Abstract
OBJECTIVE: To define long-term changes in subjective symptoms among polio survivors in Japan. DESIGN: Prospective cohort study. PATIENTS: Sixty-five polio survivors. METHODS: Surveys were conducted on subjective symptoms including muscle weakness and limb atrophy during 2007 and 2021. The results of manual muscle tests of the upper and lower limbs on both sides during 2007 were summed and scored, and the side with lower scores was defined as the poor side. The participants were classified as younger or older groups based on the median age at the first survey (i.e., 58 years old) and the subjective symptoms were compared between the two groups. RESULTS: As a whole, muscle atrophy and weakness progressed in the lower and upper limbs while fatigue was reduced. Muscle weakness progressed especially in the lower limbs on the poor side in the younger group, and in the older group it progressed in the lower limbs on the good side and the upper limbs on the poor side. CONCLUSION: The timing of progressive muscle weakness differed between the upper and lower limbs of younger and older polio survivors.