Fatigue in patients with antineutrophil cytoplasmic antibody-associated vasculitis was associated with heightened perception of exertion, depression, anxiety and sleep disturbance but normal muscle and cardiorespiratory function, according to results from international investigators.
Researchers used the Multidimensional Fatigue Inventory (MFI-20) and focused on its physical component to measure fatigue in 48 patients with antineutrophil cytoplasmic antibody-associated vasculitis or ANCA-associated vasculitis and 41 healthy controls. They also assessed quality of life, anxiety/depression and sleep quality with validated questionnaires and used superimposed electrical stimulation to assess voluntary muscle activation. Dual-energy X-ray absorptiometry scans were used to measure muscle mass, and researchers also measured cardiorespiratory fitness and perceived exertion during progressive submaximal exercise.
Compared with the controls, results showed elevated physical fatigue scores in patients with ANCA-associated vasculitis. Although both groups had the same muscle mass, researchers noted patients with ANCA-associated vasculitis had lower maximal voluntary contraction and time to failure in the endurance test due to reduced voluntary activation. Results also showed both groups had the same estimated maximum oxygen uptake and oxygen pulse.
Higher ratings of perceived exertion were reported by patients with ANCA-associated vasculitis for the same relative workload as healthy controls, based on the results. The higher exertion ratings, as well as the depression, anxiety and sleep disturbance factors correlated with fatigue results on the MFI-20, researchers noted. – by Casey Tingle
Disclosure: The researchers report no relevant financial disclosures.