Abstract
Purpose :
While intravitreal anti-vascular endothelial growth factor (VEGF) therapy revolutionized the treatment of diabetic macular edema (DME), there remains a proportion of afflicted eyes that do not achieve optimal visual acuity (VA) outcomes. Previous studies have shown that the amount of fluctuation in macular thickness may be associated with worse VA outcomes in multiple exudative retinal diseases. The current study assessed this relationship among patients with DME undergoing prolonged anti-VEGF therapy.
Methods :
Medical records were retrospectively reviewed for patients diagnosed with treatment naïve DME between January 2016 and August 2017. Eyes were included if they had an anti-VEGF injection ≤31 days of initial diagnosis, a follow up period ≥44 weeks, and ≥3 central subfield thickness (CST) measurements. Fluctuations in CST were determined by standard deviation (SD) of CST measurements across visits. Statistical analysis included Chi-squared test and one-way analysis of variance (ANOVA).
Results :
242 eyes from 170 subjects were included in the current study. Mean CST at baseline and final visit was 353.1 µm (95% CI, 341.3-364.8) and 285.6 µm (95% CI, 276-296), respectively; mean SD was 46.2 µm (95% CI, 39.9-52.4). Mean number of visits was 21.8 (range, 4-67) and mean length of follow up was 149 weeks (range, 51-230.3). 41.7% of eyes received laser treatment with a mean 17.2 anti-VEGF injections (95% CI, 15.9-18.5). Eyes were stratified into quartiles based on CST SD. From the first (lowest SD) to fourth (highest SD) quartile, final VA was 0.32 (20/40 Snellen equivalent), 0.34 (20/40), 0.43 (20/50), and 0.62 (20/80) logMAR (p=0.0004), respectively, with a mean 13.8, 17.1, 18.4, and 19. 5 anti-VEGF injections (p=0.01). Pairwise comparisons showed quartile 1 received significantly fewer injections and quartile 4 demonstrated significantly worse final VA compared to other quartiles (p<0.05). There were no significant differences between quartiles in length of follow up, number of visits, or laser treatment status (p>0.05).
Conclusions :
The current study demonstrated increased CST fluctuations resulted in worse VA outcomes, consistent with other studies involving exudative retinal diseases. Also, decreased CST fluctuations was associated with fewer anti-VEGF injections, while length of follow up, number of visits, and laser treatment status were not similarly associated.
This is a 2021 ARVO Annual Meeting abstract.