SAN DIEGO – Receiving a kidney transplant increased the likelihood of survival in patients with end-stage renal disease (ESRD) due to granulomatosis with polyangiitis, a study showed.
“We found that there was a huge survival advantage of having a renal transplant,” lead author Zachary S. Wallace, MD, MS, of Harvard Medical School, Boston, said in an interview. “In addition, this improvement in survival seems to be due to a dramatic reduction in death due to cardiovascular disease.”
The number of people with the potentially deadly, granulomatosis with polyangiitis (GPA), a small-vessel vasculitis, is unclear. However, a 2017 analysis of residents of Olmsted County, Minn., over a 20-year period estimated the annual incidence at about 3.3/100,000 (Arthritis Rheum. 2017 Nov 9. doi: 10.1002/art.40313).An estimated 25% of patients with GPA develop ESRD, according to Dr. Wallace, who also works at the vasculitis and glomerulonephritis center at Massachusetts General Hospital, Boston. “GPA and ANCA [antineutrophil cytoplasmic autoantibody]–associated vasculitis in general have a propensity to affect the kidneys, and the reason for that is not entirely known,” he said during the interview. “In the kidney, it most commonly causes a rapidly progressive glomerulonephritis which can cause irreversible renal failure if not aggressively treated.”
Dr. Wallace and his colleagues launched their study to better understand the impact of kidney transplants. “We know that patients with ESRD from more common causes – such as diabetes and hypertension – benefit in terms of survival and quality of life from transplantation,” he said in the interview. “It was unknown if GPA patients similarly benefit. Often, GPA patients have fewer comorbidities than patients with ESRD due to diabetes or hypertension. Since they may be relatively healthier, one might wonder if the survival benefit would be as great in ESRD patients with GPA.”
Dr. Wallace and his colleagues tracked 2,471 cases of ESRD due to GPA from the U.S. Renal Data System. All were wait-listed for a kidney transplant from 1995 to 2014, and the researchers tracked them as late as Jan. 1, 2016. Of the patients studied, 946 received a transplant. The study’s participants tended to be male (59%) and white (86-87%), and they rarely had comorbidities outside of diabetes (64-67%).
There were 438 deaths in the entire group. Those who received transplants were much less likely to die than those who didn’t (adjusted hazard ratio, 0.30; 95% confidence interval, 0.25-0.37; P less than .001), he reported at the annual meeting of the American College of Rheumatology.
Also, those who received transplants were much less likely than those who didn’t to die of cardiovascular disease (adjusted HR, 0.13; 95% CI, 0.08-0.22; P less than .001) and infection (adjusted HR, 0.61; 95% CI, 0.34-1.08; P = .09). There was no statistically significant difference between the groups in terms of deaths from cancer.
“The improvement in survival seems to be due to a dramatic reduction in death due to cardiovascular disease,” Dr. Wallace said in the interview. “While cardiovascular disease is a common cause of death in GPA and ESRD due to other causes, this was not known specifically in patients with ESRD due to GPA.”
The findings provide the following messages to rheumatologists: Renal transplantation in patients with ESRD due to GPA offers a significant survival benefit, and it is important to refer patients early to a renal transplant center, he noted.
“[Rheumatologists] should work closely with primary care physicians and nephrologists to make sure that the patient’s cardiovascular disease risk is being assessed – checking lipids, A1c, etc. – and addressed as necessary,” Dr. Wallace added.
The study authors reported no relevant financial disclosures. Funding included support from the Rheumatology Research Foundation, the Executive Committee on Research at Massachusetts General, and the National Institutes of Health Loan Repayment Program.