Fluctuations in macular thickness in patients with diabetic macular oedema treated with anti-vascular endothelial growth factor agents

Purpose To evaluate retinal thickness fluctuations in patients with diabetic macular oedema (DMO) treated with anti-vascular endothelial growth factor (anti-VEGF) injections. Methods Visual acuity (VA) and central subfield thickness (CST) were collected at baseline, 3, 6, 9 and 12 months. Retinal thickness fluctuation was quantified by standard deviation (SD) of CST across 12 months. A mixed effects regression model evaluated the relationship between CST SD and VA at 12 months. Multiple linear regression analysis was performed to investigate predictors of CST SD. Results Mean baseline and 12-month VAs were 63.5 +/- 15.7 and 69.0 +/- 13.8 Early Treatment of Diabetic Retinopathy Study (ETDRS) letters (change = +5.1 +/- 16.1 letters, p < 0.001). Mean baseline and 12-month CSTs were 396.9 +/- 109.7 and 337.7 +/- 100.7 mu m (change = -59.2 +/- 114.8 mu m, p < 0.001). Retinal thickness variability across the first 12 months was 59.4 +/- 43.6 mu m. Stratification of patient eyes by CST SD demonstrated 9.7 letters difference in 12-month VA between first and fourth quartiles. Significant predictors of CST SD include baseline CST, injection type, laser treatment, and DR stage. Conclusions Larger retinal thickness fluctuations are associated with poorer visual outcomes in eyes with DMO treated with anti-VEGF injections. Retinal thickness variability may be an important prognostic biomarker for DMO patients.