Characteristics and Related Factors of One-year Transition in Exercise Tolerance Following an Emergency Declaration due to the Coronavirus Disease 2019 Pandemic in Patients on Phase III Cardiac Rehabilitation.

OBJECTIVE

This study aimed to understand the long-term transition of exercise tolerance in patients on phase III cardiac rehabilitation (CR) and clarify the characteristics of patients with a high risk of declined exercise tolerance during the first emergency declaration.

METHODS

Patients who participated in phase III outpatient CR before the first emergency declaration and those who performed cardiopulmonary exercise testing were at ≥2-time points: before and at 3 or 12 months post-emergency declaration. Exercise tolerance transition at 3-time points was analyzed, and whether different social background factors affected the peak oxygen uptake (V̇O2) transition method remains to be examined.

RESULTS

A total of 101 (median age 74.0 years, 69% men), and both peak V̇O2 and anaerobic threshold (AT) significantly declined from pre-declaration to 3 months post-declaration but recovered to levels likely similar from pre-declaration at 12 months (peak V̇O2: from 17.3 to 16.7 to 18.7 mL/min/kg; AT: from 11.8 to 11.2 to 11.6 mL/min/kg). Further, patients with multiple comorbidities at pre-declaration had a significantly lower peak V̇O2 at 3 months (-1.0 mL/min/kg, p = 0.025) and it remained significantly low in those with a slower gait speed at 12 months after lifting the emergency declaration (-2.5 mL/min/kg, p = 0.009).

CONCLUSION

The emergency declaration declined the exercise tolerance in patients on phase III CR but improved to pre- declaration levels over time, but more likely declined in patients with multiple comorbidities during pre-declaration and those with low-gait speeds were less likely to improve their declined exercise tolerance.