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Published on: February 2, 2024
One-year evolution of DLCO changes and respiratory symptoms in patients with post COVID-19 respiratory syndrome
Alberto Fortini1, Aurelio Rosso2, Paolo Cecchini3
1Internal Medicine, San Giovanni di Dio Hospital, Via di Torregalli 3, 50143, Florence, Italy. xfortini@gmail.com.
Purpose:
During a follow-up program of patients admitted for COVID-19 at our non-ICU Unit, we found that 37% of them had decreased diffusing lung capacity for carbon monoxide (DLCO) 3-6 months after discharge. This prospective observational study aimed to evaluate the evolution of changes in DLCO and respiratory symptoms at the 1-year follow-up visit.
Methods:
Seventeen (mean age 71 years; 8 males) of 19 eligible patients (DLCO < 80% of predicted at the 3-6 months follow-up visit) completed the 1-year follow-up visit. One patient refused to participate and 1 patient had died 3 months earlier from myocardial infarction. The visit included a self-reported structured questionnaire, physical exam, blood tests, ECG, and spirometry with DLCO.
Results:
Mean DLCO was significantly improved at the 1-year visit (from 64% of predicted at 3-6 months to 74% of predicted at 1 year; P = 0.003). A clinically significant increase in DLCO (10% or greater) was observed in 11 patients (65%) with complete normalization (> 80% of predicted) in 6 (35%); in the other 6 (35%) it remained unchanged. The prevalence of exertional dyspnea (65-35%, P = 0.17), cough (24-18%, P = 1), and fatigue (76-35%, P = 0.04) decreased at the 1-year visit.
Conclusion:
These results suggest that DLCO and respiratory symptoms tend to normalize or improve 1 year after hospitalization for COVID-19 in most patients. However, there is also a non-negligible number of patients (about one-third) in whom respiratory changes persist and will need prolonged follow-up.
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