Sarcopenia and its clinical correlation in elderly chronic obstructive pulmonary disease: a prospective cohort study.

The aim of this study was to examine the effects of sarcopenia on clinical characteristics and short-term outcomes in elderly chronic obstructive pulmonary disease (COPD) patients.One hundred twenty elderly COPD patients (age>60) recruited from Beijing Shijingshan Hospital were divided into sarcopenia and non-sarcopenia groups according to the severity of sarcopenia at the first admission. Baseline data, geriatric syndrome, laboratory indicators and body composition analysis were analyzed. One year followed-up by outpatient visits was focused on clinical characteristics and telephone follow-ups for collecting all-cause deaths and acute exacerbations of chronic obstructive pulmonary disease as end-point events. The risk factors for sarcopenia were analyzed by univariate analysis and multivariate logical regression. The proportional hazards model (COX) regression was performed to determine the effect of sarcopenia on COPD patients' prognoses.One hundred twenty patients (76 men and 44 women) with an average age of 76.7±8.78 years were included, of which 63 patients (52.5%) were diagnosed with sarcopenia. Compared to the non-sarcopenia group, the sarcopenia group exhibited worse lung function and more severe geriatric syndromes with significantly higher incidence ratios of somnipathy and frailty. The sarcopenia group also showed worse muscle indicators and declined body composition. Multivariate analysis showed that the occurrence of sarcopenia in elderly COPD patients was correlated with forced expiratory volume in the first second (FEV1) (OR=0.97, 95% CI: 0.94-1.0, p=0.035), body mass index (BMI) (OR=0.80, 95% CI: 0.71-0.89, p=0.035) and hemoglobin (OR=0.98, 95% CI: 0.96-1.0, p=0.023). Furthermore, the COX regression indicated the association of sarcopenia with acute exacerbations of COPD within the follow-up period (HR=2.4, 95% CI: 1.01-5.72, p=0.048).Sarcopenia increases the risk of acute exacerbations of chronic obstructive pulmonary disease in the elderly. Sarcopenia incidence in elderly COPD is associated with FEV1, BMI, and hemoglobin and closely monitoring indicators is useful for early diagnosis of sarcopenia.