Abstract
Purpose :
To study whether patients with diabetic retinopathy (DR) who have lower mean hemoglobin A1c levels had either a decrease of total anti-VEGF intravitreal injections, or an increase in interval between injections.
Methods :
Retrospective chart review of DR patients at the Yale Eye Center including Hb A1c values, the number of anti-VEGF injections, and the intervals between anti-VEGF injections. Inclusion criteria were adults with DR who received anti-VEGF injections and regular A1c tests. Exclusion criteria were other retinal pathologies, inconsistent follow-up, or deferment of anti-VEGF treatment. Patients were divided up into two groups, those with anti-VEGF treatment and those with both anti-VEGF and panretinal photocoagulation (PRP) therapy. These two groups were further divided with mean A1c either > or < 7%, and into A1c tertiles. Welch’s t-test was performed.
Results :
In patients who received only anti-VEGF treatment (n=60), there was a significant difference in the number of injections (p=0.006) between the middle (7.7 inj.) and top (3 inj.) tertiles of average A1c. There was also a difference (p=0.024) in interval between the bottom (1.3 months) and middle (1.8 months) tertiles of A1c. There was no statistically significant differences in either mean number of injections or mean interval between injections when comparing groups with mean A1c<7 and >7. In the group who received anti-VEGF and PRP (n=79), there were no significant differences in mean number of injections or mean interval between injections in groups with A1c<7 and >7 or when comparing tertiles.
Conclusions :
Individuals with average A1c below 7 did not have a decrease in number of anti-VEGF injections when compared with those with A1c>7. Surprisingly, in some cases the higher tertiles of A1c were found to have a lower mean of injections, as well as increased time between injections. One possible explanation is that those with poor glycemic control may refuse treatment and are less likely to follow up with care regularly.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.