The Epidemiology And Demography Of Keratoconus In Israel - A 20 Year Population Based Study

Keratoconus is a multifactorial corneal disease which both genetic and environmental factors play a role in its pathogenesis. Studies have shown that the incidence of keratoconus varies between countries and might be influenced by demographical and epidemiological factors. In this study we will determine the effect of these factors on the incidence of keratoconus among the Israeli population.

A population based, retrospective observational cohort study, using the electronic database from the largest public health service organizations in Israel, “Clalit Health Services”.

Medical files of over 2 million Israeli adults from “Clalit Health Services” electronic database between the years 2001-2021 were searched and keratoconus patients were identified. The incidence of keratoconus was calculated for every year and in total, and the effect of age, gender, socio-economic status (SES), and ethnic group were analyzed.

17,403 patients with keratoconus were identified over 20 years and the average incidence was 28.4 to 100,000. The average age of diagnosis was 35.19±13.3 years and the median 31.74 years. The average incidence among males and females were 33.78 and 26.93 to 100,000 respectively (p=0.0001). The average incidence among Israeli Jews and Arabs, were 24.12 and 41.43 to 100,000 respectively (p=0.0001). The average incidence in the low, medium and high SES groups were 30.28, 25.07 and 28.63 to 100,000 respectively and the differences between the low-medium, medium-high and low-high groups were all significant (p=0.0001, p=0.0001 and p=0.008, respectively).

The incidence of keratoconus in Israel is high when compared to other population based studies while the age of diagnosis in Israel is consistent. The incidence among Israeli males in is higher, and Arabs in Israel are at higher risk of developing keratoconus according to our findings. Medium SES was found to be a protective factor against keratoconus since both high and low SES groups showed higher incidence rate. These findings will help us make an earlier diagnosis of keratoconus in high-incidence areas and hopefully improve the prognosis of those patients.