Epidemiology of amyotrophic lateral sclerosis in Isfahan, Iran
Background: Few studies are carried out on the epidemiology of amyotrophic lateral sclerosis (ALS) in Middle East with no reports from Iran. Objective: To determine the epidemiological and clinical features of ALS amongst the Iranian population living in Isfahan, Iran. Methods: Medical records of all hospitals with a neurology department and outpatient neurology clinics in Isfahan province from 2002 to 2006 were reviewed, and all patients with the diagnosis of ALS according to El Escorial diagnostic criteria were extracted and related demographic and clinical data were gathered and analyzed. Results: We found 98 new patients (66 men and 32 women) with definite, probable, or possible ALS. The average annual incidence was 0.42/100 000, with the highest incidence rate amongst those aged 70-74. On 21 March 2006, the crude prevalence was 1.57/100 000. Median survival from onset was 48 months (95% confidence interval 34-61) and survival rates for 1, 3,and 5 years after the onset were 94%, 66%, and 32%, respectively. Conclusions: The incidence and prevalence of ALS in the Iranian population seems to be lower compared to other populations and the survival of patients was longer than previously reported.