Clinical and laboratory factors associated with the severity of proliferative sickle cell retinopathy in patients with sickle cell hemoglobin C (SC) and homozygous sickle cell (SS) disease

Proliferative sickle cell retinopathy (PSCR) is the most frequent vision-threatening complication of sickle cell disease (SCD). We investigated the relationship between the severity of sickle cell retinopathy in heterozygous (SC) or homozygous (SS) adult SCD patients and the clinical and laboratory data obtained during visits to a national SCD referral center. This retrospective longitudinal analysis included 942 SCD patients (313 patients with SC and 629 with SS disease) with ophthalmologic evaluations who were followed over a 19-year period by a multidisciplinary team in a referral center. PSCR was graded using the Goldberg classification. We identified patient and SCD characteristics associated with sickle cell retinopathy severity using multinomial logistic-regression models. Multivariate analysis associated severe PSCR forms (stages III-V) with older age (p=0.032), pulmonary involvement (documented pulmonary hypertension with pulmonary arterial pressure≥40 mm Hg, restrictive syndrome>20%, or previous history of pulmonary embolism diagnosed by vascular imaging) (p=0.029), deafness or tinnitus (p=0.026), and no history of osteomyelitis (p=0.013) for SC patients; and with older age (p<0.001), male sex (p=0.003), and acute pyelonephritis (p=0.04) for SS patients. The model of severe PSCR versus no PSCR showed good calibration and discrimination for SC and SS patients. Awareness of the clinical and laboratory factors significantly associated with severe PSCR in patients with SC or SS SCD may contribute to improved preventive strategies.