Which functional outcome measures can we use as a surrogate for exercise capacity during remote cardiopulmonary rehabilitation assessments? A rapid narrative review

Introduction The COVID-19 pandemic has seen many cardiopulmonary rehabilitation services delivering programmes remotely. One area of concern is how to assess exercise capacity when a supervised exercise test is not possible. The aim of this review was to examine the relationship between functional exercise tests with recommended exercise tests for cardiopulmonary rehabilitation.

Methods Rapid narrative review. Searches were conducted by 2 authors.

Participants: Adults, all long-term conditions.

Intervention: Any/none.

Outcome: Duke activity status index (DASI), Sit to stand (STS 30 s, 1 min and 5 repetition), short physical performance battery (SPPB), 4 metre gait speed (4MGS) or step test (Chester/others) AND directly compared to one of the recommended exercise tests for cardiopulmonary rehabilitation: 6 min walk test (6 MWT), incremental shuttle walk test (ISWT) or cardiopulmonary exercise test (CPET) in terms of reporting agreement/correlation.

Study design: primary research only, controlled trials or observational studies.

Results 16 articles (249 screened). N=2271 patients. Overall there was weak-strong correlations for the included tests with a recommended exercise test r=0.38–0.85. There were few reported issues with feasibility or safety of the tests. However all tests were supervised in a clinical setting. The test that correlated highest with field walking test was the 4MGS with the ISWT (r=0.78) and with the 6 MWT (r=0.85).

Discussion The 4MGS correlates highest with routine measures of exercise tolerance. However it may be difficult to standardise in a remote assessment or prescribe exercise from. Clinicians should strive for face-to-face standardised exercise tests where possible to be able to guide exercise prescription.