Two recent studies confirm lung scarring and other abnormalities occur in many COVID patients — even two years later. The studies were conducted at the Margaret Turner Warwick Center for Fibrosing Lung Disease with Iain Stewart, PhD. as corresponding author and at Tongji Medical College of Huazhong University and led by co-senior authors Qing Ye, MD, and Heshui Shi, MD, PhD.
The Chinese study looked retrospectively at 144 patients hospitalized with COVID between January 15 and March 10, 2020. Patients received three chest CT scans for inclusion in their research —at six months, 12 months, and 24 months after their COVID infection.
The UK study utilized follow-up CT chest scans from 209 patients discharged after hospitalization with COVID. These scans were completed within 8 months of discharge. Their purpose was to clarify the risk of residual lung disease among post-discharge COVID patients.
Their data confirms that those infected with severe COVID may experience permanent lung anomalies that could worsen with time. These patients may need to be followed, with the possibility of potential invention. Abnormalities may include:
- Cystic changes
- Dilation of the bronchi
- Other irregularities indicative of interstitial lung disease
Corresponding author Iain Stewart, PhD, from the UK, notes, “For some people, these fibrotic patterns may be stable or resolve, while for others, they may lead to long-term lung fibrosis progression, worsening quality of life and decreased life expectancy. Earlier detection of progression is essential to improving outcomes.”
Because the Chinese study covered patients for two years post-COVID diagnosis, they discovered that many abnormalities gradually decreased. The first scans, at six months, revealed that 54% displayed abnormalities. The good news is that at the two-year mark, only 39% showed evidence of fibrotic interstitial lung disease — 23% were fibrotic, 22% had suffered respiratory symptoms and decreased lung function — including exertional dyspnea. 61% of patients showed complete radiological resolution.
Co-author Qing Ye, MD of the Chinese study, confirmed that it is essential to identify and follow this subset of COVID patients, “In particular, the proportion of fibrotic interstitial lung abnormalities, an important precursor to idiopathic pulmonary fibrosis, remained stable throughout follow-up. Therefore, the fibrotic abnormalities observed in our study might represent a stable, irreversible pulmonary condition, such as lung fibrosis, after COVID-19.”
The UK study team postulates that up to 11% of COVID patients who recover may suffer from lung scarring that can worsen over time. Their study suggests significant implications for some patients released from the hospital after COVID — “substantial” numbers of patients may have fibrotic abnormalities that need to be identified and addressed.
The UK authors revealed that they would re-evaluate their study group at the 12-month mark. They plan to utilize linked electronic health records of hospital admissions and mortality data to support their analyses.
Given the COVID rates in the US, radiologists may need a more detailed COVID patient case history to evaluate abnormalities found during CT chest scans.