Hospital and Intensive Care Unit Stay Associated with Body Mass Index Affect Cardiorespiratory Fitness in Patients with COVID-19.

Background: The effects of coronavirus disease 2019 (COVID-19) on the cardiorespiratory fitness of hospitalized and obese patients are of utmost relevance. This study aimed to analyze how hospital and intensive care unit (ICU) stay together with body mass index affect cardiorespiratory fitness in patients with COVID-19. Methods: 251 participants (males, n = 118; females, n = 133) were assigned to four groups: non-hospitalized COVID-19 patients (n = 65, age: 45.3 years), hospitalized COVID-19 patients (n = 63, age: 57.6 years), COVID-19 patients admitted to the ICU (n = 61, age: 56.9 years), and control group (n = 62, age: 49.8 years). An incremental cardiopulmonary exercise test was performed between 3 and 6 weeks after medical discharge from hospital. Results: Higher peak oxygen uptake (VO2peak), ventilatory efficiency and power output were found in ICU patients with normal weight (NW) than in overweight (OW) (Mean difference: 0.1 Lmin(-1), -5.5, 29.0 W, respectively) and obese (OB) ICU patients (Mean difference: 0.1 Lmin(-1), -5.0, 26.2 W, respectively) (p < .05). In NW, OW and OB participants, higher VO2peak and power output were observed in control group compared with non-hospitalized (Mean difference: NW: 0.2 Lmin(-1), 83.3 W; OW: 0.2 Lmin(-1), 60.0 W; OB: 0.2 Lmin(-1), 70.9 W, respectively), hospitalized (Mean difference: NW: 0.2 Lmin(-1), 72.9 W; OW: 0.1 Lmin(-1), 58.3 W; OB: 0.2 L center dot min(-1), 91.1 W, respectively) and ICU patients (Mean difference: NW: 0.1 Lmin(-1), 70.9 W; OW: 0.2 Lmin(-1), 91.1 W; OB: 0.3 Lmin(-1); 65.0 W, respectively) (p < .05). Conclusions: The degree of severity of COVID-19, especially identified by hospitalization and ICU stay, together with obesity and overweight were key factors in reducing cardiorespiratory fitness in patients with COVID-19.