Abstract
Purpose To determine risk factors that affect nonproliferative diabetic retinopathy (NPDR) progression and establish a predictive model to estimate the probability of and time to progression in NPDR. Patients and Methods. Charts of diabetic patients who received an initial eye exam between 2010 and 2017 at our county hospital were included. Patients with proliferative diabetic retinopathy (PDR), fewer than 2 years of follow-up, or fewer than 3 clinic visits were excluded. Demographics and baseline systemic and ocular characteristics were recorded. Follow-up mean annual HbA1c and blood pressure, best-corrected visual acuity, and the number of antivascular endothelial growth factor treatments were recorded. Stage and date of progression were recorded. A 5-state nonhomogeneous continuous-time Markov chain with a backward elimination model was used to identify risk factors and estimate their effects on progression. Results Two hundred thirty patients were included. Initially, 65 eyes (28.3%) had no retinopathy; 73 (31.7%) mild NPDR; 60 (26.1%) moderate NPDR; and 32 (13.9%) severe NPDR. Patients were followed for a mean of 5.8 years (±2.0 years; range 2.1–9.4 years). 164 (71.3%) eyes progressed during the follow-up. Time-independent risk factors affecting progression rate were age (hazard ratio (HR) = 0.99, P=0.047), duration of diabetes (HR = 1.02, P=0.018), and Hispanic ethnicity (HR = 1.31, P=0.068). Mean sojourn times at mean age, duration of diabetes, and annual HbA1c for a non-Hispanic patient were estimated to be 3.03 (±0.97), 4.63 (±1.21), 6.18 (±1.45), and 4.85 (±1.25) years for no retinopathy, mild NPDR, moderate NPDR, and severe NPDR, respectively. Each 1% increase in HbA1c annually diminished sojourn times by 15%, 10%, 7%, and 10% for no retinopathy, mild NPDR, moderate NPDR, and severe NPDR, respectively. Conclusion HbA1c level is a significant modifiable risk factor in controlling the progression of DR. The proposed model could be used to predict the time and rate of progression based on an individual's risk factors. A prospective multicenter study should be conducted to further validate our model.
Highlights
Diabetic retinopathy (DR) is the leading cause of blindness in the United States [1]
There was no difference in the mean age among the DR stages (P 0.067 using one-way analysis of variance (ANOVA)), the patients with no retinopathy were significantly older than the patients with severe retinopathy by Duncan’s multiple comparison analysis
Our study creates a model based on age at the initial visit, annual hemoglobin A1c (HbA1c), and ethnicity to predict the rate of progression time through each Early Treatment Diabetic Retinopathy Study (ETDRS) stage. is may influence clinical care by better predicting the required intervals for evaluating for change and, the required frequency of office visits
Summary
Diabetic retinopathy (DR) is the leading cause of blindness in the United States [1]. Vision loss in DR is often due to diabetic macular edema [2], abnormal blood vessel growth, or retinal scarring [3, 4]. E 3 NPDR stages have varying degrees of vascular permeability, capillary occlusion, and retinal vasculature abnormalities, in the form of microaneurysms, hemorrhages, hard exudates, cotton wool spots, and venous beading [6]. Patients who have PDR can experience severe vision impairment when abnormal vessels bleed into the Journal of Ophthalmology vitreous or when tractional retinal detachment occurs from fibrous scarring [3, 4]. Minimizing vision loss by preventing the progression of DR could save vision in diabetic patients
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
