Hospitalized prenatal and childhood infections and obesity in Danish male conscripts

Offspring cardiometabolic outcomes and postnatal growth trajectories after exposure to maternal SARS-CoV-2 infection

OBJECTIVE

The objective of this study is to determine whether in utero exposure to SARS-CoV-2 is associated with increased risk for a cardiometabolic diagnosis by 18 months of age.

METHODS

This retrospective electronic health record (EHR)-based cohort study included the live-born offspring of all individuals who delivered during the COVID-19 pandemic (April 1, 2020-December 31, 2021) at eight hospitals in Massachusetts. Offspring exposure was defined as a positive maternal SARS-CoV-2 polymerase chain reaction test during pregnancy. The primary outcome was presence of an ICD-10 code for a cardiometabolic disorder in offspring EHR by 18 months. Weight-, length-, and BMI-for-age z scores were calculated and compared at 6-month intervals from birth to 18 months.

RESULTS

A total of 29,510 offspring (1599 exposed and 27,911 unexposed) were included. By 18 months, 6.7% of exposed and 4.4% of unexposed offspring had received a cardiometabolic diagnosis (crude odds ratio [OR] 1.47 [95% CI: 1.10 to 1.94], p = 0.007; adjusted OR 1.38 [1.06 to 1.77], p = 0.01). Exposed offspring had a significantly greater mean BMI-for-age z score versus unexposed offspring at 6 months (z score difference 0.19 [95% CI: 0.10 to 0.29], p < 0.001; adjusted difference 0.04 [-0.06 to 0.13], p = 0.4).

CONCLUSIONS

Exposure to maternal SARS-CoV-2 infection was associated with an increased risk of receiving a cardiometabolic diagnosis by 18 months preceded by greater BMI-for-age at 6 months.

Body Mass Index and Antibody Persistence after Measles, Mumps, Rubella and Hepatitis B Vaccinations

Overweight and obesity may cause a reduced response to vaccination. The purpose of the present research was to study the relationship between current body mass index (BMI) and antibody persistence after vaccination against measles, mumps, and rubella (MMR) and hepatitis B virus (HBV) given during childhood, as per the current vaccination schedule. The study was conducted on 2185 students at the School of Medicine, University of Padua, Italy. The mean age of the participants was 20.3 years. After adjusting for sex, age at first dose of vaccine administered, age at last dose, and age at study enrollment, no significant association was found between lack of serologic protection and BMI for either the HBV vaccine or each component of the MMR vaccine. For the first time, the absence of this relationship was demonstrated for the MMR vaccine. Given the evidence currently available, further research on BMI and vaccines in general remains desirable.

Shifts in the bacterial community of saliva give insights on the relationship between obesity and oral microbiota in adolescents

The current study aimed at the determination of the impact of obesity on the salivary microbiome in adolescents. Sixty subjects ranging 14-17 years old were enrolled (obese: n = 30-50% females, and normal weight: n = 30-50% females). Stimulated saliva was collected for denaturing gradient gel electrophoresis (DGGE) band patterns and massive 16S rRNA gene sequencing using the Ion Torrent platform. Overall, data analysis revealed that male subjects harbored a higher diverse salivary microbiome, defined by a significant higher richness (32.48 versus 26.74) and diversity (3.36 versus 3.20), higher Simpson values (0.96 versus 0.95) and distinct bacterial community structure considering either sex or condition (p < 0.05). Bacterial community fingerprinting analysis in human saliva showed a positive correlation with increased body mass index (BMI) in adolescents. Veillonella, Haemophilus and Prevotella occurrence was found to be affected by BMI, whereas Neisseria and Rothia occurrence was significantly impacted by sex in obese subjects. Our findings suggest that male and female adolescents may harbor a naturally distinct salivary microbiota and that obesity may specifically have an impact on their oral bacterial community. The potential dysbiotic oral microbiome in obese adolescents raises new insights on the etiology and prevention of future conditions in these populations.

Twenty-five years of research about adipogenic adenoviruses: A systematic review

Infectious etiology is implicated in chronic diseases such as gastric ulcer or atherosclerosis. However, "infection" is a recent term in the field of obesity. Since the first report in 1982 of obesity due to infection, several microbes have been linked to obesity. Among the adipogenic microbes, avian adenovirus SMAM-1 and human adenovirus Ad36 have been studied most extensively for the past 25 years. Here, we present a systematic review of literature about SMAM-1 and Ad36. Reports from North America, Europe, and Asia reveal strong evidence that Ad36 causes obesity in animals and paradoxically improves glycemic control, and in vitro data provides mechanistic explanation. Considering that experimental Ad36 infection of humans is unlikely, its causative role in human obesity or glycemic control has not been demonstrated unequivocally. Nonetheless, most, but not all, observational studies in children and adults link Ad36 infection to obesity and improvement in glycemic control. The E4orf1 gene of Ad36 was identified as responsible for better glycemic control. Overall, 25 years have considerably advanced knowledge about the role of infection in obesity. Potential translational benefits include the development of vaccines to prevent Ad36-induced obesity and drug development based on the E4orf1 protein to improve glycemic control.

Antibiotic treatment of rat dams affects bacterial colonization and causes decreased weight gain in pups

Intergenerational transmission of bacteria during birth initiates the natural successional development of the intestinal microbiota in mammals. This process can be disrupted by antibiotic exposure, potentially affecting early-life microbiota-dependent metabolic programming. In the present study, we specifically investigate the metabolic consequences of exposing neonate Wistar rats to an antibiotic-perturbed low-diversity microbiota from birth until weaning, without exposing the pups directly to antibiotics. Here, we show that pups born from both amoxicillin and vancomycin-treated dams gain less weight than controls. This was concordant with lower feed intake as well as increased colonic expression of the PYY satiety hormone gene at weaning. The weight difference persists into adulthood even though the initial differences in gut microbiota subsided. Our results demonstrate that early-life exposure to an antibiotic-perturbed low-diversity microbiota is sufficient to cause changes in body weight persisting into adulthood.

Effect of antibiotics on gut microbiota, glucose metabolism and body weight regulation: a review of the literature

Gut bacteria are involved in a number of host metabolic processes and have been implicated in the development of obesity and type 2 diabetes in humans. The use of antibiotics changes the composition of the gut microbiota and there is accumulating evidence from observational studies for an association between exposure to antibiotics and development of obesity and type 2 diabetes. In the present paper, we review human studies examining the effects of antibiotics on body weight regulation and glucose metabolism and discuss whether the observed findings may relate to alterations in the composition and function of the gut microbiota.

The development and validation of a meta-tool for quality appraisal of public health evidence: Meta Quality Appraisal Tool (MetaQAT)

OBJECTIVES

Most quality appraisal tools were developed for clinical medicine and tend to be study-specific with a strong emphasis on risk of bias. In order to be more relevant to public health, an appropriate quality appraisal tool needs to be less reliant on the evidence hierarchy and consider practice applicability. Given the broad range of study designs used in public health, the objective of this study was to develop and validate a meta-tool that combines public health-focused principles of appraisal coupled with a set of design-specific companion tools.

STUDY DESIGN

Several design methods were used to develop and validate the tool including literature review, synthesis, and validation with a reference standard.

METHODS

A search of critical appraisal tools relevant to public health was conducted; core concepts were collated. The resulting framework was piloted during three feedback sessions with public health practitioners. Following subsequent revisions, the final meta-tool, the Meta Quality Appraisal Tool (MetaQAT), was then validated through a content analysis of appraisals conducted by two groups of experienced public health researchers (MetaQAT vs generic appraisal form).

RESULTS

The MetaQAT framework consists of four domains: relevancy, reliability, validity, and applicability. In addition, a companion tool was assembled from existing critical appraisal tools to provide study design-specific guidance on validity appraisal. Content analysis showed similar methodological and generalizability concerns were raised by both groups; however, the MetaQAT appraisers commented more extensively on applicability to public health practice.

CONCLUSIONS

Critical appraisal tools designed for clinical medicine have limitations for use in the context of public health. The meta-tool structure of the MetaQAT allows for rigorous appraisal, while allowing users to simultaneously appraise the multitude of study designs relevant to public health research and assess non-standard domains, such as applicability.

Interaction of obesity and infections

There is evidence that certain infections may induce obesity. Obese persons may also have more severe infections and have compromised response to therapies. The objective of this study is to review the available literature identifying infections that potentially contribute to greater body mass index (BMI) and differential responses of overweight and obese persons to infections. A systematic literature review of human studies examining associations between infections and weight gain, differential susceptibility, severity, and response to prevention and treatment of infection according to BMI status (January 1980-July 2014) was conducted. Three hundred and forty-three studies were eligible for inclusion. Evidence indicated that viral infection by human adenovirus Ad36 and antibiotic eradication of Helicobacter pylori were followed by weight gain. People who were overweight or obese had higher susceptibility to developing post-surgical infections, H1N1 influenza and periodontal disease. More severe infections tended to be present in people with a larger BMI. People with a higher BMI had a reduced response to vaccinations and antimicrobial drugs. Higher doses of antibiotics were more effective in obese patients. Infections may influence BMI, and BMI status may influence response to certain infections, as well as to preventive and treatment measures. These observations have potential clinical implications.

Infection-Related Hospitalization in Childhood and Adult Metabolic Outcomes

BACKGROUND AND OBJECTIVES

Identifying childhood determinants of adult cardiometabolic disease would facilitate early-life interventions. There are few longitudinal data on the contribution of childhood infections. Therefore, we investigated whether hospitalization with childhood infection is associated with adult anthropometric and metabolic outcomes in a large, well-phenotyped longitudinal cohort.

METHODS

A total of 1376 subjects from the Cardiovascular Risk in Young Finns Study, aged 3 to 9 years at baseline (1980), who had lifetime data from birth onward on infection-related hospitalization (IRH) had repeated assessments through childhood and adolescence and at least once in adulthood (age 30-45 years in 2001-2011). Early childhood (<5 years), childhood/adolescence (5-18 years), adult (>18 years), and total lifetime IRHs were related to adiposity, BMI, and metabolic syndrome in adulthood. Analyses were adjusted for childhood and adulthood risk factors and potential confounders.

RESULTS

Early-childhood IRH correlated with adverse adult but not childhood metabolic variables: increased BMI (P = .02) and metabolic syndrome (risk ratio: 1.56; 95% confidence interval: 1.03-2.35; P = .03), adjusted for age, gender, birth weight, childhood BMI and other risk factors, and family income. The age at which differences in adult BMI became persistent was related to age of IRH in childhood. The greatest increase in adult BMI occurred in those with >1 childhood IRH.

CONCLUSIONS

Childhood IRH was independently associated with adverse adult metabolic variables. This finding suggests that infections and/or their treatment in childhood may contribute to causal pathways leading to adult cardiometabolic diseases.

Prenatal exposure to systemic antibacterials and overweight and obesity in Danish schoolchildren: a prevalence study

BACKGROUND/OBJECTIVE

Prenatal exposure to antibacterials may permanently dysregulate fetal metabolic patterns via epigenetic pathways or by altering maternal microbiota. We examined the association of prenatal exposure to systemic antibacterials with overweight and obesity in schoolchildren.

SUBJECTS/METHODS

We conducted a prevalence study among Danish schoolchildren aged 7-16 years using data from routine school anthropometric evaluations conducted during 2002-2013. Prenatal exposure to antibacterials was ascertained by using maternal prescription dispensations and infection-related hospital admissions during pregnancy. We defined overweight and obesity among the children using standard age- and sex-specific cutoffs. We computed sex-specific adjusted prevalence ratios (aPRs) of overweight and obesity associated with exposure to prenatal antibacterials, adjusting for maternal age at delivery, marital status, smoking in pregnancy and multiple gestation; we also stratified the analyses by birth weight.

RESULTS

Among 9886 schoolchildren, 3280 (33%) had prenatal exposure to antibacterials. aPRs associated with the exposure were 1.26 (95% confidence interval (CI): 1.10-1.45) for overweight and 1.29 (95% CI: 1.03-1.62) for obesity. Among girls, aPRs were 1.16 (95% CI: 0.95-1.42) for overweight and 1.27 (95% CI: 0.89 to 1.82) for obesity. Among boys, aPRs were 1.37 (95% CI: 1.13-1.66) for overweight and 1.29 (95% CI: 0.96-1.73) for obesity. The aPR for overweight was higher among schoolchildren with birth weight <3500 g (aPR: 1.30, 95% CI: 1.05-1.61) than in schoolchildren with birth weight ⩾3500 g (aPR: 1.18, 95% CI: 0.95-1.46). Inversely, the association for obesity was higher among schoolchildren with birth weight ⩾3500 g (aPR: 1.35, 95% CI: 1.00-1.81) than among those who were <3500 g at birth (aPR: 1.16, 95% CI: 0.82-1.65).

CONCLUSIONS

Prenatal exposure to systemic antibacterials is associated with an increased risk of overweight and obesity at school age, and this association varies by birth weight.

Long-term pathological consequences of prenatal infection: beyond brain disorders

Prenatal immunological adversities such as maternal infection have been widely acknowledged to contribute to an increased risk of neurodevelopmental brain disorders. In recent years, epidemiological and experimental evidence has accumulated to suggest that prenatal exposure to immune challenges can also negatively affect various physiological and metabolic functions beyond those typically associated with primary defects in CNS development. These peripheral changes include excessive accumulation of adipose tissue and increased body weight, impaired glycemic regulation and insulin resistance, altered myeloid lineage development, increased gut permeability, hyperpurinergia, and changes in microbiota composition. Experimental work in animal models further suggests that at least some of these peripheral abnormalities could directly contribute to CNS dysfunctions, so that normalization of peripheral pathologies could lead to an amelioration of behavioral deficits. Hence, seemingly unrelated central and peripheral effects of prenatal infection could represent interrelated pathological entities that emerge in response to a common developmental stressor. Targeting peripheral abnormalities may thus represent a valuable strategy to improve the wide spectrum of behavioral abnormalities that can emerge in subjects with prenatal infection histories.