Nationwide incidence of clinically diagnosed central retinal artery occlusion in Korea, 2008 to 2011

Purpose: To define the incidence and demographics of clinically diagnosed central retinal artery occlusion (CRAO) in Korea.

Design: Nationwide population-based retrospective study using data entered into the Korean national health claims database from 2007 to 2011.

Participants: Data of the entire Korean population (N = 47,990,761, based on the 2010 census) were analyzed.

Methods: We used the national health claims database to identify patients diagnosed with CRAO. Incident cases were those with no claims related to CRAO in 2007 and were included once on the earliest claims related to CRAO in the years 2008 to 2011. Incident cases had a disease-free period before diagnosis of at least 1 to 4 years. The average incidence rate of CRAO was estimated according to the entire Korean population.

Main outcome measures: The person-time incidence rates of clinically diagnosed CRAO in Korea, including the age- and sex-specific incidence rates, were estimated.

Results: A total of 3464 CRAO cases (59.1% men) were identified. The incidence rate of clinically diagnosed CRAO during the study period was 1.80 per 100,000 person-years (95% confidence interval [CI], 1.74-1.86). The incidence rate among men and women was 2.15 (95% CI, 2.05-2.24) and 1.47 (95% CI, 1.39-1.54) per 100,000 person-years (male-to-female ratio, 1.47), respectively. The age-specific male-to-female ratios were constant between the ages of 30 and 89 years (range, 1.51-2.10 years). The highest incidence of 10.08 (95% CI, 8.80-11.35) per 100,000 person-years was observed in those aged 80 to 84 years (14.65 [95% CI, 11.90-17.40] and 8.00 [95% CI, 6.63-9.37] per 100,000 person-years for men and women aged 80-84 years, respectively). The incidence rate of CRAO increased exponentially with age until the 9th decade of life.

Conclusions: To our knowledge, this is the first nationwide epidemiologic study of CRAO in individuals of all ages. The incidence rate of CRAO in Korea increased exponentially with increasing age and was highest among those aged 80 to 84 years. Moreover, the incidence rate in men was 1.47 times higher than that in women.