Risk factors in motor neuron disease: a case-control study.

A case-control study of risk factors in 512 cases of motor neuron disease (MND) and 512 controls, affected by other neurological diseases, was performed. Clinical history showed a significant increase in gastric ulcer and mechanical injuries among MND cases, whereas the frequencies of operations, poliomyelitis, malignancies and autoimmune diseases were similar for cases and controls. The women affected by MND had a later menarche and an earlier menopause; therefore, the reproductive period was significantly shorter, supporting a possible role of sexual hormones in the pathogenesis of MND. The analysis of occupations showed an increased number of farmers and also of subjects exposed to chemical products among MND cases.