Impacts of Aging


Lead Author(s): 

Jonathan S. Kirschner, MD, RMSK
Se Won Lee, MD

Supporting Author(s): 

Sylvia I. Watkins-Castillo, PhD

Incidence rates of ALS increase with age, peaking between 70 and 80 years. Amyotrophic lateral sclerosis is a fatal condition for most patients with mean life expectancy of about 3 years after diagnosis, although some patients live longer.

Poliomyelitis is a viral infection affecting the nervous system which causes motor neuron disease. Although it has been eradicated by vaccines developed in the 1950's, polio survivors can suffer from post-polio syndrome for several decades (mean of 36 years) with gradual weakness, fatigue and muscle wasting. A study published in 1994-1995 estimated there were about 1 million polio survivors in the U.S., with 443,000 reported having had paralytic polio. Considering 25 to 40 percent of polio survivors develop the post-polio syndrome, it is one of most prevalent motor neuron disease in the elderly population.1


  • Fourth Edition

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