Background: Because little is known about the relationship between physical fitness and mortality among very elderly people, we evaluated this association in a Japanese population of 80-year-old community residents.
Methods: Among 1282 80-year-old residents of Fukuoka Prefecture, Japan, 697 individuals (277 men and 420 women) underwent physical fitness tests of handgrip strength, isometric leg extensor strength, isokinetic leg extensor power, stepping rate, and one-leg standing time. Four years later, the dates and causes of death among the participants during those years were analyzed based on data from resident registration cards and from official death certificates.
Results: During the 4-year follow-up period, 107 individuals (58 men and 49 women) died. Of these deaths, 27 were due to cardiovascular disease (CVD), 27 to cancer, 22 to pneumonia, and the rest to other causes. The relative hazard ratios (HR) for all-cause mortality, adjusted for various confounding factors, fell with increases in stepping rate, and the HR for pneumonia mortality fell with increases in leg extensor strength. In contrast, there was no association between cardiovascular or cancer mortality and physical fitness.
Conclusions: A partial association was found between impaired physical fitness at the age of 80 years and increased mortality in the 4 years thereafter. Mortality due to all causes was related only to stepping rate, and mortality due to pneumonia was related to leg extensor strength. Mortality due to CVDs or cancers was not associated with physical fitness.