Association of Blood Glucose Control and Lipids With Diabetic Retinopathy in the Veterans Affairs Diabetes Trial (VADT)

The differences of metabolic profiles, socioeconomic status and diabetic retinopathy in U.S. working-age and elderly adults with diabetes: results from NHANES 1999-2018

AIMS

Controlled metabolic factors and socioeconomic status (SES) was crucial for prevention of diabetic retinopathy (DR). The study aims to assess the metabolic factors control and SES among working-age adults (18-64 years) with diabetes compared to older adults (65 years and older).

METHODS

Totals of 6738 participants with self-reported diagnosed diabetes from National Health and Nutrition Examination Survey were included, of whom 3482 were working-age and 3256 were elderly. The prevalence of DR, metabolic factors control, and the impact of SES and diabetic duration on DR was estimated. Subgroup analysis among working-age adults was employed across different diabetic duration and SES level.

RESULTS

The prevalence of DR was 20.8% among working-age adults and 20.6% in elderly adults. Further, working-age adults possessed suboptimal control on glycemia (median HbA1c: 7.0% vs. 6.8%, p < 0.001) and lipids (Low-density lipoprotein < 100 mg/dL: 46.4% vs. 63.5%, p < 0.001), but better blood pressure control (< 130/80 mmHg: 53.5% vs. 37.5%, p < 0.001) compared to the elderly, judging based on age-specific control targets. Prolonged diabetic duration didn't improve glycemic and composite factors control. SES like education and income impacted metabolic factors control and adults with higher SES were more likely to control well. Diabetic duration was a significant risk factor (OR = 4.006, 95%CI= (2.752,5.832), p < 0.001) while higher income (OR = 0.590, 95%CI= (0.421,0.826), p = 0.002) and educational level (OR = 0.637, 95%CI= (0.457,0.889), p = 0.008) were protective against DR.

CONCLUSIONS

Working-age adults with diabetes demonstrate suboptimal metabolic profile control, especially glycemia and lipids. Additional efforts are needed to improve metabolic factor control and reduce DR risk, particularly for those with longer diabetes duration, less education, and lower incomes.

Prevalence and predictors of developing vision-threatening diabetic retinopathy within the first three years of type 2 diabetes

Purpose

To investigate the prevalence of diabetic retinopathy (DR) and vision-threatening DR (VTDR) in patients with type 2 diabetes mellitus (T2DM) stratified by the duration of diabetes and to identify the clinical variations and risk factors for VTDR occurring at different stages of T2DM.

Methods

This was a retrospective comparative study. Patients were divided into short- (≤3 years), intermediate- (3-7 years), and long-duration (>7 years) groups. All patients were followed-up for DR and VTDR development. Risk factors were explored using logistic regression analysis.

Results

A total of,2961 patients were included; among them, 1,036 (35.0%) patients developed DR, and 293 (9.9%) had VTDR. The frequency of VTDR in patients who developed DR in the short-duration group was significantly higher than that in the intermediate-duration group (25.7% vs. 15.0%; p = 0.019), but comparable with that of the long-duration group (25.7% vs. 31.8%; p = 0.138). Patients who developed VTDR within the first 3 years of T2DM were more likely to have a family history of diabetes (p = 0.024), had higher glycated hemoglobin (p = 0.025), were males (p = 0.042), and were notably older at the onset of diabetes (p <0.001) but younger when diagnosed with DR (p <0.001). Moreover, higher glycated hemoglobin (OR = 1.14; 95% CI: 1.00-1.29; p = 0.043) and diabetic nephropathy (DN) (OR = 2.31; 95% CI: 1.08-4.91; p = 0.030) were independent risk factors for developing VTDR during the first 3 years of T2DM.

Conclusion

The risk of DR is not high in persons with ≤3 years' duration of T2DM, however, if afflicted, the risk of VTDR should never be neglected. More frequent retinal screening is warranted in patients with newly diagnosed T2DM.

Sodium-glucose co-transporter 2 inhibitor add-on therapy for metformin delays diabetic retinopathy progression in diabetes patients: a population-based cohort study

To investigate how sodium-glucose co-transporter 2 inhibitors (SGLT2is) add-on therapy for metformin affects diabetic retinopathy (DR) progression in patients with type 2 diabetes mellitus (T2DM). This nationwide population-based study conducted from January 1, 2016, to December 31, 2018 involved 3,432,911 adults with T2DM in Taiwan. To adjust for potential confounders, data on sex, age, income, comorbidities, diabetes complication severity index score, staging of kidney disease, anti-diabetic medications, and index year were included. The outcome was DR progression, determined by procedure codes or the addition of ICD-9-CM or ICD-10-CM codes to the medical records of the patients during the study. Sensitivity analyses were performed to validate the findings. The adjusted hazard ratio (aHR) of DR progression was 0.89 for the SGLT2is add-on group, relative to the control group [95% confidence interval (CI) 0.81-0.99, P = 0.026]. The Kaplan-Meier curve of the cumulative incidence rate showed that the cumulative incidence of DR progression was considerably decreased in the SGLT2is cohort (log-rank P = 0.0261). The use of SGLT2is for less than 1 year and 1-2 years were associated with a significant increase in the risk of DR progression (aHR 1.56 and 1.88, respectively); however, the risk markedly reduced if the SGLT2is regimen was used for more than 2 years (aHR 0.41, 95% Cl 0.35-0.48; P < 0.001). The serial sensitivity analysis showed consistent findings. The aHR of DR progression was 0.82 for the SGLT2is cohort relative to the non-SGLT2is cohort based on the fundoscopy or indirect ophthalmoscopy findings within 1 year before the outcome date (95% Cl 0.71-0.95; P = 0.009). Co-administration of metformin and SGLT2is may reduce the risk of DR progression. Short-term use of SGLT2is may markedly increase the risk of DR, whereas prolonged use SGLT2is may significantly decrease it.

Association Between Increased Lipid Profiles and Risk of Diabetic Retinopathy in a Population-Based Case-Control Study

Purpose

We aimed to investigate the association between lipid profiles and diabetic retinopathy (DR).

Patients and Methods

This case-control study, which was conducted between November 2019 and August 2021, comprised 309 patients with DR, 186 patients with diabetes mellitus, and 172 healthy controls. Serum cholesterol (CHOL), triglyceride (TRIG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), small dense LDL-C (SDLDL-C), apolipoprotein A (APOA), APOB, APOE and lipoprotein (a)(LPA) levels were assessed. Patients were divided into two groups according to median age and glycated hemoglobin (HbA1c) level. Linear and logistic regression analyses were performed to assess the association between lipid levels and DR.

Results

CHOL, TRIG, HDL-C, APOB, APOE, and SDLDL-C levels were significantly higher in the DR group than in the healthy control group, and TRIG levels were lower in the DR group than in the DM group (P < 0.05), especially in the ≤57-year-old and the HbA1c ≤7.2% subgroups. Linear regression analyses showed that CHOL, TRIG, APOA, APOB, APOE, and SDLDL-C levels were associated with HbA1c levels. Multivariable logistic regression analyses indicated that CHOL (odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.112–1.566), TRIG (OR = 1.269, 95% CI = 1.030–1.563), HDL-C (OR = 43.744, 95% CI = 17.12–111.769), APOB (OR = 7.037, 95% CI = 3.370–14.695), APOE (OR = 1.057, 95% CI = 1.038–1.077), and SDLDL-C (OR = 14.719, 95% CI = 8.304–26.088) levels were risk factors for DR (P < 0.05).

Conclusion

Increased lipid levels were risk factors for DR, and lipid level control should be strengthened, especially in younger adults or in patients with HbA1c ≤7.2%.

Early Worsening of Retinopathy in Type 1 and Type 2 Diabetes After Rapid Improvement in Glycaemic Control: A Systematic Review

To systematically review the epidemiology of early worsening of diabetic retinopathy (EWDR) after substantial improvements in glycaemic control and evaluate characteristics including risk factors. This systematic review was registered with PROSPERO (CRD42020158252). An electronic literature search was performed according to PRISMA guidelines using MEDLINE, EMBASE, PubMed, Web of Science, Scopus and Cochrane databases and manual reference for the articles published until 2020. Published full-text English language articles that report data on diabetic retinopathy in people with diabetes experiencing a rapid, substantial decrease in HbA1c after going through intensive therapy were included. All articles were screened, data were extracted and methodological quality was evaluated by two independent reviewers using a priori criteria. A total of 346 articles were identified after the removal of duplicates. Data were extracted from 19 full-text articles with a total of 15,588 participants. Included studies varied considerably in terms of patient selection, timing and method of assessing the eye and retinopathy classification. EWDR was reported to occur in a wide range of prevalences; 3.3-47% of participants within 3-84 months after intensification of glycaemic control. Risk factors for EWDR included long duration of diabetes, long-term uncontrolled hyperglycemia, amplitude of and baseline retinopathy severity in both type 1 and type 2 diabetes. The occurrence of EWDR and progression of retinopathy were found to have an association with the amplitude of HbA1c reduction. EWDR has been described in a proportion of people with intensification of glycaemic control. However, the prevalence remains unclear because of methodological differences in the identified studies. Future interventional studies should report retinopathy and visual outcomes using standardized protocols.

Eye Outcomes in Veteran Affairs Diabetes Trial (VADT) After 17 Years

OBJECTIVE

The objective of this study was to assess the long-term role of intensive glycemic control (INT) compared with standard glycemic control in accumulated eye procedures in patients with advanced diabetes.

RESEARCH DESIGN AND METHODS

We compared the effect of treatment assignment on the accumulated number of eye procedures during the intervention period of the Veteran Affairs Diabetes Trial (VADT) (2000-2008) (median follow-up 5.6 years), the interim VADT follow-up study (2000-2013), and the full 17 years of VADT follow-up (2000-2017). We further analyzed data using various cardiovascular markers in two models. Model I included total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, systolic and diastolic blood pressure, and BMI. Model II included these covariates plus age and diabetic retinopathy (DR) severity score at baseline of the original trial.

RESULTS

The final analysis of the data showed a mild but nonsignificant increase in number of procedures and in retinal or retinal plus cataract surgery during the three periods of the study.

CONCLUSIONS

We found no significant benefit of INT during the original trial period in eye-related procedures, such as various procedures for DR, or during the 17 years of follow-up in cataract surgery. However, after adjusting data for some known vascular markers, the increase in the number of eye procedures with INT becomes more prevalent. This finding indicates that INT might not have a protective role in events requiring surgery in individuals with advanced diabetes.

Review of the veteran affairs diabetes trial: Lessons learned

Despite robust evidence linking long-term hyperglycemia with cardiovascular complications, several large randomized trials found only modest benefits from intensive compared to standard glucose control. Of these trials, the Veteran Affairs Diabetes Trial (VADT), offers a unique long-term perspective in that there were analyses of outcomes at the end of the intervention trial, 5-years post-trial, and after 10-years post-trial. From the VADT and other large trials, we draw several valuable lessons that are relevant to the care of patients with type 2 diabetes. Intensive glucose control reduces development of nephropathy and retinopathy but not neuropathy, though evaluations of neuropathy are less consistent and conclusions regarding outcomes less reliable. While the VADT did not demonstrate reduction in cardiovascular outcomes at completion of the glucose lowering intervention, it did demonstrate a 17% reduction 5-years post-trial, which waned by 10-years post-trial observation. Of interest, the 5-year post trial period included 3 additional years of HbA1c separation between treatment groups which suggests that longer-term glucose control may be needed before benefits are seen. Other factors including hypoglycemia and increased glucose variation are also associated with cardiovascular events and are more prevalent during intensive glucose control, potentially lessening the benefit of lowering average glucose levels. Finally, intensive glucose control requires substantial effort from both the patient and clinician perspective. All of these factors must be kept in mind when considering the benefits of aggressive glucose control for each patient.

How to perform better intervention to prevent and control diabetic retinopathy among patients with type 2 diabetes: A meta-analysis of randomized controlled trials

This meta-analysis of randomized controlled trials (RCTs) aims to investigate how to perform better interventions targeting modifiable risk factors of diabetic retinopathy (DR) to prevent and control DR in patients with type 2 diabetes by comparing different intervention types and follow-up intervals. Literature published before June 1st, 2019 were searched on Pubmed, Embase and ScienceDirect. RCTs targeting modifiable risk factors of DR (including blood glucose, blood pressure, lipid, dietary, physical activity and smoking) were selected by two reviewers and double checked for accuracy. Random effects models were estimated to calculate pooled Odds Ratios (OR). Twenty-two RCTs (n = 22,511) were included. In general, interventions targeting modifiable risk factor of DR reduced the risk of developing DR (I² = 26.7%; OR = 0.60; 95% CI 0.45 to 0.79) and DR worsening (I² = 0.0%; OR = 0.62; 95% CI 0.47 to 0.80; P < 0.001). Multifactorial interventions had better effect on reducing the risk of development and progression of DR in comparison with other interventions, while only blood-pressure-control interventions showed significant effect on slowing down DR worsening. Additionally, interventions with follow-up >5 years had better effect on reduction of DR development, and interventions with follow-up >2 years had better effect on reducing the risk of DR worsening.

Association of the Serum Total Cholesterol to Triglyceride Ratio with Diabetic Retinopathy in Chinese Patients with Type 2 Diabetes: A Community-Based Study

INTRODUCTION

The relationship of total cholesterol (TC) or triglyceride (TG) to diabetic retinopathy (DR) has proven difficult to determine. In addition, there is no report of any study of the correlation between the TC/TG ratio and DR. This study was therefore undertaken to investigate the relationship between the TC/TG ratio and DR in Chinese adults with type 2 diabetes mellitus.

METHODS

A community-based study was conducted from August to October 2014 in Fengyutan, Shenyang, China. DR was assessed based on the modified Airlie House classification of DR. Multivariable logistic regression models were used to evaluate the association between the TC/TG ratio and the presence of DR.

RESULTS

Among the 420 diabetic participants in the study (157 men; mean (SD) age 61.7 (10.0) years), 76 (18.1%) presented with DR. When the TC/TG ratio was analyzed categorically, participants with T2DM in tertile 2 (i.e., TC/TG 2.91-4.00) were more likely (OR 2.01; 95% CI 1.01-3.99) to suffer from DR than patients in tertile 1 (i.e., TC/TG < 2.91) in multivariable models. Similarly, participants in tertile 3 (TC/TG > 4.00) were more likely (OR 2.59; 95% CI 1.11-3.14; P = 0.011) to suffer from DR than patients in tertile 1. This association persisted when the TC/TG ratio was analyzed continuously (P = 0.014).

CONCLUSION

We found a novel positive association between TC/TG ratio and presence of DR in Chinese individuals with T2DM. Although longitudinal data are needed, this finding contributes to the accumulating evidence that a high TC/TG ratio may be implicated in DR.

Worsening of diabetic retinopathy with rapid improvement in systemic glucose control: A review

Worsening of diabetic retinopathy (DR) is associated with the initiation of effective treatment of glycaemia in some patients with diabetes. It has been associated with risk factors such as poor blood-glucose control and hypertension, and it manifests prior to the long-term benefits of optimizing glycaemic control. The majority of evidence supports an association of large and rapid reductions in blood-glucose levels with early worsening of DR. Despite a general awareness of early worsening within the diabetes community, mechanisms to explain the phenomenon remain speculative. We provide an overview of early worsening of DR and its pathophysiology based on current data. We describe the phenomenon in various settings, including in patients receiving insulin- or non-insulin-based treatments, in those undergoing bariatric surgery, and in pregnant women. We discuss various mechanisms and theories that have been suggested to explain this paradoxical phenomenon, and we summarize the implications of these in clinical practice.

The United Kingdom Diabetic Retinopathy Electronic Medical Record Users Group: Report 3: Baseline Retinopathy and Clinical Features Predict Progression of Diabetic Retinopathy

PURPOSE

To determine the time and risk factors for developing proliferative diabetic retinopathy (PDR) and vitreous hemorrhage (VH).

DESIGN

Multicenter, national cohort study.

METHODS

Anonymized data of 50 254 patient eyes with diabetes mellitus at 19 UK hospital eye services were extracted at the initial and follow-up visits between 2007 and 2014. Time to progression of PDR and VH were calculated with Cox regression after stratifying by baseline diabetic retinopathy (DR) severity and adjusting for age, sex, race, and starting visual acuity.

RESULTS

Progression to PDR in 5 years differed by baseline DR: no DR (2.2%), mild (13.0%), moderate (27.2%), severe nonproliferative diabetic retinopathy (NPDR) (45.5%). Similarly, 5-year progression to VH varied by baseline DR: no DR (1.1%), mild (2.9%), moderate (7.3%), severe NPDR (9.8%). Compared with no DR, the patient eyes that presented with mild, moderate, and severe NPDR were 6.71, 14.80, and 28.19 times more likely to develop PDR, respectively. In comparison to no DR, the eyes with mild, moderate, and severe NPDR were 2.56, 5.60, and 7.29 times more likely to develop VH, respectively. In severe NPDR, the eyes with intraretinal microvascular abnormalities (IRMA) had a significantly increased hazard ratio (HR) of developing PDR (HR 1.77, 95% confidence interval [CI] 1.25-2.49, P = .0013) compared with those with venous beading, whereas those with 4-quadrant dot-blot hemorrhages (4Q DBH) had 3.84 higher HR of developing VH (95% CI 1.39-10.62, P = .0095).

CONCLUSIONS

Baseline severities and features of initial DR are prognostic for PDR development. IRMA increases risk of PDR whereas 4Q DBH increases risk of VH.

Predictors of Development and Progression of Retinopathy in Patients with Type 2 Diabetes: Importance of Blood Pressure Parameters

Diabetic retinopathy (DR) is a chronic microvascular complication associated a worse prognosis. We aimed to evaluate the predictors of development/progression of DR in a cohort of 544 high-risk patients with type 2 diabetes who had annual ophthalmologic examinations over a median follow-up of 6 years. Ambulatory blood pressure (BP) monitoring and aortic stiffness by carotid-femoral pulse wave velocity were performed. Multivariate Cox survival analysis examined the independent predictors of development or progression of DR. During follow-up, 156 patients either newly-developed or worsened DR. Patients who developed/progressed DR had longer diabetes duration, higher ambulatory and clinic BP levels, higher aortic stiffness, and poorer glycemic control than patients who did not developed/progressed DR. After adjustments for baseline retinopathy prevalence, age and sex, a longer diabetes duration (p < 0.001), higher baseline ambulatory BPs (p = 0.013, for 24-hour diastolic BP), and higher mean cumulative exposure of HbA_1c (p < 0.001), clinic diastolic BP (p < 0.001) and LDL-cholesterol (p = 0.05) during follow-up were the independent predictors of development/progression of DR. BP parameters were only predictors of DR development. In conclusion, a longer diabetes duration, poorer glycemic and lipid control, and higher BPs were the main predictors of development/progression of DR. Mean cumulative clinic diastolic BP was the strongest BP-related predictor.