Impact of exacerbations of cystic fibrosis on muscle strength

Abstract

BackgroundAdult patients with cystic fibrosis have peripheral muscle weakness, which is related to exercise intolerance and poor prognosis. The influence of acute exacerbations on muscle strength has been poorly studied. This study aimed to investigate whether quadriceps force (QF), as assessed with an involuntary technique, changes during intravenous antibiotics therapy (IVAT) for an exacerbation.MethodsQF was measured in 20 patients using twitch stimulation of the femoral nerve at the day of hospitalization (day 1) and at termination (day 14) of the IVAT. Physical activity was monitored during IVAT using a SenseWear armband. Ten stable patients served as control subjects.ResultsQF did not change during exacerbation (potentiated twitch force at day 1: 140 ± 42 N, at day 14: 140 ± 47 N), but a decrease was observed in individual patients. Changes in twitch force during exacerbation were correlated with time spent in activities of at least moderate intensity (r = 0.61, p = 0.007).ConclusionsQF does not systematically decrease during exacerbations of cystic fibrosis. Individual changes in QF are well correlated with daily time spent in activities of at least moderate intensity.

Skeletal muscle contractility and fatigability in adults with cystic fibrosis

“…Many factors may potentially contribute to reduced muscle CSA in CF, such as inflammation [18], medication [19], repeated exacerbations [20], altered nutritional status [7] or physical inactivity [6]. In our study, we only found a slight tendency for reduced qCSA in CF (14%), which is consistent with previous findings in more severe patients (14%, P = 0.05) [18].…”

Physical activity assessment in cystic fibrosis: A position statement

“…a Within CF able to discriminate between exacerbation and stable patients. a [2,20] Evidence of significant correlation with exercise capacity a , strength a , bone mineral density a , kyphosis a , and lung function a [2,[20][21][22] Evidence of responsiveness to IVAB a . [18,20,23] ActiGraph Evidence of responsiveness to IVAB a .…”

“…a [2,20] Evidence of significant correlation with exercise capacity a , strength a , bone mineral density a , kyphosis a , and lung function a [2,[20][21][22] Evidence of responsiveness to IVAB a . [18,20,23] ActiGraph Evidence of responsiveness to IVAB a . [24,25] Evidence of correlation with the HAES and the 7 day PAR questionnaires and the Bratteby activity diary a, b,c [24,25] Within CF able to discriminate between gender a, b, c and disease severity b, c [15,24] Evidence of significant correlation with exercise capacity a, b, c [3] Evidence of responsiveness to a physical conditioning program a, b, c [5] RT3 Evidence of significant correlation with step rate/count and respiratory symptoms diary and lung function a, b [29] Evidence of responsiveness to IVAB a, b [29] a Adults.…”

Longitudinal relationship between physical activity and lung health in patients with cystic fibrosis

“…Similarly to the recruitment process, if a patient was not well enough to engage in their regular HPA, their data collection was postponed until a visit at which their typical HPA patterns had resumed, to control for potential losses in muscle force, and the documented reductions in HPA during exacerbation [16]. As a result, the number of data points varied among patients for the study period.…”