RESUMO
Long COVID is a recently described entity that is responsible for significant morbidity and that has consequences ranging from mild to life-threatening. The underlying mechanisms are not completely understood, and treatment options are currently limited, as existing data focus more on risk factors and predictors. Smoking has been reported as a risk factor for poor outcomes of acute SARS-CoV-2 infection and seems to also play a role in mediating post-COVID-19 symptoms. We aimed to review relevant work addressing the interaction between smoking and long COVID in order to characterize smoking's role as a risk factor and possibly identify new research directions. Methods: The PubMed/MEDLINE database was searched using the keywords 'smoking', 'long COVID', and 'post-acute COVID' to identify relevant English-language articles published up to October 2023. Results and conclusions: From the 374 initial hits, a total of 36 papers were deemed relevant to the aim of the review. There was significant variability concerning the ways in which tobacco usage was quantified and reported; still, there is compelling evidence linking smoking to an increased risk of developing manifestations of post-acute-COVID disease. Some clinical conditions, such as dyspnea, cardiovascular symptoms, and cognitive or mental-health impairment, seem to be relatively strongly associated with smoking, while the connection between smoking and upper-airway involvement seems less certain. The available data support recommending smoking cessation as a clinical tool for the prevention of long COVID.
RESUMO
The laboratory tests and identification of risk factors such as comorbidities are essential in the management, treatment and prognosis of patients with chronic respiratory diseases. Performing rigorous monitoring among patients with post-COVID-19 syndrome and early identification of risk factors associated with poor prognosis are crucial in improving patient outcomes. In the present study, 182 patients diagnosed with COVID-19 and PCI during 2020-2022 were included. A clinical and epidemiological evaluation was performed for each patient. Laboratory tests at admission included complete blood count, Erythrocyte Sedimentation Rate (ESR) and biochemical tests. Receiver operating curve (ROC) and area under the curve (AUC) were calculated to compare the diagnostic performance of each parameter. Regarding comorbidities, arterial hypertension, diabetes mellitus and obesity were the most frequent ones. In the case of chronic lung diseases, asthma and Chronic Obstructive Pulmonary Disease (COPD) were the most frequent. Pleurisy was found especially in patients with PCI Variations in serum LDH values were observed, especially in severe forms of COVID-19 in 2020, with a mean value of 481.44 U/L, compared to patients with PCI, whose mean values (122 U/L) were within the biological range of reference. High neutrophil/lymphocyte ratio (NLR) values quantified in this study were especially associated with moderate and severe forms of COVID-19 and also PCI. The Spearman correlation coefficient was determined to measure the correlations between the clinical parameters of all investigated subjects. A value of p < 0.05 was considered statistically significant. The statistical results indicated that serum lactate dehydrogenase (LDH), glucose and C-reactive protein (CRP) are sensitive markers with a diagnostic role in COVID-19, and lymphocyte (Ly) count, CRP, ESR and glucose were evidenced to be target markers in PCI. LDH values were observed to be statistically significant (p < 0.005) in patients with COVID-19 and obesity evaluated in 2021, while Ly count was statistically significant (p = 0.05) in patients with PCI and arterial hypertension. Regarding comorbidities, it has been observed that obesity, arterial hypertension and cardiovascular diseases represent risk factors in COVID-19/PCI, associated especially with the severe forms of the disease.