MULTIPLE SCLEROSIS and HODGKIN'S DISEASE IN DENMARK

Abstract

Hodgkin''s disease in young adults and multiple sclerosis [MS] may have related causes because the age of clinical onset and the geographic distribution of both are similar. Between 1943-62, the average annual incidence rate for Hodgkin''s disease in Denmark was 2.25/100,000 population (2.68 male and 1.83 female). Between 1951-69, the average annual death rate for Hodgkin''s disease was 2.15/100,000 (2.66 male and 1.64 female). The average annual incidence rate for MS in Denmark was calculated from age at onset for 2481 prevalent cases of 1949, the 1940 population, and an average annual incidence of 128.86 cases for 1939-45: the average annual incidence rate per 100,000 was then 3.35 (3.00 male and 3.69 female). Age specific incidence and death rates for Hodgkin''s disease in Denmark showed bimodal curves, with 1 peak at age 25-29 yr and the other at age 70-74 yr; this was found for both sexes, with male rates consistently higher than female. The age specific incidence rates for MS were clearly unimodal with a peak at age 25-29 yr more definite in females than males. Rates for MS were notably higher for young females than males but about equal by sex for those over the age of 30 yr. The geographic distribution of MS within the counties (amter) of Denmark was markedly non-random, with the major concentration of high prevalence areas across middle Jutland and on to Fyn. Geographic distribution of Hodgkin''s disease, whether for the young or the old, and whether from incident or death cases, showed no significant variation from a homogeneous distribution. In formal testing there was no correlation of any Hodgkin''s distribution with that of MS. A review of the Hodgkin''s data for distribution in the USA, on which the original hypothesis was based, suggests the variation there may be little more than reporting artifact. There is no relation between distributions of these 2 disorders, and the factors they appear to have in common are non-specific or of questionable validity. MS and Hodgkin''s disease, even in the young, do not share a common etiology.