occurrence of amyotrophic lateral sclerosis among iran-iraq war veterans

abstract   background: amyotrophic lateral sclerosis (als) is a progressive neurological disorder with high mortality and morbidity. some risk factors have been implicated for als such as exposure to high magnetic fields, and trace elements like selenium, cadmium and lead. afew studies have been carried out throughout the world to evaluate the prevalence of als among veterans. this study was aimed to evaluate als frequency among iran – iraq war veterans.   methods: medical records of 52580 veterans were studied and those with suspected neuromuscular disorders were referred to a blind neurologist. als was verified according to world federation of neurology criteria. student t-test and chi-square test were used for analysis and a p value less than 0.01 was considered significant.   results: eleven definite als and two possible als cases were identified among the subjects. the mean age of onset of the disease was 43.7±9.7 years. all subjects had a record of at least three months involvement in action and symptoms began to show up after 16.5±3.6 years. the mean interval between exhibition of symptoms and the definitive diagnosis of the disease was 16.5 months.   conclusion: the prevalence of als in our population was significantly greater than that of international surveys (p< 0.01). the onset of the disease occurred at a significantly lower age than typical als (p< 0.01). military service might therefore be a risk factor for als.