Abstract
PURPOSE: The current prediction of preclinical diabetic retinopathy (DR) in asymptomatic patients with diabetes mellitus (DM) is limited due to a lack of suitable indicators. This study aimed to identify the predictors of neurodegenerative changes in type 2 DM patients during the preclinical stage of DR using sociodemographic and DM clinical parameters and retinal morphology. METHODS: Fifty-six adult DM participants (mean age: 40.41 ± 7.281 years) were classified into three groups: DM without DR, DM with mild nonproliferative DR (NPDR), and DM with moderate-to-severe NPDR. Demographic data, including age, gender, race, DM duration, glycated hemoglobin levels, household income, comorbidities, and insulin dependency, were collected. Retinal morphology, including macular retinal layer thickness, peripapillary retinal nerve fiber layer, and vascular caliber, were analyzed. Multinomial logistic regression models explored these factors' influence on NPDR prediction. RESULTS: Participants with moderate-to-severe NPDR were less likely to have DM without comorbidities (odds ratio [OR]: 0.048, 95% confidence interval [CI]: 0.003-0.823, P = 0.036). Those with longer DM duration were 27% more likely to develop moderate-to-severe NPDR (OR: 1.272, 95% CI: 1.035-1.564, P = 0.022). Retinal morphology parameters did not predict NPDR risk and severity levels in DM patients, except for mild NPDR, which had a 1.05 times higher risk of wider central retinal arteriolar equivalent (CRAE) (OR: 1.052, 95% CI: 1.002-1.105, P = 0.043). CONCLUSION: DM duration, comorbidity presence, and widened CRAE are critical parameters for assessing neurodegenerative changes in preclinical DR. These parameters could be incorporated into DR screening programs to mitigate NPDR progression and enhance long-term visual outcomes of DM patients.