Objectives: To review the work pertaining to rheumatoid arthritis (RA)
morbidity in Finland and to compare the data with that available from
other countries. Methods: Extensive investigations in Finland of the
epidemiology of RA, based on nationwide registers designed primarily f
or administrative purposes and on extensive population studies, freque
ntly in combination. Results: According to several surveys with somewh
at different study designs, the prevalence of clinically significant R
A is about 0.8% of the adult Finnish population. Five national health
interviews from a 30-year period have revealed figures about 50% highe
r, but with no clear change in prevalence. The incidence of clinically
significant RA is about 40 per 100,000 of the adult population, which
is in accordance with the prevalence figures. The mean age at diagnos
is increased by 7.6 years from 1975 to 1990. Between 1978 and 1980, 5.
8% of the severe disability in the adult Finnish population was attrib
utable to RA. Some evidence suggests that severe disability resulting
from RA diminished during the 1980s, possibly because of joint replace
ment surgery. Conclusions: Monitoring sickness insurance statistics is
a useful means of following the epidemiology of RA. Copyright (C) 199
8 by W.B. Saunders Company.