Associations of Post-Acute COVID syndrome with physiological and clinical measures 10 months after hospitalization in patients of the first wave

Abstract

Background: For a better understanding of the factors underlying the Post-Acute COVID Syndrome, we studied the relationship between symptoms and functional alterations in COVID-19 patients 10 months after hospitalization.

Methods: One-hundred-one patients hospitalized between March 1st and June 30th 2020 participated in a follow-up visit for an assessment of clinical history, comorbidities, lung function, physical capacity and symptoms, including the SGRQ for health-related quality of life, PHQ-9-D for depression, and SOMS-2 J for somatoform disorders. Data were analyzed by univariate comparisons and multiple logistic regression analyses.

Results: Median age was 60 years, 42% were female, 76% had at least one comorbidity, the median length of the hospital stay was 8 days, 19% had been on the ICU. The most prevalent symptoms included shortness of breath (49%), fatigue (49%) and cognitive impairment (39%). Signs of major depression (PHQ-9-D ≥ 10) occurred in 28%/2% (p < 0.05) of patients with/without self-reported cognitive impairment, with median total SGRQ score being 25.4/5.3 (p < 0.05). There were associations between shortness of breath and BMI, SGRQ and hemoglobin levels; between fatigue, SGRQ and PHQ-9-D; and between cognitive impairment and PHQ-9-D (p < 0.05 each) but not with lung function or physical capacity. Characteristics of the acute disease were not related to symptoms.

Conclusions: The findings demonstrate that 10 months after discharge from a hospital stay due to COVID-19, the percentages of patients with symptoms were high. Symptoms showed a consistent pattern but could not be attributed to altered lung function or physical capacity. Our results suggest a role for alternative etiologies including psychosocial factors.

Keywords: Depression; HrQoL; Lung function; Post-Acute COVID Syndrome; Somatization; Symptoms.

Fig. 1

Frequency of symptoms (absolute numbers) in the 101 participants of the follow-up visit. Due to the fact that the total number was n = 101, the numerical values of percentages are virtually the same. Data are given separately for males (blue) and females (red).

Fig. 2

Percentages of patients in the follow-up visit (n = 101) showing specific counts of symptoms (red) or abnormal values according to LLN or ULN for lung function and physical performance (blue). SpO₂ = oxygen saturation from pulse oximetry, FEV₁ = forced expiratory volume in 1 s, TLC = total lung capacity, 6-MWD = 6 min walk distance, LLN = lower limit of normal. For functional measures, percentages were in the range of 5% that is expected by definition in a normal population, except for FEV₁, possibly because of the fact that about 10% of patients had a history of obstructive airway disease.

Fig. 3A

Box plots of functional measures in percent predicted, or percentages for SpO₂ and FEV₁/FVC, for the two groups of patients either reporting or not reporting shortness of breath at the follow-up visit. SpO₂ = oxygen saturation from pulse oximetry, FEV₁ = forced expiratory volume in 1 s, FVC = forced vital capacity, TLC = total lung capacity, RV = residual capacity, 6-MWD = 6 min walk distance. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. In none of the measures there were statistically significant differences between the two groups (Mann-Whitney U-test).

Fig. 3B

Box plots of functional measures in percent predicted, or percentages for SpO₂ and FEV₁/FVC, for the two groups of patients either reporting or not reporting fatigue at the follow-up visit. SpO₂ = oxygen saturation from pulse oximetry, FEV₁ = forced expiratory volume in 1 s, FVC = forced vital capacity, TLC = total lung capacity, RV = residual capacity, 6-MWD = 6 min walk distance. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. In none of the measures there were statistically significant differences between the two groups (Mann-Whitney U-test).

Fig. 3C

Box plots of functional measures in percent predicted, or percentages for SpO₂ and FEV₁/FVC C, for the two groups of patients either reporting or not reporting cognitive impairment at the follow-up visit. SpO₂ = oxygen saturation from pulse oximetry, FEV₁ = forced expiratory volume in 1 s, FVC = forced vital capacity, TLC = total lung capacity, RV = residual capacity, 6-MWD = 6 min walk distance. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. In none of the measures there were statistically significant differences between the two groups (Mann-Whitney U-test).

Fig. 4A

Box plots of the scores of the PHQ-9-D and SGRQ (total and three sub-scores) for the two groups of patients either reporting or not reporting shortness of breath at the follow-up visit. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. There were statistically significant differences between the two groups (p < 0.05 each, Mann-Whitney U-test) for all of the scores.

Fig. 4B

Box plots of the scores of the PHQ-9-D and SGRQ (total and three sub-scores) for the two groups of patients either reporting or not reporting fatigue at the follow-up visit. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. There were statistically significant differences between the two groups (p < 0.05 each, Mann-Whitney U-test) for all of the scores.

Fig. 4C

Box plots of the scores of the PHQ-9-D and SGRQ (total and three sub-scores) for the two groups of patients either reporting or not reporting cognitive impairment at the follow-up visit. The boxes indicate the quartiles, the horizontal bar the median value, the whiskers the 10- and 90-percentiles, and the circles points outside of these. There were statistically significant differences between the two groups (p < 0.05 each, Mann-Whitney U-test) for all of the scores.