Semaglutide and Diabetic Retinopathy Risk in Patients with Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trials

Association of Glucagon-like Peptide-1 Receptor Agonists with Optic Nerve and Retinal Adverse Events: A Population-Based Observational Study Across 180 Countries

PURPOSE

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are important therapeutic options for type 2 diabetes and obesity; however, concerns about ophthalmic safety persist. This study examined associations between GLP-1 RAs and ocular adverse events (AEs).

DESIGN

Global observational pharmacovigilance study.

METHODS

We searched the US FAERS database (via OpenVigil 2.1) and WHO's VigiBase (via VigiAccess) for optic nerve and retinal AEs associated with semaglutide and tirzepatide, covering the period from their respective approval dates-December 2017 for semaglutide and May 2022 for tirzepatide-through September 2024. In FAERS, all other drugs were compared, while in VigiBase, metformin, empagliflozin, dulaglutide, and insulin served as controls. Disproportionality metrics included reporting odds ratios (RORs) with 95% confidence intervals.

RESULTS

Semaglutide and tirzepatide accounted for 76,444 cases (0.59%) in FAERS (n=12,936,341) and 118,639 cases (0.34%) in VigiBase (n>35,000,000). Semaglutide showed significantly higher odds of ischemic optic neuropathy (ION) (FAERS: ROR=11.12, 95%CI=8.15-15.16; VigiBase: ROR=68.58, 95%CI=16.75-280.67), diabetic retinopathy (DR) (FAERS: ROR=17.28, 95%CI=13.62-21.91; VigiBase: ROR=7.81, 95%CI=5.60-10.90), as well as retinal/vitreous detachment, retinal/vitreous hemorrhage, and retinal tear (FAERS: ROR=2.44-5.89, 95%CI=1.70-8.97, all p<0.001, IC025=0.49, compared to all other drugs. VigiBase: ROR=5.49-20.91, 95%CI=2.71-90.11, all p≤0.0001, IC025≥0.53, compared to metformin). Unique to VigiBase were macular edema (ROR=3.87, 95%CI=1.89-7.92), macular hole (ROR=20.90, 95%CI=2.65-165.01), and papilledema (ROR=6.97, 95%CI=2.53-19.17) (all p≤0.004, IC025≥0.27, compared to metformin). Sensitivity analyses using empagliflozin and dulaglutide revealed significant associations with ION and DR, while vitreous detachment and hemorrhage were significant when compared to dulaglutide. Additionally, when insulin was used as a comparator, semaglutide showed a higher ROR for ION (ROR=9.84, 95%CI=4.25-22.81, P<0.0001, IC025=0.42). However, tirzepatide was only significantly associated with DR in FAERS.

CONCLUSIONS

Given the widespread use of semaglutide, its association with ocular AEs highlight the need for global pharmacovigilance and post-marketing surveillance.

Analysis of Factors Influencing Clinical Inertia in the Treatment of Type 2 Diabetes Mellitus Patients With Metformin

Aims/Background Medication therapy is a crucial measure for type 2 diabetes mellitus (T2DM). However, approximately 50% of diabetes patients in China fail to achieve their blood glucose control targets despite receiving hypoglycemic treatment. Studies have indicated that clinical inertia is often a key factor contributing to poor long-term blood glucose control in most patients. This study aims to investigate the factors influencing clinical inertia in the treatment process of patients using metformin. Methods A retrospective study method was adopted, and 86 T2DM patients treated with metformin who have clinical inertia between June 2021 and June 2023 at Zhejiang Hospital were treated as the inertia group. Additionally, 87 patients who received the same medication treatment and follow-up evaluation without clinical inertia during the same period were selected as the control group. By comparing general data, family and economic situations, lifestyle, and diabetes conditions between the two groups, a logistic multivariate analysis model was used to analyze the factors influencing clinical inertia in the treatment process of T2DM patients using metformin. Results The proportion of male patients and those with an elementary education or below was significantly higher in the inertia group compared to the control group (p < 0.05). Additionally, the proportion of patients without commercial insurance was significantly higher in the inertia group (p < 0.05). The proportion of patients practicing dietary control was lower in the inertia group compared to the control group (p < 0.05). Furthermore, the inertia group had a lower proportion of patients with initial glycated hemoglobin levels ≥8.0%, those conducting home blood glucose monitoring, patients with diabetes-related complications, and those receiving diabetes health education compared to the control group (p < 0.05). Male gender (odds ratio (OR) = 3.487, p = 0.001), elementary education or below (OR = 2.362, p = 0.027), lack of commercial insurance (OR = 3.783, p = 0.005), absence of home blood glucose monitoring (OR = 3.127, p = 0.007), absence of diabetes-related complications (OR = 2.995, p = 0.006), and lack of chronic disease health education (OR = 2.753, p = 0.017) were identified as risk factors for clinical inertia in the treatment of T2DM patients using metformin (p < 0.05). Conclusion The risk of clinical inertia during metformin treatment in T2DM patients is relatively high and is associated with various factors. Targeted intervention measures should be implemented for high-risk populations to reduce the risk of clinical inertia.

Increased vision impairment reports linked to semaglutide: analysis of FDA adverse event data

BACKGROUND

Semaglutide, a GLP-1 receptor agonist widely prescribed for type 2 diabetes and obesity, has recently raised concerns about its ocular safety. This study aimed to investigate the association between semaglutide use and vision impairment using data from the FDA Adverse Event Reporting System (FAERS).

METHODS

We conducted an analysis of FAERS data, comparing reports of vision impairment associated with semaglutide to those associated with other antidiabetic and weight loss medications. The main outcome measure was the reporting odds ratio (rOR) for vision impairment linked to semaglutide use compared to other medications.

RESULTS

Semaglutide showed significantly higher reporting of vision impairment compared to other GLP-1 receptor agonists (rOR 1.95, 95% CI 1.75-2.17, p < 0.0001), DPP-4 inhibitors (rOR 2.46, 95% CI 2.12-2.86, p < 0.0001), SGLT2 inhibitors (rOR 3.89, 95% CI 3.35-4.51, p < 0.0001), and metformin (rOR 2.23, 95% CI 1.90-2.62, p < 0.0001). Similar findings were observed when compared to phentermine (rOR 1.57, 95% CI 1.07-2.31, p = 0.026) and orlistat (rOR 3.77, 95% CI 2.96-4.81, p < 0.0001). Topiramate was the sole exception, showing higher vision impairment reporting than semaglutide (rOR 0.30, 95% CI 0.20-0.45, p < 0.0001).

CONCLUSIONS

These findings suggest a potentially elevated risk of vision impairment with semaglutide use compared to other diabetes and weight loss medications, warranting further investigation and vigilant post-marketing surveillance. Future studies should assess the clinical impact of this potential increased risk on an absolute scale to better inform treatment decisions.

Current Treatment Options for Diabetic Retinal Disease

The global incidence of diabetes is rising steadily and with it the number of people living with diabetic retinal disease (DRD) is increasing. Like diabetes, DRD can be treated but not cured. In response, therapies to address DRD include targeted ocular and systemic medications. This review discusses diabetes and DRD in terms of current screening recommendations, treatments, and considerations related to those therapies and future drug targets and trials on the horizon. This discourse is targeted at all members of the diabetes care team, including primary care providers, optometrists, and ophthalmologists. The dynamic landscape of diabetic retinopathy treatment is promising for the prevention and improvement of visually significant disease.

miR-16-5p Regulates Proliferation and Apoptosis in High Glucose-Treated Human Retinal Microvascular Endothelial Cells by Targeting VEGFA and TGFBR1

Diabetic retinopathy (DR) is a common complication of diabetes and the main cause of vision loss in the middle-aged and elderly people. miRNAs play vital roles in the development of DR. This study aimed to explore the effects of miR-16-5p on high glucose (HG)-stimulated human retinal microvascular endothelial cells (HRECs) by modulating vascular endothelial growth factor A (VEGFA) and transforming growth factor beta receptor 1 (TGFBR1). HRECs were treated with 5 mM, 10 mM, 20 mM, and 30 mM of HG to induce the DR cell model. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of miR-16-5p and mRNAs of VEGFA and TGFBR1. Western blot was used to examine VEGFA and TGFBR1 protein levels. The 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide assay was conducted to test cell proliferation. Flow cytometry with Annexin V-FITC/PI double staining was carried out to assess cell apoptosis ratio. Dual-luciferase assay was used to identify the target relationship between miR-16-5p and VEGFA and TGFBR1. Results found that the expression of miR-16-5p in HG-treated HRECs was reduced, and VEGFA and TGFBR1 expressions were upregulated. Knockdown of miR-16-5p increased VEGFA and TGFBR1 mRNA and protein levels, promoted cell proliferation, and inhibited apoptosis in HG-treated HRECs. VEGFA and TGFBR1 inhibition reversed the effect of knocking down miR-16-5p on HRECs. Dual-luciferase reporter assay revealed that VEGFA and TGFBR1 were the target of miR-16-5p. Overall, knockdown of miR-16-5p enhances proliferation and inhibits apoptosis of HRECs by upregulating VEGFA and TGFBR1 expression.

Glucagon-like Peptide-1 Receptor Agonists in the Management of Diabetic Retinopathy

Glucagon-like peptide-1 (GLP-1) receptor agonists are a family of drugs, most well known by the third-generation once-weekly subcutaneous semaglutide, that act on the incretin pathway of metabolic, hormonal signaling to modulate pancreatic insulin release, gastric emptying, energy intake, and subjective feelings of satiety. This class of drugs' efficacy and safety in the treatment of type 2 diabetes and obesity have been demonstrated across multiple large randomized controlled trials. These data have propelled GLP-1 receptor agonists to ubiquity in diabetic management and weight loss therapy, leading them to be frequently encountered in ophthalmic practice. The effect of GLP-1 receptor agonists like semaglutide on diabetic retinopathy (DR) is at this point unclear; some studies indicate a worsening of DR with the initiation of GLP-1 agonists, especially semaglutide. Overall, the macrovascular reduction of cardiovascular and stroke risks from GLP-1 receptor agonists should be prioritized over the potential microvascular progression of DR, as long as the patient is regularly followed by ophthalmology.

Screening and evaluation of diabetic retinopathy via a deep learning network model: A prospective study

BACKGROUND

Diabetic retinopathy (DR) is one of the most common serious complications in diabetic patients, and early screening and diagnosis are essential to prevent visual impairment. With the rapid development of deep learning technology, network models based on attention mechanisms have shown significant advantages in medical image analysis, which can improve the accuracy and efficiency of screening.

AIM

To evaluate the efficacy of an attention mechanism-based deep learning network model in screening for DR in natural and diabetic populations, as well as in screening with unilateral and bilateral fundus photography.

METHODS

From January 2023 to June 2024, a stratified multistage cluster sampling method was adopted to select a representative sample of permanent residents aged 18-70 years from our hospital. A total of 948 fundus images from 474 participants were included in the "deep learning model" system for scoring. The fundus images were graded via the early treatment of DR [Early Treatment Diabetic Retinopathy Study (ETDRS)] scoring system as the gold standard for the diagnosis of DR. With "DR to be referred (ETDRS > 31)" as the reference variable, a receiver operating characteristic curve was drawn to evaluate the area under the curve (AUC), sensitivity and specificity of the "deep learning model" to determine the screening efficiency of the system.

RESULTS

For each subject, in the natural population, the AUC of using the "deep learning model system" to screen "DR-requiring referral" was 0.941, and the sensitivity and specificity were 98.15% and 90.08%, respectively. The sensitivity and specificity of two-directional fundus photography were 100% and 86.91%, respectively. In the diabetic population, the AUC, sensitivity and specificity were 0.901, 98.08% and 82.10%, respectively, when "wise eye sugar net" unilateral fundus photography was used to screen for "DR-requiring referrals".

CONCLUSION

In both the natural population and the diabetic population, the deep learning model system has shown high sensitivity and specificity and can be used as an auxiliary means of DR screening.

Drug Exposure As a Predictor in Diabetic Retinopathy Risk Prediction Models-A Systematic Review and Meta-Analysis

PURPOSE

To conduct a systematic review to assess drug exposure handling in diabetic retinopathy (DR) risk prediction models, a network-meta-analysis to identify drugs associated with DR and a meta-analysis to determine which drugs contributed to enhanced model performance.

DESIGN

Systematic review and meta-analysis.

METHODS

We included studies presenting DR models incorporating drug exposure as a predictor. We searched EMBASE, MEDLINE, and SCOPUS from inception to December 2023. We evaluated the quality of studies using the Prediction model Risk of Bias Assessment Tool and certainty using GRADE. We conducted network meta-analysis and meta-analysis to estimate the odds ratio (OR) and pooled C-statistic, respectively, and 95% confidence intervals (CI) (PROSPERO: CRD42022349764).

RESULTS

Of 5,653 records identified, we included 28 studies of 678,837 type 1 or 2 diabetes participants, of which 38,579 (5.7%) had DR. A total of 19, 3, and 7 studies were at high, unclear, and low risk of bias, respectively. Drugs included in models as predictors were: insulin (n = 24), antihypertensives (n = 5), oral antidiabetics (n = 12), lipid-lowering drugs (n = 7), antiplatelets (n = 2). Drug exposure was modelled primarily as a categorical variable (n = 23 studies). Two studies handled drug exposure as time-varying covariates, and one as a time-dependent covariate. Insulin was associated with an increased risk of DR (OR = 2.50; 95% CI: 1.61-3.86). Models that included insulin (n = 9) had a higher pooled C-statistic (C-statistic = 0.84, CI: 0.80-0.88), compared to models (n = 9) that incorporated a combination of drugs alongside insulin (C-statistic = 0.79, CI: 0.74-0.84), as well as models (n = 3) not including insulin (C-statistic = 0.70, CI: 0.64-0.75). Limitations include the high risk of bias and significant heterogeneity in reviewed studies.

CONCLUSION

This is the first review assessing drug exposure handling in DR prediction models. Drug exposure was primarily modelled as a categorical variable, with insulin associated with improved model performance. However, due to suboptimal drug handling, associations between other drugs and model performance may have been overlooked. This review proposes the following for future DR prediction models: (1) evaluation of drug exposure as a variable, (2) use of time-varying methodologies, and (3) consideration of drug regimen details. Improving drug exposure handling could potentially unveil novel variables capable of significantly enhancing the predictive capability of prediction models.

Evaluation of systemic medications associated with diabetic retinopathy: a nested case-control study from the UK Biobank

AIMS

This study aims to investigate the associations between commonly used systemic medications and diabetic retinopathy (DR).

METHODS

Individuals with linked primary care prescription data from the UK Biobank were included. Cases were defined as individuals with a Hospital Episode Statistics-coded or primary care recorded diagnosis of DR or self-reported DR. Controls were matched for age, sex, glycosylated haemoglobin, duration of diabetes mellitus (DM), hypertension status and cardiovascular disease status. ORs and 95% CIs were calculated using conditional univariate and multivariable logistic regression models.

RESULTS

A total of 3377 case subjects with DR were included in the study and matched with 3377 control subjects. In multivariable logistic regression, increased odds of incident DR were observed for exposure to short-acting insulins (OR 1.63; 95% CI 1.22 to 2.18), medium-acting insulins (OR 2.10; 95% CI 1.60 to 2.75), sulfonylureas (OR 1.30; 95% CI 1.16 to 1.46). Instead, the use of fibrates (OR 0.71; 95% CI 0.53 to 0.94) and Cox-2 inhibitors (OR 0.68; 95% CI 0.58 to 0.79) was associated with decreased odds of incident DR. Dose-response relationships were observed for all five drug categories (all p<0.05).

CONCLUSIONS

This study comprehensively investigated the associations between systemic medication use and DR and found significant associations between the use of short-acting insulins, medium-acting insulins and sulfonylureas with increased odds of incident DR. In contrast, fibrates and Cox-2 inhibitors were associated with decreased odds of incident DR. These findings may provide valuable insights into DM medication management and serve as a reference for the prevention of DR in patients with DM.

An Investigation of the Correlation Between Retinal Nerve Fiber Layer Thickness with Blood Biochemical Indices and Cognitive Dysfunction in Patients with Type 2 Diabetes Mellitus

Objective

The study aimed to explore the correlation between retinal nerve fiber layer thickness (RNFLT) with blood biochemical indicators and cognitive dysfunction in patients with type 2 diabetes mellitus (T2DM) and the possible mechanism, thereby providing more theoretical basis for the occurrence and prevention of diabetes related complications.

Methods

Eighty T2DM patients treated in our hospital from March 2022 to September 2022 were selected as the study subjects, and the clinical data of the patients were retrospectively analyzed. All patients underwent fundus fluorescein angiography (FFA) to analyze the changes in retinal blood vessels. Patients who met the inclusion criteria were divided as the diabetic retinopathy (DR) group (n=46) and simple diabetes group (n=34). The RNFLT, blood biochemical indexes and changes in cognitive functions of the patients were detected. The correlation between RNFLT with blood biochemical indexes and cognitive dysfunction was analyzed.

Results

Compared with the simple diabetes group, patients in the DR group had much lower mean, nasal, inferior and superior thicknesses (P<0.01). There existed no significant difference in blood pressure, body mass index (BMI), blood lipids (triglycerides, cholesterol, low-density lipoprotein, high-density lipoprotein) between the two groups (P>0.05). Compared with the simple diabetes group, patients in the DR group had much higher fasting blood glucose (FBG), hemoglobin A1c (HbA1c), fasting insulin (FINS), insulin resistance (HOMA-IR) index, apolipoprotein B (ApoB)/apolipoprotein A1 (ApoA1) (P<0.001). Besides, the DR group had sharply lower scores on the Mini-Mental State Examination (MMSE) scale and higher levels of the Trail Making Test-A (TMT-A) and TMT-B (P<0.001). Spearman correlation analysis confirmed that the mean RNFLT was negatively correlated with the levels of FBG, HbA1c, HOMA-IR index, TMT-A and TMT-B (P<0.05), positively correlated with the score of mini-mental state examination (MMSE) (P<0.05), and was no significant correlation with FINS and ApoB/ApoA1 (P>0.05).

Conclusion

DR patients had significantly reduced RNFLT, elevated levels of blood glucose related indicators, and cognitive dysfunction. There existed a correlation between RNFLT and FBG, HbA1c, HOMA-IR index, TMT-A, TMT-B and MMSE.

Use of GLP-1 Receptor Agonists for the Management of Type 1 Diabetes: A Pediatric Perspective

BACKGROUND

Despite all the technological advances in treatment of patients with type 1 diabetes (T1D), glucose control remains suboptimal in most patients. In addition, a relatively high percentage of patients with T1D, including children, have obesity. Therefore, new interventions are required that focus their effects on weight loss, in order to help with associated insulin resistance and improve glycemic control.

SUMMARY

GLP-1 receptor agonists (GLP-1 RAs) have proven to be effective and safe in adults with T1D, showing improvement in glycemic control, body weight and cardiorenal protection. GLP-1 RAs are also approved for children with obesity (above the age of 12 years) or type 2 diabetes (above the age of 10 years). However, currently these medications are not approved for use in children with T1D. Only a few published studies have evaluated their efficacy and safety for this indication.

KEY MESSAGE

This review presents the rationale and experience of add-on GLP-1 RA therapy to pediatric and adolescent patients with T1D, otherwise treated, from RCTs and real-world data. Results of studies of GLP-1 RA in children with T1D are still pending, while large multicenter randomized controlled trials (RCTs) in this population are lacking.

Glucagon-like peptide-1 receptor agonists and risk of sight-threatening retinopathy in Taiwanese population: A propensity based cohort study

AIMS

To compare the risk of vision-threatening retinopathy between glucagon-like peptide-1 receptor agonists (GLP-1 RA) use and no use in patients with type 2 diabetes.

METHODS

Using propensity score matching, we identified 27,506 pairs of GLP-1 RA users and non-users, 3904 pairs of GLP-1 RA and dipeptidyl peptidase-4 inhibitors (DPP-4i) users, 10,985 pairs of GLP-1 RA and sodium-glucose cotransporter-2 inhibitors (SGLT2i) users, 2542 pairs of GLP-1 RA and sulfonylurea, respectively, from Taiwan's National Health Insurance Research Database from January 1, 2009 to December 31, 2018. We used Cox proportional hazards models to compare the risk of vision-threatening retinopathy between GLP-1 RA use and other matched groups.

RESULTS

In the matched cohorts, the time-varying exposure analysis showed that GLP-1 RA use was not associated with an increased risk of vision-threatening retinopathy compared to GLP-1 RA non-use (aHR 0.96, 95 % CI 0.89-1.03). New-user and active-comparator analyses showed that GLP-1 RA was associated with a significantly lower risk of vision-threatening retinopathy than DPP-4i (aHR 0.8, 95 % CI 0.66-0.97) but had no significant association with this risk compared to SGLT2i (aHR 1.09, 95 % CI 0.96-1.24) or sulfonylureas (aHR 0.79, 95 % CI 0.49-1.06).

CONCLUSIONS

This nationwide cohort study showed that GLP-1 RA use was not associated with an increased risk of vision-threatening retinopathy compared to non- GLP-1 RA use, and GLP-1 RA could significantly lower the risk of vision-threatening retinopathy than DPP-4i.

Glucagon-like peptide-1 receptor agonists rescued diabetic vascular endothelial damage through suppression of aberrant STING signaling

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) protect against diabetic cardiovascular diseases and nephropathy. However, their activity in diabetic retinopathy (DR) remains unclear. Our retrospective cohort study involving 1626 T2DM patients revealed superior efficacy of GLP-1 RAs in controlling DR compared to other glucose-lowering medications, suggesting their advantage in DR treatment. By single-cell RNA-sequencing analysis and immunostaining, we observed a high expression of GLP-1R in retinal endothelial cells, which was down-regulated under diabetic conditions. Treatment of GLP-1 RAs significantly restored the receptor expression, resulting in an improvement in retinal degeneration, vascular tortuosity, avascular vessels, and vascular integrity in diabetic mice. GO and GSEA analyses further implicated enhanced mitochondrial gene translation and mitochondrial functions by GLP-1 RAs. Additionally, the treatment attenuated STING signaling activation in retinal endothelial cells, which is typically activated by leaked mitochondrial DNA. Expression of STING mRNA was positively correlated to the levels of angiogenic and inflammatory factors in the endothelial cells of human fibrovascular membranes. Further investigation revealed that the cAMP-responsive element binding protein played a role in the GLP-1R signaling pathway on suppression of STING signaling. This study demonstrates a novel role of GLP-1 RAs in the protection of diabetic retinal vasculature by inhibiting STING-elicited inflammatory signals.

Semaglutide and obesity: beyond the nutritional and lifestyle intervention?

Semaglutide is the second marketed glucagon-like peptide 1 receptor agonist that can be used safely and efficiently in non-diabetic people with excess weight, providing a new milestone in the pharmacological treatment of obesity. This narrative review aims to describe the clinical actions of this new drug in weight management in non-diabetic patients along with possible side-effects and dropout reasons. To accomplish this, the PubMed database was searched to retrieve the most relevant clinical studies published to date on this topic, using the following keywords "semaglutide and obesity". Currently, semaglutide is on the market in two formulations, the once-weekly subcutaneous (s.c.) semaglutide and once-daily oral semaglutide. Data in the literature on the anti-obesity action of semaglutide are available for both routes of administration of the drug, with a prevalence of studies using the s.c. one. However, given its dosage, oral semaglutide may provide greater attractiveness and better treatment adherence, but further research is needed in this field.

Effects of newer-generation anti-diabetics on diabetic retinopathy: a critical review

Diabetic retinopathy (DR) is the leading etiology of blindness in the working population of the USA. Its long-term management relies on effective glycemic control. Seven anti-diabetic classes have been introduced for patients with type 2 diabetes (T2D) in the past two decades, with different glucose-lowering and cardiovascular benefits. Yet, their effects specifically on DR have not been studied in detail. A systematic review of the literature was conducted to investigate this topic, focusing on the available clinical data for T2D. Published studies were evaluated based on their level of statistical evidence, as long as they incorporated at least one endpoint or adverse event pertaining to retinal health. Fifty nine articles met our inclusion criteria and were grouped per anti-diabetic class as follows: alpha-glucosidase inhibitors (1), peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists (8), amylin analogs (1), glucagon-like peptide-1 (GLP-1) receptor agonists (28), dipeptidyl peptidase 4 (DPP-4) inhibitors (9), and sodium glucose co-transporter-2 (SGLT-2) inhibitors (9), plus one retrospective study and two meta-analyses evaluating more than one of the aforementioned anti-diabetic categories. We also reviewed publicly-announced results of trials for the recently-introduced class of twincretins. The available data indicates that most drugs in the newer anti-diabetic classes are neutral to DR progression; however, there are subclasses differences in specific drugs and T2D populations. In particular, there is evidence suggesting there may be worse diabetic macular edema with PPAR-gamma agonists, potential slight DR worsening with semaglutide (GLP-1 receptor agonist), and potential slight increase in the incidence of retinal vein occlusion in elderly and patients with advanced kidney disease receiving SGLT-2 inhibitors. All these warrant further investigation. Longer follow-up and systematic assessment of at least one DR-related endpoint are highly recommended for all future trials in the T2D field, to ultimately address this topic.

Associations of antidiabetic drugs with diabetic retinopathy in people with type 2 diabetes: an umbrella review and meta-analysis

Background

Diabetic retinopathy (DR) is the most frequent complication of type 2 diabetes and remains the leading cause of preventable blindness. Current clinical decisions regarding the administration of antidiabetic drugs do not sufficiently incorporate the risk of DR due to the inconclusive evidence from preceding meta-analyses. This umbrella review aimed to systematically evaluate the effects of antidiabetic drugs on DR in people with type 2 diabetes.

Methods

A systematic literature search was undertaken in Medline, Embase, and the Cochrane Library (from inception till 17th May 2022) without language restrictions to identify systematic reviews and meta-analyses of randomized controlled trials or longitudinal studies that examined the association between antidiabetic drugs and DR in people with type 2 diabetes. Two authors independently extracted data and assessed the quality of included studies using the AMSTAR-2 (A MeaSurement Tool to Assess Systematic Reviews) checklist, and evidence assessment was performed using the GRADE (Grading of recommendations, Assessment, Development and Evaluation). Random-effects models were applied to calculate relative risk (RR) or odds ratios (OR) with 95% confidence intervals (CI). This study was registered with PROSPERO (CRD42022332052).

Results

With trial evidence from 11 systematic reviews and meta-analyses, we found that the use of glucagon-like peptide-1 receptor agonists (GLP-1 RA), sodium-glucose cotransporter-2 inhibitors (SGLT-2i), or dipeptidyl peptidase-4 inhibitors (DPP-4i) was not statistically associated with the risk of DR, compared to either placebo (RR: GLP-1 RA, 0.98, 0.89-1.08; SGLT-2i, 1.00, 95% CI 0.79-1.27; DPP-4i, 1.17, 0.99-1.39) or other antidiabetic drugs. Compared to other antidiabetic drugs, meglitinides (0.34, 0.01-8.25), SGLT-2i (0.73, 0.10-5.16), thiazolidinediones (0.92, 0.67-1.26), metformin (1.15, 0.81-1.63), sulphonylureas (1.24, 0.93-1.65), and acarbose (4.21, 0.44-40.43) were not statistically associated with the risk of DR. With evidence from longitudinal studies only, insulin was found to have a higher risk of DR than other antidiabetic drugs (OR: 2.47, 95% CI: 2.04-2.99).

Conclusion

Our results indicate that antidiabetic drugs are generally safe to prescribe regarding the risk of DR among people with type 2 diabetes. Further robust and large-scale trials investigating the effects of insulin, meglitinides, and acarbose on DR are warranted.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=332052, identifier CRD42022332052.

A Review on Diabetic Retinopathy

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

GLP-1 receptor agonists and diabetic retinopathy: A meta-analysis of randomized clinical trials

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are used to treat type 2 diabetes mellitus. Recent research suggests that GLP-1 RAs may influence diabetic retinopathy (DR). We searched ClinicalTrials.gov for trials comparing FDA-approved GLP-1 RAs to placebo, insulin, or oral antidiabetic medicine. Rates of DR, ocular adverse events, demographics, and clinical characteristics were compared amongst cohorts on 93 trials. GLP-1 RA use was significantly associated with increased risk of early-stage DR (risk ratio (RR) = 1.31, 95% confidence interval (CI) [1.01, 1.68]) and early-stage retinal adverse events (RR = 1.29, 95% CI [1.01, 1.66]) compared to placebo. Compared to insulin, GLP-1 RA use protected against late-stage DR (RR = 0.38, 95% CI [0.15, 0.98]). Analysis of individual GLP-1 RAs showed that albiglutide is responsible for these trends, as it is significantly associated with a higher risk of early-stage DR (RR = 2.18, 95% CI [1.01, 4.67]) compared to placebo and a lower risk of late-stage DR (RR = 0.25, 95% CI [0.09, 0.70]) compared to insulin. Albiglutide similarly affected retinal and ocular adverse events. Demographic analysis revealed significant differences between GLP-1 RA and comparator groups for age, HbA1c, body weight, BMI, duration of diabetes, sex, race, and ethnicity. The influence of GLP-1 RAs on DR and the eye may depend on the specific GLP-1 RA and patient demographic and clinical characteristics.

Incretins and microvascular complications of diabetes: neuropathy, nephropathy, retinopathy and microangiopathy

Glucagon-like peptide-1 receptor agonists (GLP-1RAs, incretin mimetics) and dipeptidyl peptidase-4 inhibitors (DPP-4is, incretin enhancers) are glucose-lowering therapies with proven cardiovascular safety, but their effect on microvascular disease is not fully understood. Both therapies increase GLP-1 receptor agonism, which is associated with attenuation of numerous pathological processes that may lead to microvascular benefits, including decreased reactive oxygen species (ROS) production, decreased inflammation and improved vascular function. DPP-4is also increase stromal cell-derived factor-1 (SDF-1), which is associated with neovascularisation and tissue repair. Rodent studies demonstrate several benefits of these agents in the prevention or reversal of nephropathy, retinopathy and neuropathy, but evidence from human populations is less clear. For nephropathy risk in human clinical trials, meta-analyses demonstrate that GLP-1RAs reduce the risk of a composite renal outcome (doubling of serum creatinine, eGFR reduction of 30%, end-stage renal disease or renal death), whereas the benefits of DPP-4is appear to be limited to reductions in the risk of albuminuria. The relationship between GLP-1RAs and retinopathy is less clear. Many large trials and meta-analyses show no effect, but an observed increase in the risk of retinopathy complications with semaglutide therapy (a GLP-1RA) in the SUSTAIN-6 trial warrants caution, particularly in individuals with baseline retinopathy. Similarly, DPP-4is are associated with increased retinopathy risk in both trials and meta-analysis. The association between GLP-1RAs and peripheral neuropathy is unclear due to little trial evidence. For DPP-4is, one trial and several observational studies show a reduced risk of peripheral neuropathy, with others reporting no effect. Evidence in other less-established microvascular outcomes, such as microvascular angina, cerebral small vessel disease, skeletal muscle microvascular disease and autonomic neuropathies (e.g. cardiac autonomic neuropathy, gastroparesis, erectile dysfunction), is sparse. In conclusion, GLP-1RAs are protective against nephropathy, whereas DPP-4is are protective against albuminuria and potentially peripheral neuropathy. Caution is advised with DPP-4is and semaglutide, particularly for patients with background retinopathy, due to increased risk of retinopathy. Well-designed trials powered for microvascular outcomes are needed to clarify associations of incretin therapies and microvascular diseases.

Correlation between glycated hemoglobin A1c, urinary microalbumin, urinary creatinine, β2 microglobulin, retinol binding protein and diabetic retinopathy

BACKGROUND

Retinopathy is the most common microvascular disease of type 2 diabetes, and seriously threatens the life, health and quality of life of patients. It is worth noting that the development of diabetic retinopathy (DR) can be hidden, with few symptoms. Therefore, the preliminary screening of diabetic patients should identify DR as soon as possible, delay disease progression, and play a vital role in its diagnosis and treatment.

AIM

To investigate the correlation between glycated hemoglobin A1c (HbA1c), urinary microalbumin (U-mALB), urinary creatinine (U-CR), mALB/U-CR ratio, β2 microglobulin (β2MG), retinol binding protein (RBP) and DR.

METHODS

A total of 180 patients with type 2 diabetes mellitus attending the Second People’s Hospital of Hefei from January 2022 to August 2022 were retrospectively enrolled by ophthalmologists. Based on whether they had combined retinopathy and its degree, 68 patients with diabetes mellitus without retinopathy (NDR) were assigned to the NDR group, 54 patients with non-proliferative DR (NPDR) to the NPDR group, and 58 patients with proliferative DR to the PDR group. General data, and HbA1c, mALB, β2MG, RBP, mALB/U-CR and U-CR results were collected from the patients and compared among the groups. Pearson's correlation method was used to analyze the correlation between HbA1c, mALB, β2MG, RBP, mALB/U-CR and U-CR indices, and multiple linear regression was applied to identify the risk factors for DR. Receiver operator characteristic (ROC) curves were also drawn.

RESULTS

The differences in age, gender, systolic and diastolic blood pressure between the groups were not statistically significantly (P > 0.05), but the difference in disease duration was statistically significant (P < 0.05). The differences in fasting blood glucose, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, total cholesterol, and triglyceride between the groups were not statistically significant (P > 0.05). HbA1c in the PDR group was higher than that in the NPDR and NDR groups (P < 0.05). The levels of mALB, β2MG, RBP, mALB/U-CR and U-CR in the PDR group were higher than those in the NPDR and NDR groups (P < 0.05). Multiple linear regression analysis showed that disease duration, HbA1c, mALB, β2MG, RBP, mALB/U-CR and U-CR were risk factors for the development of DR. The ROC curve showed that the area under the curve (AUC) for the combination of indices (HbA1c + mALB + mALB/U-CR + U-CR + β2MG + RBP) was 0.958, with a sensitivity of 94.83% and specificity of 96.72%, which was higher than the AUC for single index prediction (P < 0.05).

CONCLUSION

HbA1c, mALB, mALB/U-CR, U-CR, β2MG and RBP can reflect the development of DR and are risk factors affecting PDR, and the combination of these six indices has predictive value for PDR.

Semaglutide-eye-catching results

Semaglutide is a glucagon-like peptide-1 receptor agonist used either orally every day or subcutaneously once a week for the treatment of type 2 diabetes mellitus and, more recently, at higher doses, for the treatment of obesity. Both diseases are reaching epidemic proportions and often coexist, posing patients with a high risk for cardiovascular disease and death. Therefore, an agent such as semaglutide, which offers clinically significant weight loss and cardiovascular benefits, is essential and will be increasingly used in high-risk patients. However, during the SUSTAIN clinical trial program (Semaglutide Unabated Sustainability in treat-ment of type 2 diabetes), a safety issue concerning the progression and worsening of diabetic retinopathy emerged. The existing explanation so far mainly supports the role of the magnitude and speed of HbA1c reduction, a phenomenon also associated with insulin treatment and bariatric surgery. Whether and to which extent the effect is direct is still a matter of debate and an intriguing topic to investigate for suitable preventative and rehabilitative purposes. In this minireview, we will summarize the available data and suggest guidelines for a comprehensive semaglutide clinical utilization until new evidence becomes available.

The relationship between components of hypoglycemia worries and avoiding hypoglycemia behavior in type 2 diabetes mellitus with hypoglycemia: a network analysis

BACKGROUND

The fear of hypoglycemia in type 2 diabetes mellitus (T2DM) patients with hypoglycemia has seriously affected their quality of life. They are always afraid of hypoglycemia and often take excessive action to avoid it. Yet, researchers have investigated the relationship between hypoglycemia worries and excessive avoiding hypoglycemia behavior using total scores on self-report measures. However, network analysis studies of hypoglycemia worries and excessive avoiding hypoglycemia behavior in T2DM patients with hypoglycemia are lacking.

PURPOSE

The present study investigated the network structure of hypoglycemia worries and avoiding hypoglycemia behavior in T2DM patients with hypoglycemia and aimed to identify bridge items to help them correctly treat hypoglycemia and properly deal with hypoglycemia fear.

METHODS

A total of 283 T2DM patients with hypoglycemia were enrolled in our study. Hypoglycemia worries and avoiding hypoglycemia behavior were evaluated with the Hypoglycemia Fear Scale. Network analyses were used for the statistical analysis.

RESULTS

B9 "Had to stay at home for fear of hypoglycemia" and W12 "I am worried that hypoglycemia will affect my judgment" have the highest expected influences in the present network. In the community of hypoglycemia worries, W17 "I worry about hypoglycemia during sleep" has the highest bridge expected influence. And in the community of avoiding hypoglycemia behavior, B9 "Had to stay at home for fear of hypoglycemia" has the highest bridge expected influence.

CONCLUSION

Complex patterns of associations existed in the relationship between hypoglycemia worries and avoiding hypoglycemia behavior in T2DM patients with hypoglycemia. From the perspective of network analysis, B9 "Had to stay at home for fear of hypoglycemia" and W12 "I am worried that hypoglycemia will affect my judgment" have the highest expected influence, indicating their highest importance in the network. W17 "I worry about hypoglycemia during sleep" aspect of hypoglycemia worries and B9 "Had to stay at home for fear of hypoglycemia" aspect of avoiding hypoglycemia behavior have the highest bridge expected influence, indicating they have the strongest connections with each community. These results have important implications for clinical practice, which provided potential targets for interventions to reduce hypoglycemia fear and improve the quality of life in T2DM patients with hypoglycemia.

Glucagon-like peptide 1-receptor agonists and A1c: Good for the heart but less so for the eyes?

BACKGROUND AND AIMS

Glucagon-like peptide1-receptor agonists (GLP1-RA) decrease major adverse cardiovascular events (MACE) in people with type 2 diabetes mellitus and cardiovascular disease (CVD). Caution is recommended for semaglutide and dulaglutide with risk of exacerbating diabetic retinopathy (DR). Analyses were performed to determine if worsening of DR was dependent on drug class or fall in A1c.

RESEARCH DESIGN AND METHODS

Meta-analyses and meta-regressions (MR) were performed on the 7 major cardiovascular outcome trial (CVOTs) (n = 56004 patients) of GLP1-RA. A second analysis of 11 studies (n = 11894 subjects) with semaglutide documenting DR followed.

RESULTS

Six of the CVOTs evaluated DR. For the GLP1-RA class, there was no increase in the relative rate (rr) for retinopathy (rr = 1.09,95%CI; 0.925,1.289, p = 0.30), with only an increase with parenteral semaglutide (rr = 1.73; 1.10:2.71, p = 0.02). MR showed that decreases in A1c correlated with decreases in MACE (log rr = 0.364∗(Δ A1c), p = 0.014), but increases in DR (log rr= (-0.67∗(ΔA1c), p = 0.076). The change in DR was predominantly found for subcutaneous semaglutide given for >1 year (rr = 1.559,1.068,2.276, p = 0.022) and with decreases in A1c > 1.0% (rr = 1.59; 1.092,2.316, p = 0.016). For the class of GLP1-RA, the rate difference (rd) for worsening retinopathy was = 0.001 (and number needed to harm [NNH] = 1000) compared with rd for MACE = -0.013 (number needed to treat [NNT] = 77). The computation for semaglutide was NNH = 77 and NNT = 43.

CONCLUSIONS

This meta-analysis may assist in decisions balancing the relative risk (of existing retinopathy) versus benefits (to existing CVD). There should be close collaboration with ophthalmology to grade the baseline degree of retinopathy when initiating and following patients.

Will GLP-1 Analogues and SGLT-2 Inhibitors Become New Game Changers for Diabetic Retinopathy?

Diabetic retinopathy (DR) is the most frequent microvascular complication of diabetes mellitus (DM), estimated to affect approximately one-third of the diabetic population, and the most common cause of preventable vision loss. The available treatment options focus on the late stages of this complication, while in the early stages there is no dedicated treatment besides optimizing blood pressure, lipid and glycemic control; DR is still lacking effective preventive methods. glucagon-like peptide 1 receptor agonists (GLP-1 Ras) and sodium-glucose cotransporter 2 (SGLT-2) inhibitors have a proven effect in reducing risk factors of DR and numerous experimental and animal studies have strongly established its retinoprotective potential. Both drug groups have the evident potential to become a new therapeutic option for the prevention and treatment of diabetic retinopathy and there is an urgent need for further comprehensive clinical trials to verify whether these findings are translatable to humans.

Semaglutide for the treatment of type 2 Diabetes Mellitus: A systematic review and network meta-analysis of safety and efficacy outcomes

BACKGROUND AND AIMS

To assess the safety and efficacy of semaglutide compared with placebo and other anti-hyperglycaemic agents in type 2 diabetes (T2DM).

METHODS

We searched PubMed, Scopus, Web of Science, and Cochrane library for relevant randomized controlled trials (RCTs). A network meta-analysis was conducted to compare different doses, durations, and interventions in T2DM. We presented results as mean difference (MD) or relative risk (RR) and 95% confidence interval (CI).

RESULTS

Twenty-six included RCTs studied different doses of subcutaneous (SC) and oral semaglutide, tirzepatide, liraglutide, sitagliptin, canagliflozin, and empagliflozin compared with placebo. Tirzepatide showed the highest efficacy, however, it was comparable to semaglutide. SC semaglutide 1 mg once-weekly showed higher reduction in HbA_1c (MD = -1.72, 95% CI [-2.32; -1.12]), and fasting blood glucose (MD = -1.93, 95% CI [-2.81; -1.04]) versus placebo at 30 weeks and other timepoints. Adverse events (ADs) were comparable to placebo with oral and SC semaglutide, oral sitagliptin, SC liraglutide, and oral empagliflozin at most timepoints. However, SC semaglutide 0.8 mg and tirzepatide 10 mg groups had the highest gastrointestinal adverse events.

CONCLUSION

Tirzepatide, oral and SC semaglutide has a favourable efficacy in treating T2DM. The adverse events were comparable to placebo; however, gastrointestinal adverse events were highly recorded in tirzepatide, oral and SC semaglutide groups.