Obesity as a risk factor for severe influenza infection in children and adolescents: a systematic review and meta-analysis

Abstract

Obesity has been recently identified as a predisposing factor for a worse prognosis in viral illnesses such as SARS-CoV-2; however, its role in children with influenza is not yet clarified. The current systematic review and meta-analysis aims to assess whether obesity is a risk factor for either hospitalization or a worse prognosis when hospitalized among children infected by influenza. We systematically searched the following databases using a structured algorithm: MEDLINE, Clinicaltrials. gov, and Cochrane Central Register of Controlled Trials (CENTRAL). Statistical meta-analysis was performed using the "meta" package in R software, and included studies were evaluated using the Newcastle-Ottawa scale. Among children with influenza, obesity increased the odds of hospitalization with a pooled OR of 1.89 (95% CI [1.23, 2.9], I 2 = 0, p = 0.003). When hospitalized, children with obesity were also more likely to have a worse outcome than their healthy-weight counterparts, with a pooled OR of 1.24 (95% Cl [1.02; 1.51], I 2 = 11, p = 0.03). In an effort to lower heterogeneity, a leave-one-out meta-analysis was conducted. Publication bias was assessed with the visual inspection of funnel plots and the trim-and-fill method. Certainty assessment was evaluated using the GRADE score.Conclusions: The findings of our meta-analysis suggest that obesity in children with influenza is associated with a worse prognosis, both hospitalization and ICU admission/death. What is Known:• Obesity has been identified as a risk factor for non-communicable as well as communicable diseases.• A previous meta-analysis failed to demonstrate a statistically significant association between obesity and influenza infection severity. What is New:• Children with high BMI and influenza infection are more likely to get hospitalized. • Pediatric inpatients with increased BMI and influenza infection may have a worse prognosis.

Increased innate immune responses in adolescents with obesity and its relation to subclinical cardiovascular measures: An exploratory study

“…These findings are in line with heightened pro-inflammatory innate and inflammatory responses reported from adults with obesity, 26 , 27 who have higher monocyte numbers, 26 , 27 changes in monocyte subsets and increased activation markers on flow cytometry. 28 , 29 The sub-optimal anti-viral response is in keeping with epidemiological data which show increased disease severity and worse outcomes with SARS-COV-2 30 and influenza 31 in this population. Here we also show that higher inflammation at baseline among those with obesity is associated with adverse cardiovascular measures at follow-up.…”

Evaluation of disease severity and prediction of severe cases in children hospitalized with influenza A (H1N1) infection during the post-COVID-19 era: a multicenter retrospective study

“…Furthermore, this study identified that age, BMI, fever duration, leucocyte count, lymphocyte proportion, proportion of CD3 + T cells, TNF-α, and IL-10 were independently associated with occurrence of severe cases in children hospitalized with H1N1 infection during the post-COVID-19 period. First, consistent with the prior knowledge [ 28 , 29 ], both younger and overweight children are more prone to develop severe form of influenza infection. Second, as we know, during viral invasion, the brain orchestrates evolutionary conserved physiological symptoms, aiming to clear the pathogens and promote the survival of host [ 30 ].…”

Regulatory T cells and bioenergetics of peripheral blood mononuclear cells linked to pediatric obesity

“…Children and adolescents with overweight and obesity and those with T2D are more prone to severe infections (eg, flu and COVID-19) [34] . Based on our findings that the bioenergetics and metabolism in immune cells in general (ie, PBMCs) and in CD4 T cells are related to excess weight, insulin resistance, and glucose tolerance, we speculate that impaired immunity in overweight/obese and T2D children may be related to metabolic adaptations to overnutrition and elevated blood glucose.…”