[Yearly changes and geographical distribution of allergic rhinitis morbidity estimated from records of the national health insurance].
The age-adjusted morbidity of allergic rhinitis (AR) in Ibaraki prefecture in May, estimated from data of national health insurance records, increased remarkably from 1980 to 1992 with varying yearly rates of increase. High AR morbidity years coincided with years of high Japanese cedar and cypress pollen counts, and moreover, an estimate equation of the morbidity using as explanatory variables, year and the yearly total count of pollen, accurately estimated AR morbidity. The AR morbidity varied with the size of the municipality. The AR morbidity of the town group and village group were about 80% and about 60% respectively of the city group in 1992. The map of the AR morbidity of each municipality showed that urbanized districts had higher morbidity than areas with cedar forests, which are supposedly sources of the cedar pollen. Continuous increase of morbidity of districts with much cedar forests terminated in 1986. Since then only the fluctuation of the morbidity corresponding to the pollen count was observed. The ratio of the morbidity of the years with much pollen to that of the years with little pollen was mapped. The map showed good agreement with the map of cedar forests. The results obtained above demonstrate the usefulness of the data of the national health insurance records.
Tamura
K
K
Institute of Community Medicine, University of Tsukuba.
Ono
M
M
Murakami
M
M
Takahashi
H
H
Sairenchi
T
T
Tamiya
N
N
Arai
T
T
D000293:Adolescent; D000328:Adult; D000368:Aged; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008875:Middle Aged; D009313:National Health Programs; D006255:Rhinitis, Allergic, Seasonal / Q000453:epidemiology*