The prevalence of retinopathy in prediabetes: A systematic review

Clinical practice recommendations for management of Diabetes Mellitus in Arab region: An expert consensus statement from Arab Diabetes Forum (ADF)

Prevalence of diabetes in Arab region has significantly increased, resulting in a significant economic burden on healthcare systems. This surge can be attributed to obesity, rapid urbanization, changing dietary habits, and sedentary lifestyles. The Arab Diabetes Forum (ADF) has established localized recommendations to tackle the region's rising diabetes prevalence. The recommendations, which incorporate worldwide best practices, seek to enhance the quality of treatment for people with diabetes by raising knowledge and adherence among healthcare providers. The guidelines include comprehensive recommendations for screening, diagnosing, and treating type 1 and type 2 diabetes in children and adults for better overall health results.

Can the postload-fasting glucose gap be used to determine risk of developing diabetes in chinese adults: A prospective cohort study

OBJECTIVE

To evaluate the relationship between fasting plasma glucose (FPG) and 2-hour postload plasma glucose (2hPG) measured during an oral glucose tolerance test, and the risk of developing diabetes in Chinese adults.

METHODS

We followed 3,094 participants without diabetes, categorizing them based on their oral glucose tolerance test (OGTT) results into low post load (2hPG ≤ FPG) and high post load (2hPG > FPG) at baseline. We monitored the incidence of diabetes, incidence of prediabetes, disease progression from prediabetes to diabetes and disease reversal from prediabetes to normal glucose tolerance (NGT) over an average of 3.2 years of follow-up. After the Schoenfeld residual test, Cox's time-varying covariate (Cox-TVC) models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) to compare the different clinical events between low and high post load groups.

RESULTS

In the cohort study, of the 3,094 participants, 702 (22.7 %) had low post load (2hPG ≤ FPG, mean postload-fasting gap: -0.8 ± 0.7 mmol/L) and 2,392 (77.3 %) had high post load (2hPG > FPG, mean postload-fasting gap: 1.8 ± 1.2 mmol/L). Over 3.2 ± 0.2 years of follow-up, 282 (9.1 %) developed diabetes. In the low post load group, the incidence rates per 1,000 person-years were: diabetes was 7.9, prediabetes was 70.0, disease progression from prediabetes to diabetes was 23.4 and disease reversal to NGT was 327.2. For the high post load group, incidence rates for diabetes was 13.9, prediabetes was 124.3, disease progression was 59.5 and disease reversal was 238.6 per 1,000 person-years. Participants with high post load showed higher incidence rates of diabetes, prediabetes, and progression from prediabetes to diabetes compared to those with low post load. HRs were significantly higher for incident diabetes and prediabetes, and disease progression from prediabetes to diabetes, whereas disease reversal was lower.

CONCLUSION

The risk of developing prediabetes/diabetes after 3.2 years of follow-up was higher in the participants with high post load. It suggested that postload-fasting gap may be a simple tool to predict the risk of developing prediabetes, diabetes or reversal to NGT.

Efficacy and safety of glucagon-like peptide-1 receptor agonists on prediabetes: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Prediabetes is a condition preceding the development of diabetes and is associated with an increased risk of a number of complications. The primary mode of management is thought to be lifestyle modification. Pharmacological therapy, such as glucagon-like peptide-1 receptor agonists (GLP-1RAs), were not well addressed in the literature and were only evaluated in trials as secondary and exploratory outcomes with a limited sample size. Here, GLP-1RAs are evaluated as a comprehensive therapy approach for patients with prediabetes.

METHODS

A comprehensive search of Web of Science, SCOPUS, PubMed, and Cochrane was performed on May 5, 2023, to retrieve randomized controlled trials (RCTs) comparing the effect of GLP-1RAs to placebo and/or lifestyle modification on prediabetes reversion to normoglycemia, prevention of overt diabetes, glycemic control, anthropometric parameters, and lipid profiles. Review Manager (RevMan) version 5.4 was used. The quality of RCTs was assessed using the revised version of the Cochrane Risk of Bias Tool. GRADE was performed to evaluate the certainty of evidence.

RESULTS

Twelve trials involving 2903 patients in the GLP-1RAs group and 1413 in the control group were included in the meta-analysis. Low quality of evidence revealed that GLP-1RAs significantly increased the incidence of prediabetes reversion to the normoglycemic state [RR = 1.76, 95% CI (1.45, 2.13), P < 0.00001] and moderate quality of evidence showed that GLP-1RAs significantly prevented new-onset diabetes [RR = 0.28, 95% CI (0.19, 0.43), P < 0.00001]. Significant reductions in HbA1c, fasting plasma glucose, body weight, waist circumference, triglycerides, and LDL were observed in the GLP-1RAs arm (P < 0.05). However, higher incidences of gastrointestinal disorders were reported in the GLP-1RAs group (P < 0.05).

CONCLUSIONS

GLP-1RAs combined with lifestyle modification proved to be a more effective therapy for managing prediabetic patients than lifestyle modification alone, with a tolerable safety profile. Future guidelines should consider GLP-1RAs as an adjunct to lifestyle modification in the management of prediabetic patients to provide better management and improve treatment adherence.

Comparative efficacy and acceptability of different exercise patterns for reducing cardiovascular events in pre-diabetes: protocol for a systematic review and network meta-analysis of randomised controlled trials

INTRODUCTION

Exercise has been used to reverse dysglycaemic states in patients with pre-diabetes. Systematic reviews show that exercise is an effective way to reduce the incidence of diabetes, but there is conflicting evidence for reducing the occurrence of cardiovascular events. Therefore, we present a systematic review and network meta-analysis protocol designed to compare the effectiveness of different forms of exercise in reducing cardiovascular events and their tolerability in different populations.

METHODS AND ANALYSIS

We will include all randomised controlled trials and compare one exercise intervention to another. We will compare the following exercise patterns: standard endurance training, strength training, high-intensity interval training, mind-body exercise, and mixed strength and aerobic training. The primary outcomes are the occurrence of major cardiovascular events and the rate of patient attrition during the intervention. We will search major English and Chinese databases as well as trial registry websites for published and unpublished studies. All reference selection and data extraction will be conducted by at least two independent reviewers. We will conduct a random effects model to combine effect sizes and use the surface under the cumulative ranking curve and the mean ranks to rank the effectiveness of interventions. All data will be fitted at WinBUGS in a Bayesian framework and correlation graphs will be plotted using StataSE 14. We will also use the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework to evaluate the quality of evidence for the study results.

ETHICS AND DISSEMINATION

This study does not involve a population-based intervention, and therefore, does not require ethical approval. We will publish the findings of this systematic review in a peer-reviewed scientific journal, and the dataset will be made available free of charge. The completed review will be disseminated electronically in print and on social media, where appropriate.

PROSPERO REGISTRATION NUMBER

CRD42023422737.

Pros and cons of live kidney donation in prediabetics: A critical review and way forward

There is shortage of organs, including kidneys, worldwide. Along with deceased kidney transplantation, there is a significant rise in live kidney donation. The prevalence of prediabetes (PD), including impaired fasting glucose and impaired glucose tolerance, is on the rise across the globe. Transplant teams frequently come across prediabetic kidney donors for evaluation. Prediabetics are at risk of diabetes, chronic kidney disease, cardiovascular events, stroke, neuropathy, retinopathy, dementia, depression and nonalcoholic liver disease along with increased risk of all-cause mortality. Unfortunately, most of the studies done in prediabetic kidney donors are retrospective in nature and have a short follow up period. There is lack of prospective long-term studies to know about the real risk of complications after donation. Furthermore, there are variations in recommendations from various guidelines across the globe for donations in prediabetics, leading to more confusion among clinicians. This increases the responsibility of transplant teams to take appropriate decisions in the best interest of both donors and recipients. This review focuses on pathophysiological changes of PD in kidneys, potential complications of PD, other risk factors for development of type 2 diabetes, a review of guidelines for kidney donation, the potential role of diabetes risk score and calculator in kidney donors and the way forward for the evaluation and selection of prediabetic kidney donors.

Relationship between circulating metabolites and diabetic retinopathy: a two-sample Mendelian randomization analysis

Diabetic retinopathy (DR) is the most frequent microvascular complication of diabetes mellitus, however, its underlying biological mechanisms remain poorly understood. We examined single nucleotide polymorphisms linked to 486 blood metabolites through extensive genome-wide association studies conducted on individuals of European ancestry. The FinnGen Biobank database served as a reference to define DR. Two-sample MR analysis was conducted to reveal the association between the levels of genetically predicted circulating metabolites and the susceptibility to DR. To validate the robustness of the obtained findings, sensitivity analyses with weighted median, weighted mode, and MR-Egger were conducted. 1-oleoylglycerophosphoethanolamine (odds ratio [OR] (OR per one standard deviation [SD] increase) = 0.414; 95% confidence interval [CI] 0.292-0.587; P = 7.613E-07, PFDR = 6.849E-06), pyroglutamine (OR per one SD increase = 0.414; 95% confidence interval [CI] 0.292-0.587; P = 8.31E-04, PFDR = 0.007), phenyllactate (PLA) (OR per one SD increase = 0.591; 95% confidence interval [CI] 0.418-0.836; P = 0.003, PFDR = 0.026), metoprolol acid metabolite (OR per one SD increase = 0.978; 95% confidence interval [CI] 0.962-0.993; P = 0.005, PFDR = 0.042), 10-undecenoate (OR per one SD increase = 0.788; 95% confidence interval [CI] 0.667-0.932; P = 0.005, PFDR = 0.049), erythritol (OR per one SD increase = 0.691; 95% confidence interval [CI] 0.513-0.932; P = 0.015, PFDR = 0.034), 1-stearoylglycerophosphoethanolamine (OR per one SD increase = 0.636; 95% confidence interval [CI] 0.431-0.937; P = 0.022, PFDR = 0.099), 1-arachidonoylglycerophosphoethanolamine (OR per one SD increase = 0.636; 95% confidence interval [CI] 0.431-0.937; P = 0.030, PFDR = 0.099) showed a significant causal relationship with DR and could have protective effects. stachydrine (OR per one SD increase = 1.146; 95% confidence interval [CI] 1.066-1.233; P = 2.270E-04, PFDR = 0.002), butyrylcarnitine (OR per one SD increase = 1.117; 95% confidence interval [CI] 1.023-1.219; P = 0.014, PFDR = 0.062), 5-oxoproline (OR per one SD increase = 1.569; 95% confidence interval [CI] 1.056-2.335; P = 0.026, PFDR = 0.082), and kynurenine (OR = 1.623; 95% CI 1.042-2.526; P = 0.041, PFDR = 0.097) were significantly associated with an increased risk of DR. This study identified metabolites have the potential to be considered prospective compounds for investigating the underlying mechanisms of DR and for selecting appropriate drug targets.

Optical Coherence Tomography Angiography as a Diagnostic Tool for Diabetic Retinopathy

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes mellitus, leading to visual impairment if left untreated. This review discusses the use of optical coherence tomography angiography (OCTA) as a diagnostic tool for the early detection and management of DR. OCTA is a fast, non-invasive, non-contact test that enables the detailed visualisation of the macular microvasculature in different plexuses. OCTA offers several advantages over fundus fluorescein angiography (FFA), notably offering quantitative data. OCTA is not without limitations, including the requirement for careful interpretation of artefacts and the limited region of interest that can be captured currently. We explore how OCTA has been instrumental in detecting early microvascular changes that precede clinical signs of DR. We also discuss the application of OCTA in the diagnosis and management of various stages of DR, including non-proliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR), diabetic macular oedema (DMO), diabetic macular ischaemia (DMI), and pre-diabetes. Finally, we discuss the future role of OCTA and how it may be used to enhance the clinical outcomes of DR.

Red Cell Distribution Width and Prediabetes in Adults in Northern Sudan: A Case-Control Study

Diabetes mellitus (DM) is a major public health issue worldwide. Red cell distribution width (RDW) has been reported to have predictive value in several diseases, including DM. Few data exist on the association between RDW and the prediabetic stage. Thus, the present study aimed to investigate the association between RDW and prediabetes in adults in Sudan. This case-control study was conducted in Northern Sudan in 2022. The cases (n = 107) were prediabetic patients categorized according to the level of glycated hemoglobin (HbA1c), which ranged from 5.7% to 6.4%, while the controls (n = 107) were healthy participants. A questionnaire was used to collect the data. Standard methods were used to measure the HbAIc level and RDW. Logistic regression analysis was performed. The median (interquartile range (IQR)) of the RDW was significantly higher in prediabetic patients than in the controls (14.5% [13.8-15.3%] vs. 14.1% [13.6-14.7%], p = 0.003). Sex, educational level, occupational status, marital status, cigarette smoking, alcohol consumption, family history of DM, and body mass index were not associated with prediabetes. In the multivariate-adjusted model, higher age and higher RDW were associated with prediabetes. A positive correlation was found between RDW and HbA1c levels (r = 0.19, p = 0.006). In conclusion, this study supports the use of RDW as a predictor of DM.

Use of digital retinography to detect vascular changes in pre-diabetic patients: a cross-sectional study

BACKGROUND

Diabetic retinopathy (DR) is a common complication of DM and may go unnoticed until irreversible damage occurs. Its screening can contribute to the early detection. Although, there are no studies which investigate the ability of digital retinography to detect vascular changes in pre-diabetic patients.

OBJECTIVE

Identify the prevalence and severity of RD in patients with pre-diabetes.

METHODS

Cross-sectionalstudy carried out in a sample of patients with pre-diabetes and weight excess characterized from January 2020 to April 2023. Sociodemographic and clinical variables were collected, in addition to lifestyle habits. Retinographic evaluation was also performed using a Digital Retinography. For the analysis of all variables, the adopted significance level was 5%. The software used for the analysis was SPSS version 25.0.

RESULTS

Of 108 patients selected 7.1% have alteration in the exam indicating DR. Among the participants with diabetic retinopathy, four had the moderate form (50%), three the moderate form (37%) and only one participant had the severe form (13%).

CONCLUSIONS

Our findings highlight the importance of preventive measures and adequate control of these conditions in pre-diabetic patients, in order to prevent or delay the progression of diabetic retinopathy and, consequently, reduce the risk of blindness and other ocular complications.

Prevalence of Retinopathy in Prediabetic Populations: A Systematic Review and Meta-Analysis

Among the leading causes of vision impairment and blindness globally, diabetic retinopathy (DR) is one of the most important causes. There is increasing evidence of DR prevalence in the prediabetic population. This systematic review presents collective data on retinopathy in the prediabetic population. This review article aimed to estimate the reported prevalence of retinopathy in prediabetes, impaired glucose tolerance test (GTT) without diabetes mellitus, and the risk factors involved and to summarize it. Literature searches were done using the Web of Science, CINAHL, Google Scholar, Cochrane, EMBASE, and PubMed databases from inception to April 2023. Our search included the words prediabetes, DR, and risk factors. All searches were looked at for methodological quality and evidence. Thirty-one studies were included after the screening. Population-based data were used in 23 studies (82.1%). The prediabetic population screened was 10,539. The prevalence of retinopathy ranged between 0.3% and 20.9%, showing a median of 8.1% with an interquartile range (IQR) of 4.2-11%, showing great variance in estimates due to the use of different screening methods, methods used for retinopathy grading, and study populations. Several studies compared the population with normal GTT with impaired glucose tolerance (IGT) and inferred that there was a lower prevalence of retinopathy in the normal GTT population (3.0%, IQR 0.3-7.4%) than prediabetes (6.7%, IQR 1.9-10.1%). According to this data, a greater retinopathy prevalence was found in prediabetic populations.

Cardiovascular and microvascular outcomes according to vitamin D level and genetic variants among individuals with prediabetes: a prospective study

BACKGROUND

Whether serum vitamin D mediate vascular diseases in prediabetic populations remains unclear. This study aimed to determine the associations between circulating 25-hydroxyvitamin D [25(OH)D] levels and vitamin D receptor (VDR) polymorphisms with the risk of macrovascular complications, including myocardial infarction and stroke, and microvascular complications such as diabetic nephropathy and retinopathy, among adults with prediabetes.

METHODS

Participants with prediabetes in UK Biobank were included (N = 56,387). Multivariable dose-response and Cox proportion models were used to explore the relationship of serum 25(OH)D status and the risks of vascular complications. The interaction of VDR polymorphisms with serum 25(OH)D level on risks of vascular events was also assessed.

RESULTS

During a median follow-up of 12 years, higher levels of 25(OH)D were significantly and nonlinearly associated with a lower risk of macrovascular diseases among prediabetic individuals. The adjusted hazard ratios (95% confidential interval) of serum 25(OH)D levels of ≥ 75.0 nmol/L versus < 25 nmol/L were 0.75 (0.63-0.88) for myocardial infarction, 0.74 (0.55-1.00) for stroke, 1.02 (0.60-1.74) for diabetic nephropathy, and 1.30 (0.92-1.84) for diabetic retinopathy, respectively. The rs2228570 (FokI) polymorphisms significantly interacted with 25(OH)D on incident myocardial infarction (P-interaction = 0.042) and stroke (P-interaction = 0.033). The individuals with serum 25(OH)D level of 50.0-74.9 nmol/L and rs2228570 (FokI) homozygotes had the lowest risks of vascular complications.

CONCLUSIONS

Lower serum 25(OH)D levels are significantly and nonlinearly associated with an increased risk of cardiocerebrovascular diseases in prediabetic individuals, with VDR polymorphisms of rs2228570 (FokI) modify such associations. Monitoring a safe 25(OH)D concentration is suggested to prevent the vascular complications for prediabetes.

Identification of biomarkers associated with immune scores in diabetic retinopathy

Background

Diabetic retinopathy (DR) causes irreversible visual impairment in diabetes mellitus (DM) patients. Immunity played a crucial role in DR. Nevertheless, the triggering mechanism of DR was not yet thorough enough. Herein, we aim to identify the immune-associated genes as biomarkers associated with immune scores that can distinguish early DR from DM without DR.

Methods

In this study, total RNA of peripheral blood mononuclear cell (PBMC) samples from 15 non-proliferative DR patients and 15 DM patients without DR were collected and the transcriptome sequencing data were extracted. Firstly, the target genes were obtained by intersecting the differentially expressed genes (DEGs), which were screened by "limma", and the module genes (related to immune scores), which were screened by "WGCNA". In order to screen for the crucial genes, three machine learning algorithms were implemented, and a receiver operating characteristic (ROC) curve was used to obtain the diagnostic genes. Moreover, the gene set enrichment analysis (GSEA) was performed to understand the function of diagnostic genes, and analysis of the proportions of immune cells and their association with diagnostic genes was performed to analyze the pathogenesis of DR. Furthermore, the regulatory network of TF-mRNA-miRNA was built to reveal the possible regulation of diagnostic genes. Finally, the quantitative real-time polymerase chain reaction (qRT-PCR) was performed to verify the mRNA level of diagnostic genes.

Results

A total of three immune-associated diagnostic genes, namely, FAM209B, POM121L1P, and PTGES, were obtained, and their expression was increased in PBMC samples of DR, and qRT-PCR results confirmed these results. Moreover, the functions of these genes were associated with immune response. The expression of POM121L1P and PTGES was significantly negatively associated with naive B cells, and the expression of FAM209B was significantly negatively associated with immature dendritic cells. Moreover, ESR1 could regulate both FAM209B and PTGES.

Conclusion

This study identified three immune-associated diagnostic genes, FAM209B, POM121L1P, and PTGES, as biomarkers associated with immune scores in DR for the first time. This finding might proffer a novel perspective of the triggering mechanism of DR, and help to understand the role of immune-associated genes in the molecular mechanism of DR more deeply.

Untargeted Multiomics Approach Coupling Lipidomics and Metabolomics Profiling Reveals New Insights in Diabetic Retinopathy

Diabetic retinopathy (DR) is a microvascular complication of diabetes mellitus (DM) which is the main cause of vision loss in the working-age population. Currently known risk factors such as age, disease duration, and hemoglobin A1c lack sufficient efficiency to distinguish patients with early stages of DR. A total of 194 plasma samples were collected from patients with type 2 DM and DR (moderate to proliferative (PDR) or control (no or mild DR) matched for age, gender, diabetes duration, HbA1c, and hypertension. Untargeted lipidomic and metabolomic approaches were performed. Partial-least square methods were used to analyze the datasets. Levels of 69 metabolites and 85 lipid species were found to be significantly different in the plasma of DR patients versus controls. Metabolite set enrichment analysis indicated that pathways such as metabolism of branched-chain amino acids (methylglutaryl carnitine p = 0.004), the kynurenine pathway (tryptophan p < 0.001), and microbiota metabolism (p-Cresol sulfate p = 0.004) were among the most enriched deregulated pathways in the DR group. Moreover, Glucose-6-phosphate (p = 0.001) and N-methyl-glutamate (p < 0.001) were upregulated in DR. Subgroup analyses identified a specific signature associated with PDR, macular oedema, and DR associated with chronic kidney disease. Phosphatidylcholines (PCs) were dysregulated, with an increase of alkyl-PCs (PC O-42:5 p < 0.001) in DR, while non-ether PCs (PC 14:0-16:1, p < 0.001; PC 18:2-14:0, p < 0.001) were decreased in the DR group. Through an unbiased multiomics approach, we identified metabolites and lipid species that interestingly discriminate patients with or without DR. These features could be a research basis to identify new potential plasma biomarkers to promote 3P medicine.

Diabetic Retinopathy among Patients with Prediabetes Attending the Outpatient Department of Ophthalmology in a Tertiary Eye Care Centre: A Descriptive Cross-sectional Study

INTRODUCTION

Diabetic retinopathy is a specific microvascular ocular complication associated with diabetes. However, retinopathy has also been reported in people with prediabetes. The study aimed to find out the prevalence of diabetic retinopathy among patients with prediabetes attending the outpatient Department of Ophthalmology in a tertiary eye care centre.

METHODS

A descriptive cross-sectional study was conducted among patients with prediabetes attending the outpatient Department of Ophthalmology in a tertiary eye care centre from 1 January 2022 and 30 April 2022. Ethical approval was obtained from the Ethical Review Board (Registration number: 594/2021 P). All patients had their eyes dilated and examined under the slit-lamp with a 90 D convex lens or indirect ophthalmoscopes with a 20 D lens to find retinopathy. All patients aged 40 to 79 years with intermediate hyperglycemia were included in the study. Convenience sampling was used. Point estimate and 95% Confidence Interval were calculated.

RESULTS

Among 141 patients with prediabetes, diabetic retinopathy was found in 8 (5.67%) (1.85-9.49, 95% Confidence Interval). Among which all patients 8 (5.67%) had mild non-proliferative diabetic retinopathy. Among patients with retinopathy, all 8 (5.67%) were obese, 3 (37.50%) were hypertensive, 5 (62.50%) patients had intermediate hyperglycemia for more than 6 months, and 2 (25%) had a family history of diabetes mellitus.

CONCLUSIONS

The prevalence of diabetic retinopathy in prediabetes patient was found to be higher than the other studies conducted in similar settings.

KEYWORDS

diabetic retinopathy; prediabetes; prevalence.