Kidney Week

Abstract: SA-OR70

Dispelling the Myth of Sex Differences in Lupus Nephritis (LN): A Pooled Analysis of 779 Patients

Session Information

• Glomerular Diseases: Clinical Advances
  October 26, 2024 | Location: Room 6D, Convention Center
  Abstract Time: 05:30 PM - 05:40 PM

Category: Glomerular Diseases

• 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics

Authors

• Nasr, Kristina Karim, University of Minnesota Medical School, Minneapolis, Minnesota, United States

Kristina Karim Nasr, MD

• Coopergard, Ryan B., University of Minnesota Medical School, Minneapolis, Minnesota, United States

Ryan B. Coopergard, PhD

• Ma, Sisi, University of Minnesota Medical School, Minneapolis, Minnesota, United States

Sisi Ma, PhD

• Rovin, Brad H., The Ohio State University Wexner Medical Center, Columbus, Ohio, United States

Brad H. Rovin, MD, FASN

• Nachman, Patrick H., University of Minnesota Medical School, Minneapolis, Minnesota, United States

Patrick H. Nachman, MD, FASN

Background

LN is reported to be more severe and have worse outcomes in men than women based on cohort studies with small numbers of men. We compared LN in men and women utilizing data pooled from 3 randomized controlled trials (RCT) and 7 cohort studies. We aimed to determine if differences exist for: 1- disease severity at diagnosis or flare; 2- first treatment choice; and 3- key outcomes at 1yr.

Methods

Baseline was defined as the date of LN flare. The entire data set was used to compare baseline characteristics between sexes and the outcomes at 1yr (complete renal response; composite of doubling of creatinine, dialysis, or death). Data were imputed using the median for variables with <30% missing data. Analysis of treatment choice (4 groups: cytotoxic, antimetabolite, calcineurin inhibitor, other) used only cohort data. Descriptive statistics used two-sample t-tests or Chi-square. Mixed model regression with studies as the random effects, controlled for age and race, were used to determine the effect size and p-values of sex on key clinical variables. For outcomes, we used logistic regressions controlling for treatments and baseline characteristics significantly correlated to outcomes.

Results

The pooled cohort included 94 men and 675 women (25% Asian, 11% Black, 53% White, 11% other). There were no statistically significant differences between sexes in age, race, duration of SLE or LN, C3, anti-dsDNA, LN class distribution or SLE Disease Activity Index 2K. No deaths were recorded. Key findings are in the table.

Conclusion

Compared to women, men have a lower eGFR and more proteinuria at baseline, but have similar LN class distribution and fewer have low C4. The lower eGFR may be related to markers of kidney histopathology (e.g. activity or chronicity indices) or comorbidities that were not captured. We found no significant outcome differences between sexes at 1yr adjusting for relevant variables in this large international pooled analysis.