@article {1485, title = {Correlates of performance-based measures of muscle function in the elderly: the Cardiovascular Health Study.}, journal = {J Gerontol A Biol Sci Med Sci}, volume = {52}, year = {1997}, month = {1997 Jul}, pages = {M192-200}, abstract = {

BACKGROUND: It is unknown how much age-related changes in muscle performance represent normal aging versus the effects of chronic disease and life style. We examined the correlates of four performance measures-gait speed, timed chair stands (TCS), grip strength, and maximal inspiratory pressure (MIP)-using baseline data from the Cardiovascular Health Study (CHS), a population-based study of risk factors for heart disease and stroke in persons > or = age 65.

METHODS: We analyzed data from the 5,201 CHS participants. Variables were arranged into nine categories: Personal Characteristics, Anthropometry, Physical Condition, Reported Functional Status, Subjective Health, Psychological Factors, Symptoms, Cognitive Status, Habits and Lifestyle, and Prevalent Disease. Independent correlates were identified using stepwise linear regression.

RESULTS: The regression models explained 17.7-25.4\% of the observed variability. Although age significantly correlated with each measure, it explained little of the variability (< or = 5.7\%). Anthropometric features plus physical condition explained 14.0-17.4\% of the variability for grip strength and MIP, but 2.8-12.9\% of the variability for gait speed and the log of TCS. Subjective health and psychological factors explained 1.8-9.4\% of the variability in gait speed and the log of TCS, but < or = 1.2\% of the variability in grip strength and MIP. Variables for prevalent disease explained < or = 1.3\% of the variability in each measure.

CONCLUSIONS: After age 64, age explained little of the variability in muscle performance in a large sample of mostly functionally intact, community-dwelling older persons. Complex measures such as gait speed were more associated with subjective factors than were direct measures of strength. Prevalent disease contributed surprisingly little to muscle performance.

}, keywords = {Aging, Anthropometry, Cardiovascular Physiological Phenomena, Female, Gait, Hand Strength, Health Status, Humans, Male, Middle Aged, Motor Activity, Muscles, Pressure, Regression Analysis, Respiration}, issn = {1079-5006}, author = {Hirsch, C H and Fried, L P and Harris, T and Fitzpatrick, A and Enright, P and Schulz, R} }