Danish Multiple Sclerosis Registry Research Articles

Multiple sclerosis as a retroviral disease? Epidemiological considerations in relation to HTLV-I epidemiology.

The intrafamilial epidemiology of multiple sclerosis was compared with the known intrafamilial epidemiology of infections with HTLV-I. Infections with this retrovirus most often have a subclinical course, but can cause leukemia or a neurological disease resembling multiple sclerosis. Through the Danish Multiple Sclerosis Registry, information was obtained on 79 parent-child cases of multiple sclerosis, and in 55 cases further information was obtained through questionnaires. The study did not reveal any common intrafamilial pattern of MS and HTLV-I infections. It can be concluded that if multiple sclerosis is associated with a specific 'MS virus', it is hardly one with the same epidemiology as HTLV-I, maybe because MS could be a multifactorial disease only developing if various factors coincide in the same person.

Epidemiology of multiple sclerosis: incidence and prevalence rates in Denmark 1948-64 based on the Danish Multiple Sclerosis Registry.

The Danish Multiple Sclerosis Registry (DMSR) is a national register based upon the ethnically homogeneous Danish population of about 5 millions. The DMSR was founded in 1956 following a nationwide Danish prevalence survey of MS in 1949 and a continuous registration of incident cases of MS since January 1, 1948. Included in DMSR are all Danish cases of MS (or suspicion of MS) diagnosed by a neurologist or a department of neurology. The sources of notification are the 22 neurological departments in Denmark, the National Patient Registry, the neuropathological departments, the Registry of Causes of Death, and, up to 1975, the Disablement Insurance Court. Notified cases which do not comply with the standardized diagnostic criteria of the DMSR are excluded. An estimate of the completeness of the DMSR is 90-95% and the validity is around 94%. Age- and sex-specific incidence rates of MS for the interval 1948-64 are presented. The crude annual incidence rate of MS in Denmark was in the year 1948-64 4.42 per 100,000 population, 22% higher in females than males. There was a significant geographical variation of incidence rates and a significant downward trend in incidence rates during the interval, whereas the prevalence rates showed a slight increase.