Poor muscle strength and function in physically inactive childhood-onset systemic lupus erythematosus despite very mild disease

Poor muscle strength and function in physically inactive childhood-onset systemic lupus erythematosus despite very mild disease

Advances in Rheumatology, August 2016

27914598

Ana Jéssica Pinto, Fabiana Braga Benatti, Hamilton Roschel, Ana Lúcia de Sá Pinto, Clovis Artur Silva, Adriana Maluf Elias Sallum, Bruno Gualano

To compare muscle strength (i.e. lower- and upper-body strength) and function between physically inactive childhood-onset systemic lupus erythematosus patients (C-SLE) and healthy controls (CTRL). This was a cross-sectional study and the sample consisted of 19 C-SLE (age between 9 and 18 years) and 15 CTRL matched by age, sex, body mass index (BMI), and physical activity levels (assessed by accelerometry). Lower- and upper-body strength was assessed by the one-repetition-maximum (1-RM) test. Isometric strength was assessed through a handgrip dynamometer. Muscle function was evaluated by the timed-stands test (TST) and the timed-up-and-go test (TUG). When compared with CTRL, C-SLE showed lower leg-press and bench-press 1-RM (p=0.026 and p=0.008, respectively), and a tendency toward lower handgrip strength (p=0.052). C-SLE showed lower TST scores (p=0.036) and a tendency toward higher TUG scores (p=0.070) when compared with CTRL. Physically inactive C-SLE patients with very mild disease showed reduced muscle strength and functionality when compared with healthy controls matched by physical activity levels. These findings suggest C-SLE patients may greatly suffer from a physically inactive lifestyle than healthy controls do. Moreover, some sub-clinical "residual" effect of the disease or its pharmacological treatment seems to affect C-SLE patients even with a well-controlled disease.