Socioeconomic risk factors for asthma in Chilean young adults

Characterization of the upper respiratory tract microbiota in Chilean asthmatic children reveals compositional, functional, and structural differences

Around 155 million people worldwide suffer from asthma. In Chile, the prevalence of this disease in children is around 15% and has a high impact in the health system. Studies suggest that asthma is caused by multiple factors, including host genetics, antibiotic use, and the development of the airway microbiota. Here, we used 16S rRNA high-throughput sequencing to characterize the nasal and oral mucosae of 63 asthmatic and 89 healthy children (152 samples) from Santiago, Chile. We found that the nasal mucosa was dominated by a high abundance of Moraxella, Dolosigranulum, Haemophilus, Corynebacterium, Streptococcus, and Staphylococcus. In turn, the oral mucosa was characterized by a high abundance of Streptococcus, Haemophilus, Gemella, Veillonella, Neisseria, and Porphyromonas. Our results showed significantly (P < 0.001) lower alpha diversity and an over-abundance of Streptococcus (P < 0.01) in nasal samples from asthmatics compared to samples from healthy subjects. Community structure, as revealed by co-occurrence networks, showed different microbial interactions in asthmatic and healthy subjects, particularly in the nasal microbiota. The networks revealed keystone genera in each body site, including Prevotella, Leptotrichia, and Porphyromonas in the nasal microbiota, and Streptococcus, Granulicatella, and Veillonella in the oral microbiota. We also detected 51 functional pathways differentially abundant on the nasal mucosa of asthmatic subjects, although only 13 pathways were overrepresented in the asthmatic subjects (P < 0.05). We did not find any significant differences in microbial taxonomic (composition and structure) and functional diversity between the oral mucosa of asthmatic and healthy subjects. This study explores for the first time the relationships between the upper respiratory airways bacteriome and asthma in Chile. It demonstrates that the nasal cavity of children from Santiago harbors unique bacterial communities and identifies potential taxonomic and functional biomarkers of pediatric asthma.

Impact of socioeconomic factors and house cleaning on asthma control in women

Background: It is known that socioeconomic factors affect various chronic diseases and also might affect asthma control. Exposure to house-cleaning products has been shown to impact both the onset and control of asthma. Objective: This study aimed to determine the effect of socioeconomic factors and house cleaning on asthma control of women with asthma. Methods: Adult women with asthma (N = 204) with informed consent were included in this single-center, cross-sectional observational study. A questionnaire, including items related to demographic, clinical, and socioeconomic features of the patients, was administered with a face-to-face interview by an investigator. A test to assess the level of asthma control was used to classify the patients as uncontrolled, partially controlled, and fully controlled. Wealth perception was measured with a visual analog scale. Investigated socioeconomic features were household size, monthly household income, education status, working status, occupation, and education status of the mothers of the patients. Results: Of the 204 adult female patients, 68.6% had uncontrolled, 14.7% had partially controlled, and 16.7% had fully controlled asthma. Partially or fully controlled asthma was higher (odds ratio [OR] 2.6 [95% confidence interval [CI], 1.09-6.22]) in the highest income quantile compared with the lowest income quantile. Asthma was better controlled in women with a visual analog scale score of wealth perception ≥ 7 (OR 1.93 [95% CI, 1.04-3.59]) and, in those who cleaned their houses, one to two times per week compared with zero times per week (OR 2.94 [95% CI, 1.19-7.26]). Conclusion: Having a higher household income was the only socioeconomic factor associated with better asthma control. After adjusting for age, duration of asthma, and comorbidities, better asthma control was significantly associated with cleaning the house one to two times a week.

Socioeconomic, comorbidity, lifestyle, and quality of life comparisons between chronic rhinosinusitis phenotypes

BACKGROUND

Chronic rhinosinusitis (CRS) is a heterogeneous group of inflammatory sinonasal disorders with key defining symptoms, but traditionally separated into phenotypes by clinical/endoscopic findings. It is not known whether the two phenotypes have differing socioeconomic, comorbidity, and lifestyle differences. This analysis of the Chronic Rhinosinusitis Epidemiology Study (CRES) database sought to analyze any key differences in the socioeconomic variables between those with CRS with nasal polyps (CRSwNPs) and those without nasal polyps (CRSsNPs). We also sought to analyze differences in comorbidities, lifestyle, and quality of life.

METHODS

Patients with a confirmed diagnosis of CRS in secondary and tertiary care outpatient settings in the UK were invited to participate in a questionnaire-based case-control study. Variables included demographics, socioeconomic factors, comorbidities, lifestyle factors, and health-related quality of life (HRQoL) (level 3 evidence).

RESULTS

A total of 1204 patients' data were analyzed: 553 CRSsNP and 651 CRSwNP participants. The key socioeconomic variables did not demonstrate any notable differences, nor did lifestyle variables other than alcohol consumption being higher in those with CRSwNP (P = .032), but the latter was not significant after adjusting for age and sex. Aside from confirmation of asthma being more common in CRSwNP, it was notable that this group complained less of upper respiratory tract infections (URTIs), and CRSsNP participants showed evidence of worse HRQoL scores in respect of body pain (P = .001).

CONCLUSIONS

Patients with CRSwNP experience higher rates of asthma and lower rates of URTIs; patients with CRSsNP have worse body pain scores. Otherwise, there are no demonstrable significant socioeconomic, comorbidity, lifestyle, or quality of life differences between the two phenotypes.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Ideal cardiovascular health in urban Jamaica: prevalence estimates and relationship to community property value, household assets and educational attainment: a cross-sectional study

OBJECTIVE

Ideal cardiovascular health (ICH) is associated with greater longevity and reduced morbidity, but no research on ICH has been conducted in Jamaica. We aimed to estimate the prevalence of ICH in urban Jamaica and to evaluate associations between ICH and community, household, and individual socioeconomic status (SES).

DESIGN

Cross-sectional study.

SETTING

Urban communities in Jamaica.

PARTICIPANTS

360 men and 665 women who were urban residents aged ≥20 years from a national survey, the Jamaica Health and Lifestyle Survey 2016-2017.

EXPOSURES

Community SES, using median land values (MLV); household SES, using number of household assets; and individual SES, using education level.

PRIMARY OUTCOME

The main outcome variable was ICH, defined as having five or more of seven ICH characteristics (ICH-5): current non-smoking, healthy diet, moderate physical activity, normal body mass index, normal blood pressure, normal glucose and normal cholesterol. Prevalence was estimated using weighted survey design and logistic regression models were used to evaluate associations.

RESULTS

The prevalence of overall ICH (seven characteristics) was 0.51%, while the prevalence of ICH-5 was 22.9% (male 24.5%, female 21.5%, p=0.447). In sex-specific multivariable models adjusted for age, education, and household assets, men in the lower tertiles of community MLV had lower odds of ICH-5 compared with men in the upper tertile (lowest tertile: OR 0.33, 95% CI 0.12 to 0.91, p=0.032; middle tertile: OR 0.46, 95% CI 0.20 to 1.04, p=0.062). Women from communities in the lower and middle tertiles of MLV also had lower odds of ICH-5, but the association was not statistically significant. Educational attainment was inversely associated with ICH-5 among men and positively associated among women.

CONCLUSION

Living in poorer communities was associated with lower odds of ICH-5 among men in Jamaica. The association between education level and ICH-5 differed in men and women.

Lifetime overweight and adult asthma: 1978/1979 Ribeirão Preto Birth Cohort, São Paulo, Brazil

Studies focusing on obesity and asthma frequently consider the weight at a given time; thus, modeling pathways through lifetime overweight may contribute to elucidate temporal aspects in this relationship. This study modeled the pathways in the association of lifetime overweight with asthma in adult life, using data from the 1978/1979 Birth Cohort, Ribeirão Preto, São Paulo, Brazil (n = 2,063) at birth (baseline), school age (9/11 years) and adult age (23/25 years). A theoretical model was proposed to explore the effects of lifetime overweight on asthma in adult life analyzed by structural equation modeling. Parental obesity (SC - standardized coefficenttotal = 0.211, p < 0.001; SCdirect = 0.115, p = 0.007) and overweight at school age (SCtotal = 0.565, p < 0.0001; SCdirect = 0.565, p < 0.0001) were associated with overweight in adult life. Parental obesity (SCdirect = 0.105, p = 0.047) and nutritional status at birth (SCtotal = -0.124, p = 0.009; SCdirect = -0.131, p = 0.007) were associated with asthma in adult life. A higher "current adult socieconomic situation" was inversely associated to overweight (SCdirect = -0.171, p = 0.020) and to asthma in adult life (SCtotal = -0.179, p = 0.041; SCdirect = -0.182, p = 0.039). Parental obesity showed a transgenerational effect in weight, triggering to childhood and adulthood overweight. Parallel to underweight at birth, parental obesity was also a risk to asthma in adult life. While, the socioeconomic status in adult life protected from both, overweight and asthma.

Allergic diseases, smoking, and environmental exposure among university students in Lebanon

INTRODUCTION

Smoking habits among university students in Lebanon are not clearly identified, and studies correlating these habits to asthma and allergic diseases are lacking. The primary objective of this study is to assess asthma and allergic diseases' predictors, particularly cigarette and/or waterpipe smoking and other environmental exposures, among university students. A second objective is to evaluate the potential role of these predictors as correlates of health-related self-assessment.

METHODS

A cross-sectional study, using a proportionate cluster sample of 3000 Lebanese students in both public and private universities, was conducted between January 2015 and December 2015.

RESULTS

The number of smokers at home, living close to an electricity generator and exposure to sand and dust significantly increased the odds of having asthma or allergic diseases (p = 0.015; OR = 1.183; p = 0.01; OR = 2.062; p = 0.001; OR = 3.558 respectively). Having tried cigarette smoking and having an air conditioner inside the means of transportation would decrease the odds of having asthma or allergic diseases by around 68% and 56.1% respectively (p = 0.009; OR_a = 0.320; p = 0.01; OR_a = 0.439 respectively).

CONCLUSION

Although students with asthma or allergic diseases tended to avoid all identifiable atopic risk factors, lesser known environmental factors such as living close to an electricity generator, exposure to sand and dust, and exposure to car exhaust fumes were associated with a higher risk of asthma and a decrease in health related self-assessment. Students with asthma and allergic diseases smoked cigarettes and waterpipe at similar percentages, but cigarette smokers had a lower health related self-assessment.

ASSESSMENT OF SOCIOECONOMIC STATUS AND CONTROL OF ASTHMA IN ADULTS

BACKGROUND

Asthma is a chronic disease which places considerable economic, social and public health burdens on the society. Education, occupation and income are the most widely used indicators of socioeconomic status (SES). Studies have shown increased asthma hospital admissions for those who are materially deprived and increased asthma severity in low social class groups. The aim of this study is to determine the impact of socioeconomic status on control of asthma in adults.

METHOD

The study was a cross-sectional analytical one, conducted over a year at the Medical Outpatient Clinic of the University College Hospital Ibadan. The study population was composed of 355 randomly selected adults aged between 18years and 55years with an established diagnosis of asthma already on treatment.

RESULTS

Respondents with monthly income of 40000 and above had a higher proportion with good asthma control (74.1%) compared to those that earned 10000 to 39999 (69.0%) and less than 10000 (47.8%). This was statistically significant. Respondents in occupational class I/II had a slightly higher proportion with good asthma control (70.9%) compared to those in occupation class III/IV (70.1%) and occupation class V/VI (50.6%). This was statistically significant at p = 0.003.

CONCLUSION

Respondents in the higher occupational class had better asthma control than respondents in the lower occupational class. Respondents who were earning 40000 and above as monthly income had better control of asthma than other respondents. After adjusting for other variables, the predictor of good asthma control was monthly income of the respondents.

Ventilatory function in young adults and dietary antioxidant intake

Dietary antioxidants may protect against poor ventilatory function. We assessed the relation between ventilatory function and antioxidant components of diet in young Chileans. Forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC), and the ratio FEV₁/FVC were measured in 1232 adults aged 22–28 years, using a Vitalograph device. Dietary intake was ascertained with a food frequency questionnaire (FFQ) designed for this study, from which nutrient and flavonoid intakes were estimated. Dietary patterns were derived with Principal Component Analysis (PCA). After controlling for potential confounders, dietary intake of total catechins was positively associated with FVC (Regression coefficient (RC) of highest vs. lowest quintile of intake 0.07; 95% CI 0.01 to 0.15; p per trend 0.006). Total fruit intake was related to FVC (RC of highest vs. lowest quintile 0.08; 95% CI 0.003 to 0.15; p per trend 0.02). Intake of omega 3 fatty acids was associated with a higher FEV₁ (RC for highest vs. lowest quintile 0.08; 95% CI 0.01 to 0.15 L; p per trend 0.02) and with FVC 0.08 (RC in highest vs. lowest quintile of intake 0.08, 95% CI 0.001 to 0.16; p per trend 0.04). Our results show that fresh fruits, flavonoids, and omega 3 fatty acids may contribute to maintain ventilatory function.

Schistosome infection is negatively associated with mite atopy, but not wheeze and asthma in Ghanaian schoolchildren

BACKGROUND

Epidemiological evidence suggests that helminth infection and rural living are inversely associated with allergic disorders.

OBJECTIVE

The aim of the study was to investigate the effect of helminth infections and urban versus rural residence on allergy in schoolchildren from Ghana.

METHODS

In a cross-sectional study of 1385 children from urban-high socio-economic status (SES), urban-low SES and rural schools, associations between body mass index (BMI), allergen-specific IgE (sIgE), parasitic infections and allergy outcomes were analysed. Allergy outcomes were skin prick test (SPT) reactivity, reported current wheeze and asthma.

RESULTS

Helminth infections were found predominantly among rural subjects, and the most common were hookworm (9.9%) and Schistosoma spp (9.5%). Being overweight was highest among urban-high SES (14.6%) compared to urban-low SES (5.5%) and rural children (8.6%). The prevalence of SPT reactivity to any allergen was 18.3%, and this was highest among rural children (21.4%) followed by urban-high SES (20.2%) and urban-low SES (10.5%) children. Overall, SPT reactivity to mite (12%) was most common. Wheeze and asthma were reported by 7.9% and 8.3%, respectively. In multivariate analyses, factors associated with mite SPT were BMI (aOR 2.43, 95% CI 1.28-4.60, P = 0.007), schistosome infection (aOR 0.15, 95% CI 0.05-0.41) and mite sIgE (aOR 7.40, 95% CI 5.62-9.73, P < 0.001) but not area. However, the association between mite IgE and SPT differed by area and was strongest among urban-high SES children (aOR = 15.58, 95% CI 7.05-34.43, P < 0.001). Compared to rural, urban-low SES area was negatively associated with current wheeze (aOR 0.41, 95% CI 0.20-0.83, P = 0.013). Both mite sIgE and mite SPT were significantly associated with current wheeze and asthma.

CONCLUSION AND CLINICAL RELEVANCE

Infection with schistosomes appeared to protect against mite SPT reactivity. This needs to be confirmed in future studies, preferably in a longitudinal design where schistosome infections are treated and allergic reactions reassessed.

Ventilatory function and cardiovascular disease risk factors: a cross-sectional study in young adults

Background

The association between impaired lung function and cardiovascular disease (CVD) risk factors has been shown in adults. However, there is little evidence of such an association in young adults, particularly from South America, where the burden of CVD and chronic obstructive pulmonary disease (COPD) is as high as that observed in more developed countries. We therefore investigated the relation between CVD risk factors including metabolic syndrome (MS), and lung function status in young adults from Chile.

Methods

970 subjects from a sample of 998 adults born between 1974 and 1978 in Limache, Chile, were studied. A Spanish translation of the European Community Respiratory Health Survey (ECRHS) questionnaire was used. Forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) were measured. Weight, height, waist circumference (WC), blood pressure, Homeostatic model assessment (HOMA-IR), triglycerides, high density lipoprotein (HDL), glycaemia, and metabolic syndrome (MS) were also assessed.

Results

The prevalence of MS was 11.8%. A lower FEV₁ and lower FVC were associated with having MS (β-coefficient -0.13; 95% Confidence Interval [CI] -0.21 to -0.05, and β-coefficient -0.18; 95% CI -0.27 to -0.09, respectively). Both spirometric measures were also negatively associated with having an elevated HOMA-IR (β-coefficient for FEV₁ -0.08; 95% CI -0.13 to -0.03, and β-coefficient for FVC -0.11; 95% CI -0.17 to -0.05). In males only, a lower FEV₁ and FVC were associated with having elevated triglycerides (β-coefficient highest vs. lowest tertile -0.13, 95% CI -0.24 to -0.03, and β-coefficient -0.13, 95% CI -0.25 to -0.01, respectively). In women, a higher FEV₁ and FVC were statistically significantly related to having higher levels of HDL. Ventilatory function was unrelated to hypertension or WC in this population.

Conclusion

In this population-based study of young adults, a poorer ventilatory function was associated with many CVD risk factors. Endeavours to understand better causality issues of such associations are warranted.

Social determinants of childhood asthma symptoms: an ecological study in urban Latin America

Asthma is an important public health problem in urban Latin America. This study aimed to analyze the role of socioeconomic and environmental factors as potential determinants of asthma symptoms prevalence in children from Latin American (LA) urban centers. We selected 31 LA urban centers with complete data, and an ecological analysis was performed. According to our theoretical framework, the explanatory variables were classified in three levels: distal, intermediate, and proximate. The association between variables in the three levels and prevalence of asthma symptoms was examined by bivariate and multivariate linear regression analysis weighed by sample size. In a second stage, we fitted several linear regression models introducing sequentially the variables according to the predefined hierarchy. In the final hierarchical model Gini Index, crowding, sanitation, variation in infant mortality rates and homicide rates, explained great part of the variance in asthma prevalence between centers (R(2) = 75.0 %). We found a strong association between socioeconomic and environmental variables and prevalence of asthma symptoms in LA urban children, and according to our hierarchical framework and the results found we suggest that social inequalities (measured by the Gini Index) is a central determinant to explain high prevalence of asthma in LA.

Cohort profile: The Limache, Chile, birth cohort study

The Limache cohort was set up to assess the programming and life course events hypotheses in relation to cardiovascular risk factors and chronic respiratory conditions, especially asthma, in the context of an unprecedented economic growth in Chile. The cohort was a representative sample of 1232 participants born between 1974 and 1978 in the hospital of Limache. The study includes data collected at birth, during the 1st year of life, at 22 to 28 years (collected between 2000 and 2002) and at 32 to 38 years (collected between 2010 and 2012). The data collected include anthropometric measurements at birth, 1st year of life and in adulthood, socio-economic and demographic data, lifestyle information including smoking, alcohol consumption and food intake, respiratory symptoms, lung function, broncho-reactivity to methacholine and skin prick reaction to eight allergens, measurement of cardiovascular risk factors and information on common mental health, mainly in the most recent study. The principal researchers welcome collaborative projects, especially those that will compare similar data sets in other settings.

Relative residential property value as a socio-economic status indicator for health research

Background

Residential property is reported as the most valuable asset people will own and therefore provides the potential to be used as a socio-economic status (SES) measure. Location is generally recognised as the most important determinant of residential property value.

Extending the well-established relationship between poor health and socio-economic disadvantage and the role of residential property in the overall wealth of individuals, this study tested the predictive value of the Relative Location Factor (RLF), a SES measure designed to reflect the relationship between location and residential property value, and six cardiometabolic disease risk factors, central obesity, hypertriglyceridemia, reduced high density lipoprotein (HDL), hypertension, impaired fasting glucose, and high low density lipoprotein (LDL). These risk factors were also summed and expressed as a cumulative cardiometabolic risk (CMR) score.

Methods

RLF was calculated using a global hedonic regression model from residential property sales transaction data based upon several residential property characteristics, but deliberately blind to location, to predict the selling price of the property. The predicted selling price was divided by the actual selling price and the results interpolated across the study area and classified as tertiles. The measures used to calculate CMR were collected via clinic visits from a population-based cohort study. Models with individual risk factors and the cumulative cardiometabolic risk (CMR) score as dependent variables were respectively tested using log binomial and Poisson generalised linear models.

Results

A statistically significant relationship was found between RLF, the cumulative CMR score and all but one of the risk factors. In all cases, participants in the most advantaged and intermediate group had a lower risk for cardio-metabolic diseases. For the CMR score the RR for the most advantaged was 19% lower (RR = 0.81; CI 0.76-0.86; p <0.0001) and the middle group was 9% lower (RR = 0.91; CI 0.86-0.95; p <0.0001) than the least advantaged group.

Conclusions

This paper advances the understanding of the nexus between place, health and SES by providing an objective spatially informed SES measure for testing health outcomes and reported a robust association between RLF and several health measures.

Perception of dietary food items as food allergens in asthmatic individuals in north Indian population

BACKGROUND AND OBJECTIVE

The role of food allergy in asthma is well recognized but is poorly quantified. The aim of the present study was to document perceived food items as allergens and to determine their association with age, sex, socioeconomic status (SES), family history of asthma, smoking history, duration of illness, and total serum immunoglobulin (Ig)E.

METHODS

A total of 261 clinically and spirometrically diagnosed patients with asthma were included in this study on an accrual basis. Of these, 237 patients thought that their asthma became aggravated after consumption of at least 1 food item. The perceived food item allergy and its association with age, sex, SES, family history of asthma, smoking history, duration of illness, and total serum IgE were assessed using a detailed, open-ended questionnaire.

RESULTS

Food items were perceived as main allergens by 90% (237/261) of responders. Sixty-five percent (154/237) of patients who perceived at least 1 food item as an allergen had high total serum IgE levels. Of 22 suspected food items, 16 were significantly (p < 0.05) associated with at least 1 of the 6 study parameters.

CONCLUSION

Food items play a major role as food allergens on the basis of perception in asthmatic individuals. Some suspected food items are significantly associated with the demographic profile of asthmatic individuals.

A review of equity issues in quantitative studies on health inequalities: the case of asthma in adults

BACKGROUND

The term 'inequities' refers to avoidable differences rooted in injustice. This review examined whether or not, and how, quantitative studies identifying inequalities in risk factors and health service utilization for asthma explicitly addressed underlying inequities. Asthma was chosen because recent decades have seen strong increases in asthma prevalence in many international settings, and inequalities in risk factors and related outcomes.

METHODS

A review was conducted of studies that identified social inequalities in asthma-related outcomes or health service use in adult populations. Data were extracted on use of equity terms (objective evidence), and discussion of equity issues without using the exact terms (subjective evidence).

RESULTS

Of the 219 unique articles retrieved, 21 were eligible for inclusion. None used the terms equity/inequity. While all but one article traced at least partial pathways to inequity, only 52% proposed any intervention and 55% of these interventions focused exclusively on the more proximal, clinical level.

CONCLUSIONS

Without more in-depth and systematic examination of inequities underlying asthma prevalence, quantitative studies may fail to provide the evidence required to inform equity-oriented interventions to address underlying circumstances restricting opportunities for health.

Asthma: time to confront some inconvenient truths

Despite major advances in the understanding of the pathogenesis of asthma and improvements in management, the accompanying benefits from public health initiatives and clinical practice have arguably been less than expected. For example, there are no effective public health strategies or treatment regimes that reduce the risk of developing asthma or influence its natural history. These represent priority areas for future translational research, which would need to investigate genetic and environmental interactions and vaccine strategies. In terms of asthma management it is tempting to focus on novel drug therapies; however, a case can be made that the priority is to undertake research that leads to improvements in the use of existing treatments through public health and primary care initiatives. Guidelines represent an important component of this approach, with recommendations for asthma imbedded within respiratory guidelines that can be implemented in the developing world where other acute and chronic respiratory disorders are common. This approach offers the best opportunity to close the gap between what is currently achieved in asthma management and that which is potentially achievable.

The Jamaica asthma and allergies national prevalence survey: rationale and methods

Background

Asthma is a significant public health problem in the Caribbean. Prevalence surveys using standardized measures of asthma provide valid prevalence estimates to facilitate regional and international comparisons and monitoring of trends. This paper describes methods used in the Jamaica Asthma and Allergies National Prevalence Survey, challenges associated with this survey and strategies used to overcome these challenges.

Methods/Design

An island wide, cross-sectional, community-based survey of asthma, asthma symptoms and allergies was done among adults and children using the European Community Respiratory Health Survey Questionnaire for adults and the International Study of Asthma and Allergies in Children. Stratified multi-stage cluster sampling was used to select 2, 163 adults aged 18 years and older and 2, 017 children aged 2-17 years for the survey. The Kish selection table was used to select one adult and one child per household. Data analysis accounted for sampling design and prevalence estimates were weighted to produce national estimates.

Discussion

The Jamaica Asthma and Allergies National Prevalence Survey is the first population- based survey in the Caribbean to determine the prevalence of asthma and allergies both in adults and children using standardized methods. With response rates exceeding 80% in both groups, this approach facilitated cost-effective gathering of high quality asthma prevalence data that will facilitate international and regional comparison and monitoring of asthma prevalence trends. Another unique feature of this study was the partnership with the Ministry of Health in Jamaica, which ensured the collection of data relevant for decision-making to facilitate the uptake of research evidence. The findings of this study will provide important data on the burden of asthma and allergies in Jamaica and contribute to evidence-informed planning of comprehensive asthma management and education programs.

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.

Contact to cat or dog, allergies and parental education

Whether or not associations between animal contact and allergy/atopy are homogeneous across social strata has not yet been investigated. The aim of this study was to estimate the association between animal contact (cat, dog) and allergy/atopy in 6-yr-old school beginners, stratified by parental educational level. A total of 30794, 6-yr old children participated in cross-sectional studies between 1991 and 2000 in Germany. Allergic sensitization to common aeroallergens and symptoms and diagnoses of atopic diseases (asthma, eczema, hay fever) were the dependent variables. Contact with dog/cat were the independent variables. Logistic regression was used to adjust for confounding. Analyses were stratified for parental education. Prevalences of hay fever, eczema, specific sensitization to pollen and house dust mite increased, while the prevalence of contact to cat and dog decreased with parental educational level. Globally significant positive associations between cat contact and sensitization to cat (interaction significant) and between dog contact and wheezing remained significant in the highest and medium/highest educational strata respectively. A globally significant inverse association between cat contact and hay fever remained significant in the highest educational stratum only. The inverse association of contact to dog with eczema was globally significant, but not in the strata. When estimating the associations between animal contact and allergy/atopy in children, effect modification by social status should be considered. Cat contact seems to increase the odds of sensitization to cat only in children whose parents have a high level of education.

Individual-level socioeconomic status is associated with worse asthma morbidity in patients with asthma

BACKGROUND

Low socioeconomic status (SES) has been linked to higher morbidity in patients with chronic diseases, but may be particularly relevant to asthma, as asthmatics of lower SES may have higher exposures to indoor (e.g., cockroaches, tobacco smoke) and outdoor (e.g., urban pollution) allergens, thus increasing risk for exacerbations.

METHODS

This study assessed associations between adult SES (measured according to educational level) and asthma morbidity, including asthma control; asthma-related emergency health service use; asthma self-efficacy, and asthma-related quality of life, in a Canadian cohort of 781 adult asthmatics. All patients underwent a sociodemographic and medical history interview and pulmonary function testing on the day of their asthma clinic visit, and completed a battery of questionnaires (Asthma Control Questionnaire, Asthma Quality of Life Questionnaire, and Asthma Self-Efficacy Scale). General Linear Models assessed associations between SES and each morbidity measure.

RESULTS

Lower SES was associated with worse asthma control (F = 11.63, p < .001), greater emergency health service use (F = 5.09, p = .024), and worse asthma self-efficacy (F = 12.04, p < .01), independent of covariates. Logistic regression analyses revealed that patients with <12 years of education were 55% more likely to report an asthma-related emergency health service visit in the last year (OR = 1.55, 95%CI = 1.05-2.27). Lower SES was not related to worse asthma-related quality of life.

CONCLUSIONS

Results suggest that lower SES (measured according to education level), is associated with several indices of worse asthma morbidity, particularly worse asthma control, in adult asthmatics independent of disease severity. Results are consistent with previous studies linking lower SES to worse asthma in children, and add asthma to the list of chronic diseases affected by individual-level SES.

Gender differences in asthma prevalence: variations with socioeconomic disadvantage

BACKGROUND AND OBJECTIVE

Socioeconomic inequalities in health have been shown to vary for different diseases and by gender. This study aimed to examine gender differences in associations between asthma and socioeconomic disadvantage.

METHODS

Socioeconomic variables were assessed among men and women in the North West Adelaide Health Study, a representative population cohort (n = 4060) aged 18 years and over in metropolitan South Australia. Asthma was determined from spirometry and self-reported doctor diagnosis.

RESULTS

The prevalence of asthma was 12.0% (95% CI: 11.1-13.1), and was significantly higher among women (13.5%) than men (10.5%). For participants aged 18-64 years a higher prevalence of asthma was associated with an education level of secondary school or lower, or not being in the paid labour force among men, and with a gross annual household income of $20,000 or less among women. Among socioeconomically advantaged groups, the prevalence of asthma was significantly higher among women than men.

CONCLUSIONS

Socioeconomic disadvantage was associated with higher asthma prevalence, although this varied by gender depending on the indicator of socioeconomic position used. Men with low education or those not employed in the paid labour force had higher asthma prevalence than more socioeconomically advantaged men. Women with low income had higher asthma prevalence than those with higher income. Among all socioeconomically advantaged groups, and also the low-income group, women experienced a higher prevalence of asthma than men.

Environmental determinants of asthma among school children aged 13-14 in and around Polokwane, Limpopo Province, South Africa

Asthma has become a public health issue since the 1960’s. Factors associated with asthma are environmental and genetic. This study is based on a random sample of 742 students aged 13–14 attending various schools at Polokwane, in the Province of Limpopo in South Africa. Survey logistic regression and multi-level analyses were used for data analysis. The study identifies three key determinants of asthma at the district, school and individual levels. The study shows that persistent cough (OR = 4.01), exposure to smoke at the household level (OR = 2.39) and lack of access to flush toileta at the household level (OR = 1.89) are key predictors of asthma in children. Variability at the level of districts accounts for 46% of total variance. Variability at the level of schools accounts for 33% of total variance.

Relationship between oxidative stress-related biomarkers and antioxidant status with asthma and atopy in young adults: a population-based study

BACKGROUND AND AIM

Enhanced oxidative stress has been described in adults who suffer from symptoms of asthma and poor lung function. This study assessed the relation between markers of oxidative stress and antioxidant status and lung function, symptoms of asthma, atopy and bronchial hyperresponsiveness (BHR) in young adults.

METHODS

A sub-sample of 589 individuals aged 22-28 years, selected from a total of 1232 included in a survey assessing early and current risk factors for chronic diseases, participated in the study. Participants were from an agricultural area of Chile, responded to a Spanish version of the European Community Respiratory Health Survey questionnaire, were skin tested to eight allergens, and challenged with methacholine to assess BHR. Five hundred and eighty-five individuals had measures of plasma biomarkers ferric reducing ability of plasma, uric acid, protein carbonyls and 564 had 8-iso-prostaglandin F(2alpha) (8-iso-PGF(2alpha)) assessed.

RESULTS

All participants had detectable plasma 8-iso-PGF(2alpha) and carbonyl levels. There was no indication for an association between markers of antioxidant status or oxidative stress with any of the outcomes studied.

CONCLUSION

The levels of oxidative stress-related biomarkers and antioxidant status in plasma may not be related to asthma in the general population in the absence of more severe symptoms or exacerbations.

Risk factors for asthma and allergic diseases in school children across Lebanon

Introduction:

Childhood asthma is one of important diseases of childhood. There is no known prevalence of asthma and allergic diseases in Lebanon. This study was conducted with a secondary objective of finding the odds of exposure to asthma, allergic rhinitis and eczema potential risk factors in Lebanese children.

Material and methods:

It is a cross-sectional study on children in public and private schools. A sample of 22 schools participated, where standardized written core questionnaires were distributed. 5–12 year old students completed the questionnaires at home, while 13–14 year old students filled it in class.

Results:

5522 children were evaluated for asthma, allergic rhinitis and atopic eczema prevalence and their associated factors. These diseases seem to be similarly affected by parental respiratory problems, parental smoking, infancy gastroesophageal reflux, recurrent otitis, and previous pertussis. Humidity on the bedroom walls is associated with both asthma and allergic rhinitis, a spongy pillow with both allergic rhinitis and eczema, animal possession with asthma, and noncotton mattress with atopic eczema. The adjusted odds ratios for significant associations varied between 1.25 and 3 (0.0001 < p-value < 0.01).

Conclusion:

These factors are preventable, thus permitting a possible reduction of the prevalence of these diseases.

Childhood environment and atopic conditions, with emphasis on asthma in a Chilean agricultural area

BACKGROUND

An explanation of the etiology of atopic conditions based on the hygiene hypothesis remains controversial.

OBJECTIVE

To analyze exposure variables in childhood to assess their impact on hay fever, asthma, and sensitization.

METHODS

Data were collected on 1,232 young Chilean adults born between 1974 and 1978. Information was available on consultations for infections early in life, number of siblings, sharing a bedroom, nursery school attendance, and contact with animals in the first 5 years of life. Information on asthma symptoms and rhinitis were obtained from a standardized questionnaire. Sensitization to eight allergens and bronchial hyper responsiveness (BHR) to methacholine were assessed. The study design was non-concurrent longitudinal for infectious episodes and nutritional status in the first year and cross-sectional for the other outcomes.

RESULTS

Number of siblings was associated with sensitization only (p = 0.0048). Nursery school attendance was negatively associated with positive BHR (odds ratio (OR) 0.54, 95% CI 0.30-0.95). A severe respiratory infection early in life was protective of sensitization and wheeze combined (OR 0.29, 95%CI 0.12-0.74). Contact with dogs in the first year was a protective factor of rhinitis (OR 0.47, 95%CI 0.28-0.80), but contact with poultry and cats early in life increased the risk of rhinitis (OR 1.42, 95%CI 1.06-1.88; 1.82, 95%CI 1.06-3.14).

CONCLUSION

The pattern of associations between environmental exposure in early life and atopic conditions was inconsistent. The significant associations were evenly distributed as protective and risk factors of atopic conditions.

The role of economic and educational factors in asthma: evidence from the Portuguese health survey

OBJECTIVE

To evaluate the importance of economic and educational factors in determining the risk of asthma in adults.

STUDY DESIGN AND METHODS

This was a cross-sectional study in a representative sample of Portuguese adults (20,977 females and 18,663 males) from the main regions of mainland Portugal. Participants were categorized according to years of education (< or = 4, 5-9, 10-12 and >12 years) and income (< or = 314, 315-547, 548-815 and >815Euros/month). Information on asthma was based on answers to the following question: 'Have you had asthma in the previous year?' Logistic regression models were fitted to estimate the magnitude of the association between asthma and education/income, adjusting for confounders (body mass index, age, smoking habits, physical activity, area of residence, number of household members and income/education).

RESULTS

In females and males, the odds of having asthma decreased with increasing income (P-value for trend <0.001), with odds ratios of 0.52 [95% confidence intervals (CI) 0.41-0.66] and 0.55 (95%CI 0.44-0.68) for those with a monthly income >815 Euros compared with those with a monthly income 314 Euros, respectively. For both genders, the odds of having asthma were not significantly associated with years of education.

CONCLUSION

A significant positive association between per capita national income and asthma reinforces that public policy should stress the importance of economic growth as a means for preventing asthma occurrence and improving quality of life.

Distinctive immunoglobulin E anti-house dust allergen-binding specificities in a tropical Australian Aboriginal community

BACKGROUND

There is evidence that the specificity of the IgE binding in allergy tests can vary for different populations.

OBJECTIVE

We aimed to examine the allergenic specificity of IgE binding in sera from house dust mite (HDM)-atopic subjects in a tropical Australian Aboriginal community.

METHODS

Sera shown to contain IgE antibodies to an HDM extract of Dermatophagoides pteronyssinus were examined for IgE binding to a panel of nine purified HDM allergens from this mite species by quantitative microtitre assays. IgG antibody binding (IgG1 and IgG4) was also measured.

RESULTS

The IgE-binding activity in the sera from the Aboriginal community was not directed to the expected major groups 1 and 2 HDM allergens but instead to the group 4 amylase allergen. There was also little IgE binding to the potentially cross-reactive tropomyosin (Der p 10) or arginine kinase (Der p 20) allergens. The IgG4 antibody was rarely detected and limited to the Der p 4 allergen. IgG1 antibody binding was frequently measured to all the allergens regardless of an individual's atopic status, whereas in urban communities it is restricted to the major allergens and to atopic subjects.

CONCLUSION

The high IgE anti-HDM response of Australian Aboriginals predominantly bound Der p 4 and not the Der p 1 and 2 allergens, showing a distinctive allergy that could affect the disease outcome and diagnosis.

Indoor risk factors for cough and their relation to wheeze and sensitization in Chilean young adults

OBJECTIVES

We assessed the effects of indoor risk factors, including smoking, on different types of cough and on cough and wheeze in combination.

METHODS

Our sample was composed of 1232 men and women residing in a semirural area of Chile. We used a standardized questionnaire, sensitization to 8 allergens, and bronchial hyperresponsiveness to methacholine to assess cough and wheeze characteristics. Information was gathered on dampness, mold, ventilation, heating, housing quality, smoking, and environmental tobacco smoke exposure.

RESULTS

Most exposures were associated with cough alone or cough in combination with wheeze. Smoking, past smoking, and environmental tobacco smoke exposure were strongly associated with dry cough and wheeze. The use of coal for heating was associated with dry cough. Leaks, mold, and lack of kitchen ventilation were associated with cough and wheeze. Nocturnal cough and productive cough were associated with specific types of sensitization, but dry cough was not. Productive cough was associated with hyperresponsiveness to methacholine.

CONCLUSIONS

Several different types of indoor exposures, including environmental tobacco smoke exposure, are important contributors to morbidity associated with cough and wheeze. A vigorous preventive strategy designed to lower exposures to indoor risk factors would lower rates of respiratory morbidity.

Prevalence and risk factors for work related asthma in young adults

OBJECTIVES

To investigate the prevalence and predictors of work related asthma in young adults from the general population.

METHODS

A total of 1922 subjects randomly selected from a birth cohort 1978/79 in Brazil, aged 23-25 years, completed a respiratory symptoms questionnaire based on the European Community Respiratory Health Survey, and underwent spirometry, bronchial challenge test with methacholine, and skin prick test. For subjects presenting with bronchial hyperresponsiveness, workplace exposure and its relationship with symptoms were assessed by a specific questionnaire and individualised job description to define cases of work related asthma.

RESULTS

The prevalence of work related asthma was 4.2% (81 cases): 1.5% (29 cases) were classified as aggravated asthma and 2.7% (52 cases) as occupational asthma. Work related asthma was associated with atopy and education. Lower educational level (1-8 years of schooling) was associated with work related asthma (odds ratio 7.06, 95% CI 3.25 to 15.33). There was no association between work related asthma and smoking, gender, or symptoms of rhinitis.

CONCLUSION

The prevalence of work related asthma was high (4.2%), and was associated with low schooling, probably because of low socioeconomic level. The disease may therefore be a consequence of poverty.

Agreement between responses to a standardized asthma questionnaire and a questionnaire following a demonstration of asthma symptoms in adults

Asthma epidemiology relies heavily on standardized questionnaires, but little is known about the understanding of asthma symptoms among adults in the community. In 2004, the authors assessed the level of agreement between responses to a standardized questionnaire and responses to a questionnaire completed by participants after viewing a demonstration of asthma symptoms. The study involved 601 young adults from Chile. The field-workers were trained to explain and demonstrate the asthma symptoms to the participants. The symptoms were wheeze, waking at night with breathlessness, breathlessness following exercise, and waking with cough. The kappa statistic did not exceed 0.4, and the recorded prevalence of asthma symptoms following the demonstration was 30-60% lower than that for the standardized questionnaire. Using bronchial responsiveness as the proxy gold standard, the positive likelihood ratios for wheeze and waking short of breath were higher following symptom demonstration. The low agreement between the standardized questionnaire and the postdemonstration questionnaire and the likelihood ratios' closeness to 1 for the standardized questionnaire decreases the authors' confidence in the appropriateness of this tool for estimating the prevalence of asthma in the community. For etiologic studies of asthma, it may contribute to the lack of consistency between different studies analyzing the same etiologic exposures.