[Nature history of amyotrophic lateral sclerosis].

To explore the nature history of amyotrophic lateral sclerosis (ALS) including type at onset, involvement of region, patterns of spread, survival time and prognosis.A total of 86 patients with sporadic ALS underwent follow-ups at 6-month intervals. Symptom appearances were determined by the revised version ALS functional rating scale. The data were analyzed with Kaplan-Meier curves, t test and variance.Their median survival time was 33 months. Median survival time with combined type onset (combined-type ALS<1) defined as involvement of two regions within 1 month of initial presentation was 12 months; Median survival time with combined type onset (combined-type ALS 2-3) defined as involvement of two regions within 2-3 months from single-site onset was 19 months. The median survival time with combined type onset was shorter than with single-site onset. The interval from onset to involvement of a second region was correlated significantly with survival. ALS frequently involved anatomically close to regions in a longitudinal manner and rarely skipped more distantly in disease progression. Early manifestations of bulbar symptoms within 1 year and appearance of respiratory symptoms in patients with normally preserved motor neuron function were associated with a worse survival. Nine patients surviving >5 years had a lower limb onset with a relatively younger age of onset.The patients with combined type onset, shorter time of interval from onset to involvement of a second region, early involvement of bulbar and respiratory functions are associated with poor prognosis. Lower limb and younger age onset may achieve a better survival.