Clinical aspects of normal aging

doi:10.1017/CBO9780511544873.026

25 - Clinical aspects of normal aging

from Normal aging

Published online by Cambridge University Press: 04 August 2010

Anthony E. Lang and

M. Flint Beal: Affiliation:
Cornell University, New York
Anthony E. Lang: Affiliation:
University of Toronto
Albert C. Ludolph: Affiliation:
Universität Ulm, Germany
Marilyn S. Albert: Affiliation:
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA

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Summary

Overview

It is now widely understood that the number of persons living into old age increased dramatically during the last century. In 1900, the average life expectancy at birth was 47 years. By 1950, this had increased to 68 years. In the year 2000, the average life expectancy for males was estimated at slightly over 74 years, and for females it was almost 80 years of age. There is thus increasing interest in understanding the normal changes that occur with age. Along with this has come an interest in developing ways to maintain function at its maximum. This chapter will describe epidemiological aspects of aging, cognitive and motor changes that are associated with aging, the underlying neurobiologic alterations that are thought to be responsible for age-related changes in cognitive and motor function, and the implications of these alterations for the clinical evaluation of an older person.

Epidemiologic aspects of aging

The numbers of persons living to an old age has risen dramatically, and this is expected to continue until at least 2050, as noted above. During the first half of the twentieth century, the increase in life expectancy was largely the result of decreased mortality early in life. The continued expansion of life expectancy during the last half of the twentieth century was largely the result of increased survival during middle and old age. At the same time, virtually all developed countries experienced decreases in the birth rate.

Type: Chapter
Information: Neurodegenerative Diseases
Neurobiology, Pathogenesis and Therapeutics
, pp. 383 - 395

DOI: https://doi.org/10.1017/CBO9780511544873.026 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2005

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