Lupus nephritis (LN) mortality rates have decreased overall from 1999, but researchers identified a significant increase from 2015 to 2019 among those who are non-White and those living in large central metropolitan areas. Study results were presented at the American College of Rheumatology (ACR) Convergence 2021, held virtually from November 3 to 10, 2021.
Although large strides have been made in research and therapy during the previous 20 years, systemic lupus erythematosus (SLE) mortality still remains disproportionately high relative to general population mortality.
Researchers sought to analyze mortality trends from 1999 to 2019 and identify population characteristics associated with LN mortality, using information from the US Centers for Disease Control and Prevention (CDC)’s WONDER database.
Data for SLE and LN mortality were categorized by race, ethnicity, and urbanization. Race and ethnicity data were classified into the following groups: Hispanic, non-Hispanic White, non-Hispanic Black, non-Hispanic American Indian/Alaska Native, and non-Hispanic Asian/Pacific Islander. Urbanization was defined by population size: large central metropolitan, large fringe metropolitan, medium metropolitan, small metropolitan, micropolitan, and nonmetropolitan, based on 2006 urbanization data.
There were a total of 25,973 deaths from SLE and 8899 deaths from LN between 1999 and 2019. According to the joinpoint regression analysis, the SLE age-standardized mortality rate continuously decreased from 1999 through 2009, plateaued between 2009 and 2012, and again decreased from 2012 to 2015. The rates of LN underwent an overall 26.1% decrease in 21 years; however, LN mortality rates significantly increased from 2015 to 2019.
Researchers found that although Black individuals only account for 12.8% of the US population, they accounted for 38% of all LN deaths. Lupus nephritis mortality among Black patients was 6-fold higher than among White patients, and more than 2-fold higher than among all other racial and ethnic groups. Lupus nephritis mortality was also significantly higher among Hispanic, American Indian/Alaska Native, and Asian/Pacific Islander groups than among the White group.
The large central metropolitan area had the highest mortality rate, accounting for 35.1% of LN deaths (P <.05 relative to all other areas), followed by medium metropolitan areas.
The researchers concluded, “Studies are urgently needed to understand reasons underlying these disparities and the recent worsening trend.”
Yen E, Rajkumar S, Sharma R, et al. Lupus nephritis mortality in the United States, 1999-2019: profound disparities by race/ethnicity and place of residence and a recent worsening trend. Presented at: ACR Convergence 2021; November 3-10, 2021. Abstract 0454.
This article originally appeared on Rheumatology Advisor