Introduction

The world faces unprecedented challenges and opportunities from an ageing population. In health care, this is resulting in a transition from the dominance of acute illnesses and infections to that of chronic and degenerative conditions. Clinical recognition of this is hardly new. Hippocrates noted common age-associated medical conditions and Aristotle even offered a theory of ageing based on loss of heat. Remarkably, our current concepts of ageing are also bound up with combustion – cellular respiration. The emergence of old age as the focus of a medical specialty was prompted by the growth of older populations living in urban poverty in Paris1 and, later, New York and London. Now that the expectation of growing old is commonplace in developed countries and is very rapidly spreading worldwide, it is beginning to influence attitudes and behaviour throughout life. In this chapter we address briefly several issues.

1. ■ What is population ageing, and why and how does it occur?

2. ■ The genetics and evolution of ageing — has ageing evolved?

3. ■ What distinguishes ageing from disease?

4. ■ What are the cellular and molecular processes involved with ageing of somatic cells?

5. ■ How do germ cells differ from somatic cells?

6. ■ How does menopause fit in with evolution of ageing?