The prevalence of wheezing and its association with body mass index and abdominal obesity in children

Understanding and controlling asthma in Latin America: A review of recent research informed by the SCAALA programme

Asthma is an important health concern in Latin America (LA) where it is associated with variable prevalence and disease burden between countries. High prevalence and morbidity have been observed in some regions, particularly marginalized urban populations. Research over the past 10 years from LA has shown that childhood disease is primarily non-atopic. The attenuation of atopy may be explained by enhanced immune regulation induced by intense exposures to environmental factors such as childhood infections and poor environmental conditions of the urban poor. Non-atopic symptoms are associated with environmental and lifestyle factors including poor living conditions, respiratory infections, psychosocial stress, obesity, and a diet of highly processed foods. Ancestry (particularly African) and genetic factors increase asthma risk, and some of these factors may be specific to LA settings. Asthma in LA tends to be poorly controlled and depends on access to health care and medications. There is a need to improve management and access to medication through primary health care. Future research should consider the heterogeneity of asthma to identify relevant endotypes and underlying causes. The outcome of such research will need to focus on implementable strategies relevant to populations living in resource-poor settings where the disease burden is greatest.

Childhood overweight and obesity and abnormal birth anthropometric measures are associated with a higher prevalence of childhood asthma in pre-school age

OBJECTIVES

Childhood asthma is one of the most common non-communicable diseases in the world. Several perinatal and postnatal factors have been associated with increased risk of developing childhood asthma. The present study aims to assess whether childhood overweight and obesity and abnormal birth anthropometric measures affect the risk of developing childhood asthma in preschool age.

METHODS

In this study, 5215 preschool children at the age of 2-5 years were enrolled after applying several inclusion and exclusion criteria and they examined whether they present asthma symptoms. Non-adjusted and adjusted statistical analysis was performed to assess whether perinatal and postnatal factors increase the risk of developing childhood asthma.

RESULTS

A prevalence of 4.5% of childhood asthma was recorded. Among children diagnosed with asthma, 19.4% were affected by overweight and 13.9% were obese. Childhood overweight/obesity was indepedently associated with a 76% higher risk of childhood asthma than normal weight. Abnormal birth anthropometric measures, i.e. birth weight, length, and head circumference, were independently associated with higher odds (87%, 29%, and 23%, respectively) of childhood asthma than normal ranges.

CONCLUSIONS

This is a cross-sectional, nationally representative study which supported evidence that childhood overweight/obesity and abnormal birth anthropometric measures may independently increase the risk of childhood asthma in preschool age. Emergent health policies and strategies are recommended to promote a healthy lifestyle, preventing childhood obesity at the early stages of life.

Maternal and early childhood factors associated with asthma and obesity in children aged 6 to 7 years: a case control study

Objective

To determine the maternal and early childhood factors associated with asthma and obesity in children aged 6 to 7 years.

Methods

A case-control study conducted with children aged 6 to 7 years. Applications with questions about asthma symptoms in the last 12 months, maternal and childhood data in the first 2 years of life, and anthropometric data were collected. Children who presented asthma symptoms were considered as cases and those without asthma symptoms were considered as controls, later divided into two subgroups that were eutrophic or overweight/obesity. Logistic regression was performed to estimate the association between asthma symptoms (adequate weight and overweight/obesity) and gestational and personal factors, calculating odds ratio and 95% confidence interval (95%CI). Values of p<0.05 were considered significant.

Results

Two hundred and one children were evaluated, 25.4% had asthma symptoms, 37.2% of them were overweight/obesity. Waist circumference, triceps skinfold, and body mass index were higher in the group with overweight/obesity asthma symptoms compared to no asthma symptoms (p<0.05). Factors significantly associated with asthma and overweight/obesity symptoms included: the maternal history of asthma (odds ratio of 3.73; 95%CI: 1.10-12.6) and hypertension during pregnancy (odds ratio of 3.29; 95%CI: 1.08-9.94).

Conclusion

Maternal history of asthma and hypertension during pregnancy increased the chances of children, at 6 and 7 years of age, having symptoms of asthma and obesity.

ADIPOQ and LEP variants on asthma and atopy: Genetic association modified by overweight

BACKGROUND

Asthma and atopy are considered condition associated with obesity, being affected by genetic and environmental factors. The LEP and ADIPOQ genes, responsible for the expression and secretion of leptin and adiponectin, respectively, and polymorphisms in such genes have been linked to both diseases, independently, and also with the obesity-associated asthma phenotype in populations with high European ancestry and high-income countries. However, in mixed populations, there are few studies evaluating the impact of these variants in genes associated with the phenotype of asthma and obesity. Thus, the aim of this study was to investigate variants in LEP and ADIPOQ associated with asthma and atopy, and whether overweight modifies that effect.

METHODS

The study involved 203 asthmatics children and 813 control subjects (between 5 and 11 years old), with or without overweight, from the SCAALA (Asthma and Allergy Social Changes in Latin America) program. Among them, 831 had data for allergy markers, being 258 atopic and 573 non-atopic. Genotyping was performed using a commercial panel Omnium Illumina 2.5. Logistic regression was performed to identify associations expected by using PLINK 1.09 and three genetic models: additive, dominant and recessive adjusted for sex, age, helminth infection, BMI and Principal Components (PC) 1 and 2, for ancestry, in order to control the confounding factor by population structure.

RESULTS

For asthma, G allele of rs822396, in ADIPOQ, was positively associated in additive model (OR 1.4, 95% CI 1.08-1.83) and T allele of rs1063537 in dominant model (OR 1.52, 95% CI 1.01-2.30). In LEP, rs11763517 (C allele) and rs11760956 (A allele) were both negatively associated with asthma in the additive model (OR 0.70, 95% CI 0.54-0.91; OR 0.66, 95% CI 0.50-0.89) respectively, and the A allele of rs2167270 in dominant model (OR 0.71, 95% CI 0.51-0.98). The G allele of rs12706832 showed a positive association with asthma in the recessive model (OR 1.66, 95% CI 1.06-2.61). When the population was stratified by the BMI / Age Z-Score, the protection observed for asthma between the variants rs11760956, rs11763517 and rs2167270 was lost overweight individuals; The protection observed for atopy was lost in all variants (rs16861205, rs2167270 and rs17151919) in the overweight group.

CONCLUSION

These results suggest that SNPs on the LEP and ADIPOQ genes may have an impact on atopy and asthma. Furthermore, we also show that the asthma and atopy protection attributed to variants on LEP and ADIPOQ genes is lost in individuals exposed to overweight.

Prevalence and impact of asthma in schoolchildren in the city of Caxias do Sul-RS

OBJECTIVE

To analyze the prevalence and impact of asthma in schoolchildren from the city of Caxias do Sul, RS, Brazil.

METHODS

Cross-sectional observational and case-control study with children and adolescents between 7 and 15 years old, from public schools in Caxias do Sul, RS. The study is composed of two phases: Phase I analyzed the prevalence of asthma in the delimited population, investigating 1915 schoolchildren; Phase II quality of life questionnaires, asthma control and classification (for the asthmatic group), physical activity, school performance, pulmonary function tests and anthropometric measures were applied to 266 asthmatics and 288 controls.

RESULTS

The estimated prevalence of asthma was 16.1%. In the comparison between asthmatics and nonasthmatics premature birth (p<0.001) and diagnosis of another chronic disease at birth (p<0.001) were found. Regarding pulmonary function, significant differences were found in the values between groups in FEV₁, FEV₁/FVC and forced expiratory flow in the 25 and 75% (FEF_25-75%), being that asthmatics presented lower values. Among asthmatics, 133 (50.8%) did not have the disease controlled. In the anthropometric variables, significant differences were observed, with higher values in controls, in the the waist-to-height ratio (p=0.009) and in the perception of health (p<0.001). Quality of life is lower in asthmatics in the physical well-being domain (p=0.001) and in the total score (p=0.016). The total school performance score did not present a statistically significant difference between the groups.

CONCLUSION

The prevalence of asthma is similar to that of other industrialized urban centers and may negatively affect some areas of the development of schoolchildren.

Social, Environmental and Behavioral Determinants of Asthma Symptoms in Brazilian Middle School Students-A National School Health Survey (Pense 2012)

Biological and psychosocial factors are recognized contributors to the worldwide burden of asthma. However, the relationship between psychosocial factors and asthma symptoms among students in low- and middle-income countries remains underexplored. We aimed to identify socioeconomic, environmental, psychosocial, family-related and lifestyle factors associated with the self-reporting of asthma symptoms in Brazilian adolescents. This is a cross-sectional study using data from the 2012 PeNSE survey (n = 109,104). We analyzed the following variables: socioeconomic conditions, demographic characteristics, lifestyle, family context and dynamics, psychosocial indicators, smoking, and exposure to violence. Our outcome variable was the self-report of asthma symptoms in the past 12 months. The prevalence of wheezing was 22.7% (21.5–23.9). After adjusting for sex, age and the variables from higher hierarchical levels, exposure to violence (feeling unsafe at school, being frequently bullied, being exposed to fights with firearms) and physical aggression by an adult in the family were the environmental factors that showed the strongest associations with self-reporting of asthma symptoms. For psychosocial indicators of mental health and social integration, feelings of loneliness and sleeping problems were the strongest factors, and among individual behavioral factors, the largest associations were found for tobacco consumption. Our findings were consistent with previous studies, showing an association between self-reported asthma symptoms and socio-economic status, family context and dynamics, psychosocial indicators of mental health, exposure to violence and social integration, as well as a sedentary lifestyle and tobacco use.

Asthma trend in adolescence in Brazil: results of the National Adolescent School-based Health Survey (PeNSE 2012-2015)

OBJECTIVE

To compare the evolution of asthma indicators in the editions of the National School Health Survey (PeNSE 2012 and 2015).

METHODS

Cross-sectional study including Brazilian 9th grade students from public and private schools. Wheezing was assessed through the question: "In the past 12 months, did you have wheezing (or chirping) chest? (yes/no)", and to assess lifetime presence of asthma, the question was "Have you ever had asthma? (yes/no)".

RESULTS

Of the students, 23,52% reported wheezing or chirping chest in the past 12 months, with prevalences ranging from 16,80% (in Salvador, Bahia) to 27,43% (in Porto Alegre, Rio Grande do Sul). Lifetime presence of asthma was reported by 17,92% of the students, ranging from 13,98% (in Campo Grande, Mato Grosso do Sul) to 30,35% (in Porto Alegre, Rio Grande do Sul). There was also a decrease in the prevalence of self-report of wheezing/chirping chest in the last 12 months between the two editions of the survey (2012/2015) in 20 of the 27 Brazilian state capitals, especially in Belo Horizonte, Florianópolis, Cuiabá and Goiânia. However, prevalence of lifetime diagnostic of asthma increased from 2012 to 2015 in 26 of the 27 Brazilian state capitals.

CONCLUSION

There was a decrease in the prevalence of self-report of asthma symptoms and an increase of self-reported lifetime presence of asthma. Certainly, monitoring indicators of asthma prevalence is of high importance for health knowledge and the development of public policies.

Symptoms of asthma and associated factors in adolescents from Salvador, Bahia

OBJECTIVE

Identify the factors associated with asthma symptoms in adolescents.

METHODS

Cross-sectional study with the participation of 1,176 students between the ages of 11 and 17 years old, in Salvador, Bahia, Brazil. The asthma symptoms were identified by using the standardized questionnaire from The International Study of Asthma and Allergies in Childhood Program (ISAAC), phase III. The subjects' food intake data were collected by a semiquantitative food frequency questionnaire (FFQ) comprised of 97 food items. All of the information was collected during a single interview. Anthropometric, socioeconomic, and demographic data were collected from the study population. The robust Poisson model was adopted to obtain the raw and adjusted PR (prevalence ratio).

RESULTS

From the total number of adolescents, 57.6% are female and 83.71% of them were between 13 and 17 years old. The prevalence of asthma symptoms was of 7.6%, being higher among males (9.62%). The prevalence of wheezing in the last 12 months was 8.6%. Among the adolescents with rhinitis and eczema, the prevalence of asthma symptoms was of 15.2 and 14.3%, respectively. After an adjusted analysis, the following factors were identified: females PR = 0.64 (95%CI 0.42 - 0.96), rhinitis PR = 3.23 (95%CI 2.17 - 4.83) and the 2nd tertile of the healthy pattern (moderate consumption) PR = 0.61 (95%CI 0.37 - 0.99).

CONCLUSION

Rhinitis and eczema were presented as risk factors for asthma symptoms. The healthy food intake pattern that had been stratified in tertiles, presented the 2nd tertile as a protector for asthma symptoms.

Body Mass Index Development and Asthma Throughout Childhood

Several studies have found an association between overweight and asthma, yet the temporal relationship between their onsets remains unclear. We investigated the development of body mass index (BMI) from birth to adolescence among 2,818 children with and without asthma from a Swedish birth cohort study, the BAMSE (a Swedish acronym for “children, allergy, milieu, Stockholm, epidemiology”) Project, during 1994–2013. Measured weight and height were available at 13 time points throughout childhood. Asthma phenotypes (transient, persistent, and late-onset) were defined by timing of onset and remission. Quantile regression was used to analyze percentiles of BMI, and generalized estimating equations were used to analyze the association between asthma phenotypes and the risk of high BMI. Among females, BMI development differed between children with and without asthma, with the highest BMI being seen among females with persistent asthma. The difference existed throughout childhood but increased with age. For example, females with persistent asthma had 2.33 times’ (95% confidence interval: 1.21, 4.49) greater odds of having a BMI above the 85th percentile at age ≥15 years than females without asthma. Among males, no clear associations between asthma and BMI were observed. In this study, persistent asthma was associated with high BMI throughout childhood among females, whereas no consistent association was observed among males.

Let Them Breathe

Childhood asthma is caused by an interaction of genetic and modifiable environmental factors. Health inequities compound these environmental factors. As features of asthma are established during preschool years, these health inequities in urban children with asthma need to be addressed by preschool nurses.

Prevalence of asthma symptoms among adolescents in Brazil: National Adolescent School-based Health Survey (PeNSE 2012)

OBJECTIVE

This study aims to describe the prevalence rates of asthma symptoms in Brazil, its Regions and State capitals, according to data from the National Adolescent School-based Health Survey, 2012. Furthermore, it aims to compare the prevalence of asthma in the capitals evaluated by PeNSE 2012 with previous results of the International Study of Asthma and Allergies in Childhood (ISAAC).

METHODS

Cross sectional study of 9th grade students at public and private schools of all Brazilian states and the Federal District (Brasília). A self reported questionnaire containing items from the ISAAC was applied in order to identify the presence of asthma symptoms.

RESULTS

The results of PeNSE indicate a high prevalence of asthma symptoms (23.2%) and of reports of a previous medical diagnosis of asthma (12.4%). Of the five state capitals in which the PeNSE results were compared to the ISAAC, São Paulo, Curitiba and Porto Alegre presented an increase in the prevalence of asthma symptoms. In Salvador, there was a reduction.

CONCLUSION

Brazil is among the countries with the highest prevalence of asthma in the world, and the prevalence is still growing.

[Impact of obesity on response to therapy and pulmonary function in children with asthma]

OBJECTIVE

To investigate the effects of obesity on response to therapy and pulmonary function in children with asthma who receive inhaled corticosteroid (ICS) treatment.

METHODS

A total of 129 children with asthma were divided into two groups according to their body mass index: normal weight group (n=64) and obese group (n=65). The asthma control status and pulmonary function were compared between the two groups after one year of ICS treatment. The pulmonary function was expressed as percent forced expiratory volume in 1 second (FEV1%), percent predicted forced vital capacity (FVC%), peak expiratory flow (PEF), peak expiratory flow at 25% of vital capacity (PEF25), and peak expiratory flow at 50% of vital capacity (PEF50). The asthma control status was expressed as complete control rate, partial control rate, and uncontrolled rate. Sixty-eight healthy children were selected as the healthy control group.

RESULTS

There were significant differences in the indices of pulmonary function between the three groups before treatment (P<0.01); the healthy control group had the best values of pulmonary function, while the obese group had the worst values. After 1 year of treatment, the normal weight group showed significantly more improvements in FEV1% and FVC% than the obese group (P<0.01). However, there were no significant differences in improvements in PEF, PEF25, and PEF50 between the two groups. The complete control rate, partial control rate, and uncontrolled rate in the normal weight group were 72%, 19%, and 9%, respectively, while the rates in the obese group were 28%, 51%, and 22%, respectively; the normal weight group had a significantly better asthma control status than the obese group (P<0.01).

CONCLUSIONS

The asthmatic children with obesity have a significantly less improvement in large airway function and a poorer asthma control status after ICS treatment than those with the normal weight.

Childhood body mass index and wheezing disorders: a systematic review and meta-analysis

BACKGROUND

It has been claimed that overweight/obesity, childhood asthma and wheezing disorders are associated, although the results of observational studies have remained inconsistent. We conducted a systematic review and meta-analysis to investigate this.

METHODS

An online search of published papers linking childhood asthma and wheezing with overweight/obesity up to May 2014 using EMBASE and MEDLINE medical research databases was carried out. Summary odds ratios (OR) were estimated using random-effects models. Subgroup meta-analyses were performed to assess the robustness of risk associations and between-study heterogeneity.

RESULTS

A total of 38 studies comprising 1,411,335 participants were included in our meta-analysis. The summary ORs of underweight (<5th percentile), overweight (>85th to <95th percentile) and obesity (≥ 95 th percentile) were 0.85 (95% CI: 0.75 to 0.97; p = 0.02), 1.23 (95% CI: 1.17 to 1.29; p < 0.001) and 1.46 (95% CI: 1.36 to 1.57, p < 0.001), respectively. Heterogeneity was significant and substantial in all three weight categories, and not accounted for by pre-defined study characteristics.

CONCLUSION

Our results suggest that underweight is associated with a reduced risk of childhood asthma, and overweight and obesity are associated with an increased risk of childhood asthma. Although our findings assert that overweight/obesity and childhood asthma are associated, the causal pathway and temporal aspects of this relationship remain unanswered and deserve further epidemiological investigation.

Associations between central obesity and asthma in children and adolescents: a case-control study

INTRODUCTION

Evidence supports a significant yet weak association between high-body weight and asthma in children. However, most studies investigating the obesity-asthma link use Body Mass Index (BMI) to evaluate body fatness. The relationship between body fat distribution and asthma remains largely unknown, especially in children. This pediatric case-control investigation examined associations between central obesity/high-body weight and asthma diagnosis.

METHODS

Five-hundred and fourteen children (217 physician diagnosed asthma cases and 297 healthy controls) of 5-11 years were recruited. Height, weight and waist circumference were measured. Asthma symptoms, past medical history, personal lifestyle, socioeconomic status, diet and physical activity history were also collected.

RESULTS

A higher proportion of children with asthma were centrally obese [(≥90th waist percentile) 15.2 vs. 9.4%, p<0.0001; (≥90th waist-to-height ratio percentile) 39.6 vs. 24.2%, p<0.0001)]. Regression analyses revealed that centrally obese children were more likely to have asthma (high-waist circumference (OR = 1.99, 95% CI: 1.07-3.68) and high-waist circumference to height ratio (OR = 2.24, 95% CI: 1.47-3.40), following adjustment for various confounders. Overweight/obese participants (BMI defined) were more likely to be asthmatic [odds ratio (OR) = 1.52, 95% confidence interval (CI): 1.03-2.70)] when compared to controls.

CONCLUSIONS

Presence of central obesity and high-body weight (at least overweight) as assessed by waist circumference, waist-to-height ratio, and BMI are associated with asthma diagnosis. More studies are needed, especially in children and adolescents, to confirm these findings and better understand how body fat distribution impacts the obesity-asthma relationship.

The prevalence of wheezing and its association with serum zinc concentration in children and adolescents in Brazil

OBJECTIVE

To assess the influence of zinc serum status on the prevalence of wheezing in a sample of children and adolescents in Northeastern Brazil.

RESEARCH METHODS AND PROCEDURES

This is a cross-sectional study which included 592 students of 6-12 years old, from the public elementary schools of São Francisco do Conde, Bahia, Northeastern Brazil. Report of wheezing in the past 12 months was collected using a questionnaire of the International Study of Asthma and Allergies in Childhood Program (ISAAC) phase III, adapted to Portuguese. The determination of serum Zn levels was performed using a flame atomic absorption spectrometer. Data on anthropometric status, level of physical activity, pubertal development and socioeconomic information, for each participant were obtained. Multivariate logistic regression analyses were used to assess the associations of interest.

RESULTS

Of the students, 8.6% (95% CI 6.30-10.9) reported having wheezing. The mean (SD) serum zinc level was 114 (22.9 μg/dL). The results of the multiple logistic regression analysis showed, after adjustments, positive and significant association between low serum zinc levels and wheezing. Students categorized as being below the median for serum Zn concentration presented an almost 1.9-fold increase in the wheezing prevalence ratio (OR=1.9; 95% CI 1.03-3.53).

CONCLUSION

The main findings of this study suggest that the level of zinc may influence the risk of wheezing in late childhood on the study population.

Nutritional challenges for children in societies in transition

PURPOSE OF REVIEW

This review is to explore the childhood nutrition and health in relation to socioeconomic changes in transitional countries, and to describe the good experiences and policies in these countries to combat childhood nutritional challenges.

RECENT FINDINGS

Double burden of malnutrition - the coexistence of under-nutrition and over-nutrition in the same population - is a prominent public health concern in transitional countries. With rapid industrialization, these countries are facing a growing epidemic of overweight/obesity in children and adolescents. The increasing prevalence of childhood overweight/obesity is a likely consequence of behavioral changes, and accompanied with an increasing incidence of noncommunicable chronic diseases. Although remarkable improvement of childhood nutrition was achieved, the stunting growth and micronutrient deficiency remain to be child health issues in transitional countries.

SUMMARY

The social transition caused a broad range of nutrition-associated problems. Previous successful experiences indicated that if appropriate action is undertaken, the child nutritional problems accompanied with economic transition could be controlled to some extent. However, greater efforts are needed to improve the status of childhood nutrition in transitional countries.