An increase in the incidence of multiple sclerosis in western Norway.
In the county of Hordaland, Western Norway, the prevalence of MS has been shown to have increased from 20/100,000 in 1963 to 60/100,000 in 1983. This study shows that the increase in prevalence was caused by a highly significant and marked increase in incidence over a 30-year period. The average annual incidence of about 2 per 100,000 population in 1953-1962 increased to 4 per 100,000 in the period 1968-1977. The rise in incidence was parallel for both sexes until 1970. In the last 10 years, the incidence has continued to increase among females, whereas a decrease has been observed among males.
D000328:Adult; D000367:Age Factors; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000453:epidemiology*; D009664:Norway; D012737:Sex Factors