The emerging research consensus is that ageing is driven by several different interacting processes.11,12 These interlinked pathways influence the diseases of ageing in such a way that finding the right lever could likely defeat multiple causes of morbidity.
In the longer term, researchers aim to re-appraise the fundamental process and its mechanics. Recent evidence suggests that the fundamental upper limit for human age is around 120,13 but the question of what determines this; why it differs from other species, and whether drugs modify it remain open. Trials are currently illuminating some ageing mechanisms. Among those mechanisms are age-related dysregulation of metabolism, age-related disruption of adult stem cell function and an age-related increase in the number of senescent cells, which among other events drives an increase in chronic inflammation. Multi-morbidity studies are now planned to test whether alteration of a single pathway, such as metabolism or cell senescence, can ameliorate or prevent multiple diseases of age. This vision for geroscience goes far beyond treating old people: recent research suggests that the same pathways are involved in a variety of conditions, for example pre-eclampsia, accelerated ageing after childhood cancer treatment and radiation effects in space.