Rapid Weight Loss, Central Obesity Improvement and Blood Glucose Reduction Are Associated with a Stronger Adaptive Immune Response Following COVID-19 mRNA Vaccine

Safety and efficiency of COVID-19 vaccine in North Africa

Background In the absence of a specific treatment for COVID-19, preventive measures have been implemented to control this pandemic and vaccination is one of them. However, it is crucial to verify the safety and efficiency of every vaccine. The aim was to determinate the predictive factors of side effects and reinfection after COVID-19 vaccine. Methods A cross-sectional study was conducted in February 2022 among Tunisians infected with COVID-19 between March 2020 and February 2022, using an online self-administered questionnaire. We conducted univariate and multivariate analyses using binary stepwise logistic regression. Results A total of 1541 was selected from 1911 individuals. Comorbidities affected a quarter of the population (22.3%). Before the initial infection, 39.3% had received full vaccination, and 8.7% had received partial vaccination. By February 2022, the majority (82.9%) had received at least two vaccine doses. The reinfection rate was 30.6%. All vaccines prior to the first infection was identified as a protective factor against reinfection. Inactivated virus vaccinations were less likely to induce adverse effects. Conclusion ach vaccine has its own set of advantages and disadvantages: mRNA-based vaccines had a higher incidence of side effects but all vaccines provided better protection against reinfection.

The role of plant-based dietary patterns in reducing COVID-19 risk and/or severity in adults: A systematic review and meta-analysis of observational studies

BACKGROUND & AIMS

Plant-based dietary patterns (PBDs) might protect against COVID-19 risk and reduce severity of infection. This systematic review with meta-analysis aimed to examine the association between PBDs and risk of COVID-19 infection, hospitalization, intensive care unit (ICU) admission, and/or mortality, in adults.

METHODS

Pubmed, Embase, CINAHL and Web of Science were searched for observational studies, published in English up to 3rd April 2023, comparing the highest with the lowest adherence to a specific PBD. Data were screened, extracted, and risk of bias assessed using the Newcastle-Ottawa Quality Assessment Scale, by independent reviewers.

RESULTS

Seven studies (one cross-sectional, three case-control, and three prospective cohort), reporting on 649,315 participants, were eligible. Across them, there were 8512 events of COVID-19 infection (six studies), and 206 events of COVID-19 hospitalization (four studies), in addition to one study reporting on a composite hospitalization outcome (740 events). The pooled analysis showed that PBDs are associated with a 59% (odds ratio (OR) = 0.41, 95% confidence intervals (CI) 0.23-0.59; two studies) and 18% (OR = 0.82, 95% CI 0.78-0.85; three studies) reduction in COVID-19 infection risk in case-control and cohort studies, respectively. The pooled analysis of one case-control and two cohort studies showed an inverse association between high adherence to a PBD and risk of COVID-19 hospitalization (OR = 0.38, 95% CI 0.04-0.72).

CONCLUSION

Findings suggest a protective role of PBDs against the risk of COVID-19 infection and severity. More studies are needed to establish the association between PBDs and risk of ICU admission and mortality due to COVID-19.

Mortality risk in patients with obesity and COVID-19 infection: a systematic review and meta-analysis

Obesity is a risk factor for severe respiratory diseases, including COVID-19 infection. Meta-analyses on mortality risk were inconsistent. We systematically searched 3 databases (Medline, Embase, CINAHL) and assessed the quality of studies using the Newcastle-Ottawa tool (CRD42020220140). We included 199 studies from US and Europe, with a mean age of participants 41.8-78.2 years, and a variable prevalence of metabolic co-morbidities of 20-80 %. Exceptionally, one third of the studies had a low prevalence of obesity of <20 %. Compared to patients with normal weight, those with obesity had a 34 % relative increase in the odds of mortality (p-value 0.002), with a dose-dependent relationship. Subgroup analyses showed an interaction with the country income. There was a high heterogeneity in the results, explained by clinical and methodologic variability across studies. We identified one trial only comparing mortality rate in vaccinated compared to unvaccinated patients with obesity; there was a trend for a lower mortality in the former group. Mortality risk in COVID-19 infection increases in parallel to an increase in BMI. BMI should be included in the predictive models and stratification scores used when considering mortality as an outcome in patients with COVID-19 infections. Furthermore, patients with obesity might need to be prioritized for COVID-19 vaccination.

BNT162b2 Booster Dose Elicits a Robust Antibody Response in Subjects with Abdominal Obesity and Previous SARS-CoV-2 Infection

Little is known about the long-term durability of the induced immune response in subjects with obesity, particularly in those with an abdominal distribution of adipose tissue. We evaluated SARS-CoV-2-specific antibody responses after BNT162b2 vaccine booster dose, comparing individuals with and without abdominal obesity (AO), discerning between individuals previously infected or not. IgG-TrimericS were measured in 511 subjects at baseline, on the 21st day after vaccine dose 1, and at 1, 3, 6, and 9 months from dose 2, and at 1 and 3 months following the booster dose. To detect SARS-CoV-2 infection, nucleocapsid antibodies were measured at baseline and at the end of the study. Multivariable linear regression evaluated the three-month difference in the absolute variation in IgG-TrimericS levels from booster dose, showing AO and SARS-CoV-2 infection status interactions (p = 0.016). Regardless of possible confounding factors and IgG-TrimericS levels at the booster dose, AO is associated with a higher absolute change in IgG-TrimericS in prior infected individuals (p = 0.0125). In the same regression model, no interaction is highlighted using BMI (p = 0.418). The robust response in the development of antibodies after booster dose, observed in people with AO and previous infection, may support the recommendations to administer a booster dose in this population group.

Dose Intervals and Time since Final Dose on Changes in Metabolic Indices after COVID-19 Vaccination

The rapid development and implementation of COVID-19 vaccines merit understanding its effects on metabolic indices. This retrospective longitudinal study investigated the influence of first-to-second-dose intervals and time since the final dose on the metabolic indices of individuals receiving COVID-19 vaccinations. A total of 318 Saudi subjects (59.7% females) aged 12-60 years received COVID-19 vaccines via the national vaccination program. We collected the anthropometric data and fasting blood samples at specific time points before vaccination and after the final vaccination dose, and biochemical metabolic indices, including glucose and lipid profile, were measured. We also collected the dates of vaccination and COVID-19 history during the study period. The participants were stratified into groups based on first-to-second-dose intervals and time since the final dose to compare pre-and post-vaccination changes in metabolic indices between the groups. Logistic regression analysis revealed no differences in pre- to post-vaccination metabolic status between groups based on first-to-second-dose intervals in either adolescents or adults. However, shorter intervals (≤6 months) between the final dose and follow-up were associated with a decrease in total cardiometabolic components, especially triglyceride levels (OR = 0.39, 95% CI: (0.22-0.68), p < 0.001) than longer intervals (>6 months) in adults. In conclusion, time duration since final dose was associated with pre- to post-vaccination changes in metabolic indices, especially triglyceride levels, indicating that post-vaccination improvements wane over time. Further research is needed to validate the observed relationship, as it may contribute to optimizing vaccine effectiveness and safety in the future.

Editorial for "The Role of Ketogenic Diet in Human Health and Diseases": The Multifaceted Impact of Ketogenic Diets on Health and Disease

The ketogenic diet (KD), characterized by a very low carbohydrate intake and variable protein, fat and calorie intake, has long been in the spotlight for its potential therapeutic applications [...].

The Safety and Effectiveness of mRNA Vaccines Against SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in numerous deaths worldwide, along with devastating economic disruptions, and has posed unprecedented challenges to healthcare systems around the world. In the wake of COVID-19's emergence in 2019, a variety of vaccine technologies were formulated and developed, including those that drew from the technology employed in messenger RNA (mRNA) vaccines, designed to curb the disease's transmission and manage the pandemic. mRNA vaccine has several advantages over traditional ones, and hence its development has received considerable attention recently. Researchers believe the mRNA vaccine technology will emerge as the leading technology because it is potent, inexpensive, rapidly developed, and safe. This article provides an overview of mRNA vaccines with a special focus on the efficacy and safety of the Moderna and Pfizer-BioNTech mRNA vaccines against the different variants of COVID-19 and compare them with the Oxford-AstraZeneca (viral vector) and Sinopharm (inactivated virus) vaccines. The clinical data reviewed in this article demonstrate that the currently authorized Moderna and Pfizer-BioNTech mRNA vaccines are highly safe and potent against different variants of COVID-19, especially in comparison with Oxford-AstraZeneca (viral vector) and Sinopharm (inactivated virus) vaccines.

Influence of the Single Nucleotide Polymorphisms rs12252 and rs34481144 in IFITM3 on the Antibody Response after Vaccination against COVID-19

The COVID-19 mRNA vaccine is the first mRNA vaccine approved for human administration by both the U.S. Food and Drug Administration and the European Medicines Agency. Studies have shown that the immune response and the decay of immunity after vaccination with the COVID-19 vaccines are variable within a population. Host genetic factors probably contribute to this variability. In this study, we investigated the effect of the single-nucleotide polymorphisms rs12252 and rs34481144 in the interferon-induced transmembrane protein (IFITM) 3 gene on the humoral immune response after vaccination against COVID-19 with mRNA vaccines. Blood samples were collected from 1893 healthcare workers and medical students at multiple time points post-vaccination and antibody titers against the SARS-CoV-2 S1 protein receptor binding domain were determined at all time points. All participants were genotyped for the rs34481144 and rs12252 polymorphisms in the IFITM3 gene. After the second and third vaccinations, antibody titer levels increased at one month and decreased at six months (p < 0.0001) and were higher after the booster vaccination than after the basic immunization (p < 0.0001). Participants vaccinated with mRNA-1273 had a higher humoral immune response than participants vaccinated with BNT162b2. rs12252 had no effect on the antibody response. In contrast, carriers of the GG genotype in rs34481144 vaccinated with BNT162b2 had a lower humoral immune response compared to A allele carriers, which reached statistical significance on the day of the second vaccination (p = 0.03) and one month after the second vaccination (p = 0.04). Further studies on the influence of rs12252 and rs34481144 on the humoral immune response after vaccination against COVID-19 are needed.

Association between Overweight/Obesity and the Safety and Efficacy of COVID-19 Vaccination: A Systematic Review

OBJECTIVE

The objective of this study was to appraise the interrelation between overweight/obesity and the safety and efficacy of COVID-19 vaccination by synthesizing the currently available evidence.

METHODS

A systematic review of published studies on the safety and efficacy of the COVID-19 vaccine in people who were overweight or obese was conducted. Databases including Embase, Medline Epub (Ovid), PsychInfo (Ovid), Web of Science, PubMed, CINAHL, and Google Scholar were searched to identify relevant studies. The databases of the Centers for Disease Control (CDC) and World Health Organization (WHO) were also searched for relevant unpublished and gray literature.

RESULTS

Fifteen studies were included in the review. All the included studies used observational study designs; there were ten cohort studies and five cross-sectional studies. The sample size of these studies ranged from 21 to 9,171,524. Thirteen studies reported using BNT162b2 (Pfizer-BioNTech, USA), four reported using ChAdOx-nCov19 (AstraZeneca, U.K), two were reported using CoronaVac (Sinovac, China), and two were reported using mRNA1273 (Moderna, USA). The efficacy and safety of COVID-19 vaccines have been extensively studied in individuals with overweight/obesity. Most studies have shown that the humoral response decreases with increasing BMI. The available evidence does not conclusively indicate that these vaccines are generally safe in this population.

CONCLUSION

While the efficacy of the COVID-19 vaccine may be less than ideal in people who are overweight or obese, it does not mean that obese people should not be vaccinated, as the vaccine can still provide some protection. There is a lack of evidence for conclusions to be drawn about the safety of the vaccine in the population. This study calls on health professionals, policymakers, caregivers, and all other stakeholders to focus on monitoring the possible adverse effects of injections in overweight/obese people.

Metabolic Adaptations Correlated with Antibody Response after Immunization with Inactivated SARS-CoV-2 in Brazilian Subjects

The adsorbed vaccine SARS-CoV-2 (inactivated) produced by Sinovac (SV) was the first vaccine against COVID-19 to be used in Brazil. To understand the metabolic effects of SV in Brazilian subjects, NMR-based metabolomics was used, and the immune response was studied in Brazilian subjects. Forty adults without (group^-, n = 23) and with previous COVID-19 infection (group⁺, n = 17) were followed-up for 90 days postcompletion of the vaccine regimen. After 90 days, our results showed that subjects had increased levels of lipoproteins, lipids, and N-acetylation of glycoproteins (NAG) as well as decreased levels of amino acids, lactate, citrate, and 3-hydroxypropionate. NAG and threonine were the highest correlated metabolites with N and S proteins, and neutralizing Ab levels. This study sheds light on the immunometabolism associated with the use of SV in Brazilian subjects from Rio de Janeiro and identifies potential metabolic markers associated with the immune status.

Maintained imbalance of triglycerides, apolipoproteins, energy metabolites and cytokines in long-term COVID-19 syndrome patients

Background

Deep metabolomic, proteomic and immunologic phenotyping of patients suffering from an infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have matched a wide diversity of clinical symptoms with potential biomarkers for coronavirus disease 2019 (COVID-19). Several studies have described the role of small as well as complex molecules such as metabolites, cytokines, chemokines and lipoproteins during infection and in recovered patients. In fact, after an acute SARS-CoV-2 viral infection almost 10-20% of patients experience persistent symptoms post 12 weeks of recovery defined as long-term COVID-19 syndrome (LTCS) or long post-acute COVID-19 syndrome (PACS). Emerging evidence revealed that a dysregulated immune system and persisting inflammation could be one of the key drivers of LTCS. However, how these biomolecules altogether govern pathophysiology is largely underexplored. Thus, a clear understanding of how these parameters within an integrated fashion could predict the disease course would help to stratify LTCS patients from acute COVID-19 or recovered patients. This could even allow to elucidation of a potential mechanistic role of these biomolecules during the disease course.

Methods

This study comprised subjects with acute COVID-19 (n=7; longitudinal), LTCS (n=33), Recov (n=12), and no history of positive testing (n=73). ¹H-NMR-based metabolomics with IVDr standard operating procedures verified and phenotyped all blood samples by quantifying 38 metabolites and 112 lipoprotein properties. Univariate and multivariate statistics identified NMR-based and cytokine changes.

Results

Here, we report on an integrated analysis of serum/plasma by NMR spectroscopy and flow cytometry-based cytokines/chemokines quantification in LTCS patients. We identified that in LTCS patients lactate and pyruvate were significantly different from either healthy controls (HC) or acute COVID-19 patients. Subsequently, correlation analysis in LTCS group only among cytokines and amino acids revealed that histidine and glutamine were uniquely attributed mainly with pro-inflammatory cytokines. Of note, triglycerides and several lipoproteins (apolipoproteins Apo-A1 and A2) in LTCS patients demonstrate COVID-19-like alterations compared with HC. Interestingly, LTCS and acute COVID-19 samples were distinguished mostly by their phenylalanine, 3-hydroxybutyrate (3-HB) and glucose concentrations, illustrating an imbalanced energy metabolism. Most of the cytokines and chemokines were present at low levels in LTCS patients compared with HC except for IL-18 chemokine, which tended to be higher in LTCS patients.

Conclusion

The identification of these persisting plasma metabolites, lipoprotein and inflammation alterations will help to better stratify LTCS patients from other diseases and could help to predict ongoing severity of LTCS patients.

Early humoral response to COVID-19 vaccination in patients living with obesity and diabetes in France. The COVPOP OBEDIAB study with results from the ANRS0001S COV-POPART cohort

BACKGROUND

Patients with diabetes and obesity are populations at high-risk for severe COVID-19 outcomes and have shown blunted immune responses when administered different vaccines. Here we used the 'ANRS0001S COV-POPART' French nationwide multicenter prospective cohort to investigate early humoral response to COVID-19 vaccination in the sub-cohort ('COVPOP OBEDIAB') of patients with obesity and diabetes.

METHODS

Patients with diabetes (n = 390, type 1 or 2) or obesity (n = 357) who had received two vaccine doses and had no history of previous COVID-19 infection and negative anti-nucleocapsid (NCP) antibodies were included and compared against healthy subjects (n = 573). Humoral response was assessed at baseline, at one month post-first dose (M0) and one-month post-second dose (M1), through percentage of responders (positive anti-spike SARS-CoV-2 IgG antibodies (Sabs), geometric means of Sabs; BAU/mL), proportion of individuals with anti-RBD antibodies, and proportion of individuals with anti-SARS-CoV-2-specific neutralizing antibodies (Nabs). Potential clinical and biological factors associated with weak response (defined as Sabs < 264 BAU/mL) and presence of non-reactive anti-RBD antibodies at M1 were evaluated. Univariate and multivariate regressions were performed to estimate crude and adjusted coefficients with 95 % confidence intervals. Poor glycemic control was defined as HbA1c ≥ 7.5 % at inclusion.

RESULTS

Patients with diabetes, particularly type 2 diabetes, and patients with obesity were less likely to have positive Sabs and anti-RBD antibodies after the first and second dose compared to controls (p < 0.001). At M1, we found Sabs seroconversion in 94.1 % of patients with diabetes versus 99.7 % in controls, anti-RBD seroconversion in 93.8 % of patients with diabetes versus 99.1 % in controls, and Nabs seroconversion in 95.7 % of patients with diabetes versus 99.6 % in controls (all p < 0.0001). Sabs and anti-RBD seroconversion at M0 and M1 were also significantly lower in obese patients than controls, at respectively 82.1 % versus 89.9 % (p = 0.001; M0 Sabs), 94.4 % versus 99.7 % (p 0.001; M1 Sabs), 79.0 % vs 86.2 % (p = 0.004 M0 anti-RBD), and 96.99 % vs 99.1 % (p = 0.012 M1 anti-RBD). The factors associated with low vaccine response (BAU < 264/mL) in patients with diabetes were chronic kidney disease (adjusted OR = 6.88 [1.77;26.77], p = 0.005) and poor glycemic control (adjusted OR = 3.92 [1.26;12.14], p = 0.018). In addition, BMI ≥ 40 kg/m² was found to be associated with a higher vaccine response (adjusted OR = 0.10 [0.01;0.91], p = 0.040) than patients with BMI < 40 kg/m².

CONCLUSION

COVID-19 vaccine humoral response was lower in patients with obesity and diabetes one month after second dose compared to controls, especially in diabetic patients with CKD or inadequate glycemic control. These findings point to the need for post-vaccination serological checks in these high-risk populations.

Elicitation of potent neutralizing antibodies in obese mice by ISA 51-adjuvanted SARS-CoV-2 spike RBD-Fc vaccine

Vaccination is considered to be the most effective countermeasure to prevent and combat the global health threats of COVID-19. People with obesity are at a greater risk of hospitalization, life-threatening illness, and adverse outcomes after having COVID-19. Therefore, a safe and effective COVID-19 vaccine for obese individuals is urgently needed. In the study, the vaccine composed of the ISA 51 adjuvant and the SARS-CoV-2 spike (S) receptor-binding domain (RBD) in conjugation with the human IgG1 Fc fragment (named as ISA 51-adjuvanted RBD-Fc vaccine) was developed and inoculated in the regular chow diet (RCD) lean mice and the high-fat diet (HFD)-induced obese mice. The S protein-specific IgG titers were largely induced in an increasing manner along with three doses of ISA 51-adjuvanted RBD-Fc vaccine without causing any harmful side effect. In the HFD mice, the S protein-specific IgG titers can be quickly observed 2 weeks post the first inoculation. The antisera elicited by the ISA 51-adjuvanted RBD-Fc vaccine in the RCD and HFD mice exhibited potent SARS-CoV-2 neutralizing activities in the plaque reduction neutralization test (PRNT) assays and showed similar specificity for recognizing the key residues in the RBD which were involved in interacting with angiotensin-converting enzyme 2 (ACE2) receptor. The immune efficacy of the ISA 51-adjuvanted RBD-Fc vaccine in the HFD mice can be sustainably maintained with the PRNT50 values of 1.80-1.91×10^-3 for at least 8 weeks post the third inoculation. Collectively, the RBD-Fc-based immunogen and the ISA 51-adjuvanted formulation can be developed as an effective COVID-19 vaccine for obese individuals. KEY POINTS: • The ISA 51-adjuvanted RBD-Fc vaccine can induce potent SARS-CoV-2 neutralizing antibodies in the obese mouse • The antibodies elicited by the ISA 51-adjuvanted RBD-Fc vaccine can bind to the key RBD residues involved in interacting with ACE2 • The immune efficacy of the ISA 51-adjuvanted RBD-Fc vaccine can be sustainably maintained for at least 8 weeks post the third inoculation.

Comment on Sung et al. Body Fat Reduction Effect of Bifidobacterium breve B-3: A Randomized, Double-Blind, Placebo Comparative Clinical Trial. Nutrients 2023, 15, 28

I read with interest the paper by Sung et al. entitled "Body Fat Reduction Effect of Bifidobacterium breve B-3: A Randomized, Double-Blind, Placebo Comparative Clinical Trial" where a reduction in body fat mass after Bifidobacterium breve B-3 (BB-3) ingestion for 12 weeks was reported [...].

Predictors of weight loss in patients with obesity treated with a Very Low-Calorie Ketogenic Diet

Introduction

The Very Low-Calorie Ketogenic Diet (VLCKD) has emerged as a safe and effective intervention for the management of metabolic disease. Studies examining weight loss predictors are scarce and none has investigated such factors upon VLCKD treatment. Among the molecules involved in energy homeostasis and, more specifically, in metabolic changes induced by ketogenic diets, Fibroblast Growth Factor 21 (FGF21) is a hepatokine with physiology that is still unclear.

Methods

We evaluated the impact of a VLCKD on weight loss and metabolic parameters and assessed weight loss predictors, including FGF21. VLCKD is a severely restricted diet (<800 Kcal/die), characterized by a very low carbohydrate intake (<50 g/day), 1.2-1.5 g protein/kg of ideal body weight and 15-30 g of fat/day. We treated 34 patients with obesity with a VLCKD for 45 days. Anthropometric parameters, body composition, and blood and urine chemistry were measured before and after treatment.

Results

We found a significant improvement in body weight and composition and most metabolic parameters. Circulating FGF21 decreased significantly after the VLCKD [194.0 (137.6-284.6) to 167.8 (90.9-281.5) p < 0.001] and greater weight loss was predicted by lower baseline FGF21 (Beta = -0.410; p = 0.012), male sex (Beta = 0.472; p = 0.011), and central obesity (Beta = 0.481; p = 0.005).

Discussion

VLCKD is a safe and effective treatment for obesity and obesity related metabolic derangements. Men with central obesity and lower circulating FGF21 may benefit more than others in terms of weight loss obtained following this diet. Further studies investigating whether this is specific to this diet or to any caloric restriction are warranted.

Metabolic syndrome and aberrant immune responses to viral infection and vaccination: Insights from small animal models

This review outlines the propensity for metabolic syndrome (MetS) to induce elevated disease severity, higher mortality rates post-infection, and poor vaccination outcomes for viral pathogens. MetS is a cluster of conditions including high blood glucose, an increase in circulating low-density lipoproteins and triglycerides, abdominal obesity, and elevated blood pressure which often overlap in their occurrence. MetS diagnoses are on the rise, as reported cases have increased by greater than 35% since 1988, resulting in one-third of United States adults currently diagnosed as MetS patients. In the aftermath of the 2009 H1N1 pandemic, a link between MetS and disease severity was established. Since then, numerous studies have been conducted to illuminate the impact of MetS on enhancing virally induced morbidity and dysregulation of the host immune response. These correlative studies have emphasized the need for elucidating the mechanisms by which these alterations occur, and animal studies conducted as early as the 1940s have linked the conditions associated with MetS with enhanced viral disease severity and poor vaccine outcomes. In this review, we provide an overview of the importance of considering overall metabolic health in terms of cholesterolemia, glycemia, triglyceridemia, insulin and other metabolic molecules, along with blood pressure levels and obesity when studying the impact of metabolism-related malignancies on immune function. We highlight the novel insights that small animal models have provided for MetS-associated immune dysfunction following viral infection. Such animal models of aberrant metabolism have paved the way for our current understanding of MetS and its impact on viral disease severity, dysregulated immune responses to viral pathogens, poor vaccination outcomes, and contributions to the emergence of viral variants.

Body fat percentage is independently and inversely associated with serum antibody responses to SARS-CoV-2 mRNA vaccines

Vaccination is widely considered the most effective preventative strategy to protect against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. An individual's exercise habits, and physical fitness have been shown to impact the immune response following vaccination using traditional vaccine platforms, but their effects are not well characterized following administration of newer vaccination technology (mRNA vaccines). We investigated these effects on the magnitude of antibody responses following SARS-CoV-2 mRNA vaccination while accounting for known covariates (age, sex, time since vaccination, and the type of vaccine administered). Adults of varying fitness levels (18-65 years; N = 50) who had received either the Moderna or Pfizer SARS-CoV-2 mRNA vaccine between 2 weeks and 6 months prior, completed health history and physical activity questionnaires, had their blood drawn, body composition, cardiorespiratory fitness, and strength assessed. Multiple linear regressions assessed the effect of percent body fat, hand grip strength, cardiorespiratory fitness, and physical activity levels on the magnitude of receptor binding domain protein (RBD) and spike protein subunit 1 (S1) and 2 (S2) while accounting for known covariates. Body fat percentage was inversely associated with the magnitude of S1 (p = 0.006, β = - 366.56), RBD (p = 0.003, β = - 249.30), and S2 (p = 0.106, β = - 190.08) antibodies present in the serum following SARS-CoV-2 mRNA vaccination. Given the increasing number of infections, variants, and the known waning effects of vaccination, future mRNA vaccinations such as boosters are encouraged to sustain immunity; reducing excess body fat may improve the efficacy of these vaccinations.

Visceral adipose tissue and risk of COVID-19 susceptibility, hospitalization, and severity: A Mendelian randomization study

Background

Coronavirus Disease 2019 (COVID-19) has rapidly evolved as a global pandemic. Observational studies found that visceral adipose tissue (VAT) increased the likelihood of worse clinical outcomes in COVID-19 patients. Whereas, whether VAT is causally associated with the susceptibility, hospitalization, or severity of COVID-19 remains unconfirmed. We aimed to investigate the causal associations between VAT and susceptibility, hospitalization, and severity of COVID-19.

Methods

We applied a two-sample Mendelian randomization (MR) study to infer causal associations between VAT and COVID-19 outcomes. Single-nucleotide polymorphisms significantly associated with VAT were derived from a large-scale genome-wide association study. The random-effects inverse-variance weighted method was used as the main MR approach, complemented by three other MR methods. Additional sensitivity analyses were also performed.

Results

Genetically predicted higher VAT mass was causally associated with higher risks of COVID-19 susceptibility [odds ratios (ORs) = 1.13; 95% confidence interval (CI), 1.09-1.17; P = 4.37 × 10^-12], hospitalization (OR = 1.51; 95% CI = 1.38-1.65; P = 4.14 × 10^-20), and severity (OR = 1.58; 95% CI = 1.38-1.82; P = 7.34 × 10^-11).

Conclusion

This study provided genetic evidence that higher VAT mass was causally associated with higher risks of susceptibility, hospitalization, and severity of COVID-19. VAT can be a useful tool for risk assessment in the general population and COVID-19 patients, as well as an important prevention target.

SARS-CoV-2 and Influenza Vaccines in People with Excessive Body Mass-A Narrative Review

In the face of a growing number of overweight people and two widely known viral diseases, SARS-CoV-2 and influenza, it is crucial to be aware of the impact of excess body weight on immunisation against these diseases. The aim of this review is to show the effectiveness of SARS-CoV-2 and influenza vaccines in overweight and obese patients. Excessive adipose tissue releases cytokines and maintains local hypoxia, which causes persistent low-grade inflammation. These factors make excess body mass patients' immune systems weaker. Under such conditions, the humoral response becomes less efficient, leading to a weakened ability to fight against infection and an increased risk of developing lower antibody titres. Vaccines help to reduce morbidity both in normal-weight and excess body mass people, although most studies show that patients with higher BMI tend to lose the antibodies produced more quickly. It is shown that the most effective vaccines (in terms of preventing the infection and potential post-illness complications) are the BNT162b2 vaccine against SARS-CoV-2 and the inactivated influenza vaccine against influenza among both obese and non-obese subjects.

Hypogammaglobulinemia is associated with reduced antibody response after anti-SARS-CoV-2 vaccination in MS patients treated with antiCD20 therapies

Background

Methods

Results

Conclusion

Use of heated tobacco products, moderate alcohol drinking, and anti-SARS-CoV-2 IgG antibody titers after BNT162b2 vaccination among Japanese healthcare workers

The effect of heated tobacco products (HTPs) use and moderate alcohol drinking on immunogenicity to coronavirus disease (COVID-19) vaccines remain elusive. This study aimed to examine the association of tobacco product use and alcohol consumption with anti-SARS-CoV-2 spike IgG antibody titers after the BNT162b2 vaccine. Participants were 3433 healthcare workers receiving two vaccine doses in the 4 national centers for advanced medical and research in Japan. Smoking status and alcohol consumption were assessed via a questionnaire, and anti-SARS-CoV-2 spike IgG titers were measured with chemiluminescent enzyme immunoassay using serum collected on the median of 64 days after the second vaccination. Multilevel linear regression models were used to estimate the geometric mean titers (GMT) and the ratios of means (RoM) between groups with adjustment for covariates. Compared with never-smokers (GMT = 118), IgG antibody titers were significantly lower among HTPs users (including those who also smoked cigarettes) (GMT = 105; RoM = 0.89 [95%CI: 0.78-0.99]) and exclusive cigarettes smokers (GMT = 98; RoM = 0.81 [95%CI: 0.71-0.92]). Compared with non-drinkers of alcohol (GMT = 123), alcohol drinkers consuming <1 go/day (GMT = 113; RoM = 0.93 [95%CI: 0.88-0.98]), 1-1.9 go/day (GMT = 104; RoM = 0.85 [95%CI: 0.78-0.93]), and ≥ 2 go/day (GMT = 103; RoM = 0.84 [95%CI: 0.74-0.96]) had significantly lower antibody titers (P for trend<0.01). Spline analysis showed a large reduction of antibody until around 1 go/day of alcohol consumption, and then they gradually decreased. Results suggest that in addition to conventional cigarette smoking and heavy alcohol drinking, HTPs use and moderate alcohol drinking may be predictors of lower immunological response to COVID-19 vaccine.

Antibody Response to SARS-CoV-2 Vaccines in People with Severe Obesity

AIM

Obesity is a disease complicating the course of COVID-19 and SARS-CoV-2 vaccine effectiveness in adults with obesity may be compromised. Our aim is to investigate the spike-protein receptor-binding domain antibody titers against BNT162b2 mRNA and inactivated SARS-CoV-2 (CoronaVac) vaccines in people with severe obesity. It is anticipated that the results to be obtained may provide invaluable information about future SARS-CoV-2 vaccination strategies in this vulnerable population.

METHODS

A total of 124 consecutive patients with severe obesity (age > 18 years, BMI ≥ 40 kg/m²) presenting between August and November 2021 were enrolled. The normal weight control group (age > 18, BMI 18.5-24.9 kg/m²) was recruited from 166 subjects who visited the vaccination unit. SARS-CoV-2 spike-protein antibody titers were measured in patients with severe obesity and in normal weight controls who received two doses of BNT162b2, or CoronaVac vaccines. SARS-CoV-2 IgG Nucleocapsid Protein antibody (NCP Ab) testing was performed to discover prior SARS-CoV-2 infection. Blood samples were taken from individuals at 4th week and after 2nd dose of vaccination. SARS-CoV-2 IgG antibody titers were determined by quantitative serological methods.

RESULTS

A total of 290 individuals (220 female, 70 male) who have received two doses of BNT162b2 or CoronaVac vaccines were enrolled in the study. Seventy had prior SARS-CoV-2 infection. In 220 subjects (non-prior infection) vaccinated with BNT162b2 or CoronaVac, the antibody titers against SARS-CoV-2 spike antigen of patients with severe obesity were significantly lower than normal weight controls (p = 0.001, p = 0.001 respectively). In seventy subjects with prior SARS-CoV-2 infection, spike antigen antibody titers in patients with severe obesity, vaccinated with BNT162b2 or CoronaVac, were not significantly different from normal weight controls (p = 0.1, p = 0.1 respectively). In patients with severe obesity, with and without prior SARS-CoV-2 infection, spike antigen antibody levels of those vaccinated with BNT162b2 were found to be significantly higher than those vaccinated with CoronaVac (p = 0.043, p < 0.001 respectively).

CONCLUSION

Patients with severe obesity generated significantly reduced antibody titers against SARS-CoV-2 spike antigen after CoronaVac and BNT162b2 vaccines compared to people with normal weight. Antibody levels in patients with severe obesity vaccinated with BNT162b2 were found to be significantly higher than those vaccinated with CoronaVac. People living with severe obesity should be prioritized for COVID-19 vaccination and BNT162b2 vaccine may be recommended for this vulnerable population.

Impact of Obesity on Vaccination to SARS-CoV-2

To combat the immense toll on global public health induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), new vaccines were developed. While these vaccines have protected the populations who received them from severe SARS-CoV-2 infection, the effectiveness and durability of these vaccines in individuals with obesity are not fully understood. Our uncertainty of the ability of these novel vaccines to induce protective immunity in humans with obesity stems from historical data that revealed obesity-associated immune defects to influenza vaccines. This review analyzes the efficacy of SARS-CoV-2 vaccines in humans with obesity. According to the vaccine safety and efficacy information for the Pfizer, Moderna, and Johnson & Johnson formulations, these vaccines showed a similar efficacy in both individuals with and without obesity. However, clinical trials that assess BMI and central obesity showed that induced antibody titers are lower in individuals with obesity when compared to healthy weight subjects, highlighting a potential early waning of vaccine-induced antibodies linked to obesity rates. Thus, the desired protective effects of SARS-CoV-2 vaccination were potentially diminished in humans with obesity when compared to the healthy weight population, but further studies outlining functional implications of the link between obesity and lower antibody titers need to be conducted to understand the full impact of this immune phenomenon. Further, additional research must be completed to truly understand the immune responses mounted against SARS-CoV-2 in patients with obesity, and whether these responses differ from those elicited by previously studied influenza viruses.