Role of the one-minute sit-to-stand test in the diagnosis of post COVID-19 condition: a prospective cohort study

OBJECTIVE: To analyze the relationship between one-minute sit-to-stand test (1MSTST) parameters and a diagnosis of post COVID-19 condition in a cohort of patients who previously had COVID-19. METHODS: This was a prospective cohort study of patients with post COVID-19 condition referred for body plethysmography at a tertiary university hospital. Post COVID-19 condition was defined in accordance with the current WHO criteria. RESULTS: Fifty-three patients were analyzed. Of those, 25 (47.2%) met the clinical criteria for post COVID-19 condition. HR was lower in the patients with post COVID-19 condition than in those without it at 30 s after initiation of the 1MSTST (86.2 ± 14.3 bpm vs. 101.2 ± 14.7 bpm; p < 0.001) and at the end of the test (94.4 ± 18.2 bpm vs. 117.3 ± 15.3 bpm; p < 0.001). The ratio between HR at the end of the 1MSTST and age-predicted maximal HR (HR(end)/HR(max)) was lower in the group of patients with post COVID-19 condition (p < 0.001). An HR(end)/HR(max) of < 62.65% showed a sensitivity of 78.6% and a specificity of 82.0% for post COVID-19 condition. Mean SpO(2) at the end of the 1MSTST was lower in the patients with post COVID-19 condition than in those without it (94.9 ± 3.6% vs. 96.8 ± 2.4%; p = 0.030). The former group of patients did fewer repetitions on the 1MSTST than did the latter (p = 0.020). CONCLUSIONS: Lower SpO(2) and HR at the end of the 1MSTST, as well as lower HR at 30 s after initiation of the test, were associated with post COVID-19 condition. In the appropriate clinical setting, an HR(end)/HR(max) of < 62.65% should raise awareness for the possibility of post COVID-19 condition.