Children and adults with end-stage renal disease (ESRD) secondary to systemic lupus erythematosus (SLE) have a higher risk of death than those with other types of kidney disease, according to a study by Sule et al.1
Based on an analysis of United States Renal Data System records from more than 98,000 children and adults with various forms of ESRD (not limited to SLE), the researchers found that kidney disease in children with SLE was more than twice (2.4 times) as lethal compared with pediatric patients with ESRD secondary to other causes. Adult SLE patients had a 1.7 times–higher risk of dying than adults with other forms of ESRD.
In both pediatric and adult SLE populations, the vast majority of deaths were attributed to cardiovascular disease; however, the affects were primarily noted in children. Three quarters of the children with SLE kidney disease who died did so from heart problems, mostly heart attacks. By comparison, only 26% of children with nonlupus kidney disease died from heart problems.
The researchers said that SLE triggers chronic inflammation and that lupus patients seem more likely to develop hypertension and high cholesterol at an unusually early age. “Inflammation may play a pathological role in the development of cardiovascular disease,” they commented, adding that “an increased inflammatory state leading to atherosclerosis may account for the much young age at death for the adult patients with ESRD secondary SLE compared with other patients.”
“What we may be seeing here is a double whammy of cardiovascular damage—on the one hand, there’s the damage caused by lupus itself, further compounded by the resulting kidney disease,” said lead investigator Sangeeta Sule, MD, PhD, a pediatric nephrologist and SLE expert at Johns Hopkins Childrens Center in Maryland, in a news release.
While 75% of deaths in children were attributed to heart disease, 25% were attributed to septicemia/infections. These causes accounted for half of deaths in adults with ESRD secondary to SLE, as well—30% from cardiovascular disease and 20% from infections. In adult and pediatric patients with other causes of ESRD, cardiovascular disease and infections were also common causes of death, at 25% and 8% of adult deaths and 26% and 12% of pediatric deaths, respectively.
Rheumatologists Weigh In
“It would be interesting to see if there is a difference in mortality rates among the adult onset dialysis patients with SLE if their SLE began before or after age 18,” according to a written comment to The Rheumatologist from rheumatologists Anne Eberhard, MD, of North Shore-Long Island Jewish Health System, and Emily von Scheven, MD, of the University of California, San Francisco.
They added that, “causes of death were broadly based as to organ system. No autopsy results were given, so cardiovascular for the pediatric patients predominated.” However, the type of cardiovascular disease and cardiac arrest was not included in the paper, “which really is a nebulous diagnosis,” they wrote. “This makes conclusions difficult.”
“The authors’ conclusions [regarding] an increase in mortality from pediatric SLE with ESRD likely secondary to cardiovascular disease are valid,” Drs. Eberhard and von Scheven continued. “But the etiology for this—i.e., hypertension, atherosclerosis, etc.—cannot be determined by this study. Nor can any new treatments be deduced or recommended from these findings.”
In their study conclusions, the authors commented that, “pediatric and adult patients with ESRD secondary to SLE need careful monitoring and aggressive treatment for traditional risk factors for atherosclerosis, such as hypertension and obesity. Additionally, they should also be evaluated for more nontraditional risk factors, which could result in an inflammatory state and contribute to cardiovascular disease.”
Sue Pondrom is a medical journalist based in San Diego.
Reference
1. Sule S, Fivush B, Neu A, Furth S. Increased risk of death in pediatric and adult patients with ESRD secondary to lupus. Pediatr Nephrol. 2011;26:93-98.
