Bronchiolitis in young infants: is it a risk factor for recurrent wheezing in childhood?

Risk factors for recurrent wheezing after bronchiolitis

BACKGROUND

This study aimed to determine whether there was an association between certain factors in patients with bronchiolitis and recurrent wheezing in childhood.

METHOD

In 2021 we tracked children hospitalized for bronchiolitis at Chengdu Women's and Children's Central Hospital in 2017. The patients were classified into recurrent wheezing group (RWG) and non-recurrent wheezing group (NRWG). Possible risk factors including maternal age, school-age siblings, allergic history, atopic dermatitis, allergic rhinitis, atopic family history, severity of the condition, duration of hospitalization, nasopharyngeal secretions culture, blood eosinophil counts, FeNO and skin prick test were compared between the two groups. Continuous variables were analyzed by independent sample t-test for normal distribution and Mann-Whitney U-test for non-normal distribution. Categorical variables were tested using chi-square tests. Multifactor analysis was conducted by stepwise logistics regression analysis.

RESULTS

In total 167 participants were included, of which 26 and 141 were in RWG and NRWG respectively. In RWG children represented higher maternal age (P = 0.02) and greater probability of allergic history, atopic dermatitis, allergic rhinitis, atopic family history (odds ratio [OR] = 4.0,3.7, 7.8, 10.9 respectively, P < 0.01). However, school-age siblings, severity of the condition, duration of hospitalization, blood eosinophil counts, fractional exhaled nitric oxide and skin prick test results seemed unrelated to recurrent wheezing. In the subgroup analysis of nasopharyngeal secretion culture, there were more Moraxella catarrhalis-positive in RWG(P = 0.043). Atopic dermatitis, allergic rhinitis and atopic family history were identified as independent risk factors for recurrent wheezing.

CONCLUSION

Some children with bronchiolitis will develop recurrent wheezing, and the risk factors are allergic history, Moraxella catarrhalis infection or colonization, atopic dermatitis, allergic rhinitis and atopic family history; the latter three are independent risk factors.

Risk Factors Affecting Development and Persistence of Preschool Wheezing: Consensus Document of the Emilia-Romagna Asthma (ERA) Study Group

Wheezing at preschool age (i.e., before the age of six) is common, occurring in about 30% of children before the age of three. In terms of health care burden, preschool children with wheeze show double the rate of access to the emergency department and five times the rate of hospital admissions compared with school-age asthmatics. The consensus document aims to analyse the underlying mechanisms involved in the pathogenesis of preschool wheezing and define the risk factors (i.e., allergy, atopy, infection, bronchiolitis, genetics, indoor and outdoor pollution, tobacco smoke exposure, obesity, prematurity) and the protective factors (i.e., probiotics, breastfeeding, vitamin D, influenza vaccination, non-specific immunomodulators) associated with the development of the disease in the young child. A multidisciplinary panel of experts from the Emilia-Romagna Region, Italy, addressed twelve key questions regarding managing preschool wheezing. Clinical questions have been formulated by the expert panel using the PICO format (Patients, Intervention, Comparison, Outcomes). Systematic reviews have been conducted on PubMed to answer these specific questions and formulate recommendations. The GRADE approach has been used for each selected paper to assess the quality of the evidence and the degree of recommendations. Based on a panel of experts and extensive updated literature, this consensus document provides insight into the pathogenesis, risk and protective factors associated with the development and persistence of preschool wheezing. Undoubtedly, more research is needed to improve our understanding of the disease and confirm the associations between certain factors and the risk of wheezing in early life. In addition, preventive strategies must be promoted to avoid children's exposure to risk factors that may permanently affect respiratory health.

Prevalence and associated factors of wheeze in early infancy

BACKGROUND

The aim of this study was to assess the prevalence of wheeze in early childhood and to characterize associated factors for wheeze that could identify potentially feasible interventions for the future prevention of wheeze.

METHODS

We performed a cross-sectional analysis of the data from the International Study of Asthma and Allergies in Childhood (ISAAC)-modified self-administered questionnaire of parents of 4-month-old infants at well-child visits (mandatory health check-ups) in Nagoya City, Japan, between April 2016 and March 2017 (development dataset) and between April 2017 and March 2018 (validation dataset). We used a multivariable, multilevel analysis to identify significant (P < 0.05), associated factors (Bonferroni correction was applied as necessary) after adjustment for local outbreaks of virus-transmitted diseases, access to medical facilities, and socioeconomic status.

RESULTS

Among the 20 362 questionnaires given to families of infants living in Nagoya City (development dataset), 19 104 questionnaires (93.8%) were analyzed after data cleaning. In all, 1,446 (7.6%) infants experienced wheeze at least once within 4 months of age, 991 (5.2%) visited the clinic/hospital with wheeze, and 244 (1.3%) underwent hospitalization at that time. In the multilevel, multivariable model for hospitalization with wheeze, significant associated factors were male sex (adjusted odds ratio 1.8; 95% confidence interval 1.4-2.3), maternal current smoking (3.3; 2.0-5.5), and having at least one sibling (3.0; 2.2-4.1). These factors were also associated with wheeze and clinic/hospital visit with wheeze, and the results were confirmed in the validation dataset.

CONCLUSIONS

Our study highlights that smoking cessation among mothers and improved hand hygiene at home are two interventions that could potentially decrease wheeze in early infancy.

Risk factors for recurrent wheezing after bronchiolitis in infants: 2-year follow up in China

Background

Infants with bronchiolitis have an increased risk of developing recurrent wheezing and asthma. However, the risk factors for the development of recurrent wheezing after bronchiolitis remains controversial. Our study was to investigate risk factors of post-bronchiolitis recurrent wheezing.

Methods

Infants with bronchiolitis were enrolled from November 2016 through March 2017. Nasopharyngeal aspirates were obtained for detection of respiratory viruses which were analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and direct immunofluorescent assay. Serum cytokines including TSLP, IL2, IL13, TIMP-1, MMP-9, IL33, IL5, IL4, IL25, TNF- α and MIP-1α were measured by flow cytometry. Patients were followed up every 3 months for a duration of 2 years by telephone or at outpatient appointments.

Results

We enrolled 89 infants, of which 81 patients were successfully followed up. In total, 22.2% of patients experienced recurrent wheezing episodes. The proportion of patients with history of eczema, systemic glucocorticoid use and patients with moderate-to-severe disease were significantly higher in the recurrent wheezing group than the non-recurrent wheezing group (83.3% vs 52.4%; 66.7% vs 36.5%; 61.1% vs 33.3%, respectively, all P < 0.05); There were no significant differences between patients with and without recurrent wheezing episodes in the levels of TSLP, IL2, IL13, TIMP-1, MMP-9, IL33, IL5, IL4, IL25, TNF- α and MIP-1α (P > 0.05). Logistic regression analysis showed that history of eczema was an independent risk factor for post-bronchiolitis recurrent wheezing (odds ratio [OR] = 5.622; 95% confidence interval [CI], 1.3–24.9; P = 0.023).

Conclusion

The incidence of recurrent wheezing among infants after contracting bronchiolitis was 22.2% during a 2-year follow-up. History of eczema was the only independent risk factor identified and no correlation was found between the specific virus and disease severity in children with post-bronchiolitis recurrent wheezing.

Recurrent wheezing after bronchiolitis caused by respiratory syncytial virus in children younger than 3 years: A 1-year follow-up study

We analysis the frequency and risk factors of wheezing in infants. We chose children with initial wheezing before 3 years of age who were hospitalized for medical treatment. Wheezing frequency was determined by follow-up at 1 week, 1 month, 3 months, 6 months, and 1 year. Information such as birth status, age, sex, preterm, mode of delivery, birth order, eczema history, personal allergy history, family allergy history, passive smoking, and place of residence (urban/rural) was collected. Total serum IgE level, serum allergen testing, routine blood tests, C-reactive protein level, procalcitonin level, respiratory pathogens tests, sputum culture, chest radiography or computed tomography were performed in all patients. The correlation between each factor and wheezing recurrence was evaluated. A total of 259 children were included in the study. They were divided into single recurrence, multiple recurrences, and no recurrence groups. The recurrence rate of wheezing was 56.8% (30.5% had a single recurrence and 26.3% had 2 or more recurrences). The percentage of children with a personal allergy history in the multiple recurrences group was significantly higher than in the single recurrence and no recurrence groups ( P = 0.031 and 0.008, respectively). The age of the children in the multiple recurrences group was significantly lower than that in the single recurrence group ( P < 0.001). Clinical severity scores were higher in the multiple recurrences group than in the single recurrence and no recurrence groups ( P = 0.002 and <0.001, respectively). Most children did not experience multiple recurrent wheezing. Children with young age, serious condition, and allergic constitution were prone to recurrent wheezing.

Does respiratory syncytial virus lower respiratory illness in early life cause recurrent wheeze of early childhood and asthma? Critical review of the evidence and guidance for future studies from a World Health Organization-sponsored meeting

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection (LRTI) and hospitalization in infants and children globally. Many observational studies have found an association between RSV LRTI in early life and subsequent respiratory morbidity, including recurrent wheeze of early childhood (RWEC) and asthma. Conversely, two randomized placebo-controlled trials of efficacious anti-RSV monoclonal antibodies (mAbs) in heterogenous infant populations found no difference in physician-diagnosed RWEC or asthma by treatment group. If a causal association exists and RSV vaccines and mAbs can prevent a substantial fraction of RWEC/asthma, the full public health value of these interventions would markedly increase. The primary alternative interpretation of the observational data is that RSV LRTI in early life is a marker of an underlying predisposition for the development of RWEC and asthma. If this is the case, RSV vaccines and mAbs would not necessarily be expected to impact these outcomes. To evaluate whether the available evidence supports a causal association between RSV LRTI and RWEC/asthma and to provide guidance for future studies, the World Health Organization convened a meeting of subject matter experts on February 12-13, 2019 in Geneva, Switzerland. After discussing relevant background information and reviewing the current epidemiologic evidence, the group determined that: (i) the evidence is inconclusive in establishing a causal association between RSV LRTI and RWEC/asthma, (ii) the evidence does not establish that RSV mAbs (and, by extension, future vaccines) will have a substantial effect on these outcomes and (iii) regardless of the association with long-term childhood respiratory morbidity, severe acute RSV disease in young children poses a substantial public health burden and should continue to be the primary consideration for policy-setting bodies deliberating on RSV vaccine and mAb recommendations. Nonetheless, the group recognized the public health importance of resolving this question and suggested good practice guidelines for future studies.