A patient's fitness rather than their age should be the key factor in deciding whether they have an operation, according to research.

The study revealed unfit patients cost the NHS an extra £6000 on average after an operation, due to longer recovery times.

Medics have traditionally seen age as a main risk factor for surgical survival and complications, with older people perceived to come out worse, but researchers from Newcastle University and Newcastle Hospitals NHS Foundation Trust have found being physically fit is a more important factor. Fit older people had a lower risk of dying, recovered better after surgery and had a shorter stay in hospital than unfit younger people, they found.