Task-related oxygen uptake during domestic activities of daily life in patients with COPD and healthy elderly subjects

ABSTRACTBackground Patients with COPD generally have a poor peak aerobic capacity and may therefore experience more inconvenience during domestic activities of daily life (ADLs). Yet, task-related oxygen uptake and symptom perception during ADLs have been studied rarely in COPD. It therefore remains unknown whether and to what extent differences may exist in task-related oxygen uptake and symptom perception during ADLs in COPD patients after stratification for gender, GOLD stage, MRC dyspnea grade or score on BODE index. Methods Ninety-seven COPD patients and 20 healthy subjects performed 5 self-paced domestic ADLs with 4-min rest intervals: putting on socks, shoes and vest; folding 8 towels; putting away groceries; washing up 4 dishes, cups and saucers; and sweeping the floor for 4 min. Task-related oxygen uptake was assessed using a mobile oxycon, while Borg scores were used to assess task-related dyspnea and fatigue. Results COPD patients used a significantly higher proportion of their peak aerobic capacity and ventilation to perform ADLs compared to healthy elderly subjects, accompanied by higher task-related Borg dyspnea scores. Patients with GOLD stage IV, MRC dyspnea grade 5 or BODE score of >/=6 points had the highest task-related oxygen uptake and dyspnea perception during the performance of domestic ADLs. Results showed no gender-related differences. Conclusion COPD patients experience a relatively high metabolic load and symptom perception during the performance of ADLs that is not the same as seen in their healthy peers, particularly in patients with GOLD stage IV, MRC dyspnea grade 5 or BODE score of >/=6 points