Tragedy and delight: the ethics of decelerated ageing

Abstract

Biogerontology is sometimes viewed as similar to other forms of biomedical research in that it seeks to understand and treat a pathological process. Yet the prospect of treating ageing is extraordinary in terms of the profound changes to the human condition that would result. Recent advances in biogerontology allow a clearer view of the ethical issues and dilemmas that confront humanity with respect to treating ageing. For example, they imply that organismal senescence is a disease process with a broad spectrum of pathological consequences in late life (causing or exascerbating cardiovascular disease, cancer, neurodegenerative disease and many others). Moreover, in laboratory animals, it is possible to decelerate ageing, extend healthy adulthood and reduce the age-incidence of a broad spectrum of ageing-related diseases. This is accompanied by an overall extension of lifespan, sometimes of a large magnitude. Discussions of the ethics of treating ageing sometimes involve hand-wringing about detrimental consequences (e.g. to society) of marked life extension which, arguably, would be a form of enhancement technology. Yet given the great improvements in health that decelerated ageing could provide, it would seem that the only possible ethical course is to pursue it energetically. Thus, decelerated ageing has an element of tragic inevitability: its benefits to health compel us to pursue it, despite the transformation of human society, and even human nature, that this could entail.

Figure 1.

(a) A piecemeal approach to study diseases of ageing generates treatments that are limited in scope, and which lead to the rapid replacement of one disease by another (e.g. cardiac ischaemia by Alzheimer's disease). (b) A more rational approach to reduce a broad spectrum of age-related diseases would be to treat the underlying cause of all these pathologies: the underlying ageing process. Note that this dichotomous scheme is polemical in character. In fact, recent biomedical studies are increasingly identifying interconnections between late-life pathologies. For example, type 2 diabetes is linked to risk of dementia, driven by vascular disease.

Figure 2.

Decelerated ageing may not change lifetime risk of disease. Risk of, say, cancer is greatly reduced at age A in the treated population. However, risk of cancer may well be the same at age A (grey line, untreated) and age B (black line, treated).