Race And Visual Impairment In Patients With Keratoconus At Time Of Diagnosis

Keratoconus is a progressive, bilateral disease that causes thinning of the cornea, leading to irregular astigmatism and significant visual impairment (VI). Prior studies have shown racial and ethnic variation in the progression of keratoconus globally across international cohorts. While disparities in progression of keratoconus have already been studied, disparities in the initial presentation of disease at the time of diagnosis have not been thoroughly investigated. This study evaluated the association between race and disease severity at time of diagnosis.

Wilmer Eye Institute, Johns Hopkins School of Medicine

A retrospective analysis of 2,824 patients with keratoconus seen at Johns Hopkins between 2013 and 2020 extracted patient age, sex, race, tobacco use, family history of keratoconus, insurance, area of deprivation index (ADI), contacts/glasses use, and visual acuity (VA) from electronic health records (EHR) for the first encounter with a keratoconus diagnosis. VI was defined as best available visual acuity of 20/40 or worse with or without correction. VI was analyzed using logistic regression, adjusting for the covariates above.

Adjusted analysis showed higher risk of VI for Black patients compared to White patients (OR 1.63, 95%CI 1.21-2.19, p<0.001). Non-private insurances Medicare (OR 2.02, 95%CI 1.27-3.22, p=0.003) and Medicaid (OR 2.68, 95%CI 1.79-4.00, p<0.001) were associated with increased odds of VI compared to private insurance. Furthermore, lack of correction method had increased risk of VI compared to contact lens use (OR 3.24, 95%CI 2.32-4.54, p<0.001). Lastly, ADI was associated with VI (OR 1.01 per ADI point, 95%CI 1.00-1.01, p=0.007). Current smoking of tobacco or any history of smoking, female sex, atopy, and family history of keratoconus were not associated with increased odds of VI.

VI at presentation was associated with Black race, non-private insurance, ADI, and lack of contacts/glasses use. Black race was associated with VI after adjusting for age, insurance, and ADI, and other covariates, suggesting Black patients have more severe disease at presentation. Our study is an important first step in assessing factors associated with keratoconus severity at presentation and may support developing screening programs for at-risk populations to allow for intervention with crosslinking to prevent visual disability.