Motor Neuron Disease: Epidemiologic Studies

The etiology of motor neuron disease (MND) is unknown and treatment is limited to measures which sustain the patient. We review selected epidemiologic studies searching for a pattern in the clinical expression of MND which may reflect the operation of the underlying cause. Recognition of patterns of occurrence of MND might provide the basis for testable etiologic hypotheses for MND. In addition, recognition of the association of MND with diseases of known cause or the analogy of diseases of known cause with MND may provide further etiologic hypotheses.