Multiple sclerosis incidence in the Faroe Islands 1986–2007

Objective – Epidemiological studies of the isolated Faroese population
in 1945 identified a high annual incidence of multiple sclerosis (MS) of
10 ⁄ 100,000. At the time, there was speculation that the disease was
brought to the country by British occupation forces resident in the
islands from 1940 to 1945. The objective of the current study is to
determine the incidence of diagnosis of MS in the Faroe Islands during
the period 1986–2007. Methods – All patients in the Faroe Islands
diagnosed with MS from July 1, 1986 to July 1, 2007 are documented
in the current longitudinal, prospective study. The diagnosis is based
on clinical observation, magnetic resonance imaging scanning,
cerebrospinal fluid tests, and visual evoked potential response
testing. Results – The incidence of MS during the period 1986–2007
is 4.5 ⁄ 100,000 annually. This is generally of the same order of
magnitude as other research findings in Scandinavia and Iceland. The
incidence of MS from 1986 to 2007 is about double the incidence in the
Faroe Islands for the period from 1940 to 1986, calculated to be
2.7 ⁄ 100,000 annually. Conclusion – The observed incidence of MS in
the Faroe Islands, where the population is genetically homogeneous
and where the diet exposes the population to neuro-toxic
contamination, is at the same level as found in other high-risk regions.
The former detected epidemics of MS in Faroe Islands seems
apparently to have leveled out and could not be recognized in the
recent period covered by the present survey.