Natural history of diabetic macular edema and factors predicting outcomes in sham-treated patients (MEAD study)

Abstract

Purpose To describe the natural history of diabetic macular edema (DME) with respect to best-corrected visual acuity (BCVA) and central retinal thickness (CRT) outcomes and to identify baseline patient characteristics and systemic factors associated with improvement or worsening of outcomes in sham-treated patients. Methods The study population was sham-treated patients (n = 350) in the 3-year MEAD registration study of dexamethasone intravitreal implant for treatment of DME. Patients had center-involved DME and received sham intravitreal injections in the study eye at ≥ 6-month intervals. Potential prognostic factors for outcomes were evaluated using multiple linear regression analysis. Results Visual and anatomic outcomes were poorer in patients who left the study early (n = 198) than in study completers (n = 152). Mean change in BCVA from baseline at the last visit with available data was + 0.9 letters; 37.5% of patients had no change in BCVA, 23.2% had gained > 10 letters, and 16.0% had lost > 10 letters. Older age and baseline diabetic retinopathy score > 6 were associated with worse BCVA outcomes; thicker baseline CRT and larger number of hypertension medications used were associated with larger reductions in CRT during the study. Conclusions BCVA and CRT outcomes were variable in this population of DME patients with generally good glycemic control. In DME patients without active treatment, older age and baseline diabetic retinopathy score > 6 were associated with less improvement in BCVA; thicker baseline CRT and a larger number of antihypertensive medications used predicted better improvement in CRT. Trial registration The MEAD study trials are registered at ClinicalTrials.gov with the identifiers NCT00168337 and NCT00168389. Keywords Diabetic macular edema. Natural history. Prognosis. Risk factors. Visual acuity MEAD study group members are listed in Appendix 1.

Natural History and Predictors of Vision Loss in Eyes With Diabetic Macular Edema and Good Initial Visual Acuity

“…Our results are consistent with the natural history findings of 350 patients with DME in the MEAD study, where older age and worse baseline DR severity scores were associated with worse BCVA outcomes. 27 We also confirmed the findings from a post-hoc analysis of Protocol V, where observed eyes with worse DR severity were also more likely to require antivascular endothelial growth factor treatment during the 2 years study. 16 Although some studies suggest that HbA1c could be used to stratify the monitoring frequency of untreated DME, with eyes with HbA1c ≥8.5% being 5.7 times more likely to develop CST thickening, 28 neither our study or Protocol V found HbA1c to be a useful predictor of vision loss.…”

“…In this study, we followed the natural history of 48 patients with treatment-naïve DME and good baseline visual acuity (Snellen equivalent of 20/25 or better) similar to those from DRCR Protocol V's observation arm, and analyzed various baseline clinical and anatomic characteristics that may predict greater risk for a vision loss event, defined as visual acuity loss of $2 Snellen lines at any visit or 1 to 2 lines at two consecutive visits, based on the threshold for initiating aflibercept therapy in Protocol V. We found that the clinical factors most strongly associated with vision 27 We also confirmed the findings from a post-hoc analysis of Protocol V, where observed eyes with worse DR severity were also more likely to require antivascular endothelial growth factor treatment during the 2 years study. 16 Although some studies suggest that HbA1c could be used to stratify the monitoring frequency of untreated DME, with eyes with HbA1c $8.5% being 5.7 times more likely to develop CST thickening, 28 neither our study or Protocol V found HbA1c to be a useful predictor of vision loss.…”

COVID-19 Pandemic Lockdowns’ Impact on Visual Acuity of Diabetic Macular Edema: A Large Cohort

“…In addition, when dividing the patients into three categories based on the number of letters lost (0–5, 5–10, >10), no significant difference was found between the 2 years. These results consist of long-term studies such as the MEAD and VISION [ 23 , 24 ] and can be attributed to the undertreatment in real life or to the progression of the disease despite treatment.…”

General health of patients with diabetic macular edema—The LIPSIA study

“…A post-hoc analysis of sham-treated eyes in the MEAD study revealed a significantly better 3-year result in eyes without prior hypertension (difference: +5.8 letters). Furthermore, anatomically better results were found in eyes with anti-hypertensive therapy [ 22 ], suggesting a positive effect of anti-hypertensive treatment on edema reduction.…”