Physiological aspects of the aging cardiovascular system.

Most putative studies on the physiology of the aging cardiovascular system in humans have been cross-sectional. The results are therefore bedeviled by selective mortality and probably influenced by subclinical disease processes. Even accepting these problems, critical reading of the published literature shows that there is very little substantive evidence for the "well-known" age-related changes in cardiovascular physiology such as baroreflex impairment, sympathetic hyperactivation, adrenoceptor dysfunction, or neurohumoral abnormalities.