Impact of Body Composition and Sarcopenia on Mortality in Chronic Obstructive Pulmonary Disease Patients

Abstract

Background: Patients with chronic obstructive pulmonary disease (COPD) have alterations in body composition, such as low cell integrity, body cell mass, and disturbances in water distribution evidenced by higher impedance ratio (IR), low phase angle (PhA), as well as low strength, low muscle mass, and sarcopenia. Body composition alterations are associated with adverse outcomes. However, according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), the impact of these alterations on mortality in COPD patients is not well-established. Our aims were to evaluate whether low strength, low muscle mass, and sarcopenia impacted mortality in COPD patients.

Methods: A prospective cohort study performance was conducted with COPD patients. Patients with cancer, and asthma were excluded. Body composition was assessed by bioelectrical impedance analysis. Low strength and muscle mass, and sarcopenia were defined according to EWGSOP2.

Results: 240 patients were evaluated, of whom 32% had sarcopenia. The mean age was 72.32 ± 8.24 years. The factors associated with lower risk of mortality were handgrip strength (HR:0.91, CI 95%; 0.85 to 0.96, p = 0.002), PhA (HR:0.59, CI 95%; 0.37 to 0.94, p = 0.026) and exercise tolerance (HR:0.99, CI 95%; 0.992 to 0.999, p = 0.021), while PhA below the 50th percentile (HR:3.47, CI 95%; 1.45 to 8.29, p = 0.005), low muscle strength (HR:3.49, CI 95%; 1.41 to 8.64, p = 0.007) and sarcopenia (HR:2.10, CI 95%; 1.02 to 4.33, p = 0.022) were associated with a higher risk of mortality.

Conclusion: Low PhA, low muscle strength, and sarcopenia are independently associated with poor prognosis in COPD patients.

Keywords: COPD; body composition; impedance ratio; mortality; muscle mass; phase angle; strength.

Figure 1

Kaplan–Meier curves for all cause death.