Sarcopenia in COPD patients: Prevalence, patients’ characteristics and predictive factors

INTRODUCTION Taking into consideration multifactorial origin of sarcopenia and extrapulmonary manifestations of chronic obstructive pulmonary disease (COPD), our study aimed to determine the prevalence and predictive factors for sarcopenia among COPD patients. METHODS We examined 190 patients with COPD in Ukraine and Poland using bioelectric impedance analysis, hand-grip dynamometry, 6MWT and several questionnaires to assess clinical characteristics of the patients. RESULTS Sarcopenia was detected in 25.3% of all patients with COPD. There was a significant difference between patients with and without sarcopenia in age, acute exacerbations of COPD, CAT, FEV1, BODE and CCI, Borg scope (post 6MWT), hand-grip strength, BMI, fat mass index, level of visceral fat, fat percentage, skeletal muscle index, gait speed, and 6MWT distance. According to regression analysis, factors related to sarcopenia were body mass index, visceral fat level, daily physical activity, percentage of fat and GOLD 3 airflow limitation. CONCLUSIONS Sarcopenia affected almost every fourth COPD patient and was associated with low BMI, high level of visceral fat and percentage of body fat, limited physical activity, and severe airflow limitation. Abbreviations 6MWT: the 6-minute walk test, BMI: body mass index, BODE index: body mass index, airflow obstruction, dyspnoea, exercise capacity index, CAT: the COPD assessment test, CCI: Charlson comorbidity index, COPD: chronic obstructive pulmonary disease, FEV1: forced expiratory volume in one second, mMRC: modified Medical Research Council, SaO2: oxygen saturation, SGRQ: St. George’s respiratory questionnaire. INTRODUCTION Chronic obstructive pulmonary disease (COPD) as a systemic disease is usually present with numerous comorbidities. One of the most common overlapping diseases is a skeletal muscle dysfunction. According to the GOLD 2020 Report, skeletal muscle dysfunction is characterized by loss of muscle cells and dysfunction of the remaining cells1. This definition is similar to the definition of the sarcopenia from the latest revision of European Working Group on Sarcopenia in Older People (EWGSOP2), according to which sarcopenia should be defined as low muscle strength combined with low muscle quantity or quality2. EWGSOP2 highlighted the role of sarcopenia as an important factor responsible for the impairment of daily physical activity, development of the cardiometabolic syndrome, and other complications. Presence of sarcopenia should be considered as being associated with an overall mortality and COPD-related mortality risk factor3, increased length of hospital stay, risk for hospitalization, lower probability of being discharged home4 and independently increasing hospital costs at hospital admission from 34% to 58.5% depending on the age of the population5. According to Goates et al.6, sarcopenia results in a great economic burden on the US healthcare system with total costs of hospitalizations amounting to more than US$ 19 billion6. Development of sarcopenia is a multifactorial process. EWGSOP2 determined factors that are related to the development of primary or secondary sarcopenia. According to EWGSOP2, the main cause for primary sarcopenia is ageing2. Secondary sarcopenia is caused by such factors as diseases, inactivity, and poor nutrition. But the structure of predictive factors for sarcopenia among patients with COPD is still not clear. Taking into account an increase in systemic inflammation during an acute exacerbation, extrapulmonary manifestations and comorbidities, and progressive airflow limitation, may result in physical inactivity and other comorbidities acting as separate factors for sarcopenia2. Our study aimed to determine the prevalence and predictive factors of sarcopenia development in COPD. AFFILIATION 1 Department of Propedeutics of Internal Medicine, National Pirogov Memorial Medical University, Vinnytsya, Ukraine 2 Department of Pneumonology in Katowice, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland 3 Department of Respiratory Medicine, Allergology and Pulmonary Oncology, Poznań University of Medical Sciences, Poznań, Poland CORRESPONDENCE TO Vitalii Poberezhets. Department of Propedeutic of Internal Medicine, National Pirogov Memorial Medical University, 56, Pirogova Str., 21018, Vinnytsya, Ukraine. E-mail: poberezhets_vitalii@vnmu.edu.ua