Clinical characteristics and survival pattern of 1,153 patients with amyotrophic lateral sclerosis: experience over 30 years from India.

Amyotrophic Lateral Sclerosis is a progressive disease causing degeneration of upper and lower motor neurons with an average survival of 2 to 3 years. We retrospectively analyzed 1,153 patients of classical sporadic ALS seen over 30 years for the clinical manifestations and survival pattern. There were 855 (74.2%) men and 298 (25.8%) women with a M:F ratio of 3:1. The mean age of onset was 46.2+/-14.1 years (18-85) and the mean duration of illness at evaluation was 17.7+/-20.7 months (0.5-180). Mean age of onset for bulbar onset group was 52.8+/-11.6 and for limb onset was 43.7+/-14.1 (p<0.0001). One third of patients had onset before 40 years of age. The overall median survival duration (MSD) was 114.8+/-25.9(SE) months (3.3-194.4). Survival did not differ between the men [101.7+/-27.4(SE)] and women [118.9+/-6.3(SE)]. Information on death was available in 124 patients. The mean age at death was 52.95 years (25.7-82.6). The MSD for bulbar onset group was 55.9+/-2.9(SE) months and for limb onset group 177.9+/-3.2(SE) (p<0.0001). Gender did not have an effect on the survival period. The clinical manifestations are similar to findings from other developing countries with regards to age of onset, sex ratio and survival. When compared to studies among Caucasians the age of onset was one to two decades earlier and the male preponderance was more. The survival pattern is close to those reported from developing countries particularly from Africa and among Asian immigrants to the West, while it is significantly longer compared to Caucasians who generally have a dismal prognosis. Thus, Indians appear to have a relatively younger age of onset and prolonged survival suggesting the relatively slow course of ALS among Indian patients.