Multiple sclerosis in Iceland

Abstract

Since 1974 we have attempted to ascertain all cases of MS beginning 1900-1975 in Iceland. As of October 1979 they numbered 168; all but 5 met all diagnostic criteria of the Schumacher Committee. Virtually all cases had been examined by a least one of the authors. Cases were few and sporadic from 1900 to 1922, then increased to a plateau for 1923-44, then again increased in 1945 with an irregular plateau thereafter. Average annual incidence rate for 1945-1954 was 3.2 per 100,000 population, significantly higher than the 1.6 for 1923-1944 or the 1.9 for 1955-1974. Age at onset was significantly decreased for cases with onset 1945-1949 and then sharply increased for those with 1950-1954 onsets. The occurrence of MS in 1945-1954 meets the criteria for a point-source epidemic, whose tail thereafter mérged into what may be "baseline" for Iceland. This postwar epidemic is then similar to that recently described for the Faroe Islands, a land that shares its history, culture, and peoples with Iceland.

Multiple sclerosis

“…Studies in twins (6-10, 12, 13) and conjugal pairs (73) indicate that much of this familial clustering is the result of shared genetic risk factors, while studies of migrants (74) and apparent epidemics (75) indicate a clear role for environmental factors. Detailed population-based studies of familial recurrence risk (76)(77)(78) have provided estimates for familial clustering with λs, the ratio of the risk of disease in the siblings of an affected individual compared with the general population equal to approximately 20-40 (79, 80).…”

Demographic and Clinical Features of Hospitalized Multiple Sclerosis Patients Undergoing a Rehabilitation Program at our Clinic

“…This scale is the best measure of indicating neurological changes in MS patients. In this scale, there are 20 steps, in which half steps are used between 0 (no insufficiency) and 10 (mortality associated with MS) (12). According to the EDSS results that were applied to the patients, EDSS=0 is a normal neurological state, EDSS=0-4 is mild disability, EDSS=4.5-5.5 is moderate disability, and EDSS≥6.0 was grouped as severe disability (13).…”

Strategies for the identification of loci responsible for the pathogenesis of multiple sclerosis

“…EAE can be induced in animal species including rats, mice, guinea pigs, rabbits, marmosets, macaques and rhesus monkeys [1][2][3][4][5][6][7][8][9]. Studies suggest that there are both environmental and genetic risk factors contributing to the pathogenesis of MS [10,11]. Like other autoimmune diseases, MS is complex, with no pattern of inheritance, and is characterized by a process of demyelination and degeneration of the spinal cord, whose initiation is usually attributed to environmental factors.…”

“…There is a relevant mouse model of EAE that is induced with a murine picornavirus called Theiler's virus [12,15]. It has been observed, however, that fraternal twins and siblings of MS patients have approximately 150-300 times greater risk and siblings have approximately 20-40 times higher risk to develop the disease, than unrelated individuals in the population [10,11,16]. This indicates that there is also a genetic component of the disease.…”