An epidemic-like cluster of motor neuron disease in a Swedish county during the period 1973-1984

Neuroepidemiology. 1996;15(3):142-52. doi: 10.1159/000109901.


We have tried to find all cases of motor neuron disease (MND) with onset during the study period 1961-1990 in the county of Skaraborg, Sweden, and in this retrospective study we have identified 168 cases, 107 men and 61 women. Fifty percent of them were alive 2 years after onset. The number of MND cases in consecutive 5-year intervals during the study period was shown to be statistically significantly elevated for males in the period 1981-1985 (Knox test disjoint procedure, p = 0.02). During the period 1973-1984, 70 males had onset of MND, corresponding to an average annual incidence of 4 per 100,000 person-years. This epidemic-like cluster was compared to the MND morbidity in a neighbouring county and was shown to be statistically significantly elevated even when the p value was adjusted for multiple comparisons. Agricultural work was significantly more common among the cases compared to the rest of the population.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Distribution
  • Aged
  • Aged, 80 and over
  • Agricultural Workers' Diseases / epidemiology
  • Agricultural Workers' Diseases / etiology
  • Confidence Intervals
  • Disease Outbreaks*
  • Female
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Morbidity
  • Motor Neuron Disease / epidemiology*
  • Motor Neuron Disease / etiology
  • Retrospective Studies
  • Sex Distribution
  • Space-Time Clustering
  • Sweden / epidemiology