Physical performance and 10-year mortality in a 70-year-old community-dwelling population

Abstract

Poor physical performance is known to be inversely related to mortality. The purpose of the present study was to determine whether an association between physical performance and 10-year mortality could be extended to a Japanese 70-year-old community-dwelling population, and to compare findings with those found in an octogenarian population. Seventy-year-old subjects residing in Niigata city, Japan, participated. Baseline examinations, including a physical performance test of four tests of muscle strength, one test of balance, and one test of agility, were carried out in June 1998 for 600 participants, and these individuals were then followed for 10 years. During the 10-year follow up, 80 subjects died. Cox regression analysis with adjustment for confounding factors showed that high scores in muscle strength tests for lower extremities, such as single-leg and double-leg extensor strength and isokinetic leg extensor power, were found to be related to decreases in total cause mortality. In an elderly 70-year-old Japanese community-dwelling population, poor muscle strength was found to be an independent predictor of total mortality. Together with our previous findings in an 80-year-old population, the association between poor strength and high mortality may have effects at 70 but not 80 years of age.