Objective and methods: To characterize the epidemiological features of chronic inflammatory demyelinating polyneuropathy (CIDP) in the Japanese population, we performed a nation-wide assessment of the prevalence and incidence rates in Japan.
Results: The prevalence rate per 100,000 was 1.61 in the total population; 2.01 in males and 1.23 in females. The age-dependent prevalence rate was 0.22 in juveniles (< 15 y.o.), 1.50 in young adults (15 - 55 y.o.) and 2.31 in elderly adults (> 55 y.o.), respectively. The sex- and age-dependent prevalence rate was 0.22 in males and 0.24 in females in juveniles, 1.81 in males and 1.19 in females in young adults, 3.12 in males and 1.64 in females in elderly adults. The annual incidence rate per 100,000 was 0.48 in the total population, 0.58 in males and 0.38 in females. The age-dependent incidence rate was 0.06 in juveniles, 0.40 in young adults and 0.73 in elderly adults, respectively. The sex- and age-dependent incidence rate was 0.05 in males and 0.08 in females in juveniles, 0.50 in males and 0.30 in females in young adults, 0.93 in males and 0.58 in females in elderly adults. Both the prevalence and incidence rates were very similar throughout the eight geographical areas studied, from the northern to the southern parts of Japan.
Conclusions: The prevalence and incidence rates were similar to those reported in the Caucasian population. The pathogenic background is suggested to be common throughout the different races and geographic areas, while gender and age effects should be taken into account in the pathogenesis of CIDP.
- Japanese population
- chronic inflammatory demyelinating polyneuropathy (CIDP)