Asthma incidence and risk factors in a national longitudinal sample of adolescent Canadians: a prospective cohort study

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

The frequency of sleep-disordered breathing in preschool children with asthma and its effects on control of asthma

CONCLUSION

The frequency and score of SDB were higher in patients with uncontrolled asthma. Frequency and score of SDB were significantly affected by the severity of asthma. SDB must be evaluated in preschool children with uncontrolled asthma.

CONCLUSION

Sleep-disordered breathing (SDB) is more common in asthmatic patients than in non-asthmatic persons, and SDB affects negatively to control asthma. A limited number of studies are discovered on the effect of SDB in preschool asthmatic children. In this study, we aimed to investigate the prevalence of SDB and its effect on control and severity of asthma in preschool children. A pediatric sleep questionnaire was completed by parents of asthmatic children. Patients who received a score of 0.33 or higher were diagnosed with SDB. Control and severity of asthma was assessed by a pediatric allergy specialist based on the Global Initiative for Asthma (GINA) criteria. The study included 249 patients, with a mean±SD age of 4.37±1.04 (range: 2-5.9) years; 69% were boys; 56.6% children had uncontrolled asthma and 28.7% had SDB. The SDB score was significantly different between controlled and uncontrolled asthma (0.19 vs 0.28; P < 0.001). The frequency of uncontrolled asthma in patients with and without SDB was 74.3% and 49.4%, respectively (P < 0.010). Based on the severity of asthma, the frequency of SDB among patients with mild, moderate, and severe asthma was 23.4%, 35.2%, and 47.4%, respectively (P = 0.010).

Geographical Differences of Risk of Asthma and Allergic Rhinitis according to Urban/Rural Area: a Systematic Review and Meta-analysis of Cohort Studies

Several studies have demonstrated an association between the risk asthma/allergic rhinitis and the environment. However, to date, no systematic review or meta-analysis has investigated these factors. We conducted a systematic review and meta-analysis to assess the association between urban/rural living and the risk of asthma and allergic rhinitis. We searched the Embase and Medline databases for relevant articles and included only cohort studies to observe the effects of time-lapse geographical differences. Papers containing information on rural/urban residence and respiratory allergic diseases were eligible for inclusion. We calculated the relative risk (RR) and 95% confidence interval (CI) using a 2 × 2 contingency table and used random effects to pool data. Our database search yielded 8388 records, of which 14 studies involving 50,100,913 participants were finally included. The risk of asthma was higher in urban areas compared to rural areas (RR, 1.27; 95% CI, 1.12-1.44, p < 0.001), but not for the risk of allergic rhinitis (RR, 1.17; 95% CI, 0.87-1.59, p = 0.30). The risk of asthma in urban areas compared to rural areas was higher in the 0-6 years and 0-18 years age groups, with RRs of 1.21 (95% CI, 1.01-1.46, p = 0.04) and 1.35 (95% CI, 1.12-1.63, p = 0.002), respectively. However, there was no significant difference in the risk of asthma between urban and rural areas for children aged 0-2 years, with a RR of 3.10 (95% CI, 0.44-21.56, p = 0.25). Our study provides epidemiological evidence for an association between allergic respiratory diseases, especially asthma, and urban/rural living. Future research should focus on identifying the factors associated with asthma in children living in urban areas. The review was registered in PROSPERO (CRD42021249578).

Retrospective cross-sectional study of asthma severity in adult patients at the Jimma Medical Center, Ethiopia

Asthma is one of the most prevalent chronic diseases and is a public health problem worldwide. It is a long-standing condition affecting the respiratory system. Thus this study aimed to assess the severity of asthma in patients at the adult emergency department of Jimma Medical Center (JMC), Southwest Ethiopia. A one year (1 May, 2020, to 1 May, 2021) retrospective cross-sectional study was conducted among 189 patients at the adult emergency department of JMC. Data were collected between 25 July, 2021 to 25 August, 2021 by two Bachelor of Science degree holders in nursing (BSC) nurses after providing proper training. We used structured checklist that was obtained from previous studies to collect the data. Finally, data were entered into EpiData version 3.1 then exported to Stata version 15.0 for further analysis. Multinomial analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association between risk factors and severity of asthma. Of 195 patients retrieved from the Health management information system (HMIS) logbook and patient profile, 189 fulfilled the eligibility criteria giving a response rate of 96.9%. The mean age of patients was 47.69 (± 19.02) years old ranging from 20 to 85. More than one third of the patients were age range of 20-39 years. Only more than half of the patients were women. Almost 46% of the patients had moderate asthma. Being male, merchant and government employees had lower odds of asthma than their counterparts whereas being daily laborers and smoking contributed to increased odds of moderate asthma. Patients' age and comorbidities had increased odds of severe asthma in relation to the participants of their reference category. Urban residents had decreased odds of severe asthma compared to their rural counterparts. This study highlights that majority of patients had moderate asthma. Health care providers should pay special attention to accurately diagnosing asthma according to its severity which is essential to the optimal management of asthma. This study calls JMC health care providers to give due attention while providing routine care for their patients in accordance to identified factors.

Perceptions towards childhood asthma and barriers to its management among patients, caregivers and healthcare providers: a qualitative study from Ethiopia

Background

The management of asthma, which is one of the major causes of childhood morbidity and mortality has been affected by non-adherence to recommended treatment regimens with severe consequences. The aim of the present study was therefore to explore the perceptions of the children with asthma, their caregivers and their healthcare providers towards asthma and barriers to long term childhood asthma management in an institutional setting in Addis Ababa, Ethiopia.

Methods

A qualitative descriptive design was followed for the present study that used individual interviews as a data collection method. The study participants were 23 pairs of children with asthma that had treatment follow-ups in two tertiary hospitals and their caregivers and eight healthcare providers who cared for these children. The data was analyzed using thematic analysis approach.

Results

The study findings revealed that the children’s reported adherence to the recommended treatment regimens was low and they along with their caregivers were facing physical, emotional and social burdens related to asthma. Some of the influencing factors affecting childhood asthma management were found to be the low-level implementation of the asthma management guidelines by the healthcare providers, limited awareness about asthma and its management by the children and their caregivers, use of traditional home remedies and religious healing on a complementary and alternative basis and inadequate education received from healthcare professionals. Further identified barriers to the adherence of especially inhaled corticosteroids appear to be the low necessity beliefs towards chronic administration of treatment regimens and concerns related with difficulty of administration, fear of side effects and general negative attitude towards it, in addition to their low availability and affordability.

Conclusions

Low awareness of the biomedical treatment regimens and use of traditional home remedies and religious healing by the children with asthma and their caregivers, the low-level implementation of the asthma management guidelines as well as low access to medications may among other things contribute to the low adherence of the children to their recommended regimens. The findings support the need for implementation of asthma management guidelines, institution of strong asthma care and education programs that are sensitive to local and individual patients’ and caregiver perceptions and experiences including emotional distress, the need to institute chronic care approach and ways to address patients’ medication access issues.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01984-2.

Pediatric asthma incidence rates in the United States from 1980 to 2017

BACKGROUND

Few studies have examined longitudinal asthma incidence rates (IRs) from a public health surveillance perspective.

OBJECTIVE

Our aim was to calculate descriptive asthma IRs in children over time with consideration for demographics and parental asthma history.

METHODS

Data from 9 US birth cohorts were pooled into 1 population covering the period from 1980 to 2017. The outcome was earliest parental report of a doctor diagnosis of asthma. IRs per 1,000 person-years were calculated.

RESULTS

The racial/ethnic backgrounds of the 6,283 children studied were as follows: 55% European American (EA), 25.5% African American (AA), 9.5% Mexican-Hispanic American (MA) and 8.5% Caribbean-Hispanic American (CA). The average follow-up was 10.4 years (SD = 8.5 years; median = 8.4 years), totaling 65,291 person-years, with 1789 asthma diagnoses yielding a crude IR of 27.5 per 1,000 person-years (95% CI = 26.3-28.8). Age-specific rates were highest among children aged 0 to 4 years, notably from 1995 to 1999, with a decline in EA and MA children in 2000 to 2004 followed by a decline in AA and CA children in 2010 to 2014. Parental asthma history was associated with statistically significantly increased rates. IRs were similar and higher in AA and CA children versus lower but similar in EA and MA children. The differential rates by sex from birth through adolescence principally resulted from a decline in rates among males but relatively stable rates among females.

CONCLUSIONS

US childhood asthma IRs varied dramatically by age, sex, parental asthma history, race/ethnicity, and calendar year. Higher rates in the 0- to 4-year-olds group, particularly among AA/CA males with a parental history of asthma, as well as changes in rates over time and by demographic factors, suggest that asthma is driven by complex interactions between genetic susceptibility and variation in time-dependent environmental and social factors.

US Childhood Asthma Incidence Rate Patterns From the ECHO Consortium to Identify High-risk Groups for Primary Prevention

Importance

Asthma is the leading chronic illness in US children, but most descriptive epidemiological data are focused on prevalence.

Objective

To evaluate childhood asthma incidence rates across the nation by core demographic strata and parental history of asthma.

Design, Setting, and Participants

For this cohort study, a distributed meta-analysis was conducted within the Environmental Influences on Child Health Outcomes (ECHO) consortium for data collected from May 1, 1980, through March 31, 2018. Birth cohort data of children from 34 gestational weeks of age or older to 18 years of age from 31 cohorts in the ECHO consortium were included. Data were analyzed from June 14, 2018, to February 18, 2020.

Exposures

Caregiver report of physician-diagnosed asthma with age of diagnosis.

Main Outcome and Measures

Asthma incidence survival tables generated by each cohort were combined for each year of age using the Kaplan-Meier method. Age-specific incidence rates for each stratum and asthma incidence rate ratios by parental family history (FH), sex, and race/ethnicity were calculated.

Results

Of the 11 404 children (mean [SD] age, 10.0 [0.7] years; 5836 boys [51%]; 5909 White children [53%]) included in the primary analysis, 7326 children (64%) had no FH of asthma, 4078 (36%) had an FH of asthma, and 2494 (23%) were non-Hispanic Black children. Children with an FH had a nearly 2-fold higher incidence rate through the fourth year of life (incidence rate ratio [IRR], 1.94; 95% CI, 1.76-2.16) after which the rates converged with the non-FH group. Regardless of FH, asthma incidence rates among non-Hispanic Black children were markedly higher than those of non-Hispanic White children during the preschool years (IRR, 1.58; 95% CI, 1.31-1.86) with no FH at age 4 years and became lower than that of White children after age 9 to 10 years (IRR, 0.67; 95% CI, 0.50-0.89) with no FH. The rates for boys declined with age, whereas rates among girls were relatively steady across all ages, particularly among those without an FH of asthma.

Conclusions and Relevance

Analysis of these diverse birth cohorts suggests that asthma FH, as well as race/ethnicity and sex, were all associated with childhood asthma incidence rates. Black children had much higher incidences rates but only during the preschool years, irrespective of FH. To prevent asthma among children with an FH of asthma or among Black infants, results suggest that interventions should be developed to target early life.

Health Disparities in Environmental and Occupational Lung Disease

Pulmonary health disparities disproportionately impact disadvantaged and vulnerable populations. This article focuses on disparities in disease prevalence, morbidity, and mortality for asthma, chronic obstructive pulmonary disease, pneumoconiosis, and lung cancer. Disparities are categorized by race, age, sex, socioeconomic status, and geographic region. Each category highlights differences in risk factors for the development and severity of lung disease. Risk factors include social, behavioral, economic, and biologic determinants of health (occupational/environmental exposures, psychosocial stressors, smoking, health literacy, health care provider bias, and health care access). Many of these risk factors are complex and inter-related; strategies proposed to decrease disparities require multilevel approaches.

Contributing Factors for Underutilization of Inhaled Corticosteroids Among Asthmatic Patients Attending at Adama Hospital Medical College, Adama, Ethiopia

INTRODUCTION

Inhaled corticosteroids (ICSs) are a cornerstone medicine for preventive therapy of persistent severe asthma. Although ICs are very effective for the treatment of severe persistent asthma, the majority of the prescribers worldwide aren't aware of ICs use for the treatment of severe persistent asthma.

OBJECTIVE

To evaluate factors contributing to underutilization of ICS by asthmatic patients.

METHODS

Patient interview was conducted among asthmatic patients using a cross-sectional study design who were attending at the Adama Hospital Medical College from March 1 to July 25, 2017. The total number of patients involved in the study was 94. Semi-structured questionnaire through patient interview was used for data collection and data from physicians who were working at the chest clinic of AHMC were collected by self-administered semi-structured questionnaire focusing their perspectives and experiences on patients' ICS.

RESULTS

Generally 73.5% of underutilization of ICS was reported from the total number of patients involved in the study according to the patient's perception. Monthly income, comorbid disease, and behaviors of ICS use were the main factors contributing to underutilization of ICS. According to patient's report, some of the reasons for underutilization of ICS were unaffordability, using the drugs only when symptoms appear, inaccessibility, side effects and recommendation by physicians. There were also similar reports by the physicians working in the AHMC.

CONCLUSION

In our study setting, prevalence of underutilization of ICS was high and the contributing factors were increased cost of ICS, inaccessibility of ICS, poor knowledge of the patients on asthma disease and ICS, bad attitude toward ICS, and lack of recently reviewed local guideline for asthma treatment. Thus, concerned experts need to take actions that guarantee accessibility of ICS at a reasonable price and increase awareness of patients about asthma disease and use of ICS.

Sleep duration patterns from adolescence to young adulthood and the risk of asthma

PURPOSE

This study examined the association between sleep duration trajectories from adolescence to young adulthood and the risk of asthma into young adulthood.

METHODS

Using data from 10,362 participants in the National Longitudinal Study of Adolescent to Adult Health (Add Health) free of asthma at baseline, we constructed trajectories of sleep duration from adolescence (age 13-18 years) to young adulthood (age 24-32 years) and used them to examine the association between sleep duration patterns and the risk of new-onset asthma using a log-binomial regression model after adjusting for potential confounders.

RESULTS

The results revealed that 14.4% of nonasthmatic participants had persistent short sleep duration, whereas 80.0% had adequate sleep duration from adolescence through young adulthood. Consistently short-sleepers had 1.52 times the risk of new-onset asthma by age 32 years (95% CI 1.11, 2.10) compared with consistently adequate sleepers. The association was stronger in those with a family history of asthma (aRR = 2.43, 95% CI 1.15, 5.13) than in those without such history (aRR = 1.43, 95% CI 1.05, 1.95).

CONCLUSIONS

We conclude that persistent short sleep duration is associated with an increased risk of new-onset asthma in young adults. This association may be more pronounced among those at high risk of asthma because of family history.

Sex-specific incidence of asthma, rhinitis and respiratory multimorbidity before and after puberty onset: individual participant meta-analysis of five birth cohorts collaborating in MeDALL

Introduction

To understand the puberty-related sex shift in the prevalence of asthma and rhinitis as single entities and as respiratory multimorbidities, we investigated if there is also a sex-specific and puberty-related pattern of their incidences.

Methods

We used harmonised questionnaire data from 18 451 participants in five prospective observational European birth cohorts within the collaborative MeDALL (Mechanisms of the Development of Allergy) project. Outcome definitions for IgE-associated and non-IgE-associated asthma, rhinitis and respiratory multimorbidity (first occurrence of coexisting asthma and rhinitis) were based on questionnaires and the presence of specific antibodies (IgE) against common allergens in serum. For each outcome, we used proportional hazard models with sex–puberty interaction terms and conducted a one-stage individual participant data meta-analysis.

Results

Girls had a lower risk of incident asthma (adjusted HR 0.67, 95% CI 0.61 to 0.74), rhinitis (0.73, 0.69 to 0.78) and respiratory multimorbidity (0.58, 0.51 to 0.66) before puberty compared with boys. After puberty onset, these incidences became more balanced across the sexes (asthma 0.84, 0.64 to 1.10; rhinitis 0.90, 0.80 to 1.02; respiratory multimorbidity 0.84, 0.63 to 1.13). The incidence sex shift was slightly more distinct for non-IgE-associated respiratory diseases (asthma 0.74, 0.63 to 0.87 before vs 1.23, 0.75 to 2.00 after puberty onset; rhinitis 0.88, 0.79 to 0.98 vs 1.20, 0.98 to 1.47; respiratory multimorbidity 0.66, 0.49 to 0.88 vs 0.96, 0.54 to 1.71) than for IgE-associated respiratory diseases.

Discussion

We found an incidence ‘sex shift’ in chronic respiratory diseases from a male predominance before puberty to a more sex-balanced incidence after puberty onset, which may partly explain the previously reported sex shift in prevalence. These differences need to be considered in public health to enable effective diagnoses and timely treatment in adolescent girls.

Changes in the prevalence of asthma and related risk factors in adolescents: Three surveys between 1994 and 2015

METHODS

This study assesses the temporal trend of current asthma symptoms prevalence and associated factors in Chilean adolescents from South-Santiago, considering surveys performed in 1994, 2002 and 2015.

RESULTS

The prevalence of current asthma symptoms showed a trend to increase from 11.1% in 1994 to 13.4% in 2015 (p<0.001); physician-diagnosed asthma increased from 11.5% to 13.8%, (p<0.001) whereas severe asthma and asthma with exercise decreased (p<0.001). Female adolescents had a higher prevalence of current asthma in the three surveys (p<0.001), and was a risk factor for asthma in the three surveys. In 2002, frequent consumption of meat and potatoes were associated with current asthma while frequent vigorous exercise was protective. Frequent exercise and parental tobacco smoking were risk for asthma in 2015 (p<0.001). Current active tobacco smoking showed a trend to increase reaching a prevalence of 28.9% in 2015 (p<0.001). There was a consistently low proportion of adolescents with current wheezing and asthma diagnosis (32.1% in 2015) and 37.6% of them had no asthma treatment.

CONCLUSION

The prevalence of current asthma in adolescents from the studied area would be still increasing. As in other studies, female adolescents had a higher prevalence of current asthma. Current active tobacco smoking has strikingly increased in the studied children while indoor passive tobacco exposure remains inadmissibly high. Our findings suggest that asthma in children is underdiagnosed and undertreated. More attention should be given to female gender, tobacco exposure, air pollution and local diagnostic preferences when studying and interpreting trends of asthma prevalence in adolescents from developing localities.

Lies, damned lies and statistics: Clinical importance versus statistical significance in research

Correctly performed and interpreted statistics play a crucial role for both those who 'produce' clinical research, and for those who 'consume' this research. Unfortunately, however, there are many misunderstandings and misinterpretations of statistics by both groups. In particular, there is a widespread lack of appreciation for the severe limitations with p values. This is a particular problem with small sample sizes and low event rates - common features of many published clinical trials. These issues have resulted in increasing numbers of false positive clinical trials (false 'discoveries'), and the well-publicised inability to replicate many of the findings. While chance clearly plays a role in these errors, many more are due to either poorly performed or badly misinterpreted statistics. Consequently, it is essential that whenever p values appear, these need be accompanied by both 95% confidence limits and effect sizes. These will enable readers to immediately assess the plausible range of results, and whether or not the effect is clinically meaningful.

Lay-led and peer support interventions for adolescents with asthma

BACKGROUND

Adolescents with asthma are at high risk of poor adherence with treatment. This may be compounded by activities that worsen asthma, in particular smoking. Additional support above and beyond routine care has the potential to encourage good self-management. We wanted to find out whether sessions led by their peers or by lay leaders help to reduce these risks and improve asthma outcomes among adolescents.

OBJECTIVES

To assess the safety and efficacy of lay-led and peer support interventions for adolescents with asthma.

SEARCH METHODS

We identified trials from the Cochrane Airways Trials Register, which contains reports of randomised trials obtained from multiple electronic and handsearched sources, and we searched trial registries and reference lists of primary studies. We conducted the most recent searches on 25 November 2016.

SELECTION CRITERIA

Eligible studies randomised adolescents with asthma to an intervention led by lay people or peers or to a control. We included parallel randomised controlled trials with individual or cluster designs. We included studies reported as full text, those published as abstract only and unpublished data.

DATA COLLECTION AND ANALYSIS

Two review authors screened the searches, extracted numerical data and study characteristics and assessed each included study for risk of bias. Primary outcomes were asthma-related quality of life and exacerbations requiring at least a course of oral steroids. We graded the analyses and presented evidence in a 'Summary of findings' table.We analysed dichotomous data as odds ratios, and continuous data as mean differences (MD) or standardised mean differences, all with a random-effects model. We assessed clinical, methodological and statistical heterogeneity when performing meta-analyses, and we described skewed data narratively.

MAIN RESULTS

Five studies including a total of 1146 participants met the inclusion criteria for this review. As ever with systematic reviews of complex interventions, studies varied by design (cluster and individually randomised), duration (2.5 to 9 months), setting (school, day camp, primary care) and intervention content. Most risk of bias concerns were related to blinding and incomplete reporting, which limited the meta-analyses that could be performed. Studies generally controlled well for selection and attrition biases.All participants were between 11 and 17 years of age. Asthma diagnosis and severity varied, as did smoking prevalence. Three studies used the Triple A programme; one of these studies tested the addition of a smoke-free pledge; another delivered peer support group sessions and mp3 messaging to encourage adherence; and the third compared a peer-led asthma day camp with an equivalent camp led by healthcare practitioners.We had low confidence in all findings owing to risk of bias, inconsistency and imprecision. Results from an analysis of asthma-related quality of life based on the prespecified random-effects model were imprecise and showed no differences (MD 0.40, 95% confidence interval (CI) -0.02 to 0.81); a sensitivity analysis based on a fixed-effect model and a responder analysis suggested small benefit may be derived for this outcome. Most other results were summarised narratively and did not show an important benefit of the intervention; studies provided no analysable data on asthma exacerbations or unscheduled visits (data were skewed), and one study measuring adherence reported a drop in both groups. Effects on asthma control favoured the intervention but findings were not statistically significant. Results from two studies with high levels of baseline smoking showed some promise for self-efficacy to stop smoking, but overall nicotine dependence and smoking-related knowledge were not significantly better in the intervention group. Investigators did not report adverse events.

AUTHORS' CONCLUSIONS

Although weak evidence suggests that lay-led and peer support interventions could lead to a small improvement in asthma-related quality of life for adolescents, benefits for asthma control, exacerbations and medication adherence remain unproven. Current evidence is insufficient to reveal whether routine use of lay-led or peer support programmes is beneficial for adolescents receiving asthma care.Ongoing and future research may help to identify target populations for lay-led and peer support interventions, along with attributes that constitute a successful programme.

Lifetime secondhand smoke exposure and childhood and adolescent asthma: findings from the PIAMA cohort

BACKGROUND

Secondhand smoke (SHS) exposure is a modifiable risk factor associated with childhood asthma. Associations with adolescent asthma and the relevance of the timing and patterns of exposure are unclear. Knowledge of critical windows of exposure is important for targeted interventions.

METHODS

We used data until age 17 from 1454 children of the Dutch population-based PIAMA birth cohort. Residential SHS exposure was assessed through parental questionnaires completed at ages 3 months, 1-8 (yearly), 11, 14, and 17 years. Lifetime exposure was determined as; a) time window-specific exposure (prenatal, infancy, preschool, primary school, and secondary school); b) lifetime cumulative exposure; c) longitudinal exposure patterns using latent class growth modeling (LCGM). Generalized estimation equations and logistic regression were used to analyze associations between exposure and asthma at ages 4 to 17 years, adjusting for potential confounders.

RESULTS

With all three methods, we consistently found no association between SHS exposure and asthma at ages 4 to 17 years e.g. adjusted overall odds ratio (95% confidence interval) 0.67 (0.41-1.12), 1.00 (0.66-1.51) and 0.67 (0.41-1.11) for prenatal maternal active smoking, infancy, and preschool school time window exposures, respectively.

CONCLUSION

We assessed lifetime SHS exposure using different methods. Different timing and patterns of SHS exposure were not associated with an increased risk of asthma in childhood and adolescence in our study. More longitudinal studies could investigate effects of lifetime SHS exposure on asthma in adolescence and later life.

The Danish National Database for Asthma: establishing clinical quality indicators

Asthma is one of the most common chronic diseases worldwide affecting more than 300 million people. Symptoms are often non-specific and include coughing, wheezing, chest tightness, and shortness of breath. Asthma may be highly variable within the same individual over time. Although asthma results in death only in extreme cases, the disease is associated with significant morbidity, reduced quality of life, increased absenteeism, and large costs for society. Asthma can be diagnosed based on report of characteristic symptoms and/or the use of several different diagnostic tests. However, there is currently no gold standard for making a diagnosis, and some degree of misclassification and inter-observer variation can be expected. This may lead to local and regional differences in the treatment, monitoring, and follow-up of the patients. The Danish National Database for Asthma (DNDA) is slated to be established with the overall aim of collecting data on all patients treated for asthma in Denmark and systematically monitoring the treatment quality and disease management in both primary and secondary care facilities across the country. The DNDA links information from population-based disease registers in Denmark, including the National Patient Register, the National Prescription Registry, and the National Health Insurance Services register, and potentially includes all asthma patients in Denmark. The following quality indicators have been selected to monitor trends: first, conduction of annual asthma control visits, appropriate pharmacological treatment, measurement of lung function, and asthma challenge testing; second, tools used for diagnosis in new cases; and third, annual assessment of smoking status, height, and weight measurements, and the proportion of patients with acute hospital treatment. The DNDA will be launched in 2016 and will initially include patients treated in secondary care facilities in Denmark. In the nearby future, the database aims to include asthma diagnosis codes and clinical data registered by general practitioners and specialised practitioners as well.

Asthma transition from childhood into adulthood

Asthma is the most prevalent chronic respiratory disease both in children and adults and resembles a complex syndrome rather than a single disease. Different methods have been developed to better characterise distinct asthma phenotypes in childhood and adulthood. In studies of adults, most phenotyping relies on biomaterials from the lower airways; however, this information is missing in paediatric studies because of restricted accessibility. Few patients show symptoms throughout childhood, adolescence, and adulthood. Risk factors for this might be genetics, family history of asthma and atopy, infections early in life, allergic diseases, and lung function deficits. In turn, a large proportion of children with asthma lose their symptoms during school age and adolescence. This improved prognosis, which might also reflect a better treatment response, is associated with being male and with milder and less allergic disease. Importantly, whether clinical remission of symptoms equals the disappearance of underlying pathology is unknown. In fact, airway hyper-responsiveness and airway inflammation might remain despite the absence of overt symptoms. Additionally, a new-onset of asthma symptoms is apparent in adulthood, especially in women and in the case of impaired lung function. However, many patients do not remember childhood symptoms, which might reflect relapse rather than true initiation. Both relapse and adult-onset of asthma symptoms have been associated with allergic disease and sensitisation in addition to airway hyper-responsiveness. Thus, asthma symptoms beginning in adults might have originated in childhood. Equivocally, persistence into, relapse, and new-onset of symptoms in adulthood have all been related to active smoking. However, underlying mechanisms for the associations remain unclear, and future asthma research should therefore integrate standardised molecular approaches in identical ways in both paediatric and adult populations and in longitudinal studies.

Association of living in a farming environment with asthma incidence in Canadian children

OBJECTIVE

The objective of this population-based 14-year follow-up study was to examine the effect of living in a farm environment on asthma incidence in children.

METHODS

A total of 10,941 children of ages 0 to 11 years who were free of asthma and wheeze at the baseline (1994-1995) in the National Longitudinal Survey of Children and Youth were considered in the study. Children's living environment was classified, based on interviewer's observation, into three categories: non-rural, rural non-farming, and farming. An incidence of asthma was obtained from health-professional diagnosed asthma reported either by the person most knowledgeable for children under 15 years or by the children themselves if they were of ages 16 years and over.

RESULTS

The 14-year cumulative incidence of asthma among children living in farming environments was 10.18%, which was significantly lower than that observed for children living in rural non-farming (13.12%) and non-rural environments (16.50%). After adjusting for age group, number of older siblings, allergy, parental history of asthma, dwelling in need of repairs and SES index, a dose-response relationship was observed with children living in rural non-farming and farming environments having significantly reduced risk of asthma [hazard ratio (HR): 0.77; 95% confidence interval (CI): (0.60, 1.00); p = 0.047 and HR: 0.56; 95% CI: (0.41,0.77); p < 0.001] in comparison to those living in non-rural environments.

CONCLUSION

This cohort study provides further evidence that living in a farming environment during childhood is protective of asthma incidence in adolescence and adulthood and this finding provides further support for the hygiene hypothesis.

Asthma prevalence and risk factors in early childhood at Northern Portugal

Asthma is the commonest and most important chronic non-infectious disease in childhood and it has become more prevalent in recent years. There is a shortage of studies in relation to early childhood and so, as part of the INAIRCHILD project, this cross-sectional study aimed to assess the prevalence of asthma and its associated risk factors, namely demographic, environmental, psychosocial and clinical factors for infants and preschoolers living in Northern Portugal. Data concerning asthma prevalence were collected through questionnaires based on those from the International Study of Asthma and Allergies in Childhood (ISAAC-derived), the questionnaires were distributed to 1042 children attending the 17 nurseries involved in the INAIRCHILD project (10 in urban and suburban context, and 7 in rural context). The response rate was 48%. Prevalence of asthma based on symptomatology and odds ratio was calculated. Around 52% of the studied children presented at least one of the respiratory symptoms investigated (wheeze, dyspnea and cough) in the absence of upper respiratory infections. The prevalence of asthma was 10.7%, comparable to the figures for Portuguese schoolchildren (6-7 years old) reported by the national Directorate-General of Health, thus showing that an early diagnosis might be possible and helpful for the mitigation of childhood asthma. Environmental context (urban, suburban or rural), gender and family asthma history showed clear associations with asthma prevalence, namely non-rural location, male gender, and having an asthmatic parent were found to be risk factors.

Obesity, low levels of physical activity and smoking present opportunities for primary care asthma interventions: an analysis of baseline data from The Asthma Tools Study

BACKGROUND

Asthma prevalence, severity and outcomes are associated with various patient characteristics and lifestyle choices.

AIMS

To identify potentially modifiable factors associated with poor asthma outcomes among US primary care patients.

METHODS

Using baseline data from the Asthma Tools Study, we calculated cross-sectional frequencies of activity levels, smoking, secondhand smoke exposure and the presence of obesity, as well as rates of out-of-control asthma and asthma exacerbations. Frequencies were stratified by sex, and into three age groups: 5-11 years, 12-18 years and 19 years and older. Logistic regression was used to identify factors associated with each of the asthma outcomes.

RESULTS

In the 901 individuals enrolled in this asthma study, tobacco smoke exposure, obesity, low activity levels, poverty, inadequately controlled asthma and high asthma-related health-care utilisation were common. Across all age groups, obesity was associated with poorer asthma outcomes: either poor asthma control (odds ratio (OR)=2.3, 95% confidence interval (CI) 1.1-4.7 in 5- to 11-year-olds and OR=1.5, 95% CI 1.1-2.2 in adults) or asthma exacerbations (OR 2.9, 95% CI 1.6-5.1 in 12- to 18-year-olds and OR 1.7, 95% CI 1.1-2.5 in adults). Among adults, smoking was associated with both measures of poorer asthma outcomes; inadequate asthma control (OR=2.3, 95% CI 1.5-3.5), and asthma exacerbations (OR 1.7, 95% CI 1.1-2.6), and low physical activity were associated with poor asthma control (OR=1.5, 95% CI 1.1-2.2).

CONCLUSIONS

Obesity, low levels of physical activity and smoking are common, and they are associated with poor asthma outcomes in a sample of primary care patients, suggesting important targets for intervention.

Age-of-asthma onset as a determinant of different asthma phenotypes in adults: a systematic review and meta-analysis of the literature

Age-of-asthma onset is often used to distinguish different adult asthma phenotypes; however, similarities and differences between early- and late-onset adult asthma have not been summarized to date. Of the 2921 records found, we identified 12 studies comparing early- and late-onset current asthma in adults. Age 12 was most commonly used to delineate the two age-of-onset phenotypes. Adults with early-onset current asthma were more likely to be atopic and had a higher frequency of asthma attacks, whereas adults with late-onset disease were more likely to be female, smokers and had greater levels of spirometrically defined fixed airflow obstruction. The prevalence of severe asthma was similar in both groups, and, in general, there were few phenotypic differences between severe asthmatics regardless of age of onset. Findings for several key characteristics, including lung function, were inconsistent between studies. Overall, there appears to be distinctive phenotypic differences with age of asthma onset. Although early-onset adult asthma is likely more attributable to atopy and potentially genetic factors, late-onset adult asthma appears to be more related to environmental risk factors, and so may be better targeted by preventive strategies. More detailed research is required to better characterize these phenotypes and to clarify potential clinical implications.

The influence of childhood asthma on puberty and height in Swedish adolescents

BACKGROUND

Evidence relating to the effect of asthma on puberty or height is inconclusive. We aimed to examine whether the exposure of childhood asthma, including timing and phenotypes, and inhaled corticosteroid (ICS) use is either cross-sectionally or longitudinally associated with the outcomes of pubertal staging or height.

METHODS

This study employed data from a longitudinal, population-based cohort of Swedish children (born 1994-1996). At ages 1, 2, 4, 8, and 12 years, parent-reported data on asthma and ICS use in the previous 12 months were collected. At 8 and 12 years, height was ascertained at a clinical visit, and child-reported, respectively. At 12 years, children answered puberty-related questions.

RESULTS

Retention through 12 years was 82% (3366/4089). Participants without puberty data (n = 620) were excluded, yielding a study population of 2746 (67%). Asthma at 8 years, including timing of onset and phenotypes, was not statistically significantly associated with pubertal staging in adjusted models. Children with asthma averaged 0.93 cm (95% CI 0.35-1.50) shorter than children without asthma. Children with asthma using ICS were 1.28 (95% CI 0.62-1.95) shorter than those with asthma without using ICS.

CONCLUSIONS

We found no consistent association between asthma and pubertal staging. Children with asthma were shorter than those without asthma. Moreover, children with asthma using ICS were shorter than those not using ICS.

Increasing prevalence of asthma, respiratory symptoms, and allergic diseases: Four repeated surveys from 1993-2014

BACKGROUND

Published data shows different prevalence trends depending on the region of Europe.

AIM

The aim of the study was to analyze time trends of the frequency of the respiratory symptoms and allergic diseases in school children (Silesia, Poland) over the last 21 years.

METHODS

We compared the results of four population-based surveys performed in a town of Chorzow in 1993, 2002, 2007 and 2014 in children aged 7-10 years. All four studies had the same study protocol, recruitment (cluster, school-based sampling), questionnaire (WHO respiratory health questionnaire) and the same principal investigator The surveys included 1130 children in 1993, 1421 children in 2002, 1661 children in 2007 and 1698 in 2014.

RESULTS

The results covered a 21 year span and showed a statistically significant (p < 0.05) increase in the prevalence of the following physician-diagnosed disorders (1993-2002-2007-2014): asthma (3.4%-4.8%-8.6%-12,6%); allergic rhinitis (4.3%-11.9%-15.9%-13.9%); atopic dermatitis (3.6%-7.9%-12.0%-13.9%); allergic conjunctivitis (4.3%-7.9%-8.3%-7.9%); A simultaneous increasing trend (p < 0.05) in the attacks of dyspnea (3.9%-5.9%-7.0%-7.3%) and symptoms (wheeze, dyspnea, cough) induced by exercise (7.5%-10.6%-22.0%-22.4%) and - at the same time - decrease (p < 0.05) in the prevalence of cough (31.6%-19.6%15.4%-14.4%). Among children with diagnosed asthma during the 21 year span there was significantly (p < 0.05) increased proportion of treated children (51.3%-51.3%-69.5%-60.7%) and a lower frequency of presenting current symptoms.

CONCLUSIONS

Our findings are in line with the concept of a real increase in the occurrence of asthma and allergic disease in children. The pattern involves not only physician-diagnosed allergic diseases but also occurrence of symptoms related to respiratory disorders. Diagnosed asthma is better treated and better controlled.