One of the clearest signs of medical and social progress in the post-NHS era is the leap in life expectancy.

Medical advances, better nutrition and living conditions have all contributed to increasing average life expectancy from 66 years for men and 70 years for women when the NHS was founded, to 78 and 82 years respectively. And many will live well past those averages - there are now more than 12,000 centenarians.

This added life requires a step change in thinking as to how we regard “getting old”. As of 1 October, the Equality Act 2010 has made age discrimination within the NHS illegal, meaning that decisions regarding access to treatment can no longer be made on the basis of age. Chronological age can no longer be used as a shorthand for biological age.

The Royal College of Surgeons, Age UK and MHP Health Mandate undertook a study to assess how treatment rates for common surgical interventions vary according to age, what the reasons behind those variations might be and how they might be addressed.

Elective surgery treatment rates were found to decline steadily for over-65s across a range of common conditions. This creates a stark contrast of increasing health need on the one hand and a decline in use of potentially life-enhancing treatment on the other. For example, while the incidence of breast cancer peaks in the over-85s, the surgery rate peaks about two decades before and declines sharply from around 70.

The rate of elective knee and hip replacement surgery for patients aged in their late 70s and over dropped consistently over the three years that were examined, while the rate of emergency replacements rose sharply from 70 upwards, probably reflecting a lack of preventive services.

Surgery rates for coronary artery bypass graft, colorectal excision, radical prostatectomy, inguinal hernia repair and cholecystectomy (gall bladder removal) also dropped after the late 70s, and in some cases earlier, in marked contrast to the incidence of the conditions the procedures are used to treat.

Age should not be conflated with objective assessments of risk versus benefit or assumptions about the impact or presence of other health conditions (comorbidities) when considering whether someone is a candidate for surgery.

The patient may decide not to go ahead with surgery for personal reasons. Some patients may opt out of joint replacements because they act as carer to a spouse and are put off by the rehabilitation time. Surgery can also be a daunting prospect which some older people may feel they do not want to go through, sometimes because of outdated perceptions. If a patient is rejecting surgery, they must have been given sufficient information to ensure it was an informed decision.

There are also clinical reasons why surgery may not be appropriate; a patient may have other conditions that make it too risky to operate or unlikely that surgery will have a positive outcome. While the likelihood of comorbidities that would make surgery inadvisable rises with age, it is by no means inevitable and so each patient’s suitability must be judged individually rather than based on statistical probabilities.

Unfortunately the decisions about a person’s suitability are sometimes made well before an older person reaches a surgeon: a GP dismissing symptoms as merely signs of age rather than investigating properly and so allowing a condition to develop past the point where surgery would help, for example.

There is little data available on the outcomes of surgery for older people because this group is under-represented in audit data and clinical trials. The Department of Health, National Institute for Health Research and surgical specialty associations also need to strengthen the evidence base to allow informed decision making.

Most importantly, there is absolutely no place for informal “cut-offs” when it comes to surgery. We would not tolerate this type of discrimination in any other group. Neither can the current difficult decisions having to be made to meet the £20bn NHS efficiency drive be allowed to disproportionately have an impact on older people because of a perceived reduction in the cost effectiveness of providing treatment when relative life expectancy is shorter.

Surgery can transform lives, reducing dependency on social care support and allowing greater independence. It can also save lives, giving people back years that they would have otherwise lost to their condition. Older people must have equal access, based on their individual health, to the best possible surgical treatment.

Michelle Mitchell is charity director general, Age UK, and Professor Norman Williams is president of the Royal College of Surgeons.