IgAN and Risks of Kidney and Cardiovascular Events and Death

Few population-based data exist in the U.S. about adults with IgA nephropathy (IgAN) and risks of kidney, cardiovascular, and mortality outcomes versus those with nonglomerular chronic kidney disease (CKD) or without CKD.

We applied natural language processing (NLP) algorithms to electronic health record (EHR) data within a large integrated healthcare delivery system to identify adults with biopsy-proven IgAN between 2010 and 2020. We next identified 2 separate comparison cohorts of adults with nonglomerular CKD and adults without CKD matched on age and sex, and compared the rates of end-stage kidney disease (ESKD), worsening CKD, acute kidney injury (AKI), cardiovascular outcomes, and death through 2021 using multivariable Cox proportional hazards models.

We identified 1651 adults with biopsy-confirmed IgAN who had a mean age of 43 years and 48% women, 41% Asian or Pacific Islander, and 3.3% Black. Compared with matched adults with nonglomerular CKD (n = 9863), those with IgAN had higher adjusted rates of ESKD (adjusted hazard ratio [aHR]: 2.79, 95% CI: 2.16-3.62), worsening CKD (aHR: 3.05, 95% CI: 2.68-3.46), and AKI (aHR: 1.45, 95% CI: 1.22-1.73) but no significant adjusted differences in cardiovascular events and death. Compared with matched adults without CKD (n = 16,510), patients with IgAN had substantially higher adjusted rates of adverse kidney outcomes as well as higher adjusted rates of hospitalization for heart failure (aHR: 8.06, 95% CI: 2.90-22.37) and death (aHR: 2.90, 95% CI: 2.08-4.02) but not acute myocardial infarction or stroke/transient ischemic attack.

Adults with IgAN are at greater risk of adverse kidney outcomes versus nonglomerular CKD and substantially higher risks of heart failure and death compared with no CKD.