Clinical course and risk factors for severe COVID-19 among Italian patients with cystic fibrosis: a study within the Italian Cystic Fibrosis Society

Abstract

Purpose: To describe the clinical course of COVID-19 in patients with cystic fibrosis (CF) and to identify risk factors for severe COVID-19.

Methods: We conducted a prospective study within the Italian CF Society. CF centers collected baseline and follow-up data of patients with virologically confirmed SARS-CoV-2 infection between March 2020 and June 2021. Odds ratios (ORs) for severe SARS-CoV-2 (as defined by hospital admission) were estimated by logistic regression models.

Results: The study included 236 patients with positive molecular test for SARS-CoV-2. Six patients died, 43 patients were admitted to hospital, 4 admitted to intensive care unit. Pancreatic insufficiency was associated with increased risk of severe COVID-19 (OR 4.04, 95% CI 1.52; 10.8). After adjusting for age and pancreatic insufficiency, forced expiratory volume in one second (FEVp) < 40% (OR 4.54, 95% CI 1.56; 13.2), oxygen therapy (OR 12.3, 95% CI 2.91-51.7), underweight (OR 2.92, 95% CI 1.12; 7.57), organ transplantation (OR 7.31, 95% CI 2.59; 20.7), diabetes (OR 2.67, 95% CI 1.23; 5.80) and liver disease (OR 3.67, 95% CI 1.77; 7.59) were associated with increased risk of severe COVID-19, while use of dornase alfa was associated with a reduced risk (OR 0.34, 95% CI 0.13-0.88). No significant changes were observed in FEVp from baseline to a median follow-up of 2 months (median difference: 0, interquartile range: - 4; 5, P = 0.62).

Conclusion: Clinical features indicative of severe form of CF are associated with increased risk of COVID-19 hospitalization. SARS-CoV-2 infected patients do not experience a deterioration of respiratory function.

Keywords: COVID-19; Cystic fibrosis; Pandemic; SARS-CoV-2.

Fig. 1

Number of patients reported by the Italian cystic fibrosis centers between March 2020 and June 2021 with documented SARS-CoV-2 infection. The x-axis indicates the month of the positive test for SARS-CoV-2

Fig. 2

Odds ratios (ORs) and corresponding 95% confidence intervals for severe COVID-19 in patients with cystic fibrosis infected by SARS-CoV-2 between March 2020 and June 2021 in Italy, according to selected demographic and clinical characteristics. HE highly effective CFTR modulators; OM moderately effective. *P values were obtained using the likelihood ratio test between two nested models (i.e., the null model and the model including the variable of interest)

Fig. 3

Changes in forced expiratory volume in one second (expressed as percentage of predicted) from baseline to follow-up visit (first visit after the end of symptoms or after testing positive for SARS-CoV-2 for asymptomatic patients) in patients with cystic fibrosis infected by SARS-CoV-2 between March 2020 and June 2021 in Italy, according to baseline characteristics and clinical course of the disease. Symbols indicate the median value, bars show the 25th and the 75th percentile. The Wilcoxon sum-rank test was used to compare FEVp changes between groups. Pa Pseudomonas aeruginosa.