Cardiovascular disease (CVD) is accelerated in patients with systemic lupus erythematosus (SLE) and lupus nephritis (LN). Despite the literature suggesting renal arteriosclerosis predicts CVD in other glomerulonephritis diseases, arteriosclerosis grading and reporting might be particularly overlooked in LN biopsies. We aimed to examine the burden of renal arteriosclerosis in LN and to assess whether arteriosclerosis is under-reported in LN biopsies.
We identified all LN patients undergoing kidney biopsy between 1994 – 2017 at an academic center. We interpreted LN biopsy reports to classify the Banff categories of absent, mild, moderate, or severe renal arteriosclerosis. The prevalence of renal arteriosclerosis was compared with the prevalence published for age-matched healthy peers, and predictors of arteriosclerosis were examined. We over-read biopsies for Banff renal arteriosclerosis grading and compared to pathology reports.
Among 189 incident LN patients, renal arteriosclerosis prevalence was two decades earlier in LN patients compared to their healthy peers, affecting 40% of 31-39 yo LN compared to 44% of 50-59 yo healthy peers. A multivariable analysis showed a 3-fold higher odds of renal arteriosclerosis in LN patients over age 30. LN chronicity on biopsies predicted a 4-fold higher odds of renal arteriosclerosis. The over-reads determined that 50% of standard LN biopsy reports missed reporting the presence or absence of renal arteriosclerosis.
Renal arteriosclerosis is accelerated by two decades in LN patients compared to their healthy peers and overlooked by pathologists in half of the routine biopsy reports. We propose incorporating Banff renal arteriosclerosis grading in all LN biopsies.