In the UK the most commonly known reason for kidney failure is diabetes. Poor function is also often caused by compromise of the blood supply to the kidneys (sometimes termed ‘hardening of the arteries’ or ‘poor circulation’) and associated high blood pressure.
Inflammation in the kidneys, problems with urine drainage, and certain genetic disorders are responsible for many of the remaining cases of kidney failure.
It is possible to have quite a poor level of kidney function without feeling unwell. However, when function is very low - what is termed ‘end-stage kidney disease’ - then people will not survive without treatment. Some people, typically with other serious health problems, decide that the best option is to manage the complications of renal failure with medication. This is sometimes called conservative care, or active medical management.
Every year in the UK approximately 100 people in every million, will start treatment for irreversible kidney failure
However, every year in the UK approximately 100 people in every million, will start treatment for irreversible kidney failure. The options are regular dialysis treatments or a kidney transplant.
Treatment - dialysis versus transplantation
Having a successful kidney transplant confers a huge survival benefit compared to dialysis.
This is particularly notable in younger individuals, but there is increasing evidence that even older patients can gain an advantage in survival (quantity not just quality of life) with a transplant compared to dialysis.
Unfortunately not everyone is suitable for transplantation and dialysis may be needed. Most people can remain on dialysis for many and have a good quality of life. However, dialysis is unable to replicate all the normal functions of the kidney, and inevitably this takes its toll. Sadly, this means that people seldom live as long and may die while on dialysis, particularly elderly people and those with other health problems.
Transplantation - living versus deceased donation
Every kidney that is transplanted is a 'second-hand' kidney, generously gifted by the first owner. In the future it may be that we can 'grow' or 'print' new kidneys but we are not at that stage as yet. Currently a kidney is given by someone who is alive and in good health (a living donor), or someone who has died for an unrelated reason (a deceased donor).
Typically the outcomes after living donation are better. Of all the people who received their first kidney transplant in the UK between 2004-2006, nine in ten (or 91%) of those who had a kidney from a living donor were still alive ten years later. This is compared to nearly eight in ten (76%) of those who had a kidney from a deceased donor. While the latter is substantially better than dialysis, the results after living donor transplantation are persistently better every year and in every transplant unit in the UK.
There are two primary reasons for the difference: the quality of the kidney and the 'quality' of the patient at the time of the transplant (i.e. how healthy he/she is).
When a kidney is donated from someone who had died it can have additional injury before it is transplanted.
- Firstly, it tends to be people who are less healthy and may already have poorer kidney function (e.g. smokers, people with diabetes or high blood pressure) who die in a situation when donation might be possible (e.g. not from 'old age').
- Secondly, a catastrophic event, severe enough to result in death, has occurred and often this affects the kidneys.
- Thirdly, unlike in living donation, a deceased-donor kidney cannot be immediately transplanted as it has to be transported o the patient, and there may be delay e.g. with additional tests or need for dialysis before the transplant takes place. If there is a prolonged time before transplantation, the transplanted kidney will not work for as long.
Another very important factor in determining how long a person lives after transplantation is how long he/she was on dialysis before the transplant. Since dialysis is not the same as having normal kidney function, the longer the wait, the less healthy the patient is by the time of transplant, and the shorter their life expectancy afterwards.
Unfortunately, there remain fewer deceased donor kidneys than are needed, so typically there is a delay of years for those waiting for a transplant. However, if someone has a suitable living donor, it is possible for him/her to avoid dialysis altogether (a 'pre-emptive' transplant), which is associated with the best outcome.
Variation in living-donor transplantation
Despite better survival with living donation, there is considerable variability across the UK in the opportunity of patients to have this treatment (reported by the nationwide ATTOM study). People who are younger, white, married, and have higher-level education are significantly more likely to have a living - rather than a deceased donor.
There is also a geographical variation, with a consistently much higher rate of living-donor transplantation in Northern Ireland (NI) than the rest of the UK. The metric used is number of living donors for each million people in the population (per million population or pmp). In 2018-2019, the living-donor rate in NI was 33.2 pmp, in Scotland 19.6 pmp, in Wales 14.4 pmp, and in England 14.1 pmp.
Given the disparity in patient outcomes, and the commonality of the healthcare service across all four countries that is free at point of delivery, such disparity in access to the best treatment perhaps ought to simulate questions or discussion.
Living donors
Being a living donor - having an unnecessary operation and living with a single kidney life-long to help another human being - is a unique process in medicine. It is only possible if we are convinced that, when assessment and donation occurs in accordance with national guidelines, it is a very safe process.
However, the risks of donating and living with one kidney are not, and can never be, zero. Notably there can be a disparity between the view of the medical professionals and a donor/patient in terms of what is considered 'acceptable' risk for a donor, and what is considererd 'success' in terms of transplant outcome. Perhaps detailed consideration of the views of the patients and their families may alter practice in due course. Nevertheless, it will remain of course of fundamental importance that the assessment and care of all potential living donors is exemplary in every aspect.