Trajectories of NT-ProBNP in Systemic Lupus Erythematosus

Objectives Patients with systemic lupus (SLE) are at increased risk of cardiovascular disease. N-terminal prohormone of brain natriuretic peptide (NT-proBNP), a biomarker of cardiac dysfunction, is elevated and associated with cardiovascular damage in this population.[1] However, trajectories of NT-proBNP in SLE have not been investigated. We examined NT-proBNP trajectories and explored cross-sectional associations with demographic and disease characteristics. Methods We analyzed demographic, clinical, and laboratory data from the McGill SLE Research Cohort. Serum NT-proBNP levels were measured yearly from March 2022 to May 2025. We assessed the prevalence of elevated NT-proBNP (≥133 pg/mL),[1] at baseline, and determined baseline variables: age, sex, race/ethnicity, age at SLE diagnosis, SLE duration, smoking, and SLE International Collaborating Clinics (SLICC) Damage Index. Univariate and multivariate linear regressions identified independent associations with baseline log-transformed NT-proBNP (Table 1). Patients were classified into 4 NT-proBNP trajectories: abnormal at baseline and remained abnormal; abnormal and normalized; normal and became abnormal; normal and remained normal. We compared baseline characteristics across trajectories using multivariate logistic regressions. Table 1: Exponentiated coefficients of univariate vs multivariate linear regression analyses for outcome of log-transformed baseline NT-pro-BNP Results We studied 294 patients with ≥2 measurements. At baseline, 101 (34.4%) had elevated NT-proBNP. The mean NT-proBNP levels were 243.6 pg/mL, median 91, interquartile range, IQR 55-171.8. Higher levels were significantly associated with female sex, white race, older age at SLE diagnosis, and longer SLE duration. Cardiovascular damage, pulmonary hypertension, and renal damage were also independently associated with higher NT-proBNP. Of the 101 individuals with abnormal baseline NT-proBNP, 79 (78.2%) remained abnormal at second assessment. Of the 193 with normal baseline levels, 30 (15.5%) became abnormal. No patient with a baseline level ≥350 normalized to <133. Compared to other trajectories, high-risk trajectories (abnormal remained abnormal and normal became abnormal) were more likely to have cardiovascular damage (OR 3.90, 95% CI 1.49-12.48, renal damage (OR 2.87, 95% CI 1.61-5.51), and pulmonary hypertension (OR 31.99, 95% CI 4.59-651.10). Conclusion Over one-third of patients had abnormal baseline NT-proBNP, and most (78%) remained abnormal, while over 15% of those with an initially normal value became abnormal. Higher levels were associated with female sex, white race, older age at diagnosis, longer SLE duration, and organ damage. Levels ≥350 pg/mL did not normalize over our evaluation. High-risk trajectories were associated with SLICC damage items (cardiovascular damage, renal damage, and pulmonary hypertension – though the 95% CI for pulmonary hypertension was very wide). Future analyses will examine associations with electrocardiogram and echocardiographic results. References [1.] Sacre K. Rheumatology (Oxford) 2024;63:1739-45. Best Abstract on SLE Research by a Trainee – Ian Watson Award