Long COVID and Lung Involvement: A One-Year Longitudinal, Real-Life Study

<i>Background and Objectives</i>: Long COVID as a condition typically manifests itself three months after the initial onset of SARS-CoV-2 infection, with symptoms persisting for a minimum of two months. The aim of the present research was to identify potential predictors of post-COVID-19 syndrome (long COVID-19) and to evaluate factors associated with the presence of post-COVID-19 interstitial lung disease and functional decline. <i>Materials and Methods:</i> 210 patients hospitalized for confirmed SARS-CoV-2 infections mild, moderate, severe, and critical form have been evaluated at 3, 6 and twelve months. <i>Results:</i> Among them only one has been with a suspicion of interstitial lung disease after one year, the rest had no change in the lung. No risk factor from the baseline/3-month or 6-month evaluations significantly influenced patients' status at 12 months. The longer the duration of hospitalization, the lower the FVC and DLCO were at 3 months, but the longer the duration of hospitalization, the higher the number of symptoms at 3 months and 6 months. In a multivariate linear regression analysis, the number of hospitalization days remained statistically significant only for the number of symptoms at 3 months and 6 months. <i>Conclusions</i>: Long COVID seems to be related to the severity of the initial disease, and among the most persistent. Post-COVID-19 interstitial lung disease does not seem to be a frequent entity, as in our study only 0.5% out of 210 patients had it.