegenerative changes in pediatric patients with type 1 diabetes (T1D) can be detected by spectral domain-optical coherence tomography (SD-OCT) and whether such changes are associated with risk factors for T1D complications.

METHODS

A total of 147 T1D children/adolescents and 51 healthy controls underwent SD-OCT. Spherical refractive error (SRE), macular total retinal thickness (TRT), ganglion cell layer (GCL), retinal nerve fiber layer (RNFL), minimum rim width (MRW), and Bruch's membrane opening area (BMOA) were measured. Clinical and biochemical parameters were recorded at the time of SD-OCT and starting at T1D onset. Multiple regression models were calculated using SD-OCT parameters as dependent and risk factors as independent variables.

RESULTS

MRW was significantly thinner in the T1D patients (global MRW:361.58vs386.33 µm; p = 0.009), while RNFL and macular parameters were similar for both groups. MRW was inversely correlated with mean HbA1c (r ≥ -0.180, p < 0.05). Multiple regression showed that part of the variability in MRW was explained by HbA1c and BMOA (R² = 0.21; p < 0.001), independent of other cardiometabolic risk factors.

CONCLUSIONS

MRW reduction could be a potential early marker of retinal neurodegeneration detectable in pediatric patients with T1D. The association between MRW and mean HbA1c suggests that glucometabolic control may affect early retinal neurodegeneration starting in childhood.

NMR-based metabolomics characterizes metabolic changes in different brain regions of streptozotocin-induced diabetic mice with cognitive decline

Diabetes at advanced age increases rise of cognitive impairment, but its potential mechanisms are still far from being fully understood. In this study, we analyzed the metabolic alterations in six different brain regions between streptozotocin (STZ)-induced diabetic mice with cognitive decline (DM) and age-matched controls (CON) using a ¹H NMR-based metabolomics approach, to explore potential metabolic mechanisms underlying diabetes-induced cognitive decline. The results show that DM mice had a peculiar metabolic phenotype in all brain regions, mainly involving increased lactate level, decreased choline and energy metabolism as well as disrupted astrocyte-neuron metabolism. Furthermore, these metabolic changes exhibited a brain region-specific pattern. Collectively, our results suggest that brain region-specific metabolic disorders may be responsible for diabetes-induced cognitive dysfunction.

Bacterial infections as novel risk factors of severe diabetic retinopathy in individuals with type 1 diabetes

Background/Aims

Diabetic retinopathy (DR) is associated and shares many risk factors with other diabetic complications, including inflammation. Bacterial infections, potent inducers of inflammation have been associated with the development of diabetic complications apart from DR. Our aim was to investigate the association between bacterial infections and DR.

Methods

Adult individuals with type 1 diabetes (n=1043) were recruited from the Finnish Diabetic Nephropathy Study (FinnDiane), a prospective follow-up study. DR was defined as incident severe diabetic retinopathy (SDR), identified as first laser treatment. Data on DR were obtained through fundus photographs and medical records, data on bacterial infections from comprehensive national registries (1 January 1995 to 31 December 2015). Risk factors for DR and serum bacterial lipopolysaccharide (LPS) activity were determined at baseline.

Results

Individuals with incident SDR (n=413) had a higher mean number of antibiotic purchases/follow-up year compared with individuals without incident SDR (n=630) (0.92 [95% CI 0.82 to 1.02] vs 0.67 [0.62–0.73], p=0.02), as well as higher levels of LPS activity (0.61 [0.58–0.65] vs 0.56 [0.54–0.59] EU/mL, p=0.03). Individuals with on average ≥1 purchase per follow-up year (n=269) had 1.5 times higher cumulative incidence of SDR, compared with individuals with <1 purchase (n=774) per follow-up year (52% vs 35%, p<0.001). In multivariable Cox survival models, the mean number of antibiotic purchases per follow-up year as well as LPS activity were risk factors for SDR after adjusting for static confounders (HR 1.16 [1.05–1.27], p=0.002 and HR 2.77 [1.92–3.99], p<0.001, respectively).

Conclusion

Bacterial infections are associated with an increased risk of incident SDR in type 1 diabetes.

Enteroviruses and T1D: Is It the Virus, the Genes or Both which Cause T1D

Type 1 diabetes (T1D) is a chronic autoimmune disorder that results from the selective destruction of insulin-producing β-cells in the pancreas. Up to now, the mechanisms triggering the initiation and progression of the disease are, in their complexity, not fully understood and imply the disruption of several tolerance networks. Viral infection is one of the environmental factors triggering diabetes, which is initially based on the observation that the disease’s incidence follows a periodic pattern within the population. Moreover, the strong correlation of genetic susceptibility is a prerequisite for enteroviral infection associated islet autoimmunity. Epidemiological data and clinical findings indicate enteroviral infections, mainly of the coxsackie B virus family, as potential pathogenic mechanisms to trigger the autoimmune reaction towards β-cells, resulting in the boost of inflammation following β-cell destruction and the onset of T1D. This review discusses previously identified virus-associated genetics and pathways of β-cell destruction. Is it the virus itself which leads to β-cell destruction and T1D progression? Or is it genetic, so that the virus may activate auto-immunity and β-cell destruction only in genetically predisposed individuals?

Vascular Complication in Adolescents With Diabetes Mellitus

Diabetes mellitus is becoming more prevalent and even with new advancements which improve glycaemic control, complications of diabetes are common. Vascular complications of diabetes include the microvascular complications: retinopathy, nephropathy, and peripheral and autonomic neuropathy. Macrovascular complications are also common in patients with diabetes and arguably more concerning as they confer a high mortality risk yet are sometimes under-treated. Risk factors for diabetes complications start to occur in childhood and adolescents and some youths may be diagnosed with complications before transition to adult care. This article discusses the prevalence, risk factors, screening, and treatment recommendations for vascular complications in children and adolescents with diabetes.

Increased Plasma Soluble Interleukin-2 Receptor Alpha Levels in Patients With Long-Term Type 1 Diabetes With Vascular Complications Associated With IL2RA and PTPN2 Gene Polymorphisms

Type 1 diabetes (T1D) is largely considered an autoimmune disease leading to the destruction of insulin-producing pancreatic β cells. Further, patients with T1D have 3-4-fold increased risk of developing micro- and macrovascular complications. However, the contribution of immune-related factors contributing to these diabetes complications are poorly understood. Individuals with long-term T1D who do not progress to vascular complications offer a great potential to evaluate end-organ protection. The aim of the present study was to investigate the association of inflammatory protein levels with vascular complications (retinopathy, nephropathy, cardiovascular disease) in individuals with long-term T1D compared to individuals who rapidly progressed to complications. We studied a panel of inflammatory markers in plasma of patients with long-term T1D with (n = 81 and 26) and without (n = 313 and 25) vascular complications from two cross-sectional Scandinavian cohorts (PROLONG and DIALONG) using Luminex technology. A subset of PROLONG individuals (n = 61) was screened for circulating immune cells using multicolor flow cytometry. We found that elevated plasma levels of soluble interleukin-2 receptor alpha (sIL-2R) were positively associated with the complication phenotype. Risk carriers of polymorphisms in the IL2RA and PTPN2 gene region had elevated plasma levels of sIL-2R. In addition, cell surface marker analysis revealed a shift from naïve to effector T cells in T1D individuals with vascular complications as compared to those without. In contrast, no difference between the groups was observed either in IL-2R cell surface expression or in regulatory T cell population size. In conclusion, our data indicates that IL2RA and PTPN2 gene variants might increase the risk of developing vascular complications in people with T1D, by affecting sIL-2R plasma levels and potentially lowering T cell responsiveness. Thus, elevated sIL-2R plasma levels may serve as a biomarker in monitoring the risk for developing diabetic complications and thereby improve patient care.

Prophylactic Intravitreal Bevacizumab After Plaque Radiotherapy for Uveal Melanoma: Analysis of Visual Acuity, Tumor Response, and Radiation Complications in 1131 Eyes Based on Patient Age

PURPOSE

The aim of this study was to determine the impact of age on radiation complications after plaque radiotherapy and prophylactic intravitreal bevacizumab for uveal melanoma.

DESIGN

Retrospective cohort study.

METHODS

Retrospective single-center study of plaque-irradiated uveal melanoma with prophylactic intravitreal bevacizumab at 4-month intervals from July 2000 to January 2018.

RESULTS

Of 1131 eyes in 1131 patients, age was <50 years (n = 231), 50 to 70 years (n = 657), or >70 years (n = 243). Comparison by age category (<50 vs 50-70 vs >70 years) revealed the oldest group presenting with greatest tumor basal diameter (11.3 vs 11.3 vs 12.1 mm, P = 0.03) and worst visual acuity (20/40 vs 20/40 vs 20/50, P = 0.02). After plaque (mean follow-up 40 vs 42 vs 32 months, P < 0.001), radiation complications were most common in the youngest age group, including maculopathy (48% vs 39% vs 28%, P < 0.001), extramacular retinopathy (30% vs 25% vs 16%, P = 0.002), and papillopathy (21% vs 18% vs 12%, P = 0.03). The youngest age group had the highest Kaplan-Meier estimated 48-month cumulative probability for radiation maculopathy (62% vs 46% vs 47%, P = 0.001), extramacular retinopathy (36% vs 34% vs 29%, P = 0.03), and papillopathy (29% vs 26% vs 22%, P = 0.13). On subanalysis, the youngest age group had increased 48-month risk of developing radiation maculopathy when compared with the middle [hazard ratio (HR) = 1.5, P = 0.001] and older (HR = 1.6, P = 0.005) age groups and increased 48-month risk of developing extramacular radiation retinopathy compared with the older age group (HR = 1.5, P = 0.04).

CONCLUSIONS

After plaque radiotherapy for uveal melanoma and prophylactic intravitreal bevacizumab at 4-month intervals, patients younger than 50 years old have an increased 48-month risk of radiation maculopathy.

CACNB2 Is a Novel Susceptibility Gene for Diabetic Retinopathy in Type 1 Diabetes

Diabetic retinopathy is a common diabetes complication that threatens the eyesight and may eventually lead to acquired visual impairment or blindness. While a substantial heritability has been reported for proliferative diabetic retinopathy (PDR), only a few genetic risk factors have been identified. Using genome-wide sib pair linkage analysis including 361 individuals with type 1 diabetes, we found suggestive evidence of linkage with PDR at chromosome 10p12 overlapping the CACNB2 gene (logarithm of odds = 2.73). Evidence of association between variants in CACNB2 and PDR was also found in association analysis of 4,005 individuals with type 1 diabetes with an odds ratio of 0.83 and P value of 8.6 × 10^-4 for rs11014284. Sequencing of CACNB2 revealed two coding variants, R476C/rs202152674 and S502L/rs137886839. CACNB2 is abundantly expressed in retinal cells and encodes the β2 subunit of the L-type calcium channel. Blocking vascular endothelial growth factor (VEGF) by intravitreous anti-VEGF injections is a promising clinical therapy to treat PDR. Our data show that L-type calcium channels regulate VEGF expression and secretion from retinal pigment epithelial cells (ARPE19) and support the role of CACNB2 via regulation of VEGF in the pathogenesis of PDR. However, further genetic and functional studies are necessary to consolidate the findings.

Risk factors for prevalent diabetic retinopathy and proliferative diabetic retinopathy in type 1 diabetes

PURPOSE

Age at diagnosis of type 1 diabetes (DM1) has been implied as an important factor associated with the development of the microvascular complications. Our aim was to identify factors associated with prevalent diabetic retinopathy (DR) and proliferative diabetic retinopathy (PDR) in DM1 people with early and late-onset.

METHODS

We reviewed medical records from all DM1 people from the reference area of a tertiary center (about 340,000 persons). Univariate and multivariate logistic regression were used to assess the relationship between potential risk factors (sociodemographic, diabetes-related, co-morbidities, and laboratory parameters) and prevalent DR/PDR. We performed an analysis comparing patients diagnosed before (early-onset) and after (late-onset) 18 years of age.

RESULTS

We included 140 patients in early-onset DM1 group and 169 in late-onset DM1 group. Longer duration of diabetes and HbA1c remained associated with prevalent DR in both groups after adjusting for potential risk factors. Nephropathy was associated with prevalent DR in the late-onset group but not in the early-onset group. Peripheral neuropathy remained associated with prevalent PDR when modeled together in the multivariate model. High BMI demonstrated a significative association with PDR in early but not in the late-onset DM1 group.

CONCLUSIONS

Although previous reports suggest that age at DM1 diagnosis may have a role in DR prevalence, the risk factors for DR in early and late-onset DM1 were similar for both groups. Duration of disease and lifelong metabolic control were the major predictors for DR in both groups. Nephropathy was associated with DR in patients with late-onset disease. Neuropathy was associated with PDR occurrence in both groups. BMI was associated with PDR early-onset DM1 group.

A new strategy for vascular complications in young people with type 1 diabetes mellitus

Diabetes vascular complications, including cardiovascular disease, diabetic nephropathy and retinopathy, have a negative effect on the long-term prognosis of young people with type 1 diabetes mellitus (T1DM). Poor glycaemic control and consequent increased HbA_1c levels are major risk factors for the development of vascular complications. HbA_1c levels are the main focus of current management strategies; however, the recommended target is rarely achieved in adolescents. Thus, a clear need exists for improved biomarkers to identify high-risk young people early and to develop new intervention strategies. Evidence is accumulating that early increases in urinary albumin excretion could be predictive of adolescents with T1DM who are at an increased risk of developing vascular complications, independent of HbA_1c levels. These findings present an opportunity to move towards the personalized care of adolescents with T1DM, which takes into consideration changes in albumin excretion and other risk factors in addition to HbA_1c levels.

Impact of Age of Onset, Puberty, and Glycemic Control Followed From Diagnosis on Incidence of Retinopathy in Type 1 Diabetes: The VISS Study

OBJECTIVE

To evaluate sex, age at diabetes onset, puberty, and HbA_1c, with subjects followed from diabetes diagnosis and during different time periods, as risk factors for developing diabetic simplex and proliferative retinopathy.

RESEARCH DESIGN AND METHODS

In a population-based observational study, HbA_1c for 451 patients diagnosed with diabetes before 35 years of age during 1983-1987 in southeast Sweden was followed for up to 18-24 years from diagnosis. Long-term mean weighted HbA_1c (wHbA_1c) was calculated. Retinopathy was evaluated by fundus photography and analyzed in relation to wHbA_1c levels.

RESULTS

Lower wHbA_1c, diabetes onset ≤5 years of age, and diabetes onset before puberty, but not sex, were associated with longer time to appearance of simplex retinopathy. Proliferative retinopathy was associated only with wHbA_1c. The time to first appearance of any retinopathy decreased with increasing wHbA_1c. Lower wHbA_1c after ≤5 years' diabetes duration was associated with later onset of simplex retinopathy but not proliferative retinopathy. With time, most patients developed simplex retinopathy, except for those of the category wHbA_1c ≤50 mmol/mol (6.7%), for which 20 of 36 patients were without any retinopathy at the end of the follow-up in contrast to none of 49 with wHbA_1c >80 mmol/mol (9.5%).

CONCLUSIONS

Onset at ≤5 years of age and lower wHbA_1c the first 5 years after diagnosis are associated with longer duration before development of simplex retinopathy. There is a strong positive association between long-term mean HbA_1c measured from diagnosis and up to 20 years and appearance of both simplex and proliferative retinopathy.

A multicentre study evaluating the risk and prevalence of diabetic retinopathy in children and young people with type 1 diabetes mellitus

INTRODUCTION

There is currently limited data published on the prognostic factors and prevalence of diabetic eye disease in children and young people (CYP) with Type 1 diabetes mellitus (T1DM), yet diabetic retinopathy remains one of the commonest causes of blindness in young adults. The aim of this study was to determine the risk and prevalence of diabetic retinopathy (DR) and to evaluate the risk factors associated with diabetic retinopathy in CYP with T1DM.

METHODS

All CYP with Type 1 diabetes between 12 and 18 years of age, registered with the regional diabetic retinopathy screening programme were evaluated from 2012 to 2013 in four diabetes units within the north west region of the United Kingdom. Patients who had evidence of diabetic retinopathy were reviewed to identify risk factors for presence or absence of diabetic retinopathy.

RESULTS

237 patients between the ages 12-18 years were included in the. The prevalence of diabetic retinopathy was 11%. Out of 27 patients with evidence of diabetic retinopathy, 44% were reported as background changes and 56% had pre-proliferative DR. Significant risk factors for diabetic retinopathy disease in the population using univariate analyses were duration of diabetes, puberty, age at diagnosis and mean HbA1c in the preceding 12 months. Multivariate logistic regression analysis found age of diagnosis (p = 0.04) and mean HbA1c as significant independent risk factors for presence of diabetic retinopathy (p = 0.02).

CONCLUSIONS

The prevalence of diabetic retinopathy in this paediatric population was 11%. Early age at diagnosis and poor metabolic control are independent risk factors for diabetic retinopathy.

Management of diabetes complications in youth

Type 1 and type 2 diabetes are increasing in prevalence and diabetes complications are common. Diabetes complications are rarely studied in youth, despite the potential onset in childhood. Microvascular complications of diabetes include retinopathy, diabetic kidney disease or nephropathy, and neuropathy that may be somatic or autonomic. Macrovascular disease is the leading cause of death in patients with type 1 diabetes. Strict glycaemic control will reduce microvascular and macrovascular complications; however, they may still manifest in youth. This article discusses the diagnosis and treatment of complications that arise from type 1 and type 2 diabetes mellitus in youth. Screening for complications is paramount as early intervention improves outcome. Screening should commence from 11 years of age depending on the duration of type 1 diabetes or at diagnosis for patients with type 2 diabetes. Diabetic retinopathy may require invasive treatment such as laser therapy or intravitreal antivascular endothelial growth factor therapy to prevent future blindness. Hypertension and albuminuria may herald diabetic nephropathy and require management with angiotensin converting enzyme (ACE) inhibition. In addition to hypertension, dyslipidaemia must be treated to reduce macrovascular complications. Interventional trials aimed at examining the treatment of diabetes complications in youth are few. Statins, ACE inhibitors and metformin have been successfully trialled in adolescents with type 1 diabetes with positive effects on lipid profile, microalbuminuria and measures of vascular health. Although relatively rare, complications do occur in youth and further research into effective treatment for diabetes complications, particularly therapeutics in children in addition to prevention strategies is required.

Nomogram for prediction of non-proliferative diabetic retinopathy in juvenile-onset type 1 diabetes: a cohort study in an Asian population

The need for screening for retinopathy in patients with type 1 diabetes mellitus (T1DM) has been emphasised, but diagnostic delays were reported when screening was done at fixed intervals. To establish an individualised risk-prediction model to assist screening non-proliferative diabetic retinopathy (NPDR) in T1DM, we performed a retrospective cohort study enrolling participants in the Chang Gung Juvenile Diabetes Eye Study. There were 413 patients with 12 381 records analysed from 2005 to 2015. A time-dependent Cox proportional hazard analysis was used to evaluate the risks of NPDR development and a nomogram with risk-stratification indicators was established based on the results. During 97 months of follow-up, 43 of 413 patients (10.4%) developed NPDR. Male sex (HR: 0.4, 95% CI: 0.19–0.85), age 5–14 years at onset of T1DM (6.38, 2.41–16.87), duration of diabetes (1.57, 1.41–1.75), and hemoglobin A1c level (1.56, 1.35–1.80) were independently associated with NPDR. Using the nomogram offers a quick method in the clinical setting to interpret the risk of NPDR development. Based on its weighting, each of the independent factors is allocated a score, and the total points indicate the probabilities of NPDR occurring within 6 months, 1 year, and 3 years.

Incidence of diabetes retinopathy and determinants of time to diabetes retinopathy among diabetes patients at Tikur Anbessa Hospital, Ethiopia: a retrospective follow up study

OBJECTIVE

Data regarding diabetes retinopathy and associated factors are currently lacking in Ethiopia. The study aims to determine the incidence and determinants of time to diabetes retinopathy among diabetes mellitus patients at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia.

RESULTS

The incidence of diabetes retinopathy is a rapidly growing burden of disease in Ethiopia. The incidence rate of diabetes retinopathy was 2.65 (95% CI 2. 54, 4.05) per 1000 person-years observation. Moreover, 70 (18.57%, 95% CI 14.63, 22.5) DM patients developed diabetes retinopathy. The median time was 74.07 months (with IQR 53.60, 89.88). Male sex (AHR = 1.94, 95% CI = 1.10, 3.39), type 2 DM (AHR = 4.01, 95% CI = 1.34, 12.00), creatinine (AHR = 2.59, 95% CI = 1.91, 3.52), borderline triglyceride (AHR = 2.87, 95% CI 1.33, 6.21) and high triglyceride levels (AHR = 2.59, 95% CI = 1.31, 4.97) were positively correlated factors to diabetes retinopathy occurrence. Multisectoral, population-based approaches are needed to reduce type 2 DM complications.

Metabolomics Analysis of Human Vitreous in Diabetic Retinopathy and Rhegmatogenous Retinal Detachment

The vitreous humor is a highly aqueous eye fluid interfacing with the retina and lens and providing shape. Its molecular composition provides a readout for the eye's physiological status. Changes in cellular metabolism underlie vitreoretinal pathologies, but despite routine surgical collection of vitreous, only limited reports of metabolism in the vitreous of human patients have been described. Vitreous samples from patients with rhegmatogenous retinal detachment ( n = 25) and proliferative diabetic retinopathy ( n = 9) were profiled along with control human vitreous samples ( n = 8) by untargeted mass-spectrometry-based metabolomics. Profound changes were observed in diabetic retinopathy vitreous, including altered glucose metabolism and activation of the pentose phosphate pathway, which provides reducing equivalents to counter oxidative stress. In addition, purine metabolism was altered in diabetic retinopathy, with decreased xanthine and elevated levels of related purines (inosine, hypoxanthine, urate, allantoate) generated in oxidant-producing reactions. In contrast, the vitreous metabolite profiles of retinal detachment patients were similar to controls. In total, our results suggest a rewiring of vitreous metabolism in diabetic retinopathy that underlies disease features such as oxidative stress and furthermore illustrates how the vitreous metabolic profile may be impacted by disease.