TY - JOUR T1 - Intermuscular adipose tissue in patients with systemic lupus erythematosus JF - Lupus Science & Medicine JO - Lupus Sci Med DO - 10.1136/lupus-2022-000756 VL - 9 IS - 1 SP - e000756 AU - Jorge Luis Gamboa AU - Daniel Carranza-León AU - Rachelle Crescenzi AU - Michael Pridmore AU - Dungeng Peng AU - Adriana Marton AU - Annette Oeser AU - Cecilia P Chung AU - Jens Titze AU - Charles Michael Stein AU - Michelle Ormseth Y1 - 2022/11/01 UR - http://lupus.bmj.com/content/9/1/e000756.abstract N2 - Objective Patients with SLE frequently have debilitating fatigue and reduced physical activity. Intermuscular adipose tissue (IMAT) accumulation is associated with reduced physical exercise capacity. We hypothesised that IMAT is increased in patients with SLE and associated with increased fatigue, reduced physical activity and increased inflammation.Methods In a cross-sectional study, 23 patients with SLE and 28 control participants were evaluated. IMAT was measured in the calf muscles using sequential T1-weighted MRI. Patient-reported physical activity and fatigue were measured and a multiplex proteomic assay was used to measure markers and mediators of inflammation.Results IMAT accumulation (percentage of IMAT area to muscle area) was significantly higher in SLE versus control participants (7.92%, 4.51%–13.39% vs 2.65%, 1.15%–4.61%, median, IQR, p<0.001) and remained significant after adjustment for age, sex, race and body mass index (p<0.001). In patients with SLE, IMAT accumulation did not differ significantly among corticosteroid users and non-users (p=0.48). In the study cohort (patients and controls), IMAT was positively correlated with self-reported fatigue score (rho=0.52, p<0.001) and inversely correlated with self-reported walking distance (rho=−0.60, p<0.001). Several markers of inflammation were associated with IMAT accumulation in patients with SLE, and gene ontology analysis showed significant enrichment for pathways associated with macrophage migration and activation in relation to IMAT.Conclusion Patients with SLE have greater IMAT accumulation than controls in the calf muscles. Increased IMAT is associated with greater fatigue and lower physical activity. Future studies should evaluate the effectiveness of interventions that improve muscle quality to alleviate fatigue in patients with SLE.Data are available on reasonable request. All data relevant to the study are included in the article or uploaded as supplementary information. ER -