Reference equations for quadriceps function in COPD: a multicenter study

Abstract

In people with COPD lower-limb muscle dysfunction is characterized by a decrease in strength, endurance and power. The aim of the study is to develop quadriceps functions reference equations that can be used in COPD and to establish the clinical relevance. Method: Isometric strength as well as isokinetic endurance and power of quadriceps were assessed in 158 healthy subjects and 87 people with COPD. People with COPD also performed a 6 minutes walking test (6MWT) and a one-minute sit to stand test (1STS). Multiple linear regressions including age, sex, height and BMI as independent variables were conducted in healthy subjects. In COPD, correlations between predicted muscle function and 6MWT and 1STS were used to determine the clinical relevance of the equations. Results: Healthy subjects and people with COPD were 62±12 and 69±7 years old, had a height of 160±008 and 167±009 cm, a weight of 74.4±14.7 and 75.5±16.5 kg, and a BMI of 25.8±4.0 and 26.9±4.6 kg/m , respectively. The different equations are shown in Table 1. The correlation coefficients between muscle functions expressed as a percentage of the predicted value and 6MWT and 1STS performance were between 0.30 and 0.49 (p<0.05). Table 1: Reference equations of muscle function in healthy subjects 2 View inline 20-03-2023 13:58 Reference equations for quadriceps function in COPD: a multicenter study | European Respiratory Society https://erj.ersjournals.com/content/60/suppl_66/1204 2/5 Conclusion: In healthy subjects, age, sex, height and BMI predict around 70% of quadriceps muscle functions. In COPD, these equations correlate weakly to moderately with 6MWT and 1STS performance. COPD Peripheral muscle Diagnosis Footnotes Cite this article as Eur