The role of smoking in COVID-19 progression: a comprehensive meta-analysis

Bronchoalveolar lavage single-cell transcriptomics reveals immune dysregulations driving COVID-19 severity

The continuous threats posed by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, including the emergence of potentially more infectious and deadly variants, necessitate ongoing studies to uncover novel and detailed mechanisms driving disease severity. Using single-cell transcriptomics, we conducted a secondary data analysis of bronchoalveolar lavage fluid (BALF) from COVID-19 patients of varying severities and healthy controls to comprehensively examine immune responses. We observed significant immune cell alterations correlating with disease severity. In severe cases, macrophages showed upregulation of pro-inflammatory genes TNFα and IL1β, contributing to severe inflammation and tissue damage. Neutrophils exhibited increased activation, marked by S100A8, CXCL8, and IL1β expression, with extended viability and reduced phagocytosis. Genes such as MCL1 and HIF1α supported extended viability, while MSR1 and MRC1 indicated reduced phagocytosis. Enhanced formation of neutrophil extracellular traps (NETs) and reduced clearance, indicated by NET-associated markers, were linked to thrombo-inflammation and organ damage. Both macrophages and neutrophils in severe cases showed impaired efferocytosis, indicated by decreased expression of MSR1 and TREM2 in macrophages and downregulation of FCGR3B in neutrophils, leading to the accumulation of apoptotic cells and exacerbating inflammation. Severe cases were characterized by M1 macrophages with high TNFα and IL1β, while milder cases had M2 macrophages with elevated PPARγ. Dendritic cells (DCs) in severe cases exhibited reduced proportions and attenuated expression of MHC class I genes (HLA-A, HLA-B, HLA-C) and co-stimulatory molecules (CD80, CD86), alongside increased cytochrome c expression, indicating impaired antigen presentation and enhanced apoptosis. NK and T cells in severe cases demonstrated altered receptor and gene expression, with increased activation markers IFNγ and ISG15, suggesting a paradoxical state of activation and exhaustion. This analysis highlights the critical role of dysregulated neutrophil, macrophage, dendritic cell, NK, and T cell responses in severe COVID-19, identifying potential therapeutic targets and providing novel insights into the disease.

Estimating the association between cigarette and e-cigarette use patterns and SARS-CoV-2 negative conversion time: retrospective online survey in China

BACKGROUND

Cigarette smoking has been reported to be associated with SARS-CoV-2 negative conversion, while little is known about the effect of its dual use with e-cigarettes. This study aimed to investigate whether tobacco product use patterns including e-cigarette use were linked with delayed negative conversion of SARS-CoV-2.

METHODS

An online national survey was conducted from January 28 through February 21, 2023, targeting a community-based population in mainland of China after peak waves of the coronavirus disease 2019 (COVID-19). Participants were followed from the onset of COVID-19 symptoms until the negative conversion day or the day of answering the questionnaire as the endpoint of the study. Multi-variable adjusted Cox proportional hazard models were used to compare the negative conversion time of SARS-CoV-2 across different cigarette and e-cigarette use patterns.

RESULTS

A total of 66,537 participants infected with COVID-19 were enrolled and 13,294 were included in the analyses. During the median duration of 7 days (interquartile range 5 to 10 days), a total of 11,587 (87.2%) had a negative conversion. Compared with never users, current exclusive smokers (multi-variable adjusted HR 0.59, 95% CI 0.48-0.71), current dual users (HR 0.31, 95% CI 0.22-0.44), and previous smokers (HR 0.56, 95% CI 0.37-0.83) took longer to turn negative after 10 days of follow-up.

CONCLUSIONS

Both current exclusive cigarette use and dual use of cigarettes and e-cigarettes were associated with the delayed negative conversion of SARS-CoV-2, which strengthens the importance of smoking and vaping cessation messaging and community-based tobacco control strategies during pandemics like COVID-19 next time.

ACE and ACE2 activities and polymorphisms assessment: A populational study from Ipaussu (SP, Brazil) during the COVID-19 pandemic

AIM

The angiotensin-converting enzyme 2 (ACE2) and its homolog, the angiotensin converting enzyme 1 (ACE), are involved in COVID-19 physiopathology. Alterations in the enzymatic structure, expression, and/or activity may influence the risk of infection and severity of disease. For this reason, we aimed to identify different allelic forms of ACE2 G8790A and ACE I/D polymorphisms in a Brazilian cohort and evaluate their impact on ACE and ACE2 activities and their association with COVID-19 susceptibility and severity.

MAIN METHODS

A total of 549 COVID-19-negative and 270 COVID-19-positive participants from Ipaussu, Sao Paulo, Brazil, were recruited. ACE2 and ACE activities were measured by fluorogenic assays using MCA-Ala-Pro-Lys(Dnp) as the substrate for ACE2 and Z-Phe-His-Leu-OH (Z-FHL) and Hippuryl-His-Leu-OH (h-HL) as substrates for ACE. Genomic DNA was extracted from EDTA-peripheral blood, and the regions of the genes containing ACE2 G8790A and ACE I/D polymorphisms were amplified by PCR-restriction fragment length polymorphism and real-time PCR, respectively.

KEY FINDINGS

The G allele of ACE2 G8790A polymorphism and D allele of ACE I/D polymorphism are associated with increased ACE and ACE2 activities. ACE activity ratio (Z-FHL/h-HL), an inflammatory marker, is increased in women with GG genotype and COVID-19-positive diagnosis.

SIGNIFICANCE

For the first time, it was demonstrated that in females, the GG genotype is associated with increased ACE activity ratio (Z-FHL/h-HL) in the COVID-19-positive group. Elevated ACE activity ratio (Z-FHL/h-HL) is highly linked to inflammation and may justify the associations between the G genotype and COVID-19 severity of symptoms and outcomes.

The effect of pre-hospital use of RAS inhibitors on COVID-19 mortality

The effect of pre-hospital use of renin-angiotensin system (RAS) inhibitors (angiotensin-converting enzyme inhibitors (ACEis)/angiotensin receptor blockers (ARBs)) on clinical outcomes of hypertensive patients with COVID-19 has been questioned due to conflicting reports on this issue. After applying exclusion criteria, 175 COVID-19 hospitalized patients admitted to the Tishreen Hospital from January 1 to July 31, 2021 were retrospectively enrolled in this study. Baseline characteristics and in-hospital mortality rate were assessed between hypertensive (N = 91, 52%) and non-hypertensive (N = 84, 48%) patients, as well as between patients taking ACEis/ARBs and non-ACEis/ARBs within the hypertensive group. A lower mortality rate (51.2 versus 31.9%, p = 0.009) was observed in the hypertensive group (mean age 64.6 years, 64.8% males) compared to the non-hypertensive (mean age 62.6 years, 66.7% males). Patients' mortality in the non-hypertensive group was associated with lower blood oxygen saturation (SPO2 = 75 versus 86%, p = 0.002), increased levels of inflammatory (CRP, white blood cell and neutrophils count), and tissue/renal injury markers (LDH, urea, and creatinine). In the hypertensive group, a lower mortality rate was noted in the ACEis/ARBs group compared to the non-ACEis/ARBs (24.1 versus 45.5%, p = 0.036), and this was associated with a decrease in D-DIMER levels, although not significant (1723 versus 2683 ng/mL, p > 0.05). Death in the non-ACEis/ARBs group was associated with decreased SPO2 and tissue/renal injury markers (LDH, CK, AST, urea, and creatinine). We concluded that hypertension is not a direct cause of poor prognosis in COVID-19 patients and that multi-organ damage is a significant indicator of death from COVID-19. RAS inhibitors could improve the survival of hypertensive COVID-19 patients.

Spectrum of COVID-19 cases in Arkhangelsk, Northwest Russia: Findings from a population-based study linking serosurvey, registry data, and self-reports of symptoms

INTRODUCTION

The spectrum of COVID-19 manifestations makes it challenging to estimate the exact proportion of people who had the infection in a population, with the proportion of asymptomatic cases likely being underestimated. We aimed to assess and describe the spectrum of COVID-19 cases in a sample of adult population aged 40-74 years in Arkhangelsk, Northwest Russia, a year after the start of the pandemic.

MATERIALS AND METHODS

A population-based survey conducted between February 24, 2021 and June 30, 2021 with an unvaccinated sample aged 40-74 years (N = 1089) combined a serological survey data, national COVID-19 case registry, and self-reported data on COVID-19 experience and symptoms. Based on the agreement between these sources, we classified the study participants as non-infected and previously infected (asymptomatic, non-hospitalized and hospitalized symptomatic) cases, and compared these groups regarding demographics, lifestyle and health characteristics.

RESULTS

After a year of the pandemic in Arkhangelsk, 59.7% 95% confidence intervals (CI) (56.7; 62.6) of the surveyed population had had COVID-19. Among those who had been infected, symptomatic cases comprised 47.1% 95% CI (43.2; 51.0), with 8.6% 95% CI (6.6; 11.1) of them having been hospitalized. Of the asymptomatic cases, 96.2% were not captured by the healthcare system. Older age was positively associated, while smoking showed a negative association with symptomatic COVID-19. Individuals older than 65 years, and those with poor self-rated health were more likely to be hospitalized.

CONCLUSION

More than half of the infected individuals were not captured by the healthcare-based registry, mainly those with asymptomatic infections. COVID-19 severity was positively associated with older age and poor self-rated health, and inversely associated with smoking. Combining different sources of surveillance data could reduce the number of unidentified asymptomatic cases and enhance surveillance for emerging infections.

Associations between clinical data, vaccination status, antibody responses, and post-COVID-19 symptoms in Thais infected with SARS-CoV-2 Delta and Omicron variants: a 1-year follow-up study

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), led to a global pandemic from 2020. In Thailand, five waves of outbreaks were recorded, with the fourth and fifth waves driven by the Delta and Omicron variants, resulting in over 20,000 new confirmed cases daily at their peaks.

METHODS

This cross-sectional study investigated the associations between clinical symptoms, vaccination status, antibody responses, and post-COVID-19 sequelae in COVID-19 patients. Plasma samples and clinical data were collected from participants admitted to hospitals in Thailand between July 2021 and August 2022, with follow-ups conducted for one year. The study included 110 participants infected with either the Delta (n = 46) or Omicron (n = 64) variants. Virus genotypes were confirmed by RT-PCR of nasal swab RNA and partial nucleotide sequencing of the S gene. IgG and IgA antibody levels against the receptor-binding domain (RBD) of SARS-CoV-2 Delta and Omicron variants were measured in plasma samples using ELISA.

RESULTS

Pneumonia was found to be associated with Delta variant infections, while sore throat, congestion or runny nose, and headache were linked to Omicron infections. Vaccination with fewer than two doses and diabetes mellitus were significantly associated with higher disease severity. Specific IgG and IgA antibodies against the RBD of the Delta variant generally rose by day 14 and were maintained for up to two months, whereas the pattern of antibody response to the Omicron variant was less clear. Antibody risings were found to be positively associated with pneumonia, certain underlying conditions (obesity, hypertension, dyslipidemia, and diabetes mellitus), and age ≥ 60 years. Delta variant infections were associated with forgetfulness, hair loss, and headache during the 1-year post-infection period. Females were more likely to experience hair loss, forgetfulness, and joint pain, while older age was associated with joint pain.

CONCLUSIONS

This study enhances our understanding of SARS-CoV-2 infections in Thais, particularly concerning the Delta and Omicron variants. The findings can inform public health planning and response strategies for future outbreaks of SARS-CoV-2 or other emerging viral diseases.

The impact of smoking on COVID-19-related mortality: a Brazilian national cohort study

INTRODUCTION

Current evidence suggests the potential heightened vulnerability of smokers to severe coronavirus disease (COVID-19) outcomes.

AIMS

This study aimed to analyze the clinical outcomes and mortality related to tobacco use in a cohort of hospitalized Brazilian COVID-19 patients.

METHODS

This retrospective cohort study analyzed adults hospitalized for COVID-19 in Brazil using the SIVEP-Gripe database (official data reported by public and private healthcare facilities for monitoring severe acute respiratory syndrome cases in Brazil). The inclusion criteria were patients over 18 years of age with a positive RT-qPCR test for SARS-CoV-2. The analysis focused on in-hospital mortality, considering smoking as an exposure variable, and included covariates such as age, gender, and comorbidities. Smoking history was collected from the self-reported field in the database. Statistical analyses included descriptive statistics, crude Odds Ratios, and multivariable binary logistic regression.

RESULTS

This study included 2,124,285 COVID-19 patients, among whom 44,774 (2.1 %) were smokers. The average age of the smokers was higher than that of the never-smokers (65.3 years vs. 59.7 years). The clinical outcomes revealed that smokers had higher rates of intensive care unit admission (51.6 % vs. 37.2 % for never-smokers), invasive ventilatory support (31.5 % vs. 20.2 % for never-smokers), and higher mortality (42.7 % vs. 31.8 % for never smokers). In the multivariable analysis, smokers demonstrated a heightened risk of death (aOR 1.23; 95 % CI 1.19-1.25).

CONCLUSIONS

This large populational-based cohort study confirms the current evidence and underscore the critical importance of recognizing smoking as a substantial risk factor for adverse outcomes in COVID-19 patients.

Exploring the Relationship Between Cannabis Use And COVID-19 Outcomes

Background: Cannabis use is becoming increasingly prevalent worldwide, yet the full spectrum of its effects largely remain unknown. Although cannabis have immunomodulatory properties, there remains a significant gap in our understanding of the potential impact of marijuana use on COVID-19 outcomes. The purpose of this study is to evaluate the effect of chronic cannabis use on severe COVID-19. Materials and Methods: National Inpatient Sample Database was used to sample individuals admitted with the diagnosis of COVID-19. Patients were divided into two groups based on cannabis use. Baseline demographics and comorbidities were collected using ICD-10 codes. Patients with missing data or age under 18 were excluded. Propensity matching using R was performed to match cannabis users to non-cannabis users 1:1 on age, race, gender, and 17 other comorbidities. The primary outcome was severe COVID-19 infection, defined as a composite of acute respiratory failure, intubation, acute respiratory distress syndrome (ARDS), or severe sepsis with multiorgan failure. Results: Out of 322,214 patients included in the study, 2,603 were cannabis users. Cannabis users were younger and had higher prevalence of tobacco use. On initial analysis, cannabis users had significantly lower rates of severe COVID-19 infection, intubation, ARDS, acute respiratory failure, severe sepsis with multiorgan failure, mortality, and shorter length of hospital stay. After 1:1 matching, cannabis use was associated with lower rates of severe COVID-19 infection, intubation, ARDS, acute respiratory failure, severe sepsis with multiorgan failure, mortality, and shorter length of hospital stay. Conclusion: Cannabis users had better outcomes and mortality compared with non-users. The beneficial effect of cannabis use may be attributed to its immunomodulatory effects.

Prevalence and association between alcohol, tobacco, and COVID-19: a study from a tribal predominant district in eastern India

Introduction

Alcohol and tobacco use has been proposed to significantly affect COVID-19 outcomes. The study aimed to estimate the prevalence of alcohol and tobacco use among COVID-19-positive patients and compare it with the general population prevalence rates. It also aimed to assess and determine the association between the severity of COVID-19 illness and the complications with alcohol and tobacco use.

Method

For this, a cross-sectional, retrospective, telephone-based study was conducted using a structured questionnaire among COVID-19 diagnosed patients in the district of Deoghar of the Indian state of Jharkhand. A multinomial logistic regression is done to determine the association.

Results

Among 1,425 patients interviewed, tobacco and alcohol were used by 22.31 and 9.96%, significantly more than the prevalence of tobacco (Z = 4.9485, p < 0.00001) and alcohol use (Z = 7.118, p < 0.00001), respectively, in the district (tobacco-11.7% and alcohol-4.8%).In a regression model, patients with co-morbidity had higher odds of severe [3.34 (1.99-5.62)] and moderate [2.95 (1.97-4.41)] COVID-19. Young [0.12 (0.04-0.38)] and middle-aged individuals [0.23 (0.13-0.4)], people below the poverty line 0.28 (0.11-0.69) are at lower odds of severe COVID-19. Tobacco users [1.58 (1.16-2.14)], alcohol users [1.53 (1.03-2.28)], incomplete vaccination [3.24 (1.49-7.01)], and patients with comorbidity [3.6 (2.79-4.68)] were found to have higher odds of post-COVID-19 complications.

Discussion

People with COVID-19 in our study population had significantly higher tobacco and alcohol use compared to the general population. Tobacco and alcohol use significantly increases the risk of post-COVID-19 complications. The study highlights the need for addiction treatment services to prevent complications during future pandemics.

Smoking and vaping alter genes related to mechanisms of SARS-CoV-2 susceptibility and severity: a systematic review and meta-analysis

BACKGROUND

Evidence for the impact of smoking on coronavirus disease 2019 (COVID-19) is contradictory, and there is little research on vaping. Here we provide greater clarity on mechanisms perturbed by tobacco cigarette, electronic cigarette and nicotine exposures that may impact the risks of infection and/or disease severity.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the Ovid and Web of Science databases were searched. Study design and exposure-induced gene expression changes were extracted. Each study was quality assessed and higher confidence scores were assigned to genes consistently changed across multiple studies following the same exposure. These genes were used to explore pathways significantly altered following exposure.

RESULTS

125 studies provided data on 480 genes altered by exposure to tobacco cigarettes, e-cigarettes, nicotine or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Genes involved in both SARS-CoV-2 viral-entry and inflammation were changed following exposure. Pathway analysis revealed that many of those genes with high confidence scores are involved in common cellular processes relating to hyperinflammatory immune responses.

CONCLUSION

Exposure to tobacco cigarettes, e-cigarettes or nicotine may therefore impact initial host-pathogen interactions and disease severity. Smokers and vapers of e-cigarettes with nicotine could potentially be at increased risk of SARS-CoV-2 infection, associated cytokine storm, and acute respiratory distress syndrome. However, further research is required, particularly on e-cigarettes, to determine the biological mechanisms involved in perturbation of viral-entry genes and host-pathogen interactions and subsequent responses within the respiratory tract. This will improve our physiological understanding of the impact of smoking and vaping on COVID-19, informing public health advice and providing improved guidance for management of SARS-CoV-2 and other respiratory viruses.

Smoking-Induced DNA Hydroxymethylation Signature Is Less Pronounced than True DNA Methylation: The Population-Based KORA Fit Cohort

Despite extensive research on 5-methylcytosine (5mC) in relation to smoking, there has been limited exploration into the interaction between smoking and 5-hydroxymethylcytosine (5hmC). In this study, total DNA methylation (5mC+5hmC), true DNA methylation (5mC) and hydroxymethylation (5hmC) levels were profiled utilizing conventional bisulphite (BS) and oxidative bisulphite (oxBS) treatment, measured with the Illumina Infinium Methylation EPIC BeadChip. An epigenome-wide association study (EWAS) of 5mC+5hmC methylation revealed a total of 38,575 differentially methylated positions (DMPs) and 2023 differentially methylated regions (DMRs) associated with current smoking, along with 82 DMPs and 76 DMRs associated with former smoking (FDR-adjusted p < 0.05). Additionally, a focused examination of 5mC identified 33 DMPs linked to current smoking and 1 DMP associated with former smoking (FDR-adjusted p < 0.05). In the 5hmC category, eight DMPs related to current smoking and two DMPs tied to former smoking were identified, each meeting a suggestive threshold (p < 1 × 10-5). The substantial number of recognized DMPs, including 5mC+5hmC (7069/38,575, 2/82), 5mC (0/33, 1/1), and 5hmC (2/8, 0/2), have not been previously reported. Our findings corroborated previously established methylation positions and revealed novel candidates linked to tobacco smoking. Moreover, the identification of hydroxymethylated CpG sites with suggestive links provides avenues for future research.

Associations between lifestyle factors and COVID-19 infection rates: a cross-sectional analysis in the USA

Introduction

The COVID-19 pandemic has underscored the vital connection between lifestyle factors and health outcomes, highlighting the need to understand how lifestyle choices influence both chronic and infectious diseases. Despite known links between lifestyle factors and chronic diseases, the relationship between these factors and infectious diseases like COVID-19 warrants further investigation.

Methods

This cross-sectional study used an anonymous survey collected from a diverse sample of US residents aged 18 or older. Excluding individuals under 18 or residing outside the USA, the survey captured data on diet, body mass index, smoking status, alcohol consumption, physical activity, sleep duration, COVID-19 infection status, socio-demographics and other potential confounders. Statistical analysis was performed using χ2 tests and logistic regression to explore the associations between lifestyle factors and COVID-19 infection, with a particular focus on gender differences.

Results

Among 1032 participants, the prevalence of COVID-19 was higher in women (42.8%) compared with men (32.0%). Significant associations were found between inadequate sleep (less than 4 hours per day) and increased risk of COVID-19 in both genders (OR=2.89, 95% CI: 1.13 to 7.35, p=0.02 for men; OR=5.69, 95% CI: 3.14 to 10.29, p<0.00 for women). Additionally, a significant association was observed between a lifestyle index, incorporating multiple lifestyle factors and COVID-19 infection in women (OR=1.79, 95% CI: 1.05 to 3.025, p=0.03).

Conclusions

The findings indicate a potential link between lifestyle factors and susceptibility to COVID-19, with inadequate sleep identified as a significant risk factor. These results suggest that promoting a healthy lifestyle could be an effective strategy for controlling the pandemic and mitigating the impact of infectious diseases. Further research is recommended to explore the role of restful sleep in preventing COVID-19 for men and women (including multiple lifestyle factors among women).

Effect of Cigarette Smoking on Clinical and Molecular Endpoints in COPD Patients

Cigarette smoking is a primary contributor to mortality risks and is associated with various diseases. Among these, COPD represents a significant contributor to global mortality and disability. The objective of this study is to investigate the effect of smoking on a selected battery of variables, with an emphasis on DNA damage. A total of 87 elderly patients diagnosed with COPD, divided into three groups based on their smoking history (current, former, never-smokers), were evaluated using a cross-sectional approach. Clinical features including mortality and inflammatory/oxidative parameters (Lymphocytes/Monocytes, Neutrophils/Lymphocytes, Platelets/Lymphocytes ratio), SII, MDA, 8-Oxo-dG, and IL6 (ELISA assay), as well as DNA damage (comet assay), were investigated. Virus infection, i.e., influenza A virus subtype H1N1, JC polyomavirus (JCPyV), BK polyomavirus (BKPyV), and Torquetenovirus (TTV), was also tested. Current smokers exhibit higher levels of comorbidity (CIRS; p < 0.001), Platelets/Lymphocytes ratio (p < 0.001), systemic immune inflammation (p < 0.05), and DNA damage (p < 0.001). Former smokers also showed higher values for parameters associated with oxidative damage and showed a much lower probability of surviving over 5 years compared to never- and current smokers (p < 0.0017). This study showed a clear interaction between events which are relevant to the oxidative pathway and cigarette smoking. A category of particular interest is represented by former smokers, especially for lower survival, possibly due to the presence of more health problems. Our findings raise also the attention to other parameters which are significantly affected by smoking and are useful to monitor COPD patients starting a program of pulmonary rehabilitation (DNA damage, inflammation parameters, and selected viral infections).

Association between COVID-19 severity and tobacco smoking status: a retrospective cohort study using propensity score matching weights analysis

INTRODUCTION

The COVID-19 pandemic continues to be a global threat to public health, with over 766 million confirmed cases and more than 6 million reported deaths. Patients with a smoking history are at a greater risk of severe respiratory complications and death due to COVID-19. This study investigated the association between smoking history and adverse clinical outcomes among COVID-19 patients admitted to a designated medical centre in Saudi Arabia.

METHODS

A retrospective observational cohort study was conducted using patient chart review data from a large tertiary medical centre in the eastern region of the country. Patients admitted between January and December 2020 were screened. The inclusion criteria were ≥18 years of age and confirmed COVID-19 infection via reverse-transcription-PCR. The exclusion criteria were unconfirmed COVID-19 infection, non-COVID-19 admissions, unconfirmed smoking status, vaccinated individuals, essential chart information missing or refusal to consent. Statistical analyses comprised crude estimates, matching weights (as the main analysis) and directed acyclic graphs (DAGs) causal pathway analysis using an ordinal regression model.

RESULTS

The sample comprised 447 patients (never-smoker=321; ever-smoker=126). The median age (IQR) was 50 years (39-58), and 73.4% of the sample were males. A matching weights procedure was employed to ensure covariate balance. The analysis revealed that the odds of developing severe COVID-19 were higher in the ever-smoker group with an OR of 1.44 (95% CI 0.90 to 2.32, p=0.130). This was primarily due to an increase in non-invasive oxygen therapy with an OR of 1.05 (95% CI 0.99 to 1.10, p=0.101). The findings were consistent across the different analytical methods employed, including crude estimates and DAGs causal pathway analysis.

CONCLUSION

Our findings suggest that smoking may increase the risk of adverse COVID-19 outcomes. However, the study was limited by its retrospective design and small sample size. Further research is therefore needed to confirm the findings.

The Association between Lifestyle Factors and COVID-19: Findings from Qatar Biobank

Coronavirus Disease 2019 (COVID-19) manifestations range from mild to severe life-threatening symptoms, including death. COVID-19 susceptibility has been associated with various factors, but studies in Qatar are limited. The objective of this study was to investigate the correlation between COVID-19 susceptibility and various sociodemographic and lifestyle factors, including age, gender, body mass index, smoking status, education level, dietary patterns, supplement usage, physical activity, a history of bariatric surgery, diabetes, and hypertension. We utilized logistic regression to analyze these associations, using the data of 10,000 adult participants, aged from 18 to 79, from Qatar Biobank. In total, 10.5% (n = 1045) of the participants had COVID-19. Compared to non-smokers, current and ex-smokers had lower odds of having COVID-19 (odds ratio [OR] = 0.55; 95% CI: 0.44-0.68 and OR = 0.70; 95% CI: 0.57-0.86, respectively). Vitamin D supplement use was associated with an 18% reduction in the likelihood of contracting COVID-19 (OR = 0.82; 95% CI: 0.69-0.97). Obesity (BMI ≥ 30 kg/m2), a history of bariatric surgery, and higher adherence to the modern dietary pattern-characterized by the consumption of foods high in saturated fat and refined carbohydrates-were positively associated with COVID-19. Our findings indicate that adopting a healthy lifestyle may be helpful in the prevention of COVID-19 infection.

Evaluation of Olfactory Dysfunction Among COVID-19 Patients in Baghdad, Iraq

Background SARS‑CoV‑2 (COVID-19) causes olfactory dysfunction which is characterized by anosmia or hyposmia. Characterization of olfactory dysfunction has added value to the diagnosis and prognosis of the disease. Nevertheless, scarce information exists about COVID-19 patients suffering from olfactory dysfunction in Iraq. This study aimed to identify olfactory dysfunction (anosmia or hyposmia) in Iraqi COVID-19 patients and examine their response to smell exercise at Baghdad Medical City Complex, Baghdad, Iraq. Methodology This case series prospective study involving 300 patients (160 males and 140 females) with COVID-19 infection was conducted from June 1, 2020, to October 1, 2021. We recorded signs and symptoms of COVID-19 among patients by examining olfactory dysfunction, n-butanol olfaction test, and smell test exercise. Results Anosmia and hyposmia were found in 69.3% and 30.7% of the patients, respectively; of these, 65.7% were of sudden onset. The association between olfactory dysfunction and smoking was not significant. The most frequent signs and symptoms of COVID-19 were fatigue, fever, loss of taste, myalgia, headache, sore throat, cough, depressed appetite, dyspnea, nausea, abdominal pain, and diarrhea. The highest frequencies of occurrence of anosmia (30.7%) and hyposmia (13.3%) were in the age group of 31-40 years. The majority (47.7%) of patients with olfactory dysfunction recovered within one month of COVID-19 onset. The rest of the patients recovered within one month to 16 months. The most commonly encountered ear, nose, and throat symptoms were nasal obstruction, rhinorrhea, and facial/ear pain. The percentages of patients with anosmia and hyposmia recovering with smell exercise were significant at 64.7% and 25.3%, respectively. Conclusions The prognosis of olfactory dysfunction in COVID-19 patients was good as most cases recovered within a short period with concomitant smell exercise. Olfactory dysfunction in the majority of COVID-19 patients was self-limiting in young age groups, albeit in association with the non-severity of the disease. Being an important public health issue, examining olfactory dysfunction aspects should be considered in the diagnosis, prognosis, and treatment protocols of COVID-19 patients. In-depth exploration is needed to examine olfactory and gustatory dysfunction in patients suffering from severe COVID-19.

Exploring the Impact of COVID-19 on Ulcerative Colitis Patients: A Lifestyle Perspective

Background and Objectives: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 is the new coronavirus that caused the coronavirus disease 2019 (COVID-19) outbreak. Studies have increasingly reported the involvement of organs outside the respiratory system, including the gastrointestinal tract. Data on the association between COVID-19 and ulcerative colitis (UC) are lacking. Materials and Methods: In this one-centre cross-sectional study, 49 patients with UC from the Riga East Clinical University Hospital outpatient clinic were included from June 2021 to December 2021. The patients were divided into two groups according to their history of a confirmed positive or negative COVID-19 status. Data on their lifestyle, diet, and medications and the food supplements used by the patients were collected during interviews and analysed using the R 4.2.1 software. Results: Out of 49 patients, 33 (63.3%) were male and 13 (36.7%) were female, with a mean age of 32.33 ± 8.6 years. Fourteen patients (28.6%) had a confirmed COVID-19 infection in the last year. The most common COVID-19-related symptoms were a fever and rhinorrhoea. A third of patients followed the inflammatory bowel disease diet (16; 32.7%); out of these patients, 12 (34.3%) did not contract COVID-19 (OR: 0.78 (0.18; 2.98), p > 0.05). In the COVID-19-positive group, the majority of patients did not use vitamin D (11; 79% vs. 3; 21%, (OR: 0.38 (0.07; 1.51), p = 0.28) or probiotics (11; 78.6% vs. 3; 21.4%, OR: 1.33 (0.23; 6.28), p = 0.7). In the COVID-19-positive group, most patients did not smoke (12; 85.7% vs. 2; 14.3%, p = 0.475) and did not use alcohol (9; 64.3% vs. 5; 35.7%, OR: 0.63 (0.16; 2.57), p = 0.5). Most of the patients who participated in sports activities were COVID-negative (18; 51.4% vs. 6; 42.9%, p = 0.82). Conclusions: There were no statistically significant differences in the use of food supplements, probiotics, or vitamins; the lifestyle habits; or the COVID-19 status in patients with UC.

Study on the correlation between lifestyle and negative conversion time in patients diagnosed with coronavirus disease (COVID-19): a retrospective cohort study

BACKGROUND

As of early December 2022, China eased the coronavirus disease (COVID-19) restriction, affecting over 80% of the country's population and posing a severe threat to public health. Previous studies mostly focused factors on the severity/mortality rate of hospitalized COVID-19 patients, but limited studies explored factors associated with virus-negative conversion, particularly lifestyles. Therefore, the aim of our study was to analyze the correlation between lifestyle factors and the negative conversion time in COVID-19 patients.

METHODS

We recruited individuals aged 18 years or older who had a clear time record for both the diagnosis and negative conversion of COVID-19 and completed the electronic questionnaire with no missing data. Dietary data collected from the questionnaire was analyzed using exploratory factor analysis to establish dietary patterns. Age segmentation was performed using restricted cubic spline (RCS) plots. The association between lifestyle factors and the time to negative conversion in different age groups, was assessed using Kaplan-Meier plots and Cox regression analysis.

RESULT

Out of 514 participants, all achieved viral negative conversion within a median time of 11 days. Based on nutrient intake, we identified four dietary patterns. The relationship between age and negative conversion rate, as depicted by RCS plots, exhibited an inverted "U" shape. We categorized age into three segments: <35 years, 35-45 years, and ≥ 45 years. For individuals under 35, our study indicated that a higher protein intake was linked to a faster recovery among COVID-19 patients, while medical staff or those receiving prescription treatments exhibited a slower recovery rate (P < 0.05). The 35 ~ 45 age group showed that adequate sleep and physical exercise were associated with a shorter time to negative conversion, whereas southern regions and a higher intake of carbohydrates were related with a longer conversion time (P < 0.05). Among individuals aged ≥ 45 years, the negative conversion time was primarily associated with physical exercise and being a medical staff member(P < 0.05).

CONCLUSION

Our research suggests that adequate sleep, physical exercise and a higher protein intake can help alleviate COVID-19 symptoms, while a higher level of carbohydrates intake may hinder recovery from COVID-19.

Differential activation of programmed cell death in patients with severe SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes severe lower airway disease and death in a subset of patients. Knowledge on the relative contribution of programmed cell death (PCD) to lung pathology is limited to few human autopsy studies with small sample size/scope, in vitro cell culture, and experimental model systems. In this study, we sought to identify, localize, and quantify activation of apoptosis, ferroptosis, pyroptosis, and necroptosis in FFPE lung tissues from patients that died from severe SARS-CoV-2 infection (n = 28) relative to uninfected controls (n = 13). Immunofluorescence (IF) staining, whole-slide imaging, and Image J software was used to localize and quantify expression of SARS-CoV-2 nucleoprotein and the following PCD protein markers: cleaved Caspase-3, pMLKL, cleaved Gasdermin D, and CD71, respectively. IF showed differential activation of each PCD pathway in infected lungs and dichotomous staining for SARS-CoV-2 nucleoprotein enabling distinction between high (n = 9) vs low viral burden (n = 19). No differences were observed in apoptosis and ferroptosis in SARS-CoV-2 infected lungs relative to uninfected controls. However, both pyroptosis and necroptosis were significantly increased in SARS-CoV-2-infected lungs. Increased pyroptosis was observed in SARS-CoV-2 infected lungs, irrespective of viral burden, suggesting an inflammation-driven mechanism. In contrast, necroptosis exhibited a very strong positive correlation with viral burden (R2 = 0.9925), suggesting a direct SARS-CoV-2 mediated effect. These data indicate a possible novel mechanism for viral-mediated necroptosis and a potential role for both lytic programmed cell death pathways, necroptosis and pyroptosis, in mediating infection outcome.

Nicotine: From Discovery to Biological Effects

Nicotine, the primary psychoactive agent in tobacco leaves, has led to the widespread use of tobacco, with over one billion smokers globally. This article provides a historical overview of tobacco and discusses tobacco dependence, as well as the biological effects induced by nicotine on mammalian cells. Nicotine induces various biological effects, such as neoangiogenesis, cell division, and proliferation, and it affects neural and non-neural cells through specific pathways downstream of nicotinic receptors (nAChRs). Specific effects mediated by α7 nAChRs are highlighted. Nicotine is highly addictive and hazardous. Public health initiatives should prioritize combating smoking and its associated risks. Understanding nicotine's complex biological effects is essential for comprehensive research and informed health policies. While potential links between nicotine and COVID-19 severity warrant further investigation, smoking remains a significant cause of morbidity and mortality globally. Effective public health strategies are vital to promote healthier lifestyles.

COPD-Related Mortality before and after Mass COVID-19 Vaccination in Northern Italy

BACKGROUND/OBJECTIVE

Little is known about the impact of the COVID-19 pandemic on mortality from COPD at the population level. The objective was to investigate COPD-related mortality throughout different epidemic waves in Italy before and after the vaccination campaign, which started in late December 2020 and initially targeted the population aged ≥80 years.

METHODS

Death certificates of residents in Veneto (Northeastern Italy) aged ≥40 years between 2008 and 2021 were analyzed. Age-standardized morality rates were computed for death certificates with any mention of COPD. Generalized estimating equation (GEE) models were fitted to estimate the expected mortality during the pandemic. The results were stratified by age groups of 40-79 and ≥80 years, main comorbidities, and place of death.

RESULTS

COPD was mentioned in 3478 death certificates in 2020 (+14% compared to the 2018-2019 average) and in 3133 in 2021 (+3%). Age-standardized mortality rates increased in all age and sex groups in 2020; in 2021, mortality returned to pre-pandemic levels among the elderly but not in the population aged 40-79 years (+6%). GEE models confirmed this differential trend by age. COPD-related mortality peaks were observed, especially in the first pandemic waves, with COVID-19 identified as the underlying cause of death in a relevant proportion (up to 35% in November 2020-January 2021). Mortality with comorbid diabetes and hypertensive diseases slightly increased during the pandemic.

CONCLUSION

COPD-related mortality increased at the beginning of the pandemic, due to deaths from COVID-19. The start of the vaccination campaign was associated with an important decline in COPD-related mortality, especially among the elderly, who first benefited from COVID-19 vaccines. The study findings show the role of mass vaccination in reducing COPD-related deaths during the later phases of the pandemic.

The rs16969968 Tobacco Smoking-Related Single-Nucleotide Variant Is Associated with Clinical Markers in Patients with Severe COVID-19

Tobacco smoking is the leading risk factor for many respiratory diseases. Several genes are associated with nicotine addiction, such as CHRNA5 and ADAM33. This research aims to evaluate the association of the polymorphisms rs16969968 (CHRNA5) and rs3918396 (ADAM33) in patients who developed severe COVID-19. We included 917 COVID-19 patients hospitalized with critical disease and oxygenation impairment. They were divided into two groups, tobacco-smoking (n = 257) and non-smoker (n = 660) patients. The genotype and allele frequencies of two single nucleotide variants, the rs16969968 (CHRNA5) and rs3918396 (ADAM33), were evaluated. The rs3918396 in ADAM33 does not show a significative association. We analyzed the study population according to the rs16969968 genotype (GA + AA, n = 180, and GG, n = 737). The erythrocyte sedimentation rate (ESR) shows statistical differences; the GA + AA group had higher values than the GG group (p = 0.038, 32 vs. 26 mm/h, respectively). The smoking patients and GA or AA genotype carriers had a high positive correlation (p < 0.001, rho = 0.753) between fibrinogen and C-reactive protein. COVID-19 patients and smokers carriers of one or two copies of the risk allele (rs16969968/A) have high ESR and a positive correlation between fibrinogen and C-reactive protein.