Kidney Transplants Benefit Patients With SCD, But Few Have Chance to Receive Them

March 5, 2021
Allison Inserro

Despite benefitting from organ transplants similarly to other patients with kidney failure, a new study found patients with kidney failure associated with sickle cell disease (SCD) are less likely to receive transplants.

Despite benefitting from organ transplants similarly to other patients with kidney failure, a new study examining patients with kidney failure associated with sickle cell disease (SCD) found that these patients are less likely to receive them.

Both findings were revealed in research published in Clinical Journal of the American Society of Nephrology this week.

SCD is a risk factor for kidney failure, and those with SCD on long-term dialysis have high mortality rates. Historically, these patients have not been offered transplants if their providers thought that these efforts would be futile. What isn’t known, however, is whether the mortality of these patients with SCD after a transplant would still be lower than mortality while on dialysis, noted the authors from Johns Hopkins University.

Therefore, the 2 aims of the study were to quantify the reduction in mortality associated with kidney transplantation and determine the chance that patients with SCD would receive a transplant (ie, by measuring access to transplants through starting dialysis, getting on a waitlist, and receiving a transplant).

The team examined US national registry data of all adults with kidney failure who began maintenance dialysis or were added to the kidney transplant waitlist from 1998 to 2017. This study used 2 national registries: the United States Renal Disease System and the Scientific Registry of Transplant Recipients.

Mortality risk was compared between kidney transplant recipients with SCD with those who received a transplant but did not have SCD. There were 2 cohorts (those on dialysis and those on a waitlist). The dialysis group included 1970 patients in the sickle cell group, and 2,047,790 patients in the control group. The waitlist cohort included 507 patients in the sickle cell group and 463,298 in the control group.

The final analysis showed that patients who received a transplant—whether they had SCD or not—had lower rates of death compared with patients who were still on a list.

Better patient survival after transplantation was similar among transplant recipients who had SCD and those who did not; those who had transplants had a 20 percentage point better survival over 10 years (98.75% CI, 0.9-39.8) compared with 19.8 percentage points (98.75% CI, 19.2-20.4) in the control groups.

However, patients with SCD were 27% less likely to undergo transplantation than patients without the disease (subdistribution HR, 0.73; 95% CI, 0.61-0.87).

Waitlisted candidates with SCD were 38% less likely to receive a transplant than other patients (subdistribution HR, 0.62; 95% CI, 0.53-0.72).

“Our study findings lend strong support to the viewpoint that transplantation is a valuable treatment option for patients with sickle cell–associated kidney failure,” Sunjae Bae, PhD, MPH, an instructor of surgery, said in a statement.

Reference

Bae S, Johnson M, Massie AB, et al. Mortality and access to kidney transplantation in patients with sickle cell disease–associated kidney failure. Clin J Am Soc Nephrol. Published online February 25, 2021. doi:10.2215/CJN.02720320