Journal Article

Identifying a Heart Rate Recovery Criterion After a 6-Minute Walk Test in COPD

Adami, Alessandra, Jendzjowsky, Nicholas G, MacDonald, David M, Zhao, Dongxing, Rossiter, Harry B, Bowler, Russell P, Make, Barry J, Kunisaki, Ken M, Casaburi, Richard, Abbasi, Asghar, Tiller, Nicholas B, Porszasz, Janos, Stringer, William W, Yee, Christopher, Yuan, Wei

2021

Overview

Slow heart rate recovery (HRR) after exercise is associated with autonomic dysfunction and increased mortality. What HRR criterion at 1-minute after a 6-minute walk test (6MWT) best defines pulmonary impairment?. A total of 5008 phase 2 COPDGene (NCT00608764) participants with smoking history were included. A total of 2127 had COPD and, of these, 385 were followed-up 5-years later. Lung surgery, transplant, bronchiectasis, atrial fibrillation, heart failure and pacemakers were exclusionary. HR was measured from pulse oximetry at end-walk and after 1-min seated recovery. A receiver operator characteristic (ROC) identified optimal HRR cut-off. Generalized linear regression determined HRR association with spirometry, chest CT, symptoms and exacerbations. HRR after 6MWT (bt/min) was categorized in quintiles: ≤5 (23.0% of participants), 6-10 (20.7%), 11-15 (18.9%), 16-22 (18.5%) and ≥23 (18.9%). Compared to HRR≤5, HRR≥11 was associated with (p<0.001): lower pre-walk HR and 1-min post HR; greater end-walk HR; greater 6MWD; greater FEV %pred; lower airway wall area and wall thickness. HRR was positively associated with FEV %pred and negatively associated with airway wall thickness. An optimal HRR ≤10 bt/min yielded an area under the ROC curve of 0.62 (95% CI 0.58-0.66) for identifying FEV <30%pred. HRR≥11 bt/min was the lowest HRR associated with consistently less impairment in 6MWT, spirometry and CT variables. In COPD, HRR≤10 bt/min was associated with (p<0.001): ≥2 exacerbations in the previous year (OR=1.76[1.33-2.34]); CAT≥10 (OR=1.42[1.18-1.71]); mMRC≥2 (OR=1.42[1.19-1.69]); GOLD 4 (OR=1.98[1.44-2.73]) and GOLD D (OR=1.51[1.18-1.95]). HRR≤10 bt/min was predicted COPD exacerbations at 5-year follow-up (RR=1.83[1.07-3.12], P=0.027). HRR≤10 bt/min after 6MWT in COPD is associated with more severe expiratory flow limitation, airway wall thickening, worse dyspnoea and quality of life, and future exacerbations, suggesting that an abnormal HRR≤10 bt/min after a 6MWT may be used in a comprehensive assessment in COPD for risk of severity, symptoms and future exacerbations.

• Publisher: Dove Medical Press Limited,Dove Medical Press Ltd,Dove Press,Dove,Dove Medical Press
• Subject: Atrial fibrillation / autonomic dysfunction / Body mass index / Carbon monoxide / Cardiac arrhythmia / Cardiovascular disease / chest computed tomography / Chronic obstructive pulmonary disease / COPD exacerbation / Dyspnea / exercise / Forced Expiratory Volume / Heart / Heart beat / Heart failure / Heart Rate / Humans / Lung / Lung diseases / Lung diseases, Obstructive / Medical imaging / Mortality / Original Research / Oximetry / Pharmaceutical industry / Pulmonary Disease, Chronic Obstructive - diagnosis / Quality of Life / Spirometry / United Kingdom / Variables / Walk Test