A temporal decline in asthma but not eczema prevalence from 2000 to 2005 at school entry in the Australian Capital Territory with further consideration of country of birth

Prevalence and Associations of General Practice Registrars' Management of Atopic Dermatitis: A Cross-Sectional Analysis from the Registrar Clinical Encounters in Training Study

Introduction

Atopic dermatitis (AD) is a chronic inflammatory condition which imposes substantial burden upon patients and their families. As a frequent primary care presentation, general practice (GP) trainees must develop adequate skills in AD diagnosis and management.

Objectives

We aimed to explore the prevalence and associations of GP registrars' management of patients with AD.

Methods

This study used data from the Registrar Clinical Encounters in Training (ReCEnT) project, an ongoing cohort study of the clinical and educational experience of Australian GP registrars. Registrar, patient, and consultation factors were independent variables in multivariable logistic regression with outcome factor 'diagnosis/problem being AD'.

Results

From 2010-2019, 2,783 registrars (96% response rate) provided data from 381,180 consultations. AD was encountered in 0.6% of consults. AD was more likely to be seen in patients aged 0-1 years and patients from a non-English speaking background. AD was less likely to be seen in Aboriginal or Torres Strait Islander patients. Learning goals were more likely to be generated for AD and these consultations were associated with registrars seeking information or assistance. AD was strongly associated with a medication being prescribed, of which the most prescribed medications were mild or moderate potency topical corticosteroids.

Conclusions

Our findings suggest that, similar to other dermatological presentations, registrars find AD challenging to manage. There may be some gaps in AD management knowledge and application.

Smoking in the family is most predictive of the development of childhood asthma in preterm babies <30 weeks gestation: Results of the Respiratory Outcomes Study 2 (RESPOS2)

OBJECTIVES

The Respiratory Outcomes Study 2 (RESPOS2) investigated the relationship between neonatal outcomes (specifically, chronic lung disease [CLD]) and environmental factors on the development of asthma and atopic outcomes at primary school age for preterm babies (PBs) <30 weeks gestational age (GA).

METHODS

The study included all surviving PBs <30 weeks GA admitted to the Neonatal Intensive Care Unit at Canberra Hospital, Australian Capital Territory between 2007 and 2009. Parents were sent a questionnaire regarding asthma and atopy symptoms when the PBs were aged 5-7 years old. Data were compared based on CLD status.

RESULTS

There were 103 PBs included in the study with a 68.9% response rate to the respiratory questionnaire (71/103). Of these PBs, 15/71 (21.1%) received a diagnosis of CLD. There were no significant differences with regards to asthma, hay fever or eczema in PBs either with or without CLD. The most significant predictor for the development of asthma was smoking in the family (Odds Ratio [OR]: 11.66, 95% Confidence Interval [CI]: 2.01-67.56) with a trend toward significance for family history of asthma (OR: 3.83, 95% CI: 0.85-17.25).

CONCLUSION

The RESPOS2 has confirmed previous reports that CLD in PBs <30 weeks GA is not associated with the development of childhood asthma, hay fever or eczema. In our group of PBs, the strongest predictor of the development of asthma was smoking in the family.

Studying Associations in Health Care Research

This article discusses some of the types of relationships observed in healthcare research and depicts them in graphic form. The article begins by explaining two basic associations observed in chemistry and physics (Boyles' Law and Charles' Law), and illustrates how these associations are similar to curvilinear and linear associations, respectively, found in healthcare. Graphs of curvilinear associations include morbidity curves and survival and mortality curves. Several examples of linear relationships are given and methods of testing linear relationships with interval and ratio data are introduced (i.e., correlation and ordinary least-squares regression). In addition, 2 × 2 contingency tables for testing the association between categorical (or nominal) data are described. Finally, Sir Austin Bradford Hill's eight criteria for assessing causality from research on associations between variables are presented and explained. Three appendices provide interested readers with opportunities to practice interpreting selected curvilinear and linear relationships.

Diverging prevalences and different risk factors for childhood asthma and eczema: a cross-sectional study

OBJECTIVE

To compare the prevalences of and risk factors for asthma, wheeze, hay fever and eczema in primary schoolchildren in Aberdeen in 2014.

DESIGN

Cross-sectional survey.

SETTING

Primary schools in Aberdeen, North-East Scotland.

PARTICIPANTS

Children in Scottish school years primary 1-7 were handed a questionnaire by their class teacher to be completed by their parents and returned to the researchers by post or online.

MAIN OUTCOME MEASURES

Lifetime history of asthma, eczema and hay fever, and recent history of wheeze.

RESULTS

41 schools agreed to participate (87%). 11,249 questionnaires were distributed and 3935 returned (35%). A parent-reported lifetime history of asthma, eczema and hay fever was present in 14%, 30% and 24% of children, respectively. The odds of lifetime asthma increased with age (OR 1.1 per year, 95% CI 1.1 to 1.2), male sex (OR 1.89, 95% CI 1.4 to 2.3), parental smoking (OR 1.7, 95% CI 1.2 to 2.3) and eczema (OR 6.6, 95% CI 5.2 to 8.4). Prevalence of recent wheeze was also reported to be 14% and was positively associated with male sex, parental smoking and eczema. In contrast, parental eczema was the only identified predictor of childhood eczema risk.

CONCLUSIONS

The lifetime prevalence of asthma in primary schoolchildren was 14% in this survey, approximately half the prevalence of eczema. We report diverging prevalences in relation to previous studies in our locality, and different risk factors for asthma and eczema. These findings suggest that asthma and eczema are unlikely to have a common origin.

Helicobacter pylori update: gastric cancer, reliable therapy, and possible benefits

Helicobacter pylori infection contributes to the development of diverse gastric and extragastric diseases. The infection is necessary but not sufficient for the development of gastric adenocarcinoma. Its eradication would eliminate a major worldwide cause of cancer death, therefore there is much interest in identifying how, if, and when this can be accomplished. There are several mechanisms by which H pylori contributes to the development of gastric cancer. Gastric adenocarcinoma is one of many cancers associated with inflammation, which is induced by H pylori infection, yet the bacteria also cause genetic and epigenetic changes that lead to genetic instability in gastric epithelial cells. H pylori eradication reduces both. However, many factors must be considered in determining whether treating this bacterial infection will prevent cancer or only reduce its risk-these must be considered in designing reliable and effective eradication therapies. Furthermore, H pylori infection has been proposed to provide some benefits, such as reducing the risks of obesity or childhood asthma. When tested, these hypotheses have not been confirmed and are therefore most likely false.

Respiratory outcomes study (RESPOS) for preterm infants at primary school age

OBJECTIVE

Pulmonary function abnormalities and hospital re-admissions in survivors of neonatal lung disease remain highly prevalent. The respiratory outcomes study (RESPOS) aimed to investigate the respiratory and associated atopy outcomes in preterm infants <30 weeks gestational age (GA) and/or birth-weight (BWt) <1000 g at primary school age, and to compare these outcomes between infants with and without chronic lung disease (CLD).

METHODS

In the RESPOS 92 parents of preterm infants admitted to the Neonatal unit in Canberra Hospital between 1/1/2001 and 31/12/2003 were sent a questionnaire regarding their respiratory, atopy management and follow-up.

RESULTS

Fifty-three parents responded, including 28 preterm infants who had CLD and 25 who had no CLD. The gestational age was significantly lower in the CLD group compared to the non-CLD group [26.9 (26.3-27.5) CLD and 28.6 (28.3-29.0) non-CLD] [weeks [95% confidence interval (CI)]], as was the birth weight [973 (877.4-1068.8) CLD versus 1221 (1135.0-1307.0) non-CLD] [g (CI)]. CLD infants compared to non-CLD infants were significantly more likely to have been: given surfactant, ventilated and on oxygen at 28 days and 36 weeks. These neonates were also more likely to have: been discharged from the neonatal unit on oxygen, exhibit a history of PDA or sepsis and to have a current paediatrician. However, despite these differences, there was no significant difference in the proportion of asthma or atopic disease between the two groups.

CONCLUSIONS

The RESPOS could not demonstrate respiratory and/or atopy differences between the CLD and the non-CLD groups at primary school age.

Trends in migrant mortality rates in Australia 1981-2007: a focus on the National Health Priority Areas other than cancer

INTRODUCTION

Migrants generally have more favourable mortality outcomes than the Australian-born population. The aim of this study is to update knowledge and inform future research in this field by examining mortality from musculoskeletal conditions, asthma, cardiovascular disease, diabetes mellitus, injuries and mental conditions between 1981 and 2007 among migrants in Australia.

METHODS

Average annual sex- and age-standardised mortality rates were calculated for each migrant group, period of death registration and cause of death.

RESULTS AND CONCLUSIONS

Mortality rates decreased among most groups for asthma, cardiovascular disease and motor vehicle accidents, with rates diverging in the later time periods. The reverse was true for mental disorders, where Australian-born individuals experienced the greatest increase in mortality. Migrants generally displayed more favourable mortality outcomes than their Australian-born counterparts. Migrants from Southern Europe appeared to have the greatest advantage. However, some migrants appeared to be over-represented in the areas of diabetes, suicide and mental health.

The hygiene hypothesis in allergy and asthma: an update

PURPOSE OF REVIEW

It has been hypothesized that increased cleanliness, reduced family size, and subsequent decreased microbial exposure could explain the increases in global asthma prevalence. This review considers the recent evidence for and against the 'hygiene hypothesis'.

RECENT FINDINGS

Recent evidence does not provide unequivocal support for the hygiene hypothesis: the hygiene hypothesis specifically relates to atopic asthma, but some of the protective effects (e.g. farm exposures) appear to apply to both atopic and nonatopic asthma; asthma prevalence has begun to decline in some western countries, but there is little evidence that they have become less clean; Latin American countries with high infection rates have high asthma prevalence and the hygiene hypothesis relates to early-life exposures, but exposures throughout life may be important.

SUMMARY

There is a considerable body of evidence which warrants scepticism about the hygiene hypothesis. However, these anomalies contradict the 'narrow' version of it in which microbial pressure early in life protects against atopic asthma by suppressing T-helper 2 immune responses. It is possible that a more general version of the hygiene hypothesis is still valid, but the aetiologic mechanisms involved are currently unclear.

The pathophysiology of the hygiene hypothesis

There has been a considerable increase in the diagnosis of allergic diseases over the last decades. Prevalence of allergies in high-income countries and urban areas appears higher than in rural environments. While environmental factors like pollution or nutrition can be important, it is more likely that in the end they have a small association with allergies. Childhood infections and exposure to certain microbial antigens on the other hand seem to present a strong negative correlation with allergies, and therefore the increase of the allergic burden in the Western world has been frequently related to a decline of childhood infections giving birth to the "Hygiene Hypothesis". We address the issue with emphasis on the associated pathophysiology tightrope walking between the skepticism of the critics, which cast doubt on it, and the pilgrims' belief of having discovered allergy's Holy Grail.

Obesity and asthma at school entry: co-morbidities and temporal trends

AIM

A decline in asthma prevalence from 2000 to 2005 was reported previously. The objective is to examine the temporal trends for the prevalence of obesity and other childhood disorders and consider the extent to which associations between asthma and other co-morbidities can be accounted for by body mass index.

METHODS

Serial cross-sectional surveys of primary school entrants (n = 18,999) in the Australian Capital Territory between 2001 and 2005 were used. Asthma, recent respiratory symptoms and diabetes data were extracted from parental reports. Anthropometric measurements were obtained from health assessments by school nurses. Child obesity was defined using the age and sex-specific Cole criteria. Time trends for the prevalence of obesity and other disorders, and the association between 'current asthma' and co-morbidities were analysed using multiple logistic regression and other analyses.

RESULTS

Obesity prevalence was 5.24% in 2001 decreasing to 3.60% in 2005 (test of linear trend P = 0.02). Overweight (adjusted odds ratio (AOR) 1.30 (95% confidence interval (CI) 1.16, 1.46), P < 0.001) and obese (AOR 1.36 (95% CI 1.13, 1.62), P = 0.001) children were more likely to report 'asthma ever'. Children with diabetes (AOR 9.35 (95% CI 3.11, 28.12, P < 0.001)) and attention deficit (AOR 3.39 (95% CI 2.04, 5.64), P < 0.001) were more likely to report 'current asthma'.

CONCLUSIONS

The pattern of association with co-morbidities was different for asthma and obesity. The temporal decline/plateau effect in 'current asthma' could not be explained by concurrent body mass index changes. The decline in obesity was largely driven by the 2005 findings. Longer term trends need to be evaluated further.

Investigating international time trends in the incidence and prevalence of atopic eczema 1990-2010: a systematic review of epidemiological studies

The prevalence of atopic eczema has been found to have increased greatly in some parts of the world. Building on a systematic review of global disease trends in asthma, our objective was to study trends in incidence and prevalence of atopic eczema. Disease trends are important for health service planning and for generating hypotheses regarding the aetiology of chronic disorders. We conducted a systematic search for high quality reports of cohort, repeated cross-sectional and routine healthcare database-based studies in seven electronic databases. Studies were required to report on at least two measures of the incidence and/or prevalence of atopic eczema between 1990 and 2010 and needed to use comparable methods at all assessment points. We retrieved 2,464 citations, from which we included 69 reports. Assessing global trends was complicated by the use of a range of outcome measures across studies and possible changes in diagnostic criteria over time. Notwithstanding these difficulties, there was evidence suggesting that the prevalence of atopic eczema was increasing in Africa, eastern Asia, western Europe and parts of northern Europe (i.e. the UK). No clear trends were identified in other regions. There was inadequate study coverage worldwide, particularly for repeated measures of atopic eczema incidence. Further epidemiological work is needed to investigate trends in what is now one of the most common long-term disorders globally. A range of relevant measures of incidence and prevalence, careful use of definitions and description of diagnostic criteria, improved study design, more comprehensive reporting and appropriate interpretation of these data are all essential to ensure that this important field of epidemiological enquiry progresses in a scientifically robust manner.

Disparities in access to care among asthmatic children in relation to race and socioeconomic status

Asthma is one of the leading chronic illnesses among children in the United States. International epidemiological studies have also shown asthma prevalence is an increasing problem. The objective of this study was to examine the correlates of access to care among asthmatic children age 0-17 in the United States. This is a retrospective study and secondary data analysis of the 2000 National Health Interview Survey. Parametric testing using univariate, bivariate, and multivariate analyses were performed to examine health care utilization among children with asthma in the United States. It was found that Black children were highly associated with not visiting a general doctor in the past 12 months (OR 0.47; 95% CI 0.30, 0.75). Uninsured asthmatic children were associated with the risk of not seeing a general doctor in the past 12 months (OR 0.40; 95% CI 0.23, 0.69). Our study findings indicate disparities among Black children with asthma and their ability to access appropriate health care services. Additional studies are required to identify factors that contribute to the temporal trends in asthma and country of origin.

The health status of migrants in Australia: a review

This review summarizes the findings of studies conducted in Australia between 1980 and 2008 that focused on the health status of migrants in one or more of Australia's National Health Priority Areas (NHPAs), identifies gaps in knowledge, and suggests further research directions. Systematic literature searches were performed on CINAHL, MediText, PsycINFO, and MEDLINE. It was found that the majority of migrants enjoy better health than the Australian-born population in the conditions that are part of the NHPAs, with the exception of diabetes. Mediterranean migrants have particularly favorable health outcomes. The migrant health advantage appears to deteriorate with increasing duration of residence. Many of the analyzed studies were conducted more than 10 years ago or had a narrow focus. Little is known about the health status of migrants with respect to a number of NHPAs, including musculoskeletal conditions and asthma.The health status of recently arrived migrant groups from the Middle East and Africa has not been explored in detail.

Trends in the epidemiology of asthma in England: a national study of 333,294 patients

BACKGROUND

Observations in the UK at the end of the last century found increasing trends of asthma prevalence over time. However, it has been reported that the number of new cases of asthma presenting to general practice has declined, especially among younger children. Aim To study national trends in the epidemiology of asthma.

METHODS

A cross-sectional observation analysis was performed using the QRESEARCH database, which is one of the world's largest national aggregated health databases containing records from 422 English practices yielding 30 million patient-years of observation. Data was extracted on 333,294 individuals with a recorded diagnosis of asthma and calculated annual age-sex standardized incidence, lifetime period prevalence and asthma-related prescribing rates for each year from 2001-2005.

RESULTS

The incidence rate of asthma decreased in all patients (2001: 6.9 (95% confidence intervals [CI] 6.8-7.0); 2005: 5.2 (95% CI 5.1-5.3) per 1000 patient-years, p<0.001), but most particularly in children under 5 years of age (-38.4%) where a decrease in the lifetime prevalence of asthma (-34.3%) was also found. However, the lifetime prevalence rate of asthma for adults increased (15-44 years: 23.3%; 45-64 years: 27.7%; >65 years: 21.5%) with an estimated 5,658,900 (95% CI 5,639,700-5,678,200) or approximately one person in nine having being diagnosed with asthma in England. The number of asthma-related prescriptions also increased over the study period (17.1%), such that in 2005 an estimated 32,577,300 (95%CI 32,531,600-32,623,000) prescriptions were issued.

CONCLUSIONS

This large national study reveals that the rate of new diagnoses of asthma appears to have passed its peak; however, the number of adults with a lifetime asthma diagnosis continues to rise. Whether these trends are genuine or are a result of the introduction of incentives and guidelines to improve identification and recording of asthma or changing diagnostic trends is a question with important public health implications and one, therefore, that warrants detailed further enquiry.

Is the prevalence of asthma declining? Systematic review of epidemiological studies

Asthma prevalence has increased very considerably in recent decades such that it is now one of the commonest chronic disorders in the world. Recent evidence from epidemiological studies, however, suggests that the prevalence of asthma may now be declining in many parts of the world, which, if true is important for health service planning and also because this offers the possibility of generating and testing new aetiological hypotheses. Our objective was to determine whether the prevalence of asthma is declining worldwide. We undertook a systematic search of EMBASE, Medline, Web of Science and Google Scholar, for high quality reports of cohort studies, repeat cross-sectional studies and analyses of routine healthcare datasets to examine international trends in asthma prevalence in children and adults for the period 1990-2008. There were 48 full reports of studies that satisfied our inclusion criteria. The large volume of data identified clearly indicate that there are, at present, no overall signs of a declining trend in asthma prevalence; on the contrary, asthma prevalence is in many parts of the world still increasing. The reductions in emergency healthcare utilization being reported in some economically developed countries most probably reflect improvements in quality of care. There remain major gaps in the literature on asthma trends in relation to Africa and parts of Asia. There is no overall global downward trend in the prevalence of asthma. Healthcare planners will for the foreseeable future, therefore, need to continue with high levels of anticipated expenditure in relation to provision of asthma care.

Does eczema lead to asthma?

The nature of the relationship between eczema, asthma, and allergic rhinitis has been controversial. It has been commonly held that these disorders, while sharing genetic and environmental risk factors, are unrelated disorders that may develop sequentially along an atopic pathway. Conversely, the link between eczema and these later-onset respiratory disorders may be causal. This review examines the relationship between eczema, asthma, and allergic rhinitis in the context of the atopic march, the skin barrier, and recent developments in eczema genetics; and we propose that the relationship is causal. We describe a plausible biological pathway with eczema as the first step in a progressive atopic march that over time leads to asthma and/or allergic rhinitis. Such a pathway has implications for our understanding of these disorders and steps that might be made to prevent the development of asthma in particular. We propose that intervention studies in eczema should be conducted to confirm or refute this causal relationship. Such studies may materially improve the quality of life of eczema patients and will have important public health benefits if the interventions lead to a reduction in the burden of asthma.

Innate immunity and asthma

Asthma remains a major health problem worldwide that has increased in developed countries. Much of the focus in asthma research in the past has been on adaptive, antigen-dependent immune responses. Recent work suggests that the innate, non-antigen-dependent immune system plays a critical role in asthma pathogenesis. Here we will highlight innate receptors and cells in the context of allergic responses. Reviewing animal models and human studies, we focus on interactions of innate and adaptive immunity.