Epidemiology and the Estimated Burden of Microbial Keratitis on the Health Care System in Taiwan: A 14-Year Population-Based Study

Purpose: To investigate the epidemiologic characteristics of microbial keratitis and its overall burden on the health care system in Taiwan. Design: Retrospective, population-based study. Methods: We conducted a study using claims data in the Taiwan National Health Insurance Research Database in 2000-2013, employing diagnoses, drugs, and procedure codes to define diseases and procedures. Participants were classified into groups according to the requirement of hospitalization and surgical intervention. The main outcome measures were incidence, risk factors, predictive factors for hospitalization and surgical intervention, and health care expenditure. Results: A total of 2,071 patients were included. The overall incidence significantly increased from 8.4 in 2000 to 20.2 per 100,000 person-years in 2013. The peak age range of incidence was between 18 and 40 years, but the peak age group for health care expenditures was those older than 65 years. A total of 704 patients (33.99%) had analyzable risk factors, of which the top 3 were diabetes mellitus (DM, 11.52%), eye trauma (10.55%), and dry eye (8.72%). Older patients, those using steroid and antiglaucoma agents, and those with ocular and systemic diseases were susceptible to further hospitalization and surgical intervention for the treatment of microbial keratitis. Conclusions: In Taiwan, DM, eye trauma, and dry eye were key predisposing factors for microbial keratitis. Older patients (>40 years) accounted for approximately 80% of health care expenditure for the management of infectious keratitis. Special care may be required for older patients with medication-related risk factors and ocular and systemic comorbidities because they are likely to have severe diseases leading to hospitalization and surgical interventions.