Impact of race on comorbidity burden and clinical outcomes among Southeast Asians with lupus nephritis: a single-center retrospective study.

AIM: Data on lupus nephritis (LN) prognosis in the diverse Asian races outside of East Asia is scarce. We aimed to evaluate the cardiometabolic comorbidity burden and outcomes of LN in a multi-racial Southeast Asian population. METHODS: Single-center, retrospective cohort study of 340 patients with biopsy-proven LN between 2011 and 2023. The outcome was kidney failure and/or death. RESULTS: Among Chinese (252 patients), Malay (57 patients), Indian (11 patients) and other races (20 patients), the median age was 42.3 years (interquartile range 31.4-52.8). Chinese were older at diagnosis than other races (p = 0.002). Malays were less likely to be older than Chinese (odds ratio [OR] 0.33, 95% confidence interval [CI] 0.18-0.61). Diabetes mellitus was more frequent in Malays (OR 3.05, 95% CI 1.04-8.97) and Indians (OR 5.65, 95% CI 1.06-30.06) than Chinese. Compared to Chinese and Malays, other races were less likely to have hypertension and renin-angiotensin system blocker (OR 0.27, 95% CI 0.08-0.96 and OR 0.20, 95% CI 0.06-0.69, respectively). There were no differences in hyperlipidemia, ischemic heart disease, kidney histology, and induction immunosuppressant type. During the median follow-up of 50 (38, 74) months, 49 patients (14.4%) developed kidney failure and/or died. Adjusting for cardiometabolic risk factors (age > 40 years, male sex, eGFR < 60 ml/min/1.73 m2, diabetes mellitus, hypertension, hyperlipidemia and ischemic heart disease), race was not significantly associated with patient and kidney survival, but reduced kidney function (adjusted OR 5.77, 95% CI 2.77-12.01) was. CONCLUSION: Future studies should include under represented ethnic groups to better understand race-specific cardiometabolic risk profiles and their effects on LN outcomes.