Gender differences in clinical features at the initial examination of late-onset amyotrophic lateral sclerosis.

BACKGROUND:Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that mainly affects motor neurons in the brain and spinal cord. With the advent of aging societies, the proportion of elderly patients with ALS is expected to increase. METHODS:We retrospectively compared the clinical characteristics at the initial examination of patients with onset of ALS at age 74 years or younger (early onset) and those aged 75 years or older at onset (late-onset) at a single regional ALS diagnostic center in Japan. RESULTS:The phenotype of late-onset ALS differed between males and females, with late-onset females having more bulbar-onset ALS and significantly lower body mass index, late-onset males having more frequent bulbar and respiratory symptoms at the initial examination, and significantly lower forced vital capacity at the initial examination in both groups compared to early onset patients. CONCLUSION:For late-onset patients, maintenance of skeletal muscle mass by early intervention for bulbar and respiratory symptoms may be useful for prolonging survival; however, a prospective analysis is warranted.