Predictive Factors for Progression in Sickle Cell Retinopathy: Longitudinal Evaluation of a United States Cohort

To estimate progression rates in sickle cell retinopathy (SCR) and identify risk factors associated with progression.

Retrospective Cohort Study.

Patients with SCR (317 patients; 620 eyes) seen at the Retina Division of the Wilmer Eye Institute at least once between July 1, 2013 and June 30, 2023.

Demographics and clinical history were retrospectively extracted from electronic medical records. Goldberg staging of SCR was performed using fluorescein angiography or ultra-widefield fundus photography. Cox-proportional hazards models were used to evaluate factors associated with progression.

Progression from baseline nonproliferative sickle retinopathy (NPSR) to proliferative sickle retinopathy (PSR), and from baseline PSR to more advanced PSR.

Progression occurred in 10.7% of baseline NPSR eyes and 17.0% of at-risk baseline PSR eyes (median follow-up, 7.8 and 11.1 years, respectively). Active smoking at PSR diagnosis was significantly associated with progression to more advanced PSR (hazard ratio [95% confidence interval], 2.78 [1.50-5.16]). Age at diagnosis, sex, genotype, hydroxyurea use, blood transfusions, chronic red cell exchanges, bone marrow transplantation, and lifetime smoking history were not associated with SCR progression. Qualitative assessment of macular optical coherence tomography findings did not correlate with baseline peripheral vascular stage and were not associated with SCR progression.

The higher progression rate within the baseline PSR cohort supports early referral and longitudinal ophthalmic surveillance for these patients. The strong association between active smoking at PSR diagnosis and subsequent progression supports recommendations for smoking cessation and closer monitoring with timely intervention among active smokers with PSR.