Objective and Purpose of Study
1. The main objective is to determine risks factors and prognosis of patients with COVID-19 infection who have been admitted to Spanish ICUs between the beginning and end of the pandemic in Spain. Special attention will be placed on identifying differential expression of prognostic factors based on sex.
2. The second objective is to perform a follow-up of patients within 6 months after discharge from ICU and hospital in order to determine mortality (including at 1-year mark), functional respiratory and cardiovascular consequences, and quality of life.
3. The third objective is to perform an epigenetic study in cases, in which a blood sample can be drawn. The aim of such undertaking is to define molecular signatures in liquid biopsies that can provide information regarding prognosis, and treatment monitoring and response to therapy.
4. Lastly, predictive ability of response to therapy and mortality will be assessed from a panel of protein biomarkers that participate in key physiological pathways of the disease's pathogenesis. This could, in turn, help select prospective treatments with greater potential of being successful in each patient.
Principal and Secondary Variables
1. Prior epidemiological data of the patient
2. Biological and clinical data, including treatment administered upon hospital admission
3. Biological and clinical data, including treatments administered upon and during ICU admission until either discharge from ICU or hospital, or death
4. Specific data regarding artificial ventilation and ECMO since the beginning, as well as sequentially, from intubation to either extubation or death
5. Biological and clinical data upon hospital discharge
6. Clinical follow-up of patients who survive within 6 months, including: functional respiratory tests, echocardiograms and surveys regarding quality of life
7. Intrahospital and intra-ICU mortality will be registered at 28- and 90-day marks, as well as within 6 months and 1 year
8. 1000 blood samples will be drawn for the epigenetic study The molecular profile of a non-coding RNA (ncRNA), specifically the microRNA (miRNA) pattern in liquid biopsy, will be analyzed. A circulating miRNA signature is closer to the phenotype than genomic markers and can provide information regarding epigenetic regulation, cell activation, tissue repair, and metabolic processes in addition to that afforded by clinical predictors and classic risk factors. miRNAs offer appropriate biochemical properties that are highly stable; have a long half-life in biological samples used in clinical laboratories (serum/plasma); can be efficiently and relatively rapidly quantified with high sensitivity and specificity by RT-qPCR; and can serve as a profitable tool for the assessment of risks and disease control.
All of these characteristics have led distinct authors to propose the clinical application of miRNA in either the short or medium term.
The experimental design comprises two phases. In the first approximation, a screening of non-coding RNA (ncRNA) will be performed in a sub-population of patients (n=200). The number of samples surpasses the quantity recommended for this type of studies. (Schurch y cols., RNA, 2016). A quotation will be requested for the screening of ncRNA by HTG EdgeSeq miRNA Whole Transcriptome Assay system (HTG). Using next generation sequencing (NGS), this method allows for the quantification of 2083 human candidates. All of the procedure steps will be completed in suitable physical locations in accordance with code OP No. 0028. All of the samples will be prepared in accordance with code No. 0036.
Screening results will be validated in the validation cohort (n=800) with RT-qPCR, a gold-standard technique. The budget includes material necessary for RNA extraction (miRNeasy Serum/Plasma isolation kits, Qiagen; spike-in; carrier RNA; consumables) and expression quantification of ncRNA in biofluids (RT-qPCR miRCURY LNA Universal RT microRNA PCR System kits, Qiagen; endogenous controls; consumables. Studies will be carried out at the TRRM Group facilities in the IRBLleida. The laboratory has the necessary team and material to isolate and quantify RNA, and store reagents and samples (cold stores, freezers of 20ºC and -80ºC).
9.- For the study of prognostic biomarkers, concentration of biomarkers in plasma that are key to potentially useful drugs' mechanism of action in this disease will be assessed. This quantification could provide guidance on drug usage (lymphocyte count will be obtained from a blood count):
