Prevalence, Mortality, and Cause of Death in Charcot-Marie-Tooth Disease in Korea: A Nationwide, Population-Based Study

Background: Charcot-Marie-Tooth disease (CMT) is a group of clinically and genetically heterogeneous disorders that primarily affect the peripheral nervous system. Epidemiological studies of CMT have not yet been performed in Korea. Objectives: This study was performed to estimate the prevalence of CMT in Korea and the socioeconomic status, mortality, and causes of death of Korean patients with CMT. Methods: Data on patients with CMT were obtained from the rare intractable disease registry and the National Health Insurance Service for the years 2005-2018. Results: During the study period, 2,885 CMT patients were enrolled. The prevalence per 100,000 persons in 2018 was 5.2 (6.1 for men and 4.4 for women), peaking at ages 15-39 years, with almost twice as many men (n = 714) as women (n = 402) in this age group. Of the CMT patients, 226 (7.8%) were receiving medical aid, a public assistance program targeting poor individuals, at the time of diagnosis and 253 (8.8%) at last follow-up or death. From 2005 to 2017, 170 patients died, including 118 men and 52 women. The standardized mortality ratio (SMR) was 1.57 (95% CI 1.34-1.83) for all patients and did not differ in men and women. Age-specific SMR was highest in patients aged under 9 years, gradually declining thereafter. Neurologic disease as a cause of death was significantly more frequent in CMT patients than in the general population. Conclusions: This was the first nationwide epidemiologic study of CMT patients in Korea. This study confirmed the characteristics associated with the prevalence of and mortality from CMT by age and is the first to report the socioeconomic status and causes of death of CMT patients.