The prevalence and risk factors of keratoconus: a systematic review and meta-analysis
Mohammadreza Asadollahi1 *, Mehdi Khabazkhoob 2
- Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran
- Department of Medical Surgical Nursing, School of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Abstract: This study was conducted to determine the prevalence and risk factors of keratoconus worldwide
Methods: In this meta-analysis, using a structured search strategy from two sources, four electronic databases (PubMed, Web of Science, Google Scholar, and Scopus) as well as the reference lists of the selected papers were searched from inception to June 2018 with no restrictions and filters. The outcome of the study was the prevalence of keratoconus and its risk factors, including eye rubbing, family history of keratoconus, atopy, allergy, asthma, eczema, diabetes type I and II, and sex.
Results: In this study, 3996 papers were retrieved of which 29 were analyzed. These 29 papers included 7,158,241 participants from 15 countries. The prevalence of keratoconus in the whole population was 1.38 per 1000 population (95% CI: 1.14-1.62 per 1000). The prevalence of keratoconus was 20.6 per 1000 (95% CI: 11.68-28.44 per 1000) in men and 18.33 per 1000 (95% CI: 8.66-28.00 per 1000) in women. The odds ratio of eye rubbing, family history of keratoconus, allergy, asthma, and eczema was 3.09 (95% CI: 2.17-4.00), 6.42 (95% CI: 2.59-10.24), 1.42 (95% CI: 1.06-1.79), 1.94 (95% CI: 1.30-2.58), and 2.95 (95% CI: 1.30-4.59), respectively.
Conclusion: The results of this study, as the most comprehensive meta-analysis of keratoconus prevalence and risk factors, showed that keratoconus had a low prevalence in the world and eye rubbing, family history of keratoconus, allergy, asthma, and eczema were the most important risk factors of keratoconus according to the available evidence.
