The outcome of 12-week corticosteroid therapy in COVID-19-related diffuse interstitial lung abnormalities.

Introduction: The efficacy of long-course corticosteroid therapy in treating COVID-19-related diffuse interstitial lung abnormalities (DILA) needs to be better understood. We aimed to investigate the benefits of 12-week corticosteroid treatment in COVID-19-related DILA by evaluating computed tomography (CT) lung severity scores.

Materials and methods: This retrospective, single-centre observational study included patients aged 18 years or older admitted with moderate to severe COVID-19 pneumonia who received 12 weeks of oral prednisolone between January 2021 and December 2021. We recorded clinical parameters, baseline CT scores and post-treatment, modified Medical Research Council (mMRC) dyspnoea scale and pulmonary function tests.

Results: A total of 330 patients were analysed. The mean (standard deviation, SD) age was 54.6 (14.2) years, and 43% were females. Three-point nine per cent (3.9%) require noninvasive ventilation (NIV), while 14.6% require mechanical ventilation (MV). On follow-up at 12 weeks, the CT patterns showed improvement in ground-glass opacities, perilobular density and consolidation. There was an improvement in the mean (SD) CT score before and after prednisolone therapy, with values of 17.3 (5.3) and 8.6 (5.5), respectively (p<0.001). The median mMRC was 1 (IQR 0-1), and 98.8% had a radiological response. The common side effects of prednisolone therapy were weight gain (13.9%), hyperglycaemia (1.8%) and cushingoid habitus (0.6%).

Conclusion: A 12-week treatment with prednisolone showed significant improvement in CT scores with minimal residual dyspnoea and was relatively safe. Longer duration of steroids may be beneficial in moderate to severe COVID-19- related DILA.