Cardiopulmonary Exercise Testing in patients with Long COVID: Evaluating functional capacity and exercise limitations

A recent study published by ScienceDirect (24/01/24) retrospectively analyzed cardiopulmonary exercise test (CPET) results in 169 patients with long COVID. The aim was to evaluate exercise capacity and changes from baseline to 1-year follow-up. Patients were tested 3 months or more after COVID-19 diagnosis.

At baseline, 36% had low VO2 peak, 46% had low maximum heart rate, and 54% had abnormal VO2/workload slope. Different parameters were abnormal in different patients, illustrating heterogeneity. Overall exercise capacity was reduced compared to predicted values.

At 1-year follow-up with 41 patients, there were no significant improvements in any CPET parameters. This matched patients’ self-reported lack of change in physical fitness levels.

The study found no evidence that deconditioning or ‘lack of effort’ explained the exercise limitations. Parameters related to respiratory disease were mostly normal. The abnormalities did not clearly point to one pathological mechanism.

The authors conclude long COVID patients show reduced exercise capacity on CPET, with different parameters affected across a heterogeneous group. There was no recovery at 1 year. CPET helps evaluate limitations and can inform potential treatments.

Study limitations include lack of pre-COVID baseline CPET data for comparison. The abnormalities may not be directly due to long COVID. Still, CPET provides useful objective data on exercise capacity in this patient group. Larger and longer-term studies are warranted.

You can read the full article here.

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