Abstract
Purpose :
Inherited retinal diseases (IRDs) are a significant cause of blindness worldwide. One treatment approach is to modulate metabolism in the retina as energy failure is hypothesized to be a cause of photoreceptor degeneration. Metformin is commonly used to treat type 2 diabetes, and emerging evidence suggests that it may protect against retinal degeneration. Thus, we conducted a retrospective study to assess the effects of metformin on IRD progression.
Methods :
Subjects were selected from patients with IRDs who visited the UF Health Eye Center between 2012 and 2022. Medical records were screened for the diagnosis of IRD, metformin use, and follow-up time 6 months or longer. Subjects with IRD without taking metformin were selected as the controls. Disease progression was assessed by best corrected visual acuity (BCVA), central retina thickness (CRT), total macular volume (TMV), presence of epithelial retinal membrane (ERM), and presence of cystoid macular edema (CME). Disease progression was evaluated at initial visit and follow up visit.
Results :
Mean follow up time for metformin group (n=12) was 31.6 months and 34.8 months for control group (n=12). There were no differences in baseline and follow up BCVA. There were no differences in baseline CRT. However, the CRT change in the treatment group is -17±28um, which is significantly different from 25±57um (p=0.002) in the control group. There were no differences in baseline TMV. However, the TMV change of treatment group is 0.17±0.74 mm3, which is significantly different from 0.88±1.36 mm3 (p=0.028) in the control group. There were no differences in CME and ERM status between treatment and control group.
Conclusions :
There was no significant difference in BCVA change, CME, or ERM status, but patients in the metformin group had significantly thinner retinas and smaller macular volumes. There were some limitations of this study. We only have a small number of IRD patients using metformin. The presence of CME may have confounded CRT and TMV results, and the 1:1 case-control ratio limited the power. In future work, multicenter study is needed to investigate the effect of metformin on IRDs. Patients with CME will be excluded from the study. Additionally, a 1:4 case-control ratio will be used.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.