Incidence of Lupus-Nephritis-Related ESRD Highest in Blacks
SAN FRANCISCO—The incidence of end-stage renal disease (ESRD) due to lupus nephritis (LN) rose significantly in the United States from 1995 to 2004, according to new study data presented here at the American College of Rheumatology annual meeting. The incidence was significantly higher among African Americans and women.
In addition, the study demonstrates that the incidence of LN-related ESRD is higher in African Americans than Caucasians, a finding that could be related to decreased access to care and diminished efficacy of treatments among African Americans.
Researchers at Brigham and Women's Hospital in Boston used information from the U.S. Renal Data System (USRDS) and 2000 U.S. Census data to study kidney failure among patients with lupus. The USRDS includes data on approximately 94% of all U.S. patients with ESRD.
A total of 10,035 cases of LN-associated ESRD occurred during the study period. The number of new cases per year rose 30% in the entire population, with the highest number of cases occurring in those aged 20-39 years. Most cases (82%) occurred among women.
The number of new cases per year increased 32% among women and 37% among African Americans, higher than in any other racial or ethnic group. Among Caucasians, the incidence rate rose 18%. ESRD due to lupus occurred most frequently among African American women, in whom the disease afflicted 36 of one million individuals per year. By comparison, lupus occurred in 3.5 of one million Caucasian women per year,
“Our findings suggest that minority racial and ethnic groups in the United States may not be receiving adequate health care for lupus and lupus nephritis, and/or they are not responding to treatment in the same way as Caucasians,” said lead investigator Karen Costenbader, MD, MPH, assistant professor of medicine at Harvard Medical School and a rheumatologist at Brigham and Women's Hospital.
Dr. Costenbader, who presented the study findings, said compliance with therapeutic regimens may be an issue.
“We now know that there are huge disparities in incidence and we need to figure out why,” Dr. Costenbader told Renal & Urology News.
“We don't know if [the disparities are] related to the underlying genetics of the disease, but probably the genetics are not changing over 10 years. So is [the problem] access to care? Is it adherence with medications or response to therapy? Is it environmental exposures? We just don't know. This is an area that needs a lot more research.”