EPIDEMIOLOGIC AND CLINICAL CHARACTERISTICS OF ALS IN BELGRADE, YUGOSLAVIA

We present the results of the first epidemiological study of ALS in Be lgrade. The distribution of 58 newly discovered cases in a 7-year surv ey period (1985-1991) showed that the average annual age-adjusted inci dence rate was 0.42 per 100,000 population (95% confidence interval, 0 .18-0.83). The rate for males was 1.5 times higher than the rate or fe males. The greatest age-specific average incidence rate was observed i n patients between 60 and 64 (3.66 per 100,000 population; 95% confide nce interval, 2.17-5.78). The actual age-adjusted prevalence rate on D ecember 31, 1991 was 1.07 per 100,000 (95% confidence interval, 0.71-1 .71). The mean age at onset of the disease was 56.2+/-9.8 and it range d from 24 to 74. We studied the natural course of the disease through the mean duration and cumulative probability of survival. The mean dur ation of the disease was 27.7+/-18.2 months. The cumulative probabilit y of survival was 27% for the whole population in a 5-year interval. E lderly patients and those with bulbar signs at onset had a poorer prog nosis. Patients under 49 at onset and those with the spinal form of th e disease survived longer.