Prevalence and demographic profile of keratoconus among high school students in Kenya

To determine the prevalence and demographic profile of keratoconus (KC) among high school students in Nairobi County, Kenya.

In this population-based, prospective, cross-sectional study, multistage cluster sampling was used to select the participants. All students underwent visual acuity measurement, auto-refraction, retinoscopy and corneal topography. Students with a scissors reflex on retinoscopy or corneal topography patterns suspicious of KC were referred for corneal tomography.

A total of 3051 students from 29 schools, with a mean age of 17.4 ± 1.6 years (range: 13-25 years) were screened. The prevalence of KC was 1.7% (n = 51) (95% CI, 1.2-2.2) and of KC suspects was 3.8% (n = 117) (95% CI, 3.2-4.6). There were no significant associations between the prevalence of KC and gender, age or ethnicity (all p > 0.05). In the KC group, 88.2% (n = 45) were unaware of their condition, 52.9% (n = 27) were treated for allergic conjunctivitis, 45.1% (n = 23) required spectacles, 11.8% (n = 6) were recommended contact lenses in at least one eye and 49.0% (n = 25) were recommended corneal cross-linking.

Among adolescents, the results of this study indicate a higher prevalence of KC compared to that reported in South Korea, Norway, Brazil and Caucasians in New Zealand, but less than that reported in some countries in the Middle East. Given the high prevalence revealed in this study, a national school screening program and clinical guidelines for screening, diagnosis and management of KC is recommended.