Changes in the prevalence and severity of recurrent wheezing in infants: The results of two surveys administered 7 years apart

The wheezy infant: A viewpoint from low-middle income countries

OBJECTIVE

To review the recent evidence in the literature of various aspects of recurrent/severe wheezing in children under 3 in low-middle income countries [LMICS].

SOURCES

A non-systematic review including articles in English. We mainly selected publications from the last 5 years. Studies on epidemiology, aetiology, diagnosis, treatment, and prevention were included in the search. We reviewed differential diagnoses of wheezing that focused on LMICS. We also reviewed aspects of prevention.

SUMMARY OF THE FINDINGS

Many epidemiological studies have shown a variable but significant number of wheezy infants [WI] cases in LMICS when compared to other countries. The differential diagnosis of causes of wheezing in this age group is mandatory, taking into account local facilities. Few treatment options have been well studied for this age group. In LMICS, a pragmatic approach could be considered, as described in the article. It is difficult to study primary prevention for WI and secondary prevention (mainly environmental) may have some impact. A schematic approach for recurrent wheezers is presented, which takes into account settings with limited resources.

CONCLUSION

Severely or recurrently wheezy children under 3 is a common clinical issue in LMICS. Studies on this age group are needed to reduce the significant morbidity. It may be possible to lower the high burden of wheezing in this age group by selecting the phenotype which may respond to inhaled steroids.

Risk Factors Associated With Health Care Utilization in Preschool Recurrent Wheezers in a Tropical Environment

Introduction: The severity of wheezing episodes is related with the need for health services, but the factors associated with health care utilization in preschool recurrent wheezers in underdeveloped regions are unclear. Objective: To evaluate the factors associated with health care utilization in preschool recurrent wheezers in Cartagena, Colombia. Methods: One hundred twenty-seven recurrent wheezers (age 2-6 years old) who were admitted to the emergency room (ER) due to wheezing in a Pediatric reference hospital in Cartagena were included. Children were evaluated by means of questionnaires and classified according to the number of ER visits, need for hospitalization and history of intensive care unit (ICU) admission due to wheezing within the last year. Total serum IgE and specific IgE to house dust mite allergens (HDM) were measured by ImmunoCAP® and allergen sensitization was evaluated by skin prick tests (SPT). Results: The maternal report of nocturnal cough without fever in their children increased the risk to have ≥5 ER visits in the last year due to wheezing. The use of montelukast was negatively associated with hospitalization, while a history of pneumonia and lack of tap water, increased the risk of hospitalization due to wheezing. A history of bronchiolitis, family history of asthma, cohabiting with two or more siblings, passive exposure to smoke and lack of sewage facilities increased the risk of ICU admission due to wheezing. The presence of atopy evaluated by SPT reactivity, total IgE levels or specific IgE to HDM were not associated with health care utilization. We also found that seroprevalence of positive IgE (≥0.35 kU/L) was 27% to B. tropicalis and 20.3% to D. pteronyssinus but the prevalence of positive IgE sensitization to these allergens was below 2% and 8% when evaluated by SPT, respectively. Conclusions: Poverty indicators are associated with ICU admission in a group of preschool recurrent wheezers and should be considered as aggravating factors for wheezing. These factors must be systematically assessed in the medical approach in underdeveloped regions in the tropics. Nocturnal cough without fever is a symptom associated with frequent ER visits while atopy was not associated with health care utilization in preschool recurrent wheezers.

Prevalence and Determinants of Tobacco Smoking Among Low-Income Urban Adolescents

Background: Tobacco-smoking in children is one of the most crucial public health concerns, which could be highly prevalent in underprivileged populations. Methods: A cross sectional, random sampling survey was conducted to determine the prevalence of current tobacco-smoking and related risk factors among adolescents living in a low-income area of Santiago de Chile. Results: Of the 2,747 adolescents participating in the study, 24.0% [95% confidence interval (CI) 22.3-25.5] were current smokers, with no significant difference between girls and boys. Factors associated with current smoking were as follows: positive attitude to smoking cigarettes offered by peers [odds ratio (OR) 8.0; 95% CI 5.7-11.3, P < 0.001], having smoking best friends (OR 4.0; 95% CI 2.6-6.0, P < 0.001), and passive smoking in the house (OR 1.9; 95% CI 1.2-3.1, P = 0.008). A total of 16.8% (95% CI 11.4-18.2) of children had smoked an entire cigarette at the age of ≤12, and 62.3% (95% CI, 60.5-64.1) were passive smokers at home. Regarding nonsmoking children, 52.4% (95% CI 49.74-55.06) were exposed to tobacco smoke at home. Conclusion: The prevalence of current tobacco-smoking in adolescents is high and increasing compared to previous studies undertaken in the selected low-resourced area. Two-thirds of children who started smoking before the age of 12 years were current smokers at the time of the survey, highlighting the prevalence of the powerful addiction generated and the need for better preventive strategies against tobacco-smoking for children living in low-resource communities.

Trends in worldwide asthma prevalence

This review of trends in worldwide asthma prevalence starts with defining how asthma prevalence is measured in populations and how it is analysed. Four population studies of asthma across at least two regions are described: European Community Respiratory Health Survey (ECRHS), the International Study of Wheezing in Infants (EISL), the International Study of Asthma and Allergies in Childhood (ISAAC) and the World Health Survey (WHS). Two of these (ISAAC and WHS) covered all the regions of the world; each using its own standardised questionnaire-based methodology with cross-sectional study design, suitable for large populations. EISL (2005 and 2012) and ISAAC (1996-1997 and 2002-2003) have undertaken a second cross-sectional population survey from which trends are available: EISL in three centres in two countries; ISAAC 106 centres in 56 countries (13-14 year olds) and 66 centres in 37 countries (6-7 year olds). Key results from these studies are presented. Unfortunately, there is no new worldwide data outside of EISL since 2003. Global Burden of Disease estimates of asthma prevalence have varied greatly. Recent reliable worldwide data on asthma prevalence and trends is needed; the Global Asthma Network Phase I will provide this in 2021.

Prevalence of recurrent wheezing during the first year of life in Setúbal district, Portugal

BACKGROUND

Recurrent wheezing during the first year of life is a major cause of respiratory morbidity worldwide, yet there are no studies on its prevalence in Portugal.

OBJECTIVE

Determine the prevalence and severity of recurrent wheezing, treatments employed and other related aspects, in infants during their first year of life in Setúbal, Portugal.

METHODS

This is a cross-sectional study of a random sample of infants aged 12-15 months living in Setúbal district. It uses a validated questionnaire answered by parents/caregivers at local healthcare facilities where infants attend for growth/development monitoring and/or vaccine administration.

RESULTS

Among the 202 infants surveyed, 44.6% (95% CI 37.7-51.4) had at least one episode of wheezing; and 18.3% (95% CI 12.9-23.6) had recurrent wheezing. There was significant morbidity associated to recurrent wheezing in terms of severe episodes (17.3%-95% CI 12-22.5), visits to the emergency department (26.2%-95% CI 20.1-32.2) and hospital admissions (5.4%-95% CI 2.2-8.5); 10.4% (95% CI 6.1-14.6) used inhaled corticosteroids and 7.9% (95% CI 4.1-11.6) used a leukotriene receptor antagonist.

CONCLUSIONS

The prevalence of recurrent wheezing in infants during the first year of life is high and is associated with significant morbidity, presenting as a relevant public health problem. An important proportion of infants' progress with a more severe condition, resulting in high use of health resources (visits to emergency department and hospitalisations). The prevalence of recurrent wheezing in this district of Portugal stays between those related in other European and Latin American Centres, suggesting that maybe some of the well-known risk factors are shared with affluent countries.