CO:11:4 | Unveiling frailty in active systemic lupus erythematosus in the modern era of rheumatology: first real-life use of the SLICC-FI in a cohort diagnosed after 2000

Angela Elia¹, Dina Zucchi², Michele Moretti¹, Elena Elefante², Chiara Cardelli¹, Linda Carli², Viola Signorini², Chiara Stagnaro², Chiara Tani¹, Marta Mosca¹. | ¹U.O. di Reumatologia, Dipartimento di Medicina Clinica e Sperimentale, Università di Pisa; ²U.O Reumatologia, Azienza Ospedaliero Universitaria Pisana, Pisa, Italy

Background. In patients with active systemic lupus erythematosus (SLE), therapeutic decisions should consider frailty, which reflects disease activity, organ damage, and comorbidities. The SLICC Frailty Index (SLICC-FI) has proven useful in predicting mortality, damage accrual, and hospitalizations. This study applied the SLICC-FI in an active SLE cohort to estimate frailty prevalence and identify key clinical determinants.

Materials and Methods. This was a retrospective analysis of prospectively collected data from a monocentric SLE cohort fulfilling the 2019 EULAR/ACR classification criteria. Eligible patients were diagnosed after 2000 and had active disease requiring therapeutic modification. The SLICC-FI (FI) was calculated at study entry using a modified 37-item version (clinician-reported variables only). Based on FI score, patients were classified as robust (FI < 0.03), relatively less fit (0.03 < FI < 0.10), less fit (0.10 < FI< 0.21), or frail (FI > 0.21). Demographic, clinical, and serological data were collected.

Results. A total of 119 patients were included (94.1% female; mean age 37.1 ± 10.7 years; median disease duration 12 years IQR). At study entry, median SLEDAI was 8 (IQR), median SLICC was 1 (range 1–4); median daily dose of glucocorticoids (GC) was 4 mg (IQR). The mean FI was 0.20 ± 0.08; 5.9% (7/119) were relatively less fit, 53.8% (64/119) less fit, and 40.3% (48/119) frail, no patients were categorized as robust. The most important determinants of frailty in frail patients are shown in Figure 1. No differences emerged between frail and non-frail patients in age at diagnosis, disease duration, SLICC, SLEDAI, or baseline steroid dose. Regarding cumulative organ involvement, kidney (p=0.028), articular (p=0.023), constitutional (p=0.006), and pulmonary (p=0.005) systems were significantly more affected in frail patients. Frail patients were more frequently SSA-positive (p=0.025), SSB-positive (p=0.007), and had more overlap syndromes (Sjogren or APS; p=0.04), but not more Sjogren’s diagnoses. Other autoantibody profiles did not differ. Comorbidities were more frequent among frail patients (p=0.013), although fibromyalgia prevalence was similar. No differences emerged in the number of immunosuppressants used during the disease history; however, all patients with more than four therapy changes were frail, particularly those treated with MMF (p=0.008) and MTX (p=0.41). Other analyses are shown in Figure 2.

Conclusions. Application of the SLICC-FI in a real-life active SLE cohort revealed a high prevalence of frailty, also in patients with a relatively recent disease history and treated with more recent therapeutic approaches. This tool allows comprehensive assessment of clinical vulnerability and may assist therapeutic decisions in complex cases. Further analyses are ongoing to evaluate its prognostic value for treatment response and long-term outcomes.