Effect of glycosylated hemoglobin on response to ranibizumab therapy in diabetic macular edema: real-world outcomes in 312 patients

Does HbA1c Level or Glomerular Filtration Rate Affect the Clinical Response to Endothelial Growth Factor Therapy (Ranibizumab or Aflibercept) in Diabetic Macular Edema? A Real-Life Experience

INTRODUCTION

Anti-vascular endothelial growth factor (VEGF) therapy is the first-line treatment for diabetic macular edema (DME). We investigated the effect of initial glycosylated hemoglobin (HbA1c) level and glomerular filtration rate (GFR) on treatment outcomes in patients with DME receiving anti-VEGF injections in routine clinical practice.

METHODS

A retrospective analysis of data from the prospective, multi-center, observational Fight Retinal Blindness! registry was performed. A total of 178 eyes with DME treated with anti-VEGF agents (ranibizumab or aflibercept) from 1 January 2010 to 31 March 2019 were enrolled in the analysis, with the long study period to allow for up to 24 months of follow-up. Data for eyes were tracked in the Fight Retinal Blindness! registry, and clinical parameters were collected by using local software. Changes in visual (best-corrected visual acuity [BCVA], in letters) and anatomic outcomes (central subfield thickness [CST], in microns) between subgroups of patients according to baseline HbA1c level (≤ 7% vs. > 7%) and GFR (> vs. ≤ 60 ml/min/m2 at 24 months were assessed.

RESULTS

The multivariate adjusted mean improvement in BCVA at 24 months of treatment was + 5.2 and + 6.8 letters in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.541), and + 6.9 and + 6.4 letters in subgroups with GFR > 60 and < 60 ml/min/1.73 m2, respectively (p = 0.852). The multivariate adjusted mean CST reduction was - 89.9 and - 76.4 µm in subgroups with baseline HbA1c level ≤ 7% and > 7%, respectively (p = 0.505), and - 85 and - 115 µm in subgroups with baseline GFR > 60 and ≤ 60 ml/min/1.73 m2, respectively (p = 0.130).

CONCLUSION

These results seem to indicate that visual and anatomical improvement in patients receiving intravitreal VEGF inhibitors for DME are independent of baseline HbA1c level and GFR, leading to the conclusion that high HbA1c levels or low GFR should not dictate injection timing in routine clinical practice. This study offers valuable insights for ophthalmologists, enabling a personalized treatment approach and optimizing DME patient outcomes.

The Impact of Laboratory Findings and Optical Coherence Tomography Biomarkers on Response to Intravitreal Anti-VEGF Treatment in Patients with Diabetic Macular Edema

PURPOSE

To investigate potential laboratory and imaging biomarkers as treatment response predictors to intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents in patients with diabetic macular edema (DME).

METHODS

The study included 36 treatment naïve patients with DME, treated with intravitreal anti-VEGF agents and followed-up for 12 months. At baseline, all participants underwent best-corrected visual acuity (BCVA) measurement, dilated fundoscopy, optical coherence tomography, color fundus photography and fluorescein angiography, while full blood count and biochemical analysis of various parameters was also performed. At month 12, treatment response was examined and classified as "favorable" or "non-response". Potential associations between laboratory/imaging biomarkers and treatment response were assessed.

RESULTS

Univariate analysis showed that favorable response at month 12 after initiation of anti-VEGF treatment was correlated with baseline central subfield thickness (CST)≤405 μm (p < .001), absence of subretinal fluid (p = .034), absence of exudates (p = .041), absence of disorganization of the inner retinal layers (p = .037), intact ellipsoid zone (EZ) and external limiting membrane (ELM) (p < .001 and p = .002, respectively), absence of epiretinal membrane (ERM) (p = .040) and absence of macular ischemia (p = .042), while increased lipoprotein(a) was associated with no treatment response (p = .025). At the multivariate analysis, CST was found to be independent predictor of treatment response, while EZ, ELM and ERM were found to predict treatment response perfectly and they could not be entered in the model.

CONCLUSION

Intact EZ and ELM, absence of ERM and CST≤405 μm at baseline can predict favorable treatment response in patients with treatment naïve DME, while no correlation with baseline laboratory parameters was found.

Association Between First- and Third-Month Responses to Intravitreal Ranibizumab for Diabetic Macular Edema

Purpose:

This work examines the relationship between first- and third-month anatomical and visual response with antivascular endothelial growth factor for diabetic macular edema.

Methods:

We prospectively evaluated 58 eyes with center-involved diabetic macular edema. Response was categorized upon the anatomical status after 3 monthly doses based on the reduction of central macular thickness (CMT) from baseline (≥20% or not). Correlation analysis between the anatomical response status, gained letters, optical coherence tomography morphological features, and other baseline characteristics were obtained.

Results:

Twenty-five eyes (43.1%) achieved an anatomical reduction of ≥20% at the third month. Those with a reduction of ≥20% of CMT had subretinal fluid ( P < .01), lower hemoglobin A1c values ( P < .01), lower proportion of intraretinal cysts ( P < .01), a greater anatomical reduction, and visual improvement at the first month of treatment. Multiple logistic regression analysis, showed that the change of CMT after the first injection was an independent predictor for the anatomical reduction of ≥20% after the loading phase ( P < .05). Best corrected visual acuity gain after the first dose showed a significant association with an improvement of ≥10 letters after the loading phase ( P < .05), but not for macular thickness reduction.

Conclusions:

First month anatomical reduction was associated with the anatomical response at 3 months ( P = .042) after monthly ranibizumab therapy. Visual improvement at the first month was predictive only for the visual outcome after the 3 monthly doses ( P = .032).

Evaluation of ranibizumab and aflibercept for the treatment of diabetic macular edema in daily clinical practice

PURPOSE

To evaluate the efficacy and safety of ranibizumab and aflibercept in the treatment of diabetic macular edema in a real world study, and to compare the two treatments with each other.

METHODS

Retrospective observational study of 213 eyes from 141 patients with diabetic macular edema was completed between June 2014 and June 2016. 122 were treated with ranibizumab intravitreal injection and 91 with aflibercept intravitreal injection, with a loading phase of 3 injections and a Pro Re Nata protocol. The drug was selected by the physician and fluorescein angiography was performed by physician`s criteria. Re-treatment was performed when a decline in BCVA, an increase of central macular thickness or an increase or persistence of intraretinal fluid in OCT was observed. The primary outcome was the mean change in best corrected visual acuity at 1 year, while central macular thickness, central macular volume, the number of injections and visits were evaluated as secondary outcomes. The correlation between BCVA at 4th month visit and BCVA at 12th month visit was also evaluated.

RESULTS

The mean baseline best corrected visual acuity for the eyes treated with ranibizumab was 0.55 (+/- 0.35) logMAR, and with aflibercept it was 0.48 (+/- 0.29) (P = 0.109). Best corrected visual acuity improved in both groups, and at the end of the follow-up was 0.40 (+/- 0.35) in the ranibizumab group and 0.40 (+/- 0.29) in the aflibercept group (P = 0.864). Best corrected visual acuity at 4th month visit is correlated at a high value (R = 0.789) with the one at the end of the study. No differences were found in central macular thickness, central macular volume and glycosylated hemoglobin when adjusting with baseline values. The overall number of injections was 5.77 (+/- 2.01), being 5.56 (+/- 2.0) in the ranibizumab group and 6.07 (+/- 1.99) in the aflibercept group (P = 0.069). The main outcome determining final best corrected visual acuity was the baseline best corrected visual acuity (P<0.001).

CONCLUSION

There are no differences in efficacy between ranibizumab and aflibercept in diabetic macular edema treatment in this real world study.