Epidemiological evaluation of colonic diverticulosis and dietary fiber in Japan.
The incidence of colonic diverticulosis was examined in 5 hospitals geographically isolated from each other in Japan during the period between mid '70s and 1986. The incidence rapidly increased in all hospitals from 3.5-9.0% in mid '70s and 8.4-23.2% in 1986. The ratio of right-sided type colonic diverticulosis was approximately 70-80% in each hospital and the ratio did not fluctuate significantly during the period. Birth cohort analysis revealed that although the incidence of right-sided diverticula had increased with aging, in groups born in more recent decades right-sided diverticula appeared in younger age than other groups. It was suggested that environmental factors rather than congenital factors may cause the increase of the incidence of right-sided colon diverticula.
Munakata
A
A
First Department of Internal Medicine, Hirosaki University School of Medicine, Japan.
Nakaji
S
S
Takami
H
H
Nakajima
H
H
Iwane
S
S
Tuchida
S
S
D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D004043:Dietary Fiber; D004241:Diverticulum, Colon / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged