Abstract
Purpose :
There is currently a lack of evidence surrounding the efficacy of insulin therapy compared to oral anti-diabetic therapy as it pertains to diabetic eye disease. We performed a retrospective, observational clinical study that compared the visual acuities (VA) of diabetic patients based on medication regimen and the severity of diabetic retinopathy (proliferative: PDR, severe, moderate, and mild nonproliferative: NPDR, and neovascular glaucoma: NVG).
Methods :
A retrospective consecutive case series was conducted with 170 patients with diabetic eye disease. They were subdivided into 5 groups based on their diagnosis. Two cohorts for each subdivided group were examined: patients taking insulin therapy and patients taking oral anti-diabetic therapy. VA were collected for each patient at baseline, 3 months follow up, 6 months follow up, and 1 year follow up. Statistical analysis using a general linear model with correlated errors was done to identify differences between groups at each time point as well as rates of VA change between groups for each period of follow up.
Results :
Patients with PDR on insulin therapy showed a statistically significant increase in VA from baseline to 3 months (20/77 to 20/62, p=0.041). In patients with severe NPDR there was a statistically significant difference in VA between the two groups at both baseline and 3 months of follow up (insulin therapy group baseline: 20/44, oral anti-diabetic therapy baseline: 20/126, p=0.009; insulin therapy group 3 months: 20/46, oral anti-diabetic therapy 3 months: 20/120, p=0.013). The insulin therapy group showed a significant decline from baseline to 12 months (20/44-20/77, p=0.010) The mild and moderate NPDR groups did not show any statistically significant difference at any time point during the study.
Conclusions :
There is currently not enough evidence overall to suggest a significant difference in outcomes (VA) between patients taking insulin therapy versus patients taking oral anti-diabetic therapy. There may be an implication for more aggressive initial management of patients diagnosed with severe NPDR and PDR due to significant VA differences between patients managed with insulin when compared to patients managed with oral therapy alone. This study ultimately suggests that patients on either treatment regimen will attain similar results from an ophthalmic care standpoint. Therefore, treatment should be guided by appropriate blood sugar control and not influenced by ocular outcomes.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.