Show Summary Details
Page of

Ageing and clinical medicine 

Ageing and clinical medicine
Ageing and clinical medicine

Claire Steves

, and Neil Pendleton

Page of

PRINTED FROM OXFORD MEDICINE ONLINE ( © Oxford University Press, 2021. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy and Legal Notice).

date: 28 February 2021

In 2017 there were, for the first time, more people older than 65 years than children under the age of 5 years. Despite the recent exponential increase in human lifespan, health-span has not kept pace, and variability between countries in healthy lifespan exceeds that of life expectancy. The increase in morbidity as people age is largely explained by loss of physiological reserve capacity in multiple systems simultaneously, which is termed frailty. Recent evidence suggests that different heritable (intrinsic factors) factors drive the ageing of different organ systems, but diverse systems share environmental (or extrinsic) drivers. Ageing is associated with macromolecular changes (molecular damage); changes in nutrient sensing, metabolism, and metabolic signalling; senescence in stem cells; altered intercellular communication, in particular changes associated with inflammaging; and changes in circadian rhythms and the hypothalamo-pituitary-adrenal axis.

Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.

Please subscribe or login to access full text content.

If you have purchased a print title that contains an access token, please see the token for information about how to register your code.

For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.