Characteristics and management of postpolio syndrome.

POSTPOLIO SYNDROME (PPS) REFERS to new, late manifestations occurring many years after acute poliomyelitis infection. Over the last 25 years, PPS has become a relatively common problem encountered by primary care physicians. A 1987 National Health Interview Survey estimated that about half of the 640000 survivors of paralytic poliomyelitis in the United States hadnewlatemanifestationsofPPS. Subsequent studies in the 1990s have found the occurrence of PPS among patients withpreviouspoliomyelitis torangefrom 28.5%to64%. Theaveragetimeinvarious reports from the acute poliomyelitisuntil theonsetofPPSisabout35years, with a range from 8 to 71 years. However, it isunclear if theoccurrenceofPPS increases with aging, which may be the case based on the most accepted etiologic hypothesis. The large number of PPS cases presently being seen is probably due to the poliomyelitis epidemics of the 1940s and 1950s. Risk factors for the development of PPS include the severity of the acute poliomyelitic paralysis, age at onset of the acute poliomyelitis (higher risk with adolescent and adult onset), the amount of recovery, and greater physical activity during the intervening years. The course of PPS has been reported to have an average progression based on strength measurements of 1% to 2% per year. Despite the fact that the course is relatively slow, PPS can present with multiple symptoms and signs.