Fatigue independently associated with disease activity in SLE

A recent study found that Fatigue and disease activity are independent factors as found using the Physician Global Assessment (PGA). The study was published in the journal RMD Open Rheumatic & Musculoskeletal Diseases. 

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease, showing a broad spectrum of clinical manifestations, having a relapsing-remitting course, and can affect various organs or systems. Fatigue is one of the challenging manifestations of systemic lupus erythematosus. As it is not known if fatigue and disease activity are interdependent factors, researchers conducted a study to analyze if reported fatigue may bias the assessment of disease activity in SLE according to the Physician Global Assessment (PGA). 

Data were collected from patients from the Lupus BioBank of the upper Rhein database. A cross-sectional multicenter collection of detailed clinical and biological data was used. Participants had to fulfill the 1997 American College of Rheumatology criteria for SLE and the PGA (0–3 scale). Fatigue was assessed according to the Fatigue Scale for Motor and Cognitive Functions. Univariate and multivariate regression models were built to determine which variables were associated with the PGA. 

Findings: 

• A total of 350 patients were included.
• Of the total,89% were female with a median age of 42 years. 
• The median Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score was 4 (IQR: 2–6).
• Of these 350 patients, 257 (73%) reported significant fatigue.
• The PGA was significantly associated with fatigue but not the SELENA-SLEDAI.
• Both fatigue and SELENA-SLEDAI were independently associated with the PGA in two different multivariate models. 

Thus, the researchers concluded that Fatigue is independently associated with disease activity assessed using the PGA. To improve the reliability, they also suggested that the PGA should capture only objectively active disease manifestations. 

For further reading: 10.1136/rmdopen-2022-002395

Mertz P, Piga M, Chessa E, et al. Fatigue is independently associated with disease activity assessed using the Physician Global Assessment but not the SLEDAI in patients with systemic lupus erythematosus. RMD Open. 2022;8(2):e002395.