Estudio multidimensional de la condición post COVID-19

Resum

INTRODUCTION Coronavirus disease 2019 (COVID-19) is still far from over. The term "post-COVID condition" (PCC) has now been adopted to refer to new, recurrent or continuous symptomatology, to sequelae secondary to organ damage and to the effects of hospitalization that appear after the acute process caused by the coronavirus type 2 causing Severe Acute Respiratory Syndrome (SARS-CoV-2). The overall objective is to investigate in a multidimensional way on PPC, which we will do by investigating: persistent symptomatology, residual organ damage, the role of PET CT in the follow-up and the relationships between the different variables that may predispose to the development of PCC. This doctoral thesis is the result of 3 research works on PPC carried out by the PhD student, all of them published in journals indexed in the Journal Citation Report (JCR). MATERIAL AND METHODS The articles that make up this thesis are prospective studies of post COVID patients who were referred to the Pneumology Department of the Hospital Universitario Virgen de las Nieves (HUVN) in Granada, Spain. Article 1: Prospective cohort study of patients hospitalized (or not) for COVID-19 who completed a 6-month follow-up of evolution. Article 2: Pilot study on a naturalistic cohort of a series of cases followed up 3 months after COVID-19. Article 3: Prospective cohort study of patients hospitalized for COVID-19 who completed a follow-up of 1 year of evolution. RESULTS Article 1: 217 patients completed follow-up and 154 patients (73.3%) still had residual clinical symptoms 6 months after COVID-19. We found significant association (p<0.05) between patient gender with the following variables: fatigue, arthralgias, fever, dyspnea, emotional disturbances, depression, cognitive decline, hemoglobin, total bilirubin and ferritin. Previous respiratory disease (PRD) and hospitalization status are strongly associated with specific demographic characteristics, clinical symptoms, mental health, and respiratory function tests (PFT) based on single and multiple features of PCC. Article 2: At 2-3 months after discharge, 11 patients (55%) were positive, with hypermetabolic mediastinal lymphadenopathy in 90.9%. They were elderly patients with an elevated Charlson index; on admission they presented with fatigue and dyspnea along with with lower hemoglobin and lymphocyte counts. Peak standardized uptake value (peak SUV) of the target lesion and pulmonary total tumor glycolysis (TLG) were significantly correlated with acute phase reactants and white blood cell counts on admission, during hospital stay and 2-3 months after discharge. Article 3: Of the 157 patients who completed the study, 49 (31.2%) met criteria for abnormal PFT at 12 months. Multivariate analysis of patients with such functional deterioration showed a significant association(p<0,05) with the following variables: elevated Charlson index and, variables upon admission of chest X-ray with the presence of pneumonia of central and/or mixed distribution, anemia, intensive care unit (ICU) stay and need for corticosteroid treatment. Likewise, we found a significant association between such pulmonary impairment and abnormal alpha 1 antitrypsin (AAT) values along with Pi*MZ deficient allelic genotyping. CONCLUSIONS: Article 1: After 6 months of acute SARS-CoV-2 infection, the presence of post-COVID- 19 condition is verified among our patients. Its development is independent of the severity of the disease during the acute phase and, having or not previous respiratory comorbidities. However, it is influenced by gender. Specifically, female sex is a favorable factor for the persistence of the symptomatology. Article 2: Respiratory function testing (PFT) in conjunction with [18F] FDG PET-CT is more sensitive than CT alone in identifying candidates with pulmonary sequelae after COVID- 19. Article 3: The presence of low AAT levels and/or Pi*MZ deficient allelic genotyping, high Charlson index, the presence on admission of; chest x-ray with pneumonia, anemia, ICU stay and, need for methylprednisolone boluses contribute to such worsening of pulmonary function in the long term.