Abstract
Purpose :
To longitudinally examine the transitions in diabetic retinopathy (DR) severity over time and determine which state deteriorates rapidly in an Asian population with diabetes.
Methods :
We analysed 20453 clinic visits by 9481 Chinese, Malay and Indian adults diagnosed with diabetes who attended the annual DR screening visits in primary care clinics as part of the Singapore Integrated Diabetic Retinopathy Screening (SiDRP) programme from 2010-2015 and linked to death data at Ministry of Health. DR was assessed from retinal photographs and graded for severity by professional graders. We applied a multistate Markov model to estimate the annual transition probabilities between states (none, mild, moderate and severe/proliferative DR and the absorbing state, death), and the expected waiting time in each state (sojourn time) adjusted for risk factors including age, sex, systolic blood pressure (SBP), duration of diabetes, HbA1c, and body mass index (BMI).
Results :
The median time between assessments was 12 months, and the majority of patients had at least 3 assessments. The annual transition probability from none-to-mild, mild-to-moderate and moderate-to- severe in the adjusted model were 6.1%, 7.0% and 19.1% and of death from each state were 1.2%, 2%, 19.1%, and 29.8%; mean time spent in each state (sojourn time) were 8.2, 0.8, 0.8 and 2.2 years. While 0.1% progressed from none-to-severe DR, 1.9% progressed from mild-to-severe DR; Probability of regression from mild-to-none, moderate-to-mild and severe-to-moderate DR were: 55.4%, 17.1% and 4.3%. While 12.4% regressed from moderate-to-none, 0.4% regressed from severe DR-to-none. Higher levels of HbA1c and SBP were associated with progression of none-mild and mild-moderate DR and duration of diabetes with no-mild and moderate to severe/proliferative DR. Lower levels of HbA1c were associated with regression from mild-to-none and moderate-to-mild; higher BMI with mild-to-none DR.
Conclusions :
Our results suggest that the mean time to develop mild DR was long (~8 years), while transitions from mild or moderate states were faster within a year. Moderate/above DR greatly increases the probability of progression and death as compared to mild DR/below. HbA1c was associated with both progression as well as regression.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.