The number of people receiving kidney transplants in Scotland has not yet returned to pre-pandemic levels, according to a new audit.

The report by the Scottish Renal Registry also notes that the 10 year survival rate for kidney transplant patients has "fallen significantly" in recent years and that fewer than half of transplant and dialysis patients took up the offer of the most recent Spring Covid booster.

The annual analysis of trends among kidney failure patients found that a total of 247 kidney transplants took place in Scotland during 2022, including 155 from deceased donors and 92 living-donor transplants.

This compares to 270 in 2021 and 235 in 2020.

READ MORE: Inflation, Covid, budget cuts - is the NHS recovery crumbling? 

However, in the three years prior to the pandemic Scotland's kidney transplant centres in Glasgow and Edinburgh were carrying out around 300 transplants per year.

The Herald: The number of kidney transplants remains lower compared to 2017, 2018 and 2019 levelsThe number of kidney transplants remains lower compared to 2017, 2018 and 2019 levels (Image: PHS)

As of March 31 2022, there were 230 patients on the kidney transplant waiting list for Glasgow and 149 on the list for Edinburgh.

The report states: "The Covid-19 pandemic has had a significant impact on transplantation and although there was a 5.1% increase in overall kidney transplants performed in 2021 compared to 2020, transplant activity has not yet recovered to pre-pandemic levels."

Between 1961 and 2022, a total of 7,385 kidney transplants have been carried out in Scotland including four cases where patients have had to receive a fifth kidney transplant due to incurable conditions which cause their body to attack the organ.

The Herald: Transplant rates from deceased donors are fallingTransplant rates from deceased donors are falling (Image: PHS)

The rate of kidney transplants coming from deceased donors has fallen from a peak of just over 40 per million in 2017 to around 28 per million last year, which the audit said "may reflect several factors, including a reduction in overall donor numbers in the UK in 2020–2022".

While Scotland introduced opt-out legislation in 2021, meaning that people are automatically considered organ donors unless they have registered an objection, the pandemic was also associated with a reduction in people dying in ways which lend themselves to donation - such as through car accidents.

There have also been changes in how organs are distributed, including the introduction of a national allocation scheme from 2019 which means that kidneys will be matched on a UK-wide rather than regional basis according to patients who are most likely to benefit.

READ MORE: UK's first womb transplant a 'massive success'

Ten-year post-transplant survival has also "fallen significantly" from 91.8% among those who received their donor kidney 2008, to 76.5% for those whose transplant surgery took place in 2012.

The report said this may reflect "changes in donor and recipient demographics, an ageing population and Covid-19" but that "further work is required to fully understand these data".

One-year survival also fell from 99.6% for those whose operations took place in 2019 to 95.3% for those transplanted in 2021.

The Herald: Survival rates have fallen in recent years, possibly reflecting the impact of CovidSurvival rates have fallen in recent years, possibly reflecting the impact of Covid (Image: PHS)

The report also highlights how the impact of Covid and vaccine uptake among kidney failure patients has changed over the pandemic.

Kidney patients are particularly vulnerable to worse outcomes from Covid, but uptake of vaccinations among this patient group has fallen from a peak of 88.2% for the first three doses to 43.8% for the 2023 Spring booster, with coverage as low as 30% for dialysis patients as of June 2023.

The Herald: Covid cases over time among kidney transplant patients against vaccine coverage and 28-day survivalCovid cases over time among kidney transplant patients against vaccine coverage and 28-day survival (Image: Scottish Renal Registry report)

The Herald: Covid cases over time among kidney dialysis patients, against vaccination coverage and 28-day survivalCovid cases over time among kidney dialysis patients, against vaccination coverage and 28-day survival (Image: Scottish Renal Registry)

The number of kidney failure patients testing positive for Covid also rose steeply between mid-2021 and mid-2022, coinciding with the emergence of the highly transmissible Omicron strain and the lifting of most mitigations.

However, mortality and hospitalisations for Covid - while still higher for the general population - are decreasing "for both dialysis and transplant patients" due to the effects of vaccines, antivirals, and other treatments.

READ MORE: Covid winter vaccine rollout accelerated amid new variant concerns 

By March 2022, when a peak of 176 Covid cases were detected among kidney dialysis patients, the 28-day survival rate was 98% compared to a low of 58% in November 2020.

Among kidney transplant patients, Covid cases peaked at 150 in December 2021 but survival had gone from 62-69% in March and April of 2020 to 98%.