Assessment of the diagnosis and prevalence of asthma in Australian indigenous children

Respiratory, birth and health economic measures for use with Indigenous Australian infants in a research trial: a modified Delphi with an Indigenous panel

Background

There is significant disparity between the respiratory health of Indigenous and non-Indigenous Australian infants. There is no culturally accepted measure to collect respiratory health outcomes in Indigenous infants. The aim of this study was to gain end user and expert consensus on the most relevant and acceptable respiratory and birth measures for Indigenous infants at birth, between birth and 6 months, and at 6 months of age follow-up for use in a research trial.

Methods

A three round modified Delphi process was conducted from February 2018 to April 2019. Eight Indigenous panel members, and 18 Indigenous women participated. Items reached consensus if 7/8 (≥80%) panel members indicated the item was ‘very essential’. Qualitative responses by Indigenous women and the panel were used to modify the 6 months of age surveys.

Results

In total, 15 items for birth, 48 items from 1 to 6 months, and five potential questionnaires for use at 6 months of age were considered. Of those, 15 measures for birth were accepted, i.e., gestational age, birth weight, Neonatal Intensive Care Unit (NICU) admissions, length, head circumference, sex, Apgar score, substance use, cord blood gas values, labour, birth type, health of the mother, number people living in the home, education of mother and place of residence. Seventeen measures from 1-to 6 months of age were accepted, i.e., acute respiratory symptoms (7), general health items (2), health care utilisation (6), exposure to tobacco smoke (1), and breastfeeding status (1). Three questionnaires for use at 6 months of age were accepted, i.e., a shortened 33-item respiratory questionnaire, a clinical history survey and a developmental questionnaire.

Conclusions

In a modified Delphi process with an Indigenous panel, measures and items were proposed for use to assess respiratory, birth and health economic outcomes in Indigenous Australian infants between birth and 6 months of age. This initial step can be used to develop a set of relevant and acceptable measures to report respiratory illness and birth outcomes in community based Indigenous infants.

Respiratory health profile of Indigenous Australian children and young adults

AIM

National data report respiratory illness to be the most common chronic illness in Australian Indigenous people aged <35 years but multi-centre data on specific diseases is sparse. Respiratory health is now known to be an independent predictor of future all-cause mortality and cardiovascular disease. We aimed to describe the respiratory health profile (clinical and spirometry data) of randomly recruited Indigenous Australian children and young adults from several sites.

METHODS

As part of the Indigenous Respiratory Reference Values study, 1278 Australian Indigenous children and young adults (aged 3-25 years) were recruited from nine communities (Queensland, n = 8; Northern Territory, n = 1). Self-reported and medical records were used to ascertain respiratory history. Participants were classified as 'healthy' if there was no current/previous respiratory disease history. Spirometry was performed on all participants and assessed according to forced expiratory volume at 1 s impairment.

RESULTS

Medical history data were available for 1245 (97.4%) and spirometry for 1106 participants (86.5%). Asthma and bronchitis were the most commonly reported respiratory conditions (city/regional 19.5% and rural/remote 16.8%, respectively). Participants with a history of any respiratory disease or those living in rural/remote communities had lower lung function compared to the 'healthy' group. Almost 52.0% of the entire cohort had mild-moderate forced expiratory volume at 1 s impairment (47.7% in 'healthy' group, 58.5% in 'respiratory history' group).

CONCLUSION

The high prevalence of poor respiratory health among Indigenous Australian children/young adults places them at increased risk of future all-cause mortality and cardiovascular disease. Respiratory assessments including spirometry should be part of the routine evaluation of Indigenous Australians.

Parents and school children reported symptoms and treatment of allergic disease differently

OBJECTIVE

To examine the difference between children and their parents in reporting symptoms and treatment of allergic diseases within a longitudinal birth cohort.

STUDY DESIGN AND SETTING

Information on symptoms and treatment of asthma, rhinitis, and eczema was obtained by questionnaire from 2,744 children (mean age: 12 years) and their parents. Differences between the responses were computed, and agreement assessed both absolutely and with kappa coefficient.

RESULTS

On 12 of the 15 questions, children's and parents' reports differed significantly. Asthma-related issues appeared significantly more prevalent in the children's reports, although kappa values were fair to very good. For symptoms of allergic rhinitis, the prevalence pattern varied, and kappa values were moderate to good. Parents reported a higher prevalence of eczema-related issues, but the children reported a significantly higher prevalence of eczema itself. Kappa values ranged from moderate to good.

CONCLUSION

Although reports of allergic symptoms and treatment by 12-year-old children and their parents were in moderate-to-good agreement, children reported more symptoms than their parents. Symptoms of allergic disease should be reported by children themselves, from the age of 11 years, whereas questions of prescribed pharmacological treatment could be answered either by the children or their parents.

Parent-reported ISAAC written questionnaire may underestimate the prevalence of asthma in children aged 10-12 years

OBJECTIVES

The aim of the present study was to compare the validity of the International Study of Asthma and Allergies in Childhood (ISAAC) written (WQ) and audiovisual questionnaires (AVQ 3.0) in two age-groups (10-12 and 13-15 years, respectively).

METHODS

The 13-15 year olds performed the self-completed the WQ and AVQ on the same day. The 10-12 year olds performed the self-completed the AVQ and the parent-completed WQ was completed by their parents. The methacholine challenge test was conducted in 10-12 year olds from one elementary school.

RESULTS

In 10-12 year olds, the AVQ detected a generally higher prevalence of asthma symptoms than WQ. In 13-15 year olds, this was reversed. In 10-12 year olds, poor agreement was found between the parent-completed WQ and the self-reported AVQ. In 13-15 year olds, moderate agreement was found between the self-reported WQ and AVQ. Low sensitivity was found, in predicting bronchial hyper-responsiveness (BHR) for all questions of both WQ and AVQ in 10-12 year olds. However, the AVQ had slightly higher sensitivity than WQ, with the exception of wheeze ever, although it was not statistically significant.

CONCLUSION

The ISAAC AVQ may be another effective instrument for assessing the prevalence of asthma symptoms in children aged 10-12 years, whereas the parent-reported-WQ may underestimate the prevalence of asthma symptoms in this age-group.

Update on treatment of childhood bronchiectasis unrelated to cystic-fibrosis

There are multiple aetiologies for childhood bronchiectasis unrelated to cystic fibrosis. Some of these aetiologies, such as those predisposing to recurrent lung infections, e.g. immunodeficiencies, require treatment of the underlying condition and disease-specific pulmonary pathogens within the airway. Regardless of aetiology, the treatments for bronchiectasis include antibiotics, airway clearance regimens, immunizations to prevent infections, and in some cases asthma therapies. The grade of evidence for specific treatments is low with few randomized controlled trials in children. Extrapolations of care provided to adults with bronchiectasis and patients with cystic fibrosis may not always be justified. Comprehensive care programs for children with bronchiectasis have demonstrated clinically relevant improvements over 2-7 year periods. Multi-center research is needed to rigorously evaluate current treatment practices for children with this disorder.

Cord blood versus age 5 mononuclear cell proliferation on IgE and asthma

BACKGROUND

Fetal immune responses following exposure of mothers to allergens during pregnancy may influence the subsequent risk of childhood asthma. However, the association of allergen-induced cord blood mononuclear cell (CBMC) proliferation and cytokine production with later allergic immune responses and asthma has been controversial. Our objective was to compare indoor allergen-induced CBMC with age 5 peripheral blood mononuclear cell (PBMC) proliferation and determine which may be associated with age 5 allergic immune responses and asthma in an inner city cohort.

METHODS

As part of an ongoing cohort study of the Columbia Center for Children's Environmental Health (CCCEH), CBMCs and age 5 PBMCs were cultured with cockroach, mouse, and dust mite protein extracts. CBMC proliferation and cytokine (IL-5 and IFN-gamma) responses, and age 5 PBMC proliferation responses, were compared to anti-cockroach, anti-mouse, and anti-dust mite IgE levels, wheeze, cough, eczema and asthma.

RESULTS

Correlations between CBMC and age 5 PBMC proliferation in response to cockroach, mouse, and dust mite antigens were nonsignificant. Cockroach-, mouse-, and dust mite-induced CBMC proliferation and cytokine responses were not associated with allergen-specific IgE at ages 2, 3, and 5, or with asthma and eczema at age 5. However, after adjusting for potential confounders, age 5 cockroach-induced PBMC proliferation was associated with anti-cockroach IgE, total IgE, and asthma (p < 0.05).

CONCLUSION

In contrast to allergen-induced CBMC proliferation, age 5 cockroach-induced PBMC proliferation was associated with age 5 specific and total IgE, and asthma, in an inner-city cohort where cockroach allergens are prevalent and exposure can be high.

The relationship between socio-economic and geographic factors and asthma among Canada's Aboriginal populations

OBJECTIVES

To examine the prevalence, exacerbations and management of asthma among Canada's Aboriginal populations, and its relationship to socio-economic and geographic factors.

STUDY DESIGN

Secondary analysis of a national cross-sectional questionnaire survey.

METHODS

Data were collected in 2000 and 2001 through a survey of Aboriginal children and adults residing on- and off-reserve as part of the 2001 Aboriginal People's Survey (APS). The asthma related outcome variables - physician-diagnosed asthma, attack in past year and regular use of inhalants - were examined in relation to socio-economic and geographic factors such as income, education, housing and location of residence. Statistical analyses were based on weighted univariate and multivariate logistic regressions.

RESULTS

The results show variations in asthma diagnosis, attacks and inhalant use across geographic location, socio-economic and demographic characteristics. Geographic location was found to be significantly associated with asthma for both adults and children, with those living in the northern territories, on-reserve or rural locations being the least likely to be diagnosed. Geographic location and Aboriginal identity were also found to be significantly associated with asthma medication use.

CONCLUSIONS

While these findings may suggest a "healthier" population in more remote locations, they alternatively point to a general pattern of under-diagnosis, potentially due to poor health care access, as is typical in more remote locations.

Chronic respiratory symptoms and diseases among indigenous children

Children from Indigenous populations experience more frequent, severe, and recurrent lower respiratory infections as infants and toddlers. The consequences of these infections are chronic lung disorders manifested by recurrent wheezing and chronic productive cough. These symptoms are aggravated more frequently by active and passive tobacco smoke exposure among Indigenous groups. Therapies for these symptoms, although not specific to children of Indigenous origins, are described as is the evidence for their use.

Stable prevalence of asthma symptoms in school-aged children in the Torres Strait region

BACKGROUND AND OBJECTIVE

To (i) determine if the prevalence of asthma has altered in two previously studied communities and (ii) obtain baseline measures in two further communities in the Torres Strait region, Australia.

METHODS

A population-based cross-sectional study of school-aged children was conducted. Five schools in four communities were selected: 361 children aged 5-17 years participated. The study used the same epidemiological tool that had been utilized to measure asthma prevalence (locally adapted International Study of Asthma and Allergy in Childhood questionnaire).

RESULTS

The overall response rate was 30%; response rates in individual communities ranged from 23% to 100%. The prevalence of self-reported wheezing in the last 12 months decreased from 10.7% to 6.6% (P = 0.109) on Thursday Island and from 3.1% to zero (P = 0.358) on Warraber Island. The percentage of children with asthma symptoms was lower in this current study but changes were not statistically significant. Overall self-reported prevalence of ever wheezing was 12.5%; 5.4% reported wheezing in the previous 12 months, 5.9% reported wheezing after exercise and 12.2% reported ever having asthma. There was considerable inter-community variation in the prevalence of symptoms.

CONCLUSIONS

Asthma prevalence in school-aged children living in the Torres Strait region remains high but, as in mainstream Australian children, the prevalence is stable.

Similar asthma prevalence estimates obtained from preadolescent and parent survey responses

OBJECTIVE

We compared agreement between child and parent responses to questions assessing prevalence of asthma and other severe respiratory symptoms.

STUDY DESIGN AND SETTING

Fifth-grade children enrolled in public schools and their parents separately completed a health survey, which included respiratory symptom questions from the International Study of Asthma and Allergies in Childhood (ISAAC). Agreement on respiratory symptom questions was assessed with Cohen's Kappa coefficient. Asthma prevalence estimates based on responses to several questions were also compared using child and parent data. The analysis was based on a study sample size of 230 matched parent and child questionnaires.

RESULTS

High levels of agreement (Kappa: 0.76 and 0.79) between child and parent responses were observed for current and lifetime asthma, and similar asthma prevalence estimates were obtained from child and parent response data. Five of the questions on potentially severe respiratory symptoms had low to fair levels of agreement (Kappa: -0.01 to 0.38), resulting in statistically significantly different prevalence estimates in three of the five symptoms.

CONCLUSIONS

Separate parent and child responses to a series of respiratory symptom and asthma questions yielded similar estimates for asthma prevalence but different estimates for the prevalence of several severe respiratory symptoms.

School-based asthma surveillance: a comparison of student and parental report

This study addressed the comparability of data obtained from a student-based and parent-based asthma and respiratory health survey. Our goal was to ascertain whether there were meaningful and systematic differences in asthma classification based on symptom and diagnosis reports obtained separately from students and their parents. A brief, written survey, based on the International Study of Asthma and Allergy in Children questionnaire, was administered to 6th through 10th grade students in two schools in Oakland, CA, USA. Students who reported asthma-like indicators for the previous 12-month period were defined as positive and a more extensive questionnaire was mailed home to those parents. A more refined classification of asthma based on parent report of indicators was compared with student report. Forty-four percent of 1298 students were classified as positive for current asthma-like symptoms and 50% of parent surveys were returned. For the positive students with parent surveys, 59% were classified as 'probable' for asthma based on the parent survey. Overall, the agreement between parent and students' classification was 70%, and 83% for students with a parent report of physician diagnosis of asthma. Students who were discordant with parents for physician diagnosis of asthma were more likely to be male, and more likely to have a parent report of unscheduled Emergency Department visit for wheezing or trouble breathing. Findings indicated that with the exception of medication, students reported asthma indicators more frequently that parents, independent of classification. Student report of physician diagnosis with a 12-month report of an asthma symptom was determined to be a good indicator of probable current asthma. Inclusion of or reliance on a parental questionnaire is not likely to improve the reliability of a school-based asthma surveillance program in our population.

Clinically diagnosed childhood asthma and follow-up of symptoms in a Swedish case control study

Background

Childhood asthma has risen dramatically not only in the western societies and now forms a major and still increasing public health problem. The aims of this study were to follow up at the age of ten the patterns of asthma symptoms and associations among children with a clinically diagnosed asthma in a sizeable urban-rural community and to in compare them with demographic controls using a standardised questionnaire.

Methods

In a defined region in Sweden with a population of about 150 000 inhabitants, all children (n = 2 104) born in 1990 were recorded. At the age of seven all primary care and hospital records of the 1 752 children still living in the community were examined, and a group of children (n = 191) was defined with a well-documented and medically confirmed asthma diagnosis. At the age of ten, 86 % of these cases (n = 158) and controls (n = 171) completed an ISAAC questionnaire concerning asthma history, symptoms and related conditions.

Results

Different types of asthma symptoms were highly and significantly over-represented in the cases. Reported asthma heredity was significantly higher among the cases. No significant difference in reported allergic rhinitis or eczema as a child was found between cases and controls. No significant difference concerning social factors or environmental exposure was found between case and controls. Among the control group 4.7 % of the parents reported that their child actually had asthma. These are likely to be new asthma cases between the age of seven and ten and give an estimated asthma prevalence rate at the age of ten of 15.1 % in the studied cohort.

Conclusion

A combination of medical verified asthma diagnosis through medical records and the use of self-reported symptom through the ISAAC questionnaire seem to be valid and reliable measures to follow-up childhood asthma in the local community. The asthma prevalence at the age of ten in the studied birth cohort is considerably higher than previous reports for Sweden. Both the high prevalence figure and allowing the three-year lag phase for further settling of events in the community point at the complementary roles of both hospital and primary care in the comprehensive coverage and control of childhood asthma in the community.

Adenosine Bronchial Provocation With Computerized Wheeze Detection in Young Infants With Prolonged Cough

BACKGROUND

Chronic cough in babies is often associated with bronchial hyperreactivity (BHR). The objective documentation of BHR in babies is difficult, and acoustic methods have been described (provocative concentration of a substance causing wheeze) for conducting bronchial provocation tests (BPTs). We conducted a study to evaluate automatic computerized wheeze detection (CWD) in determining BHR in young infants with prolonged cough, and its correlation with the subsequent development of wheezing.

METHODS

Infants aged < 24 months with prolonged cough (ie, > 2 months) underwent acoustic BPTs with the response determined by CWD and auscultation by a physician. Telephone interviews with parents were conducted after 1 month and yearly for the next 3 years.

RESULTS

A total of 28 infants who were 4 to 24 months old with prolonged cough were included in the study. Twenty of these infants (71.4%) had BHR as determined by a positive acoustic BPT result. In 11 of these 20 tests, the CWD occurred earlier, and in 9 tests it occurred at the same step as auscultation by a physician. Rhonchi or whistles often preceded wheezes. Seventeen of the 20 patients with BHR completed 3 years of follow-up. Of these, 14 had recurrent episodes of wheezing and shortness of breath, and 3 were well. Six of the eight adenosine-negative patients completed 3 years of follow-up and had no symptoms of BHR.

CONCLUSIONS

Acoustic BPT is a technically feasible test for the detection of BHR in young infants. CWD provides an earlier detection of wheeze than stethoscope auscultation. In our group of infants, a positive acoustic BPT result had high correlation with symptoms compatible with BHR over the next 3 years.

Snoring and its association with asthma in Indigenous children living in the Torres Strait and Northern Peninsula Area

OBJECTIVE

Respiratory health of Indigenous and minority ethnic groups in affluent countries is poorer than their non-minority counterparts and sleep disorders are no exception. In children, obstructive sleep apnoea has the potential to result in serious long-term consequences. In 1999, we studied 1650 children and adolescents living in the Torres Strait and the Northern Peninsula Area, Australia. Here we report prevalence of snoring in these communities and relate its association with asthma symptoms.

METHODS

A population-based cross-sectional study was conducted in the Torres Strait region. Five indigenous communities were randomly selected and information was collected using a structured face-to-face interview based on a standardized questionnaire. There was a 98% response rate, and 1650 children, 0-17 years of age, were included in the study.

RESULTS

Overall, the prevalence of snoring was 14.2% (95% CI 12.5-15.9); 3.6% (95% CI 2.7-4.6) reported snorting, and 6% (95% CI 4.9-7.2) reported restless sleep. The prevalence of snoring was significantly higher among males (17.1% for males and 10.8 for females, P = 0.005). Children were five times more likely to have experienced snoring and snorting if they reported wheezing in the last 12 months.

CONCLUSION

We conclude that the prevalence of symptoms suggestive of obstructive sleep problems is relatively high in children of this region. This highlights the need for awareness among the community patients and physicians about the problem of obstructive sleep-disordered breathing, especially in children with asthma, and for the need for further studies to measure prevalence of sleep breathing disorders among Indigenous Australians.