Physical function and muscle strength in sporadic inclusion body myositis

Abstract

Introduction: In this study, self-reported physical function, functional capacity, and isolated muscle function were investigated in sporadic inclusion body myositis (sIBM) patients. Methods: The 36-item Short Form (SF-36) Health Survey and 2-min walk test (2MWT), timed up & go test (TUG), and 30-s chair stand performance were evaluated. In addition, patients were tested for knee extensor muscle strength (isokinetic dynamometer) and leg extension power (Nottingham power rig). Results: TUG performance was the strongest predictor of selfreported physical function (r 2 5 0.56, P < 0.05). Knee extension strength and between-limb strength asymmetry were the strongest multi-regression indicators of TUG performance (r 2 5 0.51, P < 0.05). Strength asymmetry showed the strongest single-factor (negative) association with 2MWT performance (r 2 5 0.49, P < 0.05). Discussion: TUG assessment appears to sensitively predict self-perceived physical function in sIBM patients. Notably, between-limb asymmetry in lower limb muscle strength had a substantial negative impact on motor tasks involving gait function.

The immune system in sporadic inclusion body myositis patients is not compromised by blood-flow restricted exercise training

“…Recruited patients were randomly allocated to the intervention group (BFRE) or the control group (CON), by using a 1:1 random allocation ratio design. Recruitment procedures, testing and training of patients have been described in detail elsewhere [38]. In brief, a total of 22 biopsy-validated [3] sIBM patients (Table 1) were recruited (for detailed overview of study design, see Fig.…”

“…The BFRE training protocol has been described in detail elsewhere [38]. In brief, the exercise protocol consisted of low-load (~ 25RM) blood-flow occluded resistance training performed two times per week for 12 weeks, involving five different lower extremity exercises (three to four sets of each exercise).…”

Update on outcome assessment in myositis

“…In neuromuscular disorders, several timed tests have been used in therapeutic trials or observational studies to assess muscle function, endurance, and fatigability. In addition to the FI-2 3,38 , they include the 2- and 6-minute walking distance test (2/6MWDT) 39 , timed 10-meter walk/run test 40 , timed up-and-go test (TUG) 39,41,42 , 30-second chair stand test (30s-CST) 43,44 , and Short Physical Performance Battery (SPPB) 45,46 (Table 4). Except for the 6MWDT, these tests have not been validated in adult or juvenile myositis.…”

Challenges in diagnosis and treatment of sporadic inclusion-body myositis

“…11 Furthermore, the time to stand up and start the movement was the prognostic factor in patients with sIBM. 12 The cause of the disease is still not fully understood. So far, the proposed theories suggest a role in the etiology of disease of: viral infection, accumulation of toxic proteins, the autoimmune attack, degeneration of muscle cells (rimmed vacuoles filled with nuclear and lysosomal proteins, and inclusions in the cytoplasm of muscle cells composed of the TDP-43 (TAR DNA-binding protein 43) ( Fig.…”