Changes in physical capacity and sensory/psychomotor functions from 75 to 80 years of age and from 80 to 85 years of age--a longitudinal study.

The purpose of the study was to describe the performance of initially 75- and 80-year-old men and women in physical, sensory and psychomotor tests, to analyse longitudinal changes in these measures over a five-year follow-up period, and to ascertain if the performance in these measures is predictive for survival. At baseline, all 75- and 80-year-old men and women living in the town of Jyväskylä (n = 663) were invited to participate in the study. Five years later those who had participated at baseline, survived and were still resident in Jyväskylä (n = 432) were again invited. As expected, a better performance in men than in women was found in tests of maximal walking speed, stair mounting and maximal isometric muscle strength in both age groups. Men also had better performance in psychomotor tests and visual acuity whereas auditory functions and postural balance were on average better in women. In some measures the longitudinal changes in five years were more pronounced than suggested by the cross-sectional comparisons between the 75- and 80-year-olds at baseline (e.g. psychomotor speed). In some others the longitudinal changes were smaller than expected on the basis of the cross-sectional comparisons (e.g. isometric muscle strength). In sensory functions longitudinal changes corresponded well with the results of the cross-sectional comparisons. Poor physical capacity at baseline was a significant predictor of subsequent death during the follow-up among the women but much less among the men. For both sexes a low psychomotor speed at the baseline was indicative of a poor survival. It is concluded that the correspondence of the results obtained in cross-sectional comparisons with longitudinal changes varies from one function to another. This correspondence may also be influenced by mortality which is differentially associated with the physical, sensory and psychomotor functions analysed in the present study.