Incidence and risk of arterial and venous thrombotic events in Systemic Lupus Erythematosus patients: a population-based study

Objectives: Current data on arterial and venous thrombotic events (ATE and VTE) and cardiovascular (CV) risk management in the European systemic lupus erythematosus (SLE) population are limited. This study aimed to investigate the incidence and risk of thrombotic events and all-cause death in an Italian SLE cohort over the past decade, along with its pharmacotherapy. Methods: Incident SLE cases between 2010 and 2019 were identified using administrative health databases of the Lombardy Region. The association between SLE and outcomes, compared with age- and sex-matched controls, was reported as incidence rate per 1000 person-years (PY) and as adjusted hazard ratios (HR) with 95% confidence intervals. Results: Overall, 2133 SLE patients and 21 283 no-SLE individuals were included. A higher incidence rate of ATE (4.22 vs 2.26 per 1000 PY), VTE (1.85 vs 0.67 per 1000 PY) and all-cause death (15.18 vs 6.22 per 1000 PY) was reported in SLE patients than in those without (P < 0.0001) as well as an increased risk of ATE (HR, 1.65; 95% CI: 1.20, 2.26), VTE (HR, 2.25; 95% CI: 1.35, 3.74) and all-cause death (HR, 1.81; 95% CI: 1.52, 2.15). After SLE diagnoses, hydroxychloroquine and glucocorticoids were prescribed for at least 60% of patients. Additionally, a higher exposure to cardiovascular medications was also seen in SLE patients. Conclusion: Our findings confirmed higher risks of ATE, VTE and all-cause death in SLE patients. While increased CV medication use after SLE diagnoses suggests heightened awareness to CV risk profile, more attention is required to balance SLE disease activity with minimizing exposure to drugs associated with exacerbating CV risk.