Researchers of a recent population-based inception cohort from Southeast Norway (2000–2017) included 700 medical record–confirmed new-onset patients with systemic lupus erythematosus (SLE) meeting 2019 European Alliance of Rheumatology Associations/American College of Rheumatology criteria and followed for a mean of 8 years. Antiphospholipid syndrome (APS) was defined by 2006 Sydney criteria and antiphospholipid antibodies (aPL) per guidelines. Key outcomes were thromboembolic events (TE), APS, and death, analyzed with Kaplan–Meier methods. Overall, 13% (89/700) experienced a new TE. TE and APS clustered near SLE diagnosis, particularly among the 34% who were aPL-positive at onset.
Risk was highest in the first year: TE incidence reached 59 per 100 person-years (95% confidence interval [CI] 38–87) in aPL-positive patients with APS, then fell to 12 (95% CI 6.2–21) in years 2 to 5. In patients without APS, rates were 2.6 (95% CI 1.4–4.3) and 0.9 (95% CI 0.5–1.4), respectively. aPL-negative patients <50 had the lowest risk (1-year TE-free survival 0.99; 95% CI 0.97–1.00), and beyond year one, TE-free survival no longer differed by aPL status. Standardized mortality rates were higher with APS than without (4.7 [95% CI 1.8–10.7] vs 1.7 [95% CI 1.2–2.3]). Findings underscore the need for heightened early risk assessment and targeted prevention around the time of SLE diagnosis.
Reference: Moe SR, Haukeland H, Brunborg C, et al. Accrual of thromboembolic events and antiphospholipid syndrome in new-onset systemic lupus erythematosus: a population-based inception cohort study. RMD Open. 2025;11(3):e005795. doi: 10.1136/rmdopen-2025-005795.
