The Post-COVID-19 Haul on Pulmonary Function: A Prospective Cross-Sectional Study

Abstract

Background: Long COVID syndrome, characterized by symptoms like dyspnea, fatigue, and cough, persisting for weeks to months after the initial SARS-CoV-2 infection, poses significant challenges globally. Studies suggest a potential higher risk among females aged 40-50, with symptoms affecting individuals regardless of initial COVID-19 severity, underscoring the need for comprehensive understanding and management.

Methods: A prospective longitudinal study was conducted at a teaching tertiary care institute in Central India, involving COVID-19 patients from May 2020 to September 2021. Participants, aged 18 or older, diagnosed with COVID-19 and surviving until the last follow-up, were monitored telephonically and during outpatient visits for treatment details and outcomes. Data analysis was done using R software 4.2.1.

Results: The baseline characteristics of the study participants showed a majority of moderate COVID-19 severity (47.5%), with a higher proportion of males (64.8%) affected. Common comorbidities included diabetes (27.1%) and hypertension (22.9%). Long COVID-19 symptoms, notably breathlessness, were prevalent, with females exhibiting a significantly higher association. Pulmonary function abnormalities were associated with both long COVID-19 symptoms and higher COVID-19 severity categories, indicating lasting respiratory impact post-infection.

Conclusion: Long after the pandemic, COVID-19 continues to raise concerns due to persistent sequelae, with a majority experiencing long COVID symptoms, particularly those with severe initial illness, including breathlessness and abnormal lung function, highlighting prevalent restrictive lung pattern changes.

Keywords: coronavirus; covid-19; long covid syndrome; post-acute covid-19 syndrome; pulmonary function test; respiratory function tests.

Figure 1. Flow diagram showing study population recruitment and assessment for various parameters.

Figure 2. Comparison violin plot comparing PFT parameters with mMRC grades.

X-axis: mMRC grades, Y-axis: a) FEV1, b) FEV1 percent predicted, c) FVC, and d) FVC percent. MMRC grade 0 (n =120, coded in green round dots), MMRC grade 1 (n =36, coded in orange round dots), MMRC grade 2 to 4 (n = 36, coded in purple round dots). a) Left-top image shows the FEV1 values. b) Right-top image shows the FEV1 percent predicted values. c) Left bottom shows the FVC values. d) Right bottom shows the FVC percent predicted values along the y-axis with all their mean values as red dots.

Figure 3. Comparison violin plot comparing PFT parameters with COVID-19 severity grades.

X-axis: WHO COVID-19 severity grades, Y-axis: a) FEV1, b) FEV1 percent predicted, c) FVC, and d) FVC percent. COVID-19 severity category 0 (n = 30, coded in green round dots), COVID-19 severity category 2 (n = 10, coded in green round dots), and COVID-19 severity categories 3-4 (n = 7, coded in green round dots). a) Left-top image shows the FEV1 values. b) Right-top image shows the FEV1 percent predicted values. c) Left bottom shows the FVC values. d) Right bottom shows the FVC percent predicted values along the y-axis with all their mean values as red dots.