Risk factors for recurrent wheezing in infants: a case-control study

An analysis of risk factors associated with recurrent wheezing in the pediatric population

BACKGROUND

Recurrent wheezing is a common clinical problem in early childhood, which is associated with significant morbidity. There is no international consensus on the management and prevention of recurrent wheezing; therefore, identifying the risk factors associated with recurrent wheezing is crucial to prevent episodes of wheezing in young children.

METHODS

In this retrospective study, we collected the data of 24,737 patients who were admitted to our hospital between 27th April 2012 and 11th September 2019. After screening for patients with wheezing, we identified 8572 patients with a primary diagnosis of pneumonia with wheezing. Patients' clinical data were collected from the hospital medical records. Patients were stratified for age in the groups of < 6 months, 6-12 months, and > 12 months.

RESULTS

Among the 8569 pediatric pneumonia patients with wheezing, there were 343 patients with recurrent wheezing. Most enrolled patients were under 6 months of age (45.17%) and had a normal birth weight (86.95%). Winter was the most common onset season for the first episode of wheezing, while spring was the most common season for the second episode of wheezing for those with recurrent wheezing. The univariate and multivariate logistic regression analysis for the risk factor associated with recurrent wheezing showed that male gender, past history of respiratory and cardiovascular diseases, low birth weight, development of severe pneumonia, and PICU admission were significantly associated with recurrent wheezing.

CONCLUSION

Male gender, past history of respiratory and cardiovascular diseases, low birth weight, severe pneumonia, and PICU admission are independent risk factors of recurrent wheezing in the pediatric population.

Children at the Risk of Recurrent Wheezing: A Matched Case-Control Study in a Tertiary Care Center

Introduction Wheezing is a common symptom in early childhood. Recurrent wheezing is defined as more than three episodes of wheezing in the past year. Many studies have been conducted to delineate the risk factors for recurrent wheezing and to predict which of these children will progress to asthma. Most studies about risk factors and the clinicodemographic profile of children with recurrent wheeze have been carried out in developed nations. Data in developing countries may differ. This study was carried out to identify risk factors associated with recurrent wheezing in children in a tertiary care center. Materials and methods It was a retrospective, matched case-control study conducted over a period of two years (July 2019 to July 2021). Records of children aged one month to 12 years who came to pediatric OPD or were admitted to a pediatric ward with a history of recurrent wheezing were included in the study. Cases with uncontrolled recurrent wheezing diagnosed by examination with an unreliable history and those with a global developmental delay were excluded from the study. The study involved the hospital records of 60 children. Of these, 30 were recurrent wheezers, and 30 were non-wheezers (controls). Data were collected with detailed proformas from case histories and examination sheets. The proforma had several known and suspected risk factors associated with wheezes. Each risk factor was studied and compared with the control group. The risk factors included in this study were male gender, not exclusively breastfed, history of bottle feeding, exposure to vehicles; exposure to pollen; exposure to animals; using an agarbatti or dhoop, passive smoking, or playing with a soft toy. Data were entered in an Excel sheet, and appropriate statistical analyses were done. Results The male-to-female ratio was 2:1. Out of the number of cases, 73.33% were younger than six years; 56.66% of cases were not exclusively breastfed, and 43.33% were exclusively breastfed for six months; 20% of the cases were bottle-fed, and 40% of the controls were bottle-fed. The percentage of cases exposed to vehicle smoke was 26.66%, while 20% of cases had exposure to pollen and 16% of controls were exposed to pollen. 30% of cases were exposed to animals, and 23% of controls were exposed to animals. With regard to passive smoking, 16.66% of cases were exposed to passive smoking, and 20% of controls were not exposed to passive smoking. Out of the study group, 26.66% of the children played with soft toys. Of all these risk factors, a significant difference between cases and controls was found in only one factor: not being exclusively breastfed for six months. All other risk factors showed no significant difference between cases and controls. Conclusion The present study concluded that the significant risk factor that was associated with recurrent wheezing was "not exclusively breastfeeding." The other factors studied that were suspected to be associated with recurrent wheezing cannot be ruled out entirely due to the relatively small size of the sample and the need to be studied further in detail.

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.

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.

Prevalence of vitamin D deficiency and its relationship with factors associated with recurrent wheezing

Objective:

To determine the prevalence of vitamin D deficiency/insufficiency in children 0-18 years of age with recurrent wheezing and/or asthma residing in the microregion of Viçosa, Minas Gerais, Brazil, and treated at a referral center, and to determine its association with major risk factors for wheezing.

Methods:

A cross-sectional study was performed using a semi-structured questionnaire, which was administered by trained interviewers to the legal guardians of the study participants. Data were obtained regarding general characteristics of recurrent wheezing; general sociodemographic, environmental, and biologic factors; and atopy-related factors. The magnitude of the statistical association was assessed by calculating ORs and their corresponding 95% CIs by using multiple logistic regression.

Results:

We included 124 children in the study. The prevalence of vitamin D deficiency/insufficiency in the sample was 57.3%. Vitamin D deficiency/insufficiency was found to be associated with wheezing in the first year of life, personal history of atopic dermatitis, environmental pollution, and vitamin D supplementation until 2 years of age.

Conclusions:

The prevalence of vitamin D deficiency/insufficiency was high in our sample. Vitamin D concentrations were directly associated with vitamin D supplementation until 2 years of age and were inversely associated with wheezing events in the first year of life, personal history of atopic dermatitis, and environmental pollution.

Predicting Asthma Using Clinical Indexes

Asthma is no longer considered a single disease, but a common label for a set of heterogeneous conditions with shared clinical symptoms but associated with different cellular and molecular mechanisms. Several wheezing phenotypes coexist at preschool age but not all preschoolers with recurrent wheezing develop asthma at school-age; and since at the present no accurate single screening test using genetic or biochemical markers has been developed to determine which preschooler with recurrent wheezing will have asthma at school age, the asthma diagnosis still needs to be based on clinical predicted models or scores. The purpose of this review is to summarize the existing and most frequently used asthma predicting models, to discuss their advantages/disadvantages, and their accomplishment on all the necessary consecutive steps for any predictive model. Seven most popular asthma predictive models were reviewed (original API, Isle of Wight, PIAMA, modified API, ucAPI, APT Leicestersher, and ademAPI). Among these, the original API has a good positive LR~7.4 (increases the probability of a prediction of asthma by 2-7 times), and it is also simple: it only requires four clinical parameters and a peripheral blood sample for eosinophil count. It is thus an easy model to use in any rural or urban health care system. However, because its negative LR is not good, it cannot be used to rule out the development of asthma.

Improving the global diagnosis and management of asthma in children

Asthma is the most common chronic condition in children worldwide. It affects daytime activities, sleep and school attendance and causes anxiety to parents, families and other carers. The quality of asthma diagnosis and management globally still needs substantial improvement. From infancy to the teenage years, there are age-specific challenges, including both underdiagnosis and overdiagnosis with stigma-related barriers to treatment in some cultures and in adolescents. Guidelines are increasingly evidence based, but their impact on improving outcomes has been negligible in many parts of the world, often due to lack of implementation. New thinking is needed to enable substantial improvements in outcomes. The disease varies globally and plans will need to differ for individual countries or places where region-specific barriers prevent optimal care. A wide selection of educational activities is needed, including community-targeted initiatives, to engage with families. The Paediatric Asthma Project Plan has been initiated to strengthen diagnosis and management of asthma. This encompasses a vision for the next 10–15 years, building on the knowledge and experience from previous educational projects. It will take into account the educational needs of patients, carers and healthcare professionals as well as the accessibility and affordability of medication, particularly in low and middle-income countries where the prevalence of asthma is rising more rapidly. This overview presents a first step for those involved in the diagnosis and management of childhood asthma to strengthen care for children globally.

Wheezing in Infancy: An Overview of Recent Literature

PURPOSE OF REVIEW

Wheezing in infancy is a common presentation with many potential causes. In writing this review, we sought to summarize the newest recommendations and testing available for the more common etiologies of wheezing.

RECENT FINDINGS

Regarding the diagnosis of asthma, the modified asthma predictive index has recently been established as a useful predictive tool. Non-breath held multidetector CT with 3D volume rendering airway images is also a newer helpful diagnostic tool for tracheomalacia due to ease of use and its 100% positive predictive value. We found vaccines have greatly reduced the prevalence of epiglottitis, while advances in surgery are improving outcomes in infants with vascular rings. Wheezing in infants is a common problem with an extensive differential diagnosis from relatively benign to life threatening. To prevent over-looking a diagnosis that potentially requires surgical correction or emergent care, we recommend a structured approach to the history and physical exam with targeted testing directed towards the most likely diagnoses as outlined in this review.