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Jume 19, 2024
People with HIV in Ontario less likely to get a kidney transplant
- Researchers analyzed health data of Ontarians with severe kidney injury who required dialysis
- Those eligible for kidney transplants were less likely to receive one if they were living with HIV
- Researchers called for organ transplantation programs to investigate disparities in access
HIV treatment (antiretroviral therapy; ART) is highly effective and safe. When used as directed, ART suppresses the amount of HIV in the blood to very low levels, commonly called “undetectable.” Researchers are finding that people with this low level of viral suppression do not pass on the virus to their sexual partners. What’s more, studies increasingly project that ART users will live well into their senior years.
However, ART cannot resolve every issue related to HIV. For instance, residual amounts of HIV remain deep within tissues (such as the brain) as well as in parts of the immune system (such as the spleen and lymph nodes). This residual HIV may in part be responsible for ongoing inflammation and excess activation of the immune system. Studies in people without HIV suggest that prolonged and excessive inflammation contributes to an increased risk for the following health issues:
- cardiovascular disease
- cancer
- type 2 diabetes
- depression
- degenerative conditions of the brain
- fat accumulation in the liver
- thinning of bones (osteopenia and osteoporosis)
- high levels of cholesterol
- kidney injury
- loss of muscle tissue
- breathing problems
- premature aging of the immune system
It is therefore possible, likely even, that chronic excess inflammation in people with HIV also contributes to an increased risk for the above issues, including kidney injury.
The kidneys filter blood and release waste products into the urine. When the kidneys become injured, their filtration ability decreases. In severe cases of kidney injury, affected people may require visits to a dialysis clinic, where their blood is filtered by a machine. Some people experience such severe kidney injury that they require a transplant.
Impact of HIV
Studies from the U.S. and Denmark have found that the risk of kidney injury is heightened among people with HIV. Although the widespread availability and use of ART has helped to normalize survival among people with HIV, this population is still at risk for kidney injury and chronic kidney disease that degrades these vital organs. In the current era, studies have found that people with HIV who have severe kidney injury and who require dialysis are at increased risk for complications and dying.
In Ontario
A team of researchers at universities in Southern Ontario reviewed health-related information collected in databases. Ontario is the province with the largest population, with more than 15 million residents. The research team estimated that about 50% of all organ transplants in Canada occurred in Ontario.
By accessing databases, the researchers found more than 40,000 people who had severe kidney injury and who required dialysis. They divided participants of the study into two groups:
- 40,513 people without HIV
- 173 people with HIV
Differences between the two groups
In the study, on average, people with HIV were generally younger than people without HIV (53 years vs. 68 years old). There were proportionately fewer women with HIV (23%) than women without HIV (39%).
The researchers found that people with HIV were less likely to have the following complications than people without HIV:
- cancer
- chronic obstructive pulmonary disease (COPD)
- type 2 diabetes
- high blood pressure
- heart failure
Distribution of transplants
Over the course of the study period (2007 to 2020), the overall distribution of kidney transplants between the two groups at first appeared to be only slightly different, with 13% of HIV-negative people getting a kidney and 12% of HIV-positive people getting a kidney.
However, the researchers performed a sensitivity analysis of the data on a subset of 26,017 people who did not have conditions that precluded them from getting a kidney transplant. In this analysis, there were 25,868 people without HIV and 149 people with HIV. The sensitivity analysis found that the distribution of kidney transplants was as follows:
- people without HIV – 20%
- people with HIV – 13%
This difference in the distribution of kidney transplants was statistically significant; that is, not likely due to chance alone.
People who are on a waiting list for kidney (and other organ) transplants are often ill and are at elevated risk of dying. The researchers examined the rate of pre-transplant deaths in both groups of people and found that it was not significantly different.
After transplantation
Organ transplantation requires prolonged and delicate surgery and carries risks. The donated organ is sometimes recognized as foreign by the recipient’s body. As a result, the recipient’s immune system can attack the transplanted organ, degrading and sometimes destroying it. To minimize the risk of this happening, doctors prescribe transplant drugs that can partially weaken the recipient’s immune system. There is a delicate balance of immune suppression that is sought by doctors, one that keeps the transplanted organ safe yet does not significantly increase the risk of severe infections occurring in the recipient.
Overall, in the present study 5,334 people received a kidney transplant. Sometimes after transplantation the new kidneys may not work, and patients must return to getting dialysis. Such cases were relatively small in the present study (19 HIV-negative people and less than six HIV-positive people. This difference between groups was not statistically significant.
As people on transplant waiting lists are usually quite ill, there is still a risk of dying even after a transplant is done. In the present study, 861 people without HIV (16%) and less than six people with HIV died after transplantation. This difference was also not statistically significant.
Digging into the disparity of distribution of kidney transplants
As mentioned earlier, researchers found that there was a significant difference in the distribution of kidney transplantations. The researchers found that this difference was not driven by the following factors:
- comorbidities (pre-existing conditions such as heart disease, lung disease, diabetes, cancer and so on)
- place of residence (Greater Toronto Area vs. non-GTA, urban vs. rural)
The researchers advanced the following possible explanations to explain why people with HIV were less likely to get a kidney transplant:
- socio-economic factors
- reluctance of transplant programs to consider people with HIV because of fears that transplant drugs (used to weaken the immune system) may have complex interactions with some medicines used to treat HIV
- concerns that people with HIV might be at heightened risk at losing the transplanted kidney because their immune systems could not be sufficiently suppressed (because too much immune suppression could lead to a risk of severe infections)
However, as the researchers were only able to review bio-medical data from databases in Ontario, they could not be certain as to why the disparity in access to transplanted kidneys occurred. The researchers did state that the disproportionate access to transplanted kidneys needs to be brought to the attention of organ transplant programs in Ontario.
The researchers cited reports from Central and Eastern Europe where people with HIV who need kidney transplants are not getting them. They also stated that despite an improvement in access to kidney transplants in recent years by people with HIV in the U.S., “substantial barriers” to access still exist.
The researchers noted that in the current era, studies suggest that people with HIV who do receive a kidney transplant have good rates of survival comparable to people without HIV.
Bear in mind
The study’s results were disappointing in that they underscored unequal access to kidney transplants for people with HIV in Ontario. However, they can serve as a call to action for hospitals and transplant centres to do better for the populations that they serve, including people with HIV.
—Sean R. Hosein
Resources
U.S. study uncovers vitamin C loss and deficiency in some women with HIV – CATIE News
Can a diet rich in fruit and vegetables help the kidneys over the long term? – CATIE News
Large study confirms near-normal life expectancy for many people on HIV treatment – TreatmentUpdate 249
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