Glucagon-Like Peptide 1 Receptor Agonists and Risk of Diabetic Retinopathy Complications: Cohort Study in Nationwide Registers From Two Countries

Impact of GLP-1 Agonists and SGLT-2 Inhibitors on Diabetic Retinopathy Progression: An Aggregated Electronic Health Record Data Study

PURPOSE

To examine the effects of glucagon-like peptide-1 receptor (GLP-1) agonists compared to SGLT-2 inhibitors on diabetic retinopathy.

DESIGN

Retrospective clinical cohort study using TriNetX, a federated electronic health records network comprising multiple healthcare organizations.

METHODS

Patients with an International Classification of Diseases, Tenth Revision (ICD-10) code of nonproliferative diabetic retinopathy (PDR) and monotherapy treatment, excluding insulin, with GLP-1 agonists or SGLT-2 inhibitors. Patients with a history of PDR prior to initiation of treatment were excluded. The rate of progression to PDR and rate of development of diabetic macular edema (DME) were compared between patients on GLP-1 agonists compared to those on SGLT-2 inhibitors. The groups were propensity score matched for age, gender, ethnicity, race, type of diabetes, and severity of PDR. Main outcomes included rate and relative risk (RR) of progression to PDR and risk of DME in the GLP-1 agonist group versus the SGLT-2 inhibitor group.

RESULTS

A total of 6481 patients were identified in the GLP-1 cohort and the SGLT-2 inhibitor cohort after propensity score matching. At 1 and 3 years after initiation of therapy, a higher rate of progression of PDR was noted (RR: 1.26, CI 1.04-1.51, P = .017 at 1 year, RR: 1.284, CI 1.1-1.499, P = .002 at 3 years) in the GLP-1 agonist cohort compared to the SGLT-2 inhibitor cohort. There was a higher rate of DME noted at 3 months (RR: 1.192, CI 1.059-1.276, P = .002), 6 months (RR: 1.22, CI 1.13-1.32, P < .001), 1 year (RR: 1.24, CI 1.15-1.33, P < .001), and at 3 years (RR: 1.29, CI 1.21-1.38, P < .001) in the GLP-1 agonist cohort compared to the SGLT-2 inhibitor cohort.

CONCLUSIONS

A higher rate of progression of PDR and risk of new-onset DME was observed in patients on monotherapy with GLP-1 agonists compared to those on SGLT-2 inhibitors. It is important for clinicians to be aware of these potential effects and to consider the current retinopathy status when initiating treatment with newer hypoglycemic agents to ensure these patients are appropriately monitored for developing potential vision-threatening complications.

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.

The incidence of retinopathy in the Glycemia Reduction Approaches in Diabetes: A Comparative Effectiveness study (GRADE)

Based on self-report in the GRADE diabetes study, cumulative incidence of retinopathy was low over 5 years (3.7 %; 184 of 4098 participants) and did not differ among the 4 treatment groups (glargine 4.0 %, glimepiride 3.2 %, liraglutide 3.7 %, sitagliptin 3.8 %). There were no differences in retinopathy with specific therapies in GRADE. Clinicaltrials.gov identifier: NCT01794143.

Glucagon-Like Peptide-1 Receptor Agonist and Risk of Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus: A Systematic Review and Meta-analysis of Randomized Placebo-Controlled Trials

BACKGROUND

Glucagon-like peptide 1 receptor agonists (GLP-1RAs) exhibit glucose-lowering, weight-reducing, and blood pressure-lowering effects. Nevertheless, a debate exists concerning the association between GLP-1RA treatment and the risk of diabetic retinopathy (DR) in patients diagnosed with type 2 diabetes mellitus (T2DM).

OBJECTIVE

To ascertain the risk of DR in patients with T2DM undergoing GLP-1RA treatment, we conducted a meta-analysis utilizing data derived from randomized placebo-controlled studies (RCTs).

METHODS

A comprehensive literature search was conducted using PubMed, Cochrane Library, Web of Science, and EMBASE. We focused on RCTs involving the use of GLP-1RAs in patients with T2DM. Utilizing R software, we compared the risk of DR among T2DM patients undergoing GLP-1RA treatment. The Cochrane risk of bias method was employed to assess the research quality.

RESULTS

The meta-analysis incorporated data from 20 RCTs, encompassing a total of 24,832 T2DM patients. Across all included trials, randomization to GLP-1 RA treatment did not demonstrate an increased risk of DR (odds ratio = 1.17; 95% CI 0.98-1.39). Furthermore, no significant heterogeneity or publication bias was detected in the analysis.

CONCLUSION

The results of this systematic review and meta-analysis indicate that the administration of GLP-1 RA is not associated with an increased risk of DR. PROSPERO REGISTRATION IDENTIFIER: CRD42023413199.

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.

Evaluating the Effect of Hypoglycemic Agents on Diabetic Retinopathy Progression

BACKGROUND AND OBJECTIVE

Newer hypoglycemics such as dipeptidyl peptidase 4 (DPP-4) inhibitors, sodium-glucose cotransporter-2 (SGLT-2) inhibitors, glucagon-like peptide-1 (GLP-1) receptor agonists have been increasingly used in diabetes. This study aimed to assess the relationship between usage of these hypoglycemic agents and effect on diabetic retinopathy (DR).

MATERIALS AND METHODS

Using the Vestrum Health Retina Database, patients with DR with 1 year follow-up after use of a hypoglycemic agent were included and stratified by agent, including no pharmacotherapy.

RESULTS

Of 60,649 eyes, in 1 year after hypoglycemic agent usage, progression rates from severe nonproliferative diabetic retinopathy (NPDR) to proliferative diabetic retinopathy (PDR) were the following: DPP-4 (17%), SGLT-2 (12%), GLP-1 (21%), metformin (18%), and none (20%). Progression rates from moderate NPDR to severe NPDR or PDR were the following: DPP-4 (11%), SGLT-2 (10%), GLP-1 (11%), metformin (10%), none (13%). Progression rates from mild NPDR to moderate/severe NPDR or PDR were the following: DPP-4 (6%), SGLT-2 (9%), GLP-1 (9%), metformin (7%), and none (10%).

CONCLUSIONS

Within a large real-world database, patients prescribed GLP-1 agonists were found to have DR progression rates comparable to those of patients receiving no hypoglycemic agents. [Ophthalmic Surg Lasers Imaging Retina 2023; 54(3):158-165.].

Glucagon-like peptide-1 receptor agonists and diabetic retinopathy: nationwide cohort and Mendelian randomization studies

BACKGROUND

The ability of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) to decrease certain microvascular events has called for the investigation of GLP-1 RAs against diabetic retinopathy (DR), but the evidence is limited. By combining data from observational and Mendelian randomization (MR) studies, we aimed to investigate whether GLP-1 RAs decrease the risk of DR.

METHODS

We combined data from several Swedish Registers and identified patients with incident type 2 diabetes being treated with GLP-1 RAs between 2006 and 2015, and matched them to diabetic patients who did not use GLP-1 RAs as the comparisons. The Cox proportional hazards models were applied to assess the risk of DR. We further performed the summary-data-based MR (SMR) analyses based on the Genotype-Tissue Expression databases and the Genome-Wide Association Study of DR from the FinnGen consortium.

RESULTS

A total of 2390 diabetic patients were treated with GLP-1 RAs and the incidence of DR was 5.97 per 1000 person-years. Compared with diabetic patients who did not use GLP-1 RAs having an incidence of 12.85 per 1000 person-years, the adjusted hazard ratio (HR) of DR was 0.42 [95% confidence interval (CI), 0.29-0.61]. Genetically-predicted GLP1R expression (the target of GLP-1 RAs) showed an inverse association with background [odds ratio (OR)=0.83, 95% CI, 0.71-0.97] and severe nonproliferative DR (OR=0.72, 95% CI, 0.53-0.98), and a non-significant association with overall (OR=0.97, 95% CI, 0.92-1.03) and proliferative DR (OR=0.98, 95% CI, 0.91-1.05).

CONCLUSIONS

Both observational and mendelian randomization analyses showed a significantly lower risk of DR for patients treated with GLP-1 RAs, which calls for further studies to validate these findings.

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

BACKGROUND

Semaglutide is a recently approved glucagon-like peptide-1 receptor agonist used to treat patients with type 2 diabetes mellitus (T2DM). The SUSTAIN 6 trial found a significantly higher rate of retinopathy complications in the semaglutide-treated group compared with the placebo group.

OBJECTIVE

This study aimed to evaluate the association between semaglutide and the risk of retinopathy in patients with T2DM.

METHODS

Electronic databases were systematically searched up to April 2021 to identify randomized controlled trials that reported diabetic retinopathy (DR) events in semaglutide-treated and control groups. A meta-analysis was conducted using Review Manager 5.4 software to calculate the risk ratio (RR) and 95% confidence intervals (CIs).

RESULTS

A total of 23 randomized trials involving 22,096 patients with T2DM were included. There were 730 incident DR cases-463 in the semaglutide group and 267 in the control group. Overall, semaglutide was not associated with increased DR risk compared with controls when all trials were combined (RR 1.14, 95% CI 0.98-1.33). Subgroup analysis showed that semaglutide was associated with an increased risk of DR compared with placebo (RR 1.24, 95% CI 1.03-1.50). Moreover, patient age ≥ 60 years and diabetes duration ≥ 10 years were also factors for increased risk of DR when using semaglutide (RR 1.27, 95% CI 1.02-1.59; RR 1.28, 95% CI 1.04-1.58, respectively).

CONCLUSIONS

Semaglutide was not associated with an increased risk of DR; however, caution regarding DR risk is needed for older patients or those with long diabetes duration when taking semaglutide.

Profiles of Intraday Glucose in Type 2 Diabetes and Their Association with Complications: An Analysis of Continuous Glucose Monitoring Data

Aims: To identify profiles of type 2 diabetes from continuous glucose monitoring (CGM) data using ambulatory glucose profile (AGP) indicators and examine the association with prevalent complications. Methods: Two weeks of CGM data, collected between 2015 and 2019, from 5901 adult type 2 diabetes patients were retrieved from a clinical database in Chennai, India. Non-negative matrix factorization was used to identify profiles as per AGP indicators. The association of profiles with existing complications was examined using multinomial and logistic regressions adjusted for glycated hemoglobin (HbA1c; %), sex, age at onset, and duration of diabetes. Results: Three profiles of glycemic variability (GV) were identified based on CGM data-Profile 1 ["TIR Profile"] (n = 2271), Profile 2 ["Hypo"] (n = 1471), and Profile 3 ["Hyper"] (n = 2159). Compared with time in range (TIR) profile, those belonging to Hyper had higher mean fasting plasma glucose (202.9 vs. 167.1, mg/dL), 2-h postprandial plasma glucose (302.1 vs. 255.6, mg/dL), and HbA1c (9.7 vs. 8.6; %). Both "Hypo profile" and "Hyper profile" had higher odds of nonproliferative diabetic retinopathy ("Hypo": 1.44, 1.20-1.73; "Hyper": 1.33, 1.11-1.58), macroalbuminuria ("Hypo": 1.58, 1.25-1.98; "Hyper": 1.37, 1.10-1.71), and diabetic kidney disease (DKD; "Hypo": 1.65, 1.18-2.31; "Hyper": 1.88, 1.37-2.58), compared with "TIR profile." Those in "Hypo profile" (vs. "TIR profile") had higher odds of proliferative diabetic retinopathy (PDR; 2.84, 1.65-2.88). Conclusions: We have identified three profiles of GV from CGM data. While both "Hypo profile" and "Hyper profile" had higher odds of prevalent DKD compared with "TIR profile," "Hypo profile" had higher odds of PDR. Our study emphasizes the clinical importance of recognizing and treating hypoglycemia (which is often unrecognized without CGM) in patients with type 2 Diabetes Mellitus.

Comparing the use of individual and composite terms to evaluate adverse drug event disproportionality: a focus on glucagon-like peptide-1 receptor agonists and diabetic retinopathy

Background: The SUSTAIN-6 trial showed significantly higher rates of retinopathy complications in the semaglutide group compared to placebo. Observational studies have not consistently corroborated this finding, raising questions about the appropriateness of composite variables and whether the relationship exists across the entire drug class or is limited to individual glucagon-like peptide 1 agonists (GLP-1RAs). The study objective was to evaluate the difference between using individual and composite terms to assess associations between GLP-1RAs and diabetic retinopathy events.Research Design and Methods: Reports from the US Food and Drug Administration Adverse Event Reporting System were utilized to examine relationships between GLP-1RAs and diabetic retinopathy events. A disproportionality analysis was conducted using the proportional reporting ratio.Results: Four GLP-1RAs demonstrated signals for diabetic retinopathy events. The GLP-1RA drug class had four diabetic retinopathy signals. Only semaglutide had a signal for the composite diabetic retinopathy outcome. The GLP-1RA drug class and the composite diabetic retinopathy outcome did not meet the PRR signal thresholds.Conclusions: The use of drug class level and composite outcome variables may mask diabetic retinopathy signals in comparison to individual drug assessments. Our results support the SUSTAIN-6 trial findings and suggest an association between four GLP-1RAs and diabetic retinopathy events.

The present and future scope of real-world evidence research in diabetes: What questions can and cannot be answered and what might be possible in the future?

The last decade has witnessed an exponential growth in the opportunities to collect and link health-related data from multiple resources, including primary care, administrative, and device data. The availability of these "real-world," "big data" has fuelled also an intense methodological research into methods to handle them and extract actionable information. In medicine, the evidence generated from "real-world data" (RWD), which are not purposely collected to answer biomedical questions, is commonly termed "real-world evidence" (RWE). In this review, we focus on RWD and RWE in the area of diabetes research, highlighting their contributions in the last decade; and give some suggestions for future RWE diabetes research, by applying well-established and less-known tools to direct RWE diabetes research towards better personalized approaches to diabetes care. We underline the essential aspects to consider when using RWD and the key features limiting the translational potential of RWD in generating high-quality and applicable RWE. Only if viewed in the context of other study designs and statistical methods, with its pros and cons carefully considered, RWE will exploit its full potential as a complementary or even, in some cases, substitutive source of evidence compared to the expensive evidence obtained from randomized controlled trials.