Prevalence, Age at Diagnosis, Mortality, and Cause of Death in Retinitis Pigmentosa in Korea-A Nationwide Population-based Study.

PURPOSE: To determine the prevalence and mortality of retinitis pigmentosa (RP) patients in Korea.

DESIGN: Population-based retrospective cohort study.

METHODS: We used data covering the 2011-2014 period from the Rare Intractable Disease (RID) registry and Health Insurance Review and Assessment (HIRA) service, which include information on all patients diagnosed with RP based on predefined diagnostic criteria. Using the HIRA-RID database, we evaluated the prevalence and age at diagnosis of RP patients across the entire Korean population. We further linked the data from Statistics Korea to the HIRA-RID database to confirm mortality and causes of death.

RESULTS: The prevalence in the total population across all ages was 11.09 per 105 people, and the prevalence in those over the age of 40 was 16.16 per 105 people. The age at diagnosis ranged from 0 to 95 and, on average, was 44.8. The standardized mortality ratio (SMR) was 1.56 for all ages, peaking at 2.61 in men aged 40-59, which was attributed to 6.6-fold higher suicide rates than the same age group in the general male population.

CONCLUSIONS: This is the first nationwide epidemiologic study of RP patients covering the entire population of all ages. The results suggest that the prevalence of RP in Korea is about 1 in 9000 for all ages and 1 in 6000 for those over 40 years of age. The higher mortality of RP patients than that of the general population is attributable to a high suicide rate in male RP patients of working ages, which necessitates a careful attention to their mental health.