D3.317 - Moderate-to-severe infections and initial SELENA-SLEDAI correlate with the incidence of flares in patients with Systemic Lupus Erythematosus

Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disorder characterised by significant diversity in clinical and immunological manifestations. The incidence of infections in adult patients SLE is elevated relative to the general population; nevertheless, only a limited number of studies have thus far attempted to evaluate a direct relationship between infectious occurrences, initial disease activity, and a potential rise in the Safety of Oestrogen in Lupus National Assessment - Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) in SLE patients.

A monocentric retrospective study utilising real-world data. Patients exhibiting non-adherence to therapy were eliminated to mitigate potential biases. An evaluation of their infectious events was conducted, specifically focusing on moderate-to-severe infections (fig.1), alongside their disease activity at diagnosis; thereafter, these were compared to a purported increase in disease activity in the subsequent 6 months, by evaluating the SELENA-SLEDAI. Simple linear regressions were employed to determine the association between each parameter and the SELENA-SLEDAI, utilising a 95% confidence interval (CI); subsequently, a multiple linear regression was conducted to evaluate the overall correlation with both parameters.

A total of one hundred and twenty-three patients (n=123) satisfied the inclusion criteria (fig. 2); of these, 86.99% were female (107 patients) and 13.01% were male (16 patients).The simple linear regression analysis between infectious events and SELENA-SLEDAI yielded a R² of 29.46% (p < 0.0001, y = 2.3552x + 2.3058, fig. 3); a less robust regression was noted with initial disease activity, presenting a R² of 16.12% (p = 0.006, y = 0.6212x + 2.9239, fig. 4). Finally, a multiple linear regression analysis was conducted, yielding a R² of 38.68% (p=0.0001, y = 2.0998x₁ + 0.4788x₂ + 1.5901)

This preliminary study demonstrated that real-life data is crucial for evaluating the influence of infections and initial disease activity on flare risk in patients with Systemic Lupus Erythematosus. Infections exhibited a significant correlation with an increase in SELENA-SLEDAI scores within 6 to 12 months post-event, while initial disease activity showed a less pronounced, yet significant, relationship with increased disease activity and flares. This study has some limitations, including a restricted number of included patients and varying definitions of infective episodes, necessitating further investigation for accurate assessment.