Assessing the prevalence of sickle cell retinopathy in clinical practice

Abstract Sickle cell retinopathy (SCR) is a common, vision-threatening complication of sickle cell disease (SCD), yet adherence to national eye screening guidelines remains unacceptably low. Barriers such as transportation, cost, and limited awareness among both patients and providers contribute to underdiagnosis. One survey found that more than half of adults with SCD were unaware of their risk for ocular complications. While recent larger studies have reported higher rates of SCR, these are likely underestimates since many individuals with SCD do not receive consistent eye exams. SCR prevalence also differs by genotype, with certain subtypes, like HbSC, having higher rates. Without routine screening, the true burden of SCR remains unclear, limiting available data for clinical guidelines and resource planning. Real-world data across genotypes are needed to inform screening strategies to ensure timely detection and management to prevent avoidable vision loss. The study's objective was to assess the observed prevalence of SCR among screened patients with SCD and quantify the degree of under-screening in a real-world clinical setting. This was a retrospective observational study of 312 patients with SCD across three clinical sites in Georgia (Augusta, Macon, and Sylvester) from 2021–2024. There were 143 patients from Augusta, 77 from Macon and 92 from Sylvester. Data were stratified by genotype and location. SCR prevalence was assessed both among the full SCD population and only those who received an eye exam during the study period. Primary outcomes included (1) the proportion of patients who received an eye exam and (2) the observed prevalence of SCR among those screened. Secondary measures included genotype-stratified detection rates and geographic variation in screening practices. Of 312 patients with SCD, only 108 (35%) underwent a screening eye exam within the set timeframe. Among those screened, 81 (75.0%) were diagnosed with SCR. When considering the full population, this yields an apparent prevalence of only 25.9%, highlighting how low screening rates may mask the true burden of disease. Screening and detection rates varied by clinical site, with the highest rates observed in Augusta, where 59% were screened and 81% had SCR on exam. Macon had a screening rate of 20% with a SCR rate of 47%, while Sylvester had a screening rate of 9% and a SCR rate of 63%. Genotypic differences were noted. Observed SCR rates were 68% among screened patients with HgbSS and 89% among those with HgbSC. While observed SCR prevalence was high among those screened, most patients with SCD did not receive an eye exam, suggesting that many cases remain undiagnosed. This discrepancy is reflected in Macon and Sylvester's lower SCR detection rates, which coincide with lower screening rates. Assessing the true burden of SCR in modern times with advancing SCD treatments requires updated data and greater education for both patients and providers. Strengthening screening implementation and integration between hematology and ophthalmology are essential to ensure individuals with SCD receive appropriate eye care.