Role of acute exacerbations in skeletal muscle impairment in COPD

Abstract

Introduction: Muscle impairments are prevalent in COPD and have adverse clinical implications in terms of physical performance capacity, disease burden, quality of life and even mortality. During acute exacerbations of COPD (AECOPDs) the respiratory symptoms worsen and this might also apply to the muscle impairments. Areas covered: This report includes a review of both clinical and pre-clinical peer-reviewed literature of the past 20 years found in PubMed providing a comprehensive view on the role of AECOPD in muscle dysfunction in COPD, the putative underlying mechanisms and the treatment perspectives. Expert opinion: The contribution of AECOPD and its recurrent nature to muscle impairment in COPD cannot be ignored and can be attributed to the acutely intensifying and converging disease-related drivers of muscle deterioration, in particular disuse, systemic inflammation and corticosteroid treatment. The search for novel treatment options should focus on the AECOPD-enhanced drivers of muscle dysfunction as well as on the underlying, mainly catabolic, mechanisms. Considering the impact of AECOPD on muscle function, and that of muscle impairment on the recurrence of exacerbations, counteracting muscle deterioration in AECOPD provides an unprecedented therapeutic opportunity.

The association of blood urea nitrogen levels upon emergency admission with mortality in acute exacerbation of chronic obstructive pulmonary disease

“…Patients with pneumonia often have hydration status resulting in increasing reabsorption of urea by the kidneys, and elevation of BUN levels is frequently observed. 41 “Exacerbations” and the use of glucocorticoids enhance catabolism, 42 which increases the source of BUN. 43 However, the impact of these mechanisms should be evaluated with further studies.…”

Effect of targeted nutrient supplementation on physical activity and health-related quality of life in COPD: study protocol for the randomised controlled NUTRECOVER trial

“…We will investigate in an explorative analysis the relative effect of targeted nutrient supplementation on clinical outcome during a 4-week recovery phase after hospitalisation for a COPD exacerbation. First of all, because disturbances in the gut–muscle–brain axis as well as specific nutrient deficiencies might be affected by severe COPD exacerbations 3–6 37. Second, because the recovery period after severe COPD exacerbations is a completely neglected phase for nutritional interventions thus far 2.…”

“…During severe COPD exacerbations (requiring hospitalisation) disease-related detrimental factors such as systemic inflammation, hypoxia, physical inactivity, malnutrition and treatment with glucocorticoids and antibiotics, converge and intensify 2. Patients with frequent exacerbations constitute a specific disease phenotype with a worse prognosis, specifically a faster decline in lung function and muscle function, a greater worsening of health status and a substantial reduction in daily physical activity 3–6. In turn, physical inactivity drives further physical impairments, thereby increases the risk of recurrent exacerbations, leading to a vicious cycle of deterioration 6.…”

“…Patients with frequent exacerbations constitute a specific disease phenotype with a worse prognosis, specifically a faster decline in lung function and muscle function, a greater worsening of health status and a substantial reduction in daily physical activity 3–6. In turn, physical inactivity drives further physical impairments, thereby increases the risk of recurrent exacerbations, leading to a vicious cycle of deterioration 6. It is this circle that has to be broken and adapting a more healthy lifestyle may help achieving this.…”

“…Systemic inflammation and physical inactivity have also been identified as determinants of muscle mass loss in COPD 20–22. During an exacerbation, enhanced systemic inflammation and physical inactivity lead to acute muscle wasting, which may not be fully restored during recovery as there is evidence for an impaired regenerative potential in these patients 6. Disturbances of intestinal integrity manifested by increased GI permeability and alterations in intestinal fatty acid-binding protein (IFABP) have also been reported in COPD 11.…”