High Burden of Premature Arteriosclerosis on Renal Biopsy Results in Incident Lupus Nephritis

Abstract

Objective Cardiovascular disease (CVD) is accelerated in patients with systemic lupus erythematosus and lupus nephritis (LN). Despite the literature suggesting that renal arteriosclerosis predicts CVD in other glomerulonephritis diseases, arteriosclerosis grading and reporting might be particularly overlooked in LN biopsies. Our objective was to examine the burden of renal arteriosclerosis in LN and to assess whether arteriosclerosis is underreported in LN biopsies. Methods We identified all patients with LN undergoing kidney biopsy between 1994 and 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 overread biopsies for Banff renal arteriosclerosis grading and compared to pathology reports. Results Among 189 incident patients with LN, renal arteriosclerosis prevalence was 2 decades earlier compared to their healthy peers, affecting 40% of patients ages 31–39 years with LN compared to 44% of healthy peers ages 50–59 years. A multivariable analysis showed a 3‐fold higher odds of renal arteriosclerosis in patients ages ≥30 years with LN. LN chronicity on biopsy results predicted a 4‐fold higher odds of renal arteriosclerosis. The overreads determined that 50% of standard LN biopsy reports missed reporting the presence or absence of renal arteriosclerosis. Conclusion Renal arteriosclerosis is accelerated by 2 decades in patients with LN compared to their healthy peers and is overlooked by pathologists in half of the routine biopsy reports. We propose incorporating Banff renal arteriosclerosis grading in all LN biopsy reports.

Association of Renal Arteriosclerosis With Atherosclerotic Cardiovascular Disease Risk in Lupus Nephritis

“…We used similar methods as published in our recent paper: we analyzed key cutoffs for age and SLE duration before LN diagnosis and examined associations between ASCVD and a composite of reported and overread r-ASCL (17). Along with basic sociodemographic data, variables with a P value of <0.1 in univariable models and LN proliferative class were included in multivariable analyses.…”

“…Renal biopsy was performed for clinical indication (edema, increase in serum creatinine, hematuria, and/or proteinuria), and pathologic assessments were performed using the 2003 ISN/RPS classification for LN. We abstracted the following data from renal pathology reports: 1) LN class (I–VI), which was further categorized into proliferative or nonproliferative LN, and 2) reported r‐ASCL data were abstracted from renal pathology reports and were classified into the Banff r‐ASCL grading categories as described in our previous manuscript (17).…”

“…Yet, a few studies including LN biopsies failed to report a similar association between the presence of severe r‐ASCL and ASCVD occurrence (15,16). We previously reported an accelerated and higher burden of moderate‐severe r‐ASCL in LN patients, at the time of LN diagnosis, compared to healthy peers (17). Furthermore, we reported an 80% positive predicted value of reported r‐ASCL that indicated the accurate grading and reporting of r‐ASCL by a pathologist when r‐ASCL was present.…”