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Aim To measure the long-term improvement in the documented provision of an asthma action plan (AAP) to children with asthma and wheeze discharged from the Emergency Department following the introduction of the electronic AAP (eAAP) and to determine the need for an electronic pre-school wheeze action plan in our population. Methods A retrospective case note review, from July 2014 to June 2015, of all patients over 12 months old discharged from the Emergency Department or Emergency Medical Unit, with a discharge diagnosis of either asthma or wheeze. The primary outcome was the documentation of an AAP, either recorded electronically as an eAAP or a report of an AAP as part of the patient medical record. Results Two thousand three hundred and forty-two patients were included in the study, 926 with asthma and 1416 with wheeze. The median age was 3.3 years (interquartile range (IQR) 3.5, range 1–15.9 years). The median age of the children with asthma was 5.3 years (IQR 4.6) and of the children with wheeze was 2.5 years (IQR 2.0).Overall, 1683 (71.9%) children had a documented AAP, with a significant difference between those with a discharge diagnosis of asthma (85.9%) compared with wheeze (62.9%), P

Purpose Improved mammographic sensitivity is associated with reduced mammographic density. This study aims to: provide a preliminary report on mammographic density among women in Riyadh; identify risk factors associated with mammographic density; and consider the potential implications for screening practices. Methods Based on a cross-sectional design, we examined a total of 792 women using an area-based mammographic density method (LIBRA). Spearman's correlation, Mann-Whitney U, Kruskal–Wallis and binary logistic regression were used for analyses. Results The study population had a mean age of 49.6 years and a high proportion of participants were overweight or obese (90%). A large number of women had low mammographic density, with a mean dense breast area of 19.1 cm2 and percent density of 10.3 cm2. Slightly more than half of the variations in the dense breast area and percent density models were explained by BMI. In the adjusted analyses, BMI, menopausal status, age at menarche and number of children remained statistically significant predictors. Conclusion Given the high proportion of women with low mammographic density, our findings suggest that women living in Riyadh may not require additional imaging strategies beyond mammography to detect breast cancers. The high proportion of obese women reported here and across Saudi Arabia suggests that mammographic density is less likely to have an adverse impact on mammographic sensitivity. Thus and to improve clinical outcomes among Saudi women, annual mammography and commencing screening at a younger age are suggested. Additional studies are required to shed further light on our findings.

Malnutrition and elevated inflammatory markers have a negative impact on clinical outcomes in cancer patients. Few studies have investigated the associations between inflammatory makers, nutritional status and survival. This study investigates the association between nutritional status, inflammatory markers and overall survival (OS) in patients with advanced cancer. This prospective cohort study recruited 114 adult patients from January 2007 to January 2010. It included patients diagnosed with advanced cancer, good Eastern Cooperative Oncology Group (ECOG) performance status 0–2, a prognosis of more than 3 months and had not received chemotherapy for advanced cancer prior to enrolment. Baseline data were collected prior to commencement of chemotherapy. Patients were followed up from the date of baseline nutritional assessment until the date of death or the date that data were last updated, whichever came first. Malnourished cancer patients had statistically significant higher concentrations of serum C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR) or modified Glasgow Prognostic Score (mGPS) prior to starting chemotherapy. In univariate analyses to predict survival, mGPS 1 or 2 had a hazard ratio (HR) of 1.81 (95 % confidence interval (CI) 1.13–2.89) and NLR ≥ 5 had a HR of 1.13 (95 % CI 1.08–4.60) and malnutrition (HR of 1.66 for Patient-Generated Subjective Global Assessment (PG-SGA) B (95 % CI 1.02–2.71), and HR for severely malnourished patients (PG-SGA C) was 2.73 (95 % CI 1.50–4.96). Inflammatory markers were statistically associated with malnutrition. Malnutrition and mGPS were significant independent predictors of overall survival in patients with advanced cancer.

Purpose Rates of women with breast cancer have increased rapidly in recent years in Vietnam, with over 10,000 new patients contracting the disease every year. This study was conducted to identify demographic, reproductive and lifestyle risk factors for breast cancer in Vietnam. Materials and methods Breast density, demographic, reproductive and lifestyle data of 269 women with breast cancer and 519 age-matched controls were collected in the two largest oncology hospitals in Vietnam (one in the north and one in the south). Baseline differences between cases and controls in all women, premenopausal and postmenopausal women were assessed using chi-squared tests and independent t tests. Conditional logistic regression was used to derive odds ratios (OR) for factors that had statistically significant associations with breast cancer. Results Vietnamese women with breast cancer were significantly more likely to have a breast density > 75% (OR, 1.7), be younger than 14 years at first menstrual period (OR, 2.2), be postmenopausal (OR, 2.0), have less than three pregnancies (OR, 2.1), and have less than two babies (OR, 1.7). High breast density (OR, 1.6), early age at first menstrual period (OR, 2.6), low number of pregnancies (OR, 2.3), hormone use (OR, 1.8), and no physical activities (OR, 2.2) were significantly associated with breast cancer among premenopausal women, while breast density (OR, 2.0), age at first menstrual period (OR, 1.8), number of pregnancies (OR, 2.3), and number of live births (OR, 2.4) were the risk factors for postmenopausal women. Conclusion Breast density, age at first menarche, menopause status, number of pregnancies, number of babies born, hormone use and physical activities were significantly associated with breast cancer in Vietnamese women.

Aim: To describe the use of diagnostic labels by clinicians for children with autism spectrum disorders (ASD) and calculate the label-specific and overall agreement between diagnostic labels and Diagnostic and Statistical Manual of Mental Disorders – Fourth Edition (DSM-IV) diagnoses provided by the same clinician. Methods: State-wide active surveillance was used to ascertain children newly recognised with one or more DSM-IV criteria for autistic disorder aged 0–15 years (incident cases) in New South Wales (NSW) between July 1999 and December 2000. Clinicians were asked to supply a diagnostic label and then complete DSM-IV criteria for each child reported. Results: Questionnaires with diagnostic label and DSM-IV criteria were returned for 348 children. The agreement between labels used and diagnosis based on DSM-IV classification system was the highest for autism (97%) and lower for labels of Asperger disorder, pervasive developmental disorder – not otherwise specified or atypical autism (27%). Kappa overall agreement was 0.31. Level of agreement between label and DSM-IV diagnosis was similar for questionnaires completed by multidisciplinary teams, psychiatrists, paediatricians and psychologists working as part of a team. Conclusion: A lack of agreement between the diagnostic labelling used by clinicians and diagnosis based on DSM-IV criteria indicates a lack of consistency in diagnostic communication that is necessary to provide best clinical care, appropriate services and relevant information to parents and carers.

Background This study was commenced in 1999 with the aim of examining risk factors for autism using established population-based data for comparison. Methods Cases were ascertained using active surveillance and compared with birth data. Results Four risk factors were found to be significantly associated with autism using binary logistic regression analysis; being male [adjusted odds ratio (OR) 4.7, 95% confidence interval (CI) 3.2–7.0], being born prematurely (adjusted OR 2.2, 95% CI 1.5–3.5), having maternal age ≥35 years (adjusted OR 1.7, 95% CI 1.2–2.4) and having a mother born outside Australia (adjusted OR 1.4, 95% CI 1.0–1.9). For analysis completed for pregnancies, rather than live births, multiple birth was also a significant risk factor for one or more children of the pregnancy to be affected by autism (adjusted OR 2.5, 95% CI 1.1–5.5). There was a statistically significant trend towards increasing risk with increasing risk factor ‘dose’ for gestational age (P = 0.019), multiple birth (P = 0.016) and maternal age (P

ObjectiveThis study evaluates the contribution of energy-dense, nutrient-poor ‘extra’ foods to the diets of 16–24-month-old children from western Sydney, Australia.DesignAn analysis of cross-sectional data collected on participants in the Childhood Asthma Prevention Study (CAPS), a randomised trial investigating the primary prevention of asthma from birth to 5 years. We collected 3-day weighed food records, calculated nutrient intakes, classified recorded foods into major food groups, and further classified foods as either ‘core’ or ‘extras’ according to theAustralian Guide to Healthy Eating.SettingPregnant women, whose unborn child was at risk of developing asthma because of a family history, were recruited from all six hospitals in western Sydney, Australia. Data for this study were collected in clinic visits and at participants’ homes at the 18-month assessment.ParticipantsFour hundred and twenty-nine children participating in the CAPS study; 80% of the total cohort.ResultsThe mean consumption of ‘extra’ foods was ∼150 g day− 1and contributed 25–30% of the total energy, fat, carbohydrate and sodium to the diets of the study children. ‘Extra’ foods also contributed around 20% of fibre, 10% of protein and zinc, and about 5% of calcium. Children in the highest quintile of ‘extra’ foods intake had a slightly higher but not significantly different intake of energy from those in the lowest quintile. However, significant differences were evident for the percentage of energy provided by carbohydrate and sugars (higher) and protein and saturated fat (lower). The intake of most micronutrients was also significantly lower among children in the highest quintile of consumption. The intake of ‘extra’ foods was inversely associated with the intake of core foods.ConclusionsThe high percentage of energy contributed by ‘extra’ foods and their negative association with nutrient density emphasise the need for dietary guidance for parents of children aged 1–2 years. These preliminary data on commonly consumed ‘extra’ foods and portion sizes may inform age-specific dietary assessment methods.

Early life exposures may be important in the development of asthma and allergic disease.To test house dust mite (HDM) avoidance and dietary fatty acid modification, implemented throughout the first 5 years of life, as interventions to prevent asthma and allergic disease.We recruited newborns with a family history of asthma antenatally and randomized them, separately, to HDM avoidance or control and to dietary modification or control. At age 5 years, they were assessed for asthma and eczema and had skin prick tests for atopy.Of 616 children randomized, 516 (84%) were evaluated at age 5 years. The HDM avoidance intervention resulted in a 61% reduction in HDM allergen concentrations (microg/g dust) in the child's bed but no difference in the prevalence of asthma, wheeze, or atopy (P.1). The prevalence of eczema was higher in the active HDM avoidance group (26% vs 19%; P = .06). The ratio of omega-6 to omega-3 fatty acids in plasma was lower in the active diet group (5.8 vs 7.4; P.0001). However, the prevalence of asthma, wheezing, eczema, or atopy did not differ between the diet groups (P.1).Further research is required to establish whether other interventions can be recommended for the prevention of asthma and allergic disease.House dust mite avoidance measures and dietary fatty acid modification, as implemented in this trial during infancy and early childhood, did not prevent the onset of asthma, eczema, or atopy in high-risk children.

Objective Proteins are the major effectors of biological structure and function. Oxidation-induced changes to protein structure can critically impair protein function, with important pathologic consequences. This study was undertaken to examine whether oxidation-induced changes to protein structure occur during pediatric cardiopulmonary bypass and to examine the association with postoperative outcome. Methods Elevation of the 3,4-dihydroxyphenylalanine content of a protein relative to its native tyrosine content indicates structural damage due to oxidation. Protein 3,4-dihydroxyphenylalanine/native tyrosine ratios were measured before surgery and up to 6 hours after institution of cardiopulmonary bypass in 24 children undergoing repair of congenital heart disease, who were prospectively selected to form a cyanotic and comparable acyanotic control group. Results were correlated with perioperative variables and postoperative outcomes. Results Elevation of protein 3,4-dihydroxyphenylalanine/tyrosine ratios above baseline (0.48 mmol/mol [SD, 0.11 mmol/mol] vs 0.36 mmol/mol [SD, 0.13 mmol/mol]; P = .001) occurred within 30 minutes of initiating cardiopulmonary bypass in cyanotic but not in acyanotic children and correlated inversely with preoperative arterial oxygen saturation ( R = −0.52; P = .03). Protein 3,4-dihydroxyphenylalanine/tyrosine ratios were also increased above baseline at 120 minutes (0.44 mmol/mol [SD, 0.12 mmol/mol]; P = .007) and 180 minutes (0.40 mmol/mol [SD, 0.14 mmol/mol]; P = .01) after the institution of cardiopulmonary bypass in children who underwent prolonged procedures. Elevation of 3,4-dihydroxyphenylalanine/tyrosine during prolonged procedures was associated with postoperative arrhythmias and the need for increased inotropic support ( P = .001). Conclusions Oxidative injury to proteins occurs during pediatric cardiopulmonary bypass. Cyanotic children are most at risk, particularly those undergoing prolonged procedures, in whom elevation of the protein 3,4-dihydroxyphenylalanine/tyrosine ratio is associated with increased postoperative morbidity.

Recently there has been controversy about how many children are affected by autism and whether the incidence of autism is increasing. This paper updates existing reviews and explores the reasons for the controversy.

The objective of this study was to assess whether exposure to house dust mite allergens has an influence on respiratory symptoms and atopy at 18 months of age. A total of 616 women at risk of having a child who would develop asthma because of a family history were recruited from the antenatal clinics of six hospitals in Sydney, Australia. Families were randomized to a house dust mite avoidance group or a control group. Dust was collected from children's beds at regular intervals to measure house dust mite allergen (Der p 1) concentrations which were categorized into quintiles of exposure. At the age of 18 months, 529 children (85.9% of total sample) had an assessment of symptoms by a research nurse blinded to group status. Atopy by skin prick tests and serum IgE were also measured. Atopy to inhaled allergens (p = 0.79) or to Der p 1 was not associated with Der p 1 exposure (p = 0.87). "Doctor diagnosed asthma," "wheeze ever," and "wheeze in the absence of a cold" did not decrease with quintile of exposure...

Background Two factors thought to influence the risk of asthma are the promoting effect of sensitization to house dust mites and the preventive effect of increased omega-3 fatty acids. Although house dust mite allergen avoidance has been used as a preventive strategy in several trials, the effect of omega-3 fatty acid supplementation in the primary prevention of asthma and allergic disease is not known. Objective To measure the effects of dietary supplementation with omega-3 fatty acids and house dust mite allergen avoidance in children with a family history of asthma. Methods A total of 616 children at high risk of asthma were enrolled antenatally in a randomized controlled trial, and 526 children remained in the trial at age 3 years. The outcomes were symptoms of allergic disease and allergen sensitization. Results There was a significant 10.0% (95% CI, 3.7-16.4) reduction in the prevalence of cough in atopic children in the active diet group ( P =.003; number needed to treat, 10) but a negligible 1.1% (95% CI, −7.1 to 9.5) reduction cough among nonatopic children. There was a 7.2% (95% CI, 10.11-14.3) reduction in sensitization to house dust mite in the active allergen avoidance group ( P =.05; number needed to treat, 14). No significant differences in wheeze were found with either intervention. Conclusion These results suggest that our interventions, designed to be used in simple public health campaigns, may have a role in preventing the development of allergic sensitization and airways disease in early childhood. This offers the prospect of reducing allergic disease in later life.

Asthma is a leading cause of morbidity for children and is a major public health problem in Australia. Ecological and temporal data suggest that dietary factors may have a role in recent increases in the prevalence of asthma.The aim of conducting this study was to investigate whether childhood asthma was associated with the ratio of omega 6 (n-6) to omega 3 (n-3) fatty acids in the diet (n-6:n-3).The Western Australian Pregnancy Cohort Study is a prospective birth cohort of 2602 children. Using a nested case-control cross-sectional study design within this cohort, a group of children were identified as cases with current asthma at 6 or at 8 years of age or as controls with no asthma at 6 or at 8 years. Dietary details including n-6 and n-3 fatty acid intake data were collected by parent response to a questionnaire when the children were 8 years old. Logistical regression was used to compare quartiles of n-6:n-3 intake in cases and controls. Adjustment was made for covariates: gender, gestational age, breastfeeding, older siblings, maternal smoking during pregnancy, maternal age, maternal asthma, child's current age in months, body mass index, total energy intake, and antioxidant intake (vitamins A, C, E, and zinc).A response rate of 83% was achieved by providing complete data from 335 children [49% cases with current asthma (n = 166), 51% controls (n = 169)]. Following adjustment for covariates the association between the ratio of n-6:n-3 fatty acids and risk for current asthma was statistically significant (p = 0.022).We found evidence for a modulatory effect of the dietary n-6:n-3 fatty acid ratio on the presence of asthma in children. Our results provide evidence that promotion of a diet with increased n-3 fatty acids and reduced n-6 fatty acids to protect children against symptoms of asthma is warranted.

Introduction The association between snoring, nocturnal cough, and allergic symptoms in young children is not known. Objective To measure the prevalence of habitual snoring and its association with nocturnal cough, asthma, and hay fever in preschool children. Setting A cross-sectional study. Subjects Preschool children aged 2 to 5 years. Method The data were collected in a cross-sectional study. A total of 974 children were randomly selected from two areas of Lismore and Wagga Wagga in New South Wales, Australia. Results The prevalence of snoring was 10.5%, with no gender difference (p = 0.99) or trend association with age (p = 0.58). The association between snoring and nocturnal cough was highly significant (odds ratio [OR], 3.68; 95% confidence interval [CI], 2.41 to 5.63; p=0.001). This association was significant in both the nonasthmatic and asthmatic groups when examined separately. Snoring was also significantly associated with asthma (OR, 2.03; 95% CI, 1.34 to 3.10; p=0.001). In subjects without hay fever, the association between snoring and asthma was also highly significant (41.2% vs 24.8%; OR, 2.12; 95% CI, 1.34 to 3.37; p=0.001). Conclusion The prevalence of snoring in preschool children was 10.5% for both genders. Snoring was significantly associated with both nocturnal cough and asthma. Because snoring, asthma, and nocturnal cough may have a common etiology, it is possible that effective treatment of one symptom may lead to reductions in the presence or severity of the other symptoms.

Studies of maternal asthma in pregnancy have shown an increased risk of adverse neonatal and maternal outcomes such as preeclampsia, hypertension, cesarean delivery, prematurity, low birth weight, and perinatal/neonatal mortality. However, results are not consistent between studies. We studied the association between maternal asthma and various adverse neonatal and maternal outcomes and explored whether there is any evidence that pregnancy exacerbates maternal asthma. The data were collected as part of the Childhood Asthma Prevention Study. Pregnant women with asthma or women whose partners or other children had current symptoms of asthma were recruited at six Sydney hospitals. All women recruited were post 36 weeks gestation and were living within 30 km of the study recruitment center. Information about family history of asthma was collected using a questionnaire at 36 weeks gestation and subsequent information about antenatal and perinatal events was obtained from hospital records. Data from 611 pregnant women were available for analysis, 340 of whom had asthma. Hypertension was significantly more common in asthmatics than in nonasthmatics [OR = 2.16 (1.02-4.6), p < 0.043]. The prevalence of gestational diabetes, labor complications, delivery complications, and adverse neonatal outcomes did not differ significantly between the groups. We also found that the course of maternal asthma usually remains unchanged during pregnancy, but that more severe asthma is likely to get worse. We have confirmed previous observations that women with asthma are at increased risk of hypertension in pregnancy, which is consistent with studies that show that pregnant asthmatic women have a slightly increased risk of preeclampsia. However, we did not find evidence of an increased risk of adverse perinatal outcomes.

Background: Observational studies have linked house dust mite (HDM) exposure and dietary fatty acid intake with asthma in childhood. However, definitive evidence of their role in the etiology of asthma requires a randomized controlled trial. Objective: We hypothesized that the incidence of asthma and allergy in high-risk children would be reduced by avoidance of HDM allergens, supplementation with omega-3 fatty acids, or the combination of these strategies. We present the results of an interim analysis reporting outcomes assessed at 18 months. Methods: A total of 616 pregnant women were randomized to an HDM avoidance intervention, comprising the use of impermeable mattress covers and an acaricide or control and the use of an oil supplement, margarines, and cooking oils containing high levels of omega-3 fatty acids or control. Atopic status was measured by skin prick testing. Symptoms, diagnoses, and medication histories were elicited by means of parental interviews. Results: The diet intervention resulted in a 9.8% absolute reduction (95% CI, 1.5-18.1; P = .02) in the prevalence of any wheeze and a 7.8% absolute reduction (95% CI, 0.5-15.1, P = .04) in prevalence of wheeze of >1 week, but it had no effect on serum IgE, atopy, or doctors' diagnosis of asthma. The HDM avoidance intervention did not affect these outcomes but was associated with a lower use of oral steroids. Conclusion: Increasing dietary omega-3 fatty acids might have a beneficial effect on the prevalence of wheeze during the first 18 months of life. Follow-up to age 5 years, when the effect of the interventions on asthma risk will be assessed, is underway.

BackgroundYoung women are under-represented in cardiovascular disease research, with obesity and cardiometabolic risk factor interventions generally targeting older adults. Furthermore, appropriate study designs for young women remain uncertain. This study aimed to assess the impact of a 12 week multi-disciplinary lifestyle intervention on cardiometabolic risk factors in premenopausal women with abdominal obesity.MethodsWomen aged 18-30 y with abdominal obesity [waist circumference (WC) ≥ 80 cm] were randomised to a 12 week lifestyle intervention (n = 26) of physical activity, nutrition education and cognitive behavioural therapy, or a wait-list control group (n = 17). Both groups completed anthropometric, biochemical, nutrition and fitness testing, at pre (0 weeks) and post (12 weeks), with intervention participants completed follow-up testing at 24 weeks.ResultsResults from a linear mixed model showed no between-group differences, other than increased physical activity in the intervention group, at post. In the intervention group alone, positive within-group changes were observed in WC, waist-hip-ratio (WHR), waist-height-ratio (WHtR), resting heart rate, blood pressure, predicted VO2max, and total energy intake. Most changes were maintained at 24 weeks post-intervention. Similar within-group improvements were observed in control participants in WC, WHR, WHtR, and systolic blood pressure but no changes were detected in physical activity and nutrition.ConclusionsCardiometabolic risk factors were decreased as a result of a lifestyle intervention in young women with abdominal obesity. It is difficult to describe observations in the control group without greater understanding of the behaviour of wait-list participants.Trial registrationAustralian New Zealand Clinical Trials Registry ACTRN12612001017819.

Background: Although many children with asthma may have a remission as they grow and other children who did not have asthma may develop asthma in adult life, knowledge about the factors that influence the onset and prognosis of asthma during adolescence and young adulthood is very limited. Methods: A cohort of 8–10 year old children (n=718) living in Belmont, New South Wales, Australia were surveyed six times at 2 yearly intervals from 1982 to 1992, and then again 5 years later in 1997. From this cohort, 498 subjects had between three and seven assessments and were included in the analysis. Atopy, airway hyperresponsiveness (AHR), and wheeze in the last 12 months were measured at each survey. Late onset, remission, and persistence were defined based on characteristics at the initial survey and the changes in characteristics at the follow up surveys. Results: The proportion of subjects with late onset atopy (13.7%) and wheeze (12.4%) was greater than the proportion with remission of atopy (3.2%) and wheeze (5.6%). Having atopy at age 8–12 years (OR 2.8, 95% CI 1.5 to 5.1) and having a parental history of asthma (OR 2.0, 95% CI 1.02 to 4.13) were significant risk factors for the onset of wheeze. Having AHR at age 8–12 years was a significant risk factor for the persistence of wheeze (OR 4.3, 95% CI 1.3 to 15.0). Female sex (OR 1.9, 95% CI 1.01 to 3.60) was a significant risk factor for late onset AHR whereas male sex (OR 1.9, 95% CI 1.1 to 2.8) was a significant risk factor for late onset atopy. Conclusions: The onset of AHR is uncommon during adolescence, but the risk of acquiring atopy and recent wheeze for the first time continues during this period. Atopy, particularly present at the age of 8–10 years, predicts the subsequent onset of wheeze.

International audience; Objectives: This study aimed to (1) investigate cardiometabolic risk markers in young women (18–30 years) with overweight/obesity, and (2) establish whether the measures of waist circumference and body mass index possess similar associations of cardiometabolic risk. Design: Cross-sectional. Methods: Cardiometabolic risk factors including, anthropometric, metabolic syndrome markers, biochemical , and other health/fitness indicators were assessed in women when classified as overweight/obese by waist circumference [waist circumference 91.9 ± 10.1 cm, age 22.3 ± 3.5 years, n = 38] versus control [n = 30, waist circumference 71.4 ± 3.5 cm, age 20.1 ± 0.9 years], and when classified by body mass index [n = 35, body mass index 32.2 ± 5.2 kg m 2 , age 22.5 ± 3.6 years] versus control [body mass index 21.7 ± 1.9 kg m 2 , age 20.1 ± 0.9 years, n = 33]. Results: Compared with controls, women with overweight/obesity (classified by waist circumference or body mass index) displayed elevated body mass, systolic blood pressure and homeostasis model assessment of insulin resistance, and reduced estimated VO 2max and weekly physical activity, with no differences in self-reported energy intake. The unadjusted odds ratio of being classified with overweight/obesity and an elevated homeostasis model assessment of insulin resistance and/or less than recommended physical activity ranged between 5.1 and 10.0. Receiver operator characteristic curves indicated waist circumference , body mass index and waist-to-height ratio cutoff points of ≥84.2 cm, ≥30.6 kg m −2 and ≥0.5, respectively, for homeostasis model assessment of insulin resistance, and ≥80.6 cm, ≥25.2 kg m −2 and ≥0.46, respectively, for less than recommended physical activity. Conclusions: Waist circumference and body mass index have similar associations with cardiometabolic risk, with greater homeostasis model assessment of insulin resistance and lower physical activity, rather than differences in traditional metabolic syndrome markers, observed in young women with over-weight/obesity.

Background: House-dust-mite allergen content differs between houses and is thought to be a function of the housing characteristics and furnishing choices that affect indoor microclimate and mite proliferation. The importance of these features may differ with regional climates. Methods: Concentrations of mite allergen were analysed as a function of housing features. Information on housing features was collected by questionnaire in 50 houses in two towns in a dry inland region of Australia. Mite allergen (Der p 1) was measured by ELISA in dust samples collected on five occasions over 2 years from beds and floors. Results: Der p 1 was detected in all houses. Many housing features did not influence mite allergen concentrations. However, the presence of evaporative cooling increased mite allergen by 3.34-fold in beds (P=0.007) and 3.94-fold in floors (P=0.003). Mite allergen was threefold higher in mattresses >5 years old, and synthetic and feather duvets tended to have higher and lower levels of mite allergen, respectively. Conclusions: In houses in dry, inland regions of Australia, evaporative cooling and older mattresses are associated with higher concentrations of mite allergen. Alternative forms of air conditioning to evaporative cooling may be useful for control of mite allergen in dry regions.

The fungus Alternaria is known to be allergenic and is one of the most common fungi worldwide. We investigated the extent to which exposure to Alternaria increases the severity of asthma. We undertook a prospective cohort study in Australia of 399 school children who had positive skin tests to one or more aeroallergens. Airway responsiveness to histamine, wheeze, and bronchodilator use in 1 mo was measured five times between 1997 and 1999. Airway hyperresponsiveness was defined as PD(20)FEV(1) = 3.9 micromol histamine. Airborne concentrations of Alternaria spores were measured throughout the study, and mean daily concentrations over 1 mo ranged from 2.2 to 307.7 spores/m(3) of ambient air. Using generalized estimating equations, we found that airway responsiveness, wheeze, and bronchodilator use increased significantly in association with increased spore concentrations and that the increase in airway responsiveness was greater in children sensitized to Alternaria than in other children (p = 0.01). The odds ratio for airway hyperresponsiveness in children sensitized to Alternaria was 1.26 (95% CI, 1.14 to 1.39) after an increase in mean exposure of 100 spore/m(3)/d over 1 mo. These results suggest that Alternaria allergens contribute to severe asthma in regions where exposure to the fungus is high.

Objective: To compare the prevalence and risk factors for wheeze, asthma diagnosis and hayfever in Aboriginal and non-Aboriginal children living in rural towns in Australia. Design and setting: Cross-sectional study in two towns in rural NSW, Australia, 1997. Participants: Primary school children (aged 7-12 years) classified by their parents as being of Aboriginal (n = 158) or of non-Aboriginal (n = 1282) origin. Main outcome measures: Atopy measured by skinprick tests and respiratory symptoms measured by parent-completed questionnaire. Results: Aboriginal children were less likely to be atopic (36.2% v 45.6%; 95% Cl for the difference, -17.6 to -1.3) and to have hayfever (23.3% v 35.2%; 95% Cl for the difference, -19.1 to -4.6) than non-Aboriginal children, but were equally likely to have had wheeze (31.0% v 27.3%) and asthma (39.4% v 39.3%). Among Aboriginal children, having had bronchitis before age two was a strong risk factor for wheeze (adjusted odds ratio (aOR), 9.3; 95% Cl, 2.8-30.2) and asthma (aOR, 19.3; 95% Cl, 4.7-79.3) and having a parent with hayfever was a strong risk factor for hayfever (aOR, 17.9; 95% Cl, 3.5-90.8), but these risk factors were weaker among non-Aboriginal children. Conclusions: Asthma and wheeze are equally prevalent in Aboriginal and non-Aboriginal children living in the same towns, but appear to have a different aetiology.

The Childhood Asthma Prevention Study is a randomized controlled trial to measure whether the incidence of atopy and asthma can be reduced by house dust mite allergen reduction, a diet supplemented with omega-3 fatty acids, or a combination of both interventions. Six hundred and sixteen pregnant women whose unborn children were at high risk of developing asthma because of a family history were randomized prenatally. Study groups are as follows: Group A (placebo diet intervention, no house dust mite reduction), Group B (placebo diet intervention, active house dust mite reduction), Group C (active diet intervention, no house dust mite reduction), and Group D (active diet intervention, active house dust mite reduction). The house dust mite reduction intervention comprises use of physical and chemical methods to reduce allergen contact. The dietary intervention comprises use of a daily oil supplement from 6 months or at onset of bottle-feeding, and use of margarine and cooking oils based on sunflower or canola oils to increase omega-3 dietary intake. Data is collected quarterly until the infant is 1 year old and then half yearly until age 5 years. Questionnaires are used to collect respiratory illness history and information about diet and home environment. Dust is collected from the child's bed and bedroom and playroom floors. Blinded assessments are conducted at 18 months, 3 years, and 5 years. Skin prick tests to common allergens, blood tests, and detailed illness, medication use, and vaccination histories are collected. Primary outcomes will be the development of allergic sensitization and the presence and severity of asthma. This study is designed to measure the effectiveness of allergen reduction and dietary supplementation, both separately and in combination, for the primary prevention of atopy and asthma. The results of this study may have important implications for public health policies to reduce the incidence of childhood asthma. Control Clin Trials 2001;22:333-354

Background Farmers' children in northern Europe have a lower prevalence of atopy, hay fever and asthma than other children. Farms in Australia differ in scale and operation from those in Europe and the prevalence of allergic diseases in children is higher. Objective To investigate whether having lived on a farm as a child in Australia is associated with a lower risk of allergic diseases. Methods Cross-sectional study of children (n = 1500) aged 7-12 years from two rural towns: Wagga Wagga in a mixed farming region, and Moree in a crop farming region. Parents answered a questionnaire and children had a skin prick test for atopy. Results Twenty percent of children had lived on a farm for at least 1 year. The effect of having lived on a farm differed between the towns (P Conclusion Having lived on a farm in Australia can confer protection against atopy in children. Further studies are needed to identify possible protective mechanisms associated with farm animals or to establish whether the protective effect is explained by other related exposures.

BACKGROUND—A study was undertaken to assess whether the recent increases in prevalence of both asthma and obesity are linked and to determine if obesity is a risk factor for diagnosed asthma, symptoms, use of asthma medication, or airway hyperresponsiveness. METHODS—Data from 1971 white adults aged 17-73 years from three large epidemiological studies performed in NSW were pooled. Doctor diagnosis of asthma ever, history of wheeze, and medication use in the previous 12 months were obtained by questionnaire. Body mass index (BMI) in kg/m2 was used as a measure of obesity. Airway hyperresponsiveness (AHR) was defined as dose of

To evaluate the association between growth in height and growth in lung function, and to identify the potential temporal relationships between airway hyperresponsiveness (AHR), respiratory symptoms, and lung function growth during adolescence and young adulthood, we analyzed data collected from the Belmont cohort. Among the 718 schoolchildren initially studied at 1982 (aged 8-10 yr), 557 were studied between two times and six times at 2-yr intervals until 1992. Baseline lung function, AHR by histamine inhalation test, and recent wheeze by questionnaires, were measured at each visit. We found that between 17 and 19 yr of age, when growth in height had stopped, growth in FEV(1) was approximately 200 ml/yr in boys and 100 ml/yr in girls. Peak growth velocity of height occurred at age 13 both in boys and in girls, whereas peak growth velocity of FEV(1) occurred at the same age only in girls and 1 yr later in boys. Having AHR and recent wheeze at the previous study time were both associated with lower subsequent growth in FEV(1), but not with subsequent growth in FVC. We conclude that lung function continues to grow after the cessation of height growth and that growth in FEV(1) is reduced in subjects with AHR and/or recent wheeze.

Background The patterns of inheritance of asthma have largely been explored using data of symptom history collected by questionnaires which are subject to bias and which may therefore distort the measured relationship. Objective The purpose of this study was to examine family patterns of allergic disease using objective measurements of atopy and of airway hyperresponsiveness (AHR). Methods A large random sample of children aged 8–11 years was studied and 3 months later, their parents were also invited for study. Of the sample of 1655 children, both parents of 661 children were studied. In all subjects, respiratory illness history was measured by questionnaire, atopy by skin tests and AHR by responsiveness to histamine. Results The odds ratio for a child to have AHR if either parent had the same condition was approximately 2.0, which was the same as the odds ratio for wheeze or diagnosed asthma in the presence of the same condition in either parent. The odds ratio for atopy was smaller (approximately 1.4, NS) but the risk of a nonatopic child having AHR if the parent had AHR was 3.0 (P = 0.01). The correlation between weal size in the child and parent was poor and the severity of AHR in the child was only modestly correlated with the severity of AHR in the parent (R = 0.51, P = 0.04). Conclusion The use of objective measurements did not strengthen the association between atopic or asthmatic conditions in the parent and child, but did suggest that atopy and AHR are inherited independently.

Early attendance at daycare has been shown to protect against atopy, as defined by a positive skin prick test. One proposed hypothesis for this association is that early exposure to other children protects against atopy by facilitating the spread of infections among children. An alternative hypothesis is that children attending daycare centers have less atopy due to lower levels of exposure to indoor allergens. Our aim was to determine whether attendance at daycare before age 2 years protects against atopy in Australian preschool age children and to test the two alternative hypotheses, as well as a number of potential confounding factors. We conducted a cross-sectional study of children aged 3–5 years living in one humid coastal city (Lismore, n = 286) and one dry, inland city (Wagga Wagga, n = 364) in New South Wales, Australia, in 1995. Atopy was assessed by skin prick tests to six common allergens. Daycare attendance and other possible risk factors for atopy were measured by a parent-completed questionnaire. Children who attended daycare before age 2 years had a reduced risk of atopy at 3–5 years. The greatest effect was seen in children who attended a daycare center (odds ratio (OR), 0.26; 95% CI, 0.14–0.50) rather than family daycare (OR, 0.66; 95% CI, 0.41–1.04). The results of this study do not support either of the proposed hypotheses, nor can the effect be explained by any of the other potential confounders measured. Further work is needed to determine the exposure that is responsible for the protective effect of daycare attendance on atopy. Pediatr Pulmonol. 2000; 30:377–384. © 2000 Wiley-Liss, Inc.

Background and Aims: To assess accurately the effect of parental smoking on the respiratory health of New South Wales (NSW) school children, we obtained a large data set by pooling data from seven cross-sectional studies conducted in NSW between 1991 and 1993. Methods: A random sample of 6394 children age eight to 11 years was studied. Respiratory symptoms, family history of asthma and parental smoking history were measured by questionnaire, atopy by skin prick test and airway hyper-responsiveness (AHR) by histamine inhalation test. Results: In total, 58.3% of children had at least one parent who smoked; 38.5% were exposed to maternal smoking. After adjusting for potential confounders, such as atopy, parental history of asthma and bronchitis in the first two years, children who were exposed to maternal smoking had a significantly increased risk of recent wheeze but not of AHR (odds ratios 1.33; 95% CI: 1.2-1.5 and 1.00; 95% CI: 0.9-1.2). Conclusions: The positive association with wheeze and the lack of an association with AHR suggests that exposure to parental smoking leads to wheezing, but does not increase airway responsiveness.

The aim of this study was to obtain quantitative information from published data on the association between environmental tobacco smoke (ETS) exposure and the prevalence of serious lower respiratory tract infections (LRTI) in infancy and early childhood. We identified 21 relevant publications on the relation between ETS and the prevalence of serious LRTI by reviewing reference lists in relevant reports and by conducting manual and computer searches (Medline database; Dissertation abstracts index of Xerox University Microfilms) of published reports between 1966 and 1995. Thirteen studies were included in a quantitative overview using random effects modeling to derive pooled odds ratios. Sensitivity analyses were conducted to test the decision rules used in extracting odds ratio data. The results of community and hospital studies are broadly consistent and show that the child of a parent who smokes is at approximately twice the risk of having a serious respiratory tract infection in early life that requires hospitalization. This association was pronounced in children younger than age two and diminished after the age of two. The combined odds ratio for hospitalization for lower respiratory tract infections in infancy or early childhood is 1.93 (95% CI 1.66-2.25); the combined odds ratio of prevalence of serious LRTI at age less than 2 years, between 0 and 6 years, and between 3 and 6 years were 1.71 (95% CI 1.33-2.20); 1.57 (1.28-1.91), and 1.25 (0.88-1.78), respectively. There was no evidence of heterogeneity across the studies in these combined odds ratios. We conclude that this meta-analysis provides strong evidence that exposure to ETS causes adverse respiratory health outcomes such as either a serious LRTI or hospitalization for LRTI. New public health campaigns are urgently needed to discourage smoking in the presence of young children.

Background: We urgently need to take steps towards reducing the prevalence of asthma in countries where the prevalence has become unacceptably high in recent years. Because we do not have any good information about causes of the increased prevalence, we cannot act directly to reverse the trend. Therefore we need to take an indirect approach and use known information of etiologic factors to try to reduce asthma in the next generation, while acknowledging that we may be dealing with different factors from those responsible for the increased prevalence. Any successful strategies will also help to ensure that developing countries do not attain such high rates of asthma in their children in coming years. Objective: This article summarizes the roles of the risk factors that identify "high-risk" children, that provide insights into mechanisms, or that have potential for primary prevention. The factors with the most potential for primary prevention are allergen exposure, parental smoking, breast-feeding, and dietary fatty acids. Conclusion: In other health models, information about risk factors has been used in successful public health interventions. It is disappointing that the important risk factors for asthma are well documented but that there have been few trials of primary prevention and no changes in public health policies. (J Allergy Clin Immunol 1999;103:1-10.)

The International Union Against Tuberculosis and Lung Disease questionnaire is widely used in epidemiologic studies of adult asthma. We examined whether the symptom questions could be classified into groups that represent different "syndromes," and whether some questions are better for predicting asthma than others. We analyzed questionnaire data from a population sample of 1,527 adults aged 18 to 55 years using factor analyses to classify the 17 respiratory symptom questions into four different groups that we termed asthma, cough, breathlessness, and urgent medical visit. The urgent medical visit was a subset of asthma. These four "syndromes" had good validity when measured against airway responsiveness to histamine, atopy to common allergens, lung function, smoking status, and body mass index. Questions that predicted asthma syndrome were those that asked about wheeze at rest or following exercise, asthma attack, chest tightness, and shortness of breath at rest. Questions about cough identified a different group of subjects who apparently did not have asthma. Questions of breathlessness did not aggregate with "asthma" or with "cough syndrome." The identification of particular questions that measure different respiratory conditions is important for epidemiologic studies when short questionnaires or more precise definitions are required.

In epidemiological studies, defining asthma as the presence of airway hyperresponsiveness (AHR) plus recent symptoms leaves two groups of subjects whose clinical significance is unclear: those with asymptomatic AHR, and those with symptoms only. The aim of the study was to determine whether subjects with symptoms only differ from the normal and asthmatic groups in the perception of airway obstruction. Six hundred and ninety seven adults completed a questionnaire of symptoms and underwent bronchial challenge with histamine to induce airway obstruction. Recent symptoms included wheeze and morning chest tightness in the last 12 months. AHR was defined as a provoking dose of histamine causing > or = 20% fall in forced expiratory volume in one second (PD20FEV1)

To explore the natural history of asthma and its relation to allergic responses, we examined the relation between total serum IgE in early adulthood and a history of respiratory symptoms, airway hyperresponsiveness (AHR), and atopy during childhood. We studied 180 subjects aged 18-20 years who had been studied since the age of 8-10 years. We measured wheeze in the previous year by questionnaire, AHR by histamine inhalation test, atopy by skin prick tests, and serum IgE levels by immunoassay. Subjects with AHR in early adulthood had higher IgE levels (mean 257.0 IU/ml) than subjects with past AHR (mean 93.3 IU/ml) or with lifelong normal responsiveness (mean 67.6 IU/ml) (P < 0.001). Subjects who had symptoms had higher IgE levels (mean 125.9 IU/ml) than those who were lifelong asymptomatic (mean 63.1 IU/ml) (P < 0.001). Recent wheeze, AHR, and allergic sensitization all had a positive relation to serum IgE, but IgE was not more predictive of AHR than skin prick tests. The finding that young adults who are sensitized to common allergens are highly likely to have AHR even in the absence of symptoms is further evidence of the fundamental role of IgE-mediated responses in the natural history of AHR throughout childhood and into adulthood.

If house dust mite allergen (Der p I) is an important cause of asthma, there should be a direct relationship between level of exposure to this allergen and asthma severity. To examine this, we studied six large random samples of children in different regions of New South Wales, Australia. We measured recent wheeze by questionnaire, airway hyperresponsiveness (AHR) by histamine inhalation test and sensitization to house dust mites by skin prick tests. Current asthma was defined as the presence of recent wheeze and AHR. We measured Der p I levels in the beds of approximately 80 children in each region. In regions where Der p I levels were high, more children were sensitized to house dust mites, and these children had significantly more AHR and recent wheeze. After adjusting for sensitization to other allergens, we found that the risk of house dust mite-sensitized children having current asthma doubled with every doubling of Der p I level. There was a modest correlation between AHR and Der p I exposure in individuals (r = 0.23, p0.03). These data suggest that house dust mite allergens are an important cause of childhood asthma and that reducing exposure to these allergens could have a large public health benefit in terms of asthma prevention.

Calculation of diurnal peak expiratory flow (PEF) variability using values before and after bronchodilator is no longer possible for many asthmatic patients because they now use beta-agonists "as needed" for symptoms rather than regularly. This study assesses the usefulness of a number of alternative PEF indices as markers of airway liability in subjects with stable, although not necessarily well-controlled, asthma. Forty-six adult subjects completed a questionnaire about symptoms and treatment in the previous 3 mo. Spirometric function and airway hyperresponsiveness (AHR) were assessed; AHR was expressed as dose response ratio (DRR) (maximal percent fall in FEV1 divided by final dose of histamine). Subjects recorded PEF morning and evening, before and after bronchodilator (if used) for 2 wk. Nine different PEF indices were calculated. Diurnal variability (amplitude percent maximum) without bronchodilator was significantly less than diurnal variability with bronchodilator. Normal indices of PEF lability were found in 42% of subjects with reduced maximal midexpiratory flow (MMEF). Most of the PEF indices correlated strongly with DRR, and less strongly with symptom score and airway obstruction. Minimum morning prebronchodilator PEF over a week (expressed as percent recent best or percent predicted) is recommended as the best PEF index of airway lability in patients with stable asthma because it correlates strongly with AHR, patients are more likely to comply with a once-daily reading, the calculation is simple, and regular use of a beta-agonist is not required.

We have calculated normal standards for lung function of Australian children and have estimated the effects on lung function of passive smoking, current asthma, past asthma, and a current respiratory infection. Three cross-sectional samples of children in school years 3-5 (aged 8-11 years) were studied. The 2765 children were from two rural regions of NSW and from the city of Sydney. Details of passive smoking and respiratory illness were collected by a questionnaire sent to parents. Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), peak expiratory flow rate (PEFR), and forced mid-expiratory flow rate (FEF25-75%) were used as measures of lung function. Airway responsiveness was assessed by histamine inhalation test. Data from 1278 "normal" children were used in regression analysis to calculate prediction models for lung function. Passive smoking was associated with reduced FEV1, PEFR, and FEF25-75%. Children with current asthma had reduced FEV1 and FEF25-75% and children with past asthma had reduced FEF25-75%. Children with a current respiratory infection had reduced FVC, FEV1, PEFR, and FEF25-75%. The effects of these deficits on the future lung function of these children is not known but is likely to be important.

Bronchial provocation tests with agents such as histamine and methacholine are commonly used in clinical and epidemiological studies of respiratory illness because bronchial hyperresponsivenes is a non-specific abnormality of the airways which is characteristic of asthma. However, measurements of bronchial responsiveness are log-normally distributed. As a result, special considerations need to be given to reporting within-subject changes in these measurements in longitudinal studies as, for example, in clinical trials or in any study in which a before-and-after experimental design is used. In these types of experiments, changes in bronchial responsiveness should not be simply expressed in the units of the measurement, such as dose of provoking agent, but must be expressed in units based on a logarithmic scale. The appropriate log-based units for measuring within-subject changes are doubling dose, fold difference or percent change. This paper explains the methods for calculating changes in these units in a statistically correct manner. All three units represent different ways of expressing the same change on a logarithmic scale. However, ‘doubling dose’ is only appropriate when it relates directly to the method of administering the provoking agent in doubling concentrations and ‘fold difference’ or ‘percent change’ are both appropriate for expressing any log-based changes. The methods for calculating changes in these units also apply to calculations of repeatability within test methods and to calculations of comparability and agreement between test methods. The methods are described solely for reporting changes in units of bronchial responsiveness but are applicable to other log-normally distributed measurements.

In recent years, airway responsiveness has commonly been measured in epidemiological studies using one of two methods. In one method, histamine is administered via a handheld DeVilbiss nebulizer and in the other, methacholine is administered via a dosimeter. Allergic sensitivity has commonly been measured by either the allergen droplet method or by Phazet. We wanted to assess the comparability of airway responsiveness and of allergic sensitivity measured by both methods. A total of 48 volunteers, including normal and asthmatic subjects, participated in the study. Subjects first underwent one of the two tests of airway responsiveness and allergic sensitivity, and then returned within 10 days to undergo tests using the second protocol. Commencement protocol was allocated in random order. There was good agreement between both methods for assessing airway responsiveness and for assessing allergic sensitivity. The difference for dose response ratio (DRR) between histamine and methacholine was a 1.19 (95% (CI) 0.78, 1.82) fold changes, which was not statistically significant. Agreement between allergic sensitivity methods was perfect for Alternaria tenuis, good for rye-grass (kappa = 0.71) and moderate for cat and Dermatophagoides pteronyssinus (kappa approximately 0.5). It is possible to compare data from epidemiological studies which use these methods.

The aim of the present study was to compare the severity of asthma in children and adults living in the same home environments. In winter 1991 and 1992, we studied two large random samples of children living in two different regions; and, three months later, we conducted a study of adults who lived with enrolled children. A total of 805 children and 814 adults attended in Lismore, and 850 children and 711 adults in Wagga Wagga. Questionnaires were used to measure symptom history, histamine inhalation challenge to measure airway hyperresponsiveness (AHR) and skin-prick tests to measure allergy. There was a higher prevalence of asthma in children than in adults: recent wheeze was 1.5 times higher; asthma medication use was 1.5 times higher; diagnosed asthma was 1.6 times higher; and AHR was two times higher. Current asthma (AHR and recent wheeze) was 9.5-11.3% in children and 5.4-5.6% in adults. These differences were statistically significant. In both regions, airway responsiveness was more severe in children who were sensitized to common allergens than in similarly sensitized adults. These results suggests that airways can develop protective mechanisms with age, or that recent environmental changes in factors such as allergen levels, diet or treatment practices have led to immunological changes and to increased airway responsiveness in this generation of children.

Objective : To investigate whether prevalence of asthma in children increased in 10 years. Design : Serial cross sectional studies of two populations of children by means of standard protocol. Setting : Two towns in New South Wales: Belmont (coastal and humid) and Wagga Wagga (inland and dry). Subjects : Children aged 8-10 years: 718 in Belmont and 769 in Wagga Wagga in 1982; 873 in Belmont and 795 in Wagga Wagga in 1992. Main outcome measures : History of respiratory illness recorded by parents in self administered questionnaire; airway hyperresponsiveness by histamine inhalation test; atopy by skin prick tests; counts of house dust mites in domestic dust. Results : Prevalence of wheeze in previous 12 months increased in Belmont, from 10.4% (75/718) in 1982 to 27.6% (240/873) in 1992 (P Conclusions : We suggest that exposure to higher allergen levels has increased airway abnormalities in atopic children or that mechanisms that protected airways of earlier generations of children have been altered by new environmental fators.

OBJECTIVE To describe aspects of the manifestations and management of asthma in a community setting. DESIGN Cross-sectional survey. SETTING A NSW provincial centre in October 1991. PARTICIPANTS Ninety-eight adults, identified from a population survey, with wheeze, shortness of breath, or cough, in the past year, and either airway hyperresponsiveness (AHR) or a reported doctor's diagnosis of asthma. MAIN OUTCOME MEASURES Histamine challenge test to measure AHR; asthma quality of life questionnaire (AQLQ) score (with the maximum score of 10 corresponding with lowest quality of life); need for medical attention or time off work; medical management and self-management of asthma; and the extent of beta 2-agonist use. RESULTS Of the 98 participants, 74 had had asthma diagnosed by their doctor, 34 had perennial asthma, and 30 had required medical attention or had missed work because of asthma in the preceding year. The median AQLQ score was 1.0 (interquartile range, 0.6-1.8). Inhaled steroids were used by 17 participants who accounted for 23% of those with medically diagnosed asthma, 32% of those with perennial asthma, 17% of those with moderate or severe AHR, 40% of those who had required medical attention or missed work because of asthma in the preceding year, and 31% of those with AQLQ scores in the top quartile. Only 18 participants owned a peak flow meter; seven had a written self-management plan; 18 stated they would respond to worsening asthma by starting or increasing treatment with inhaled steroids, and six would start therapy with orally administered steroids. Twelve had never used beta 2-agonists and only five had purchased more than 12 beta 2-agonist inhalers in the preceding year. CONCLUSIONS The spectrum of asthma in this community sample included many adults with mild disease and few with severe disease. Many were not managed in accordance with the recommendations of the Asthma Management Plan, but overuse of beta 2-agonists was not an important public health problem in this community.

OBJECTIVE To evaluate the effectiveness of the Practitioner Asthma Communication and Education (PACE) Australia program, an innovative communication and paediatric asthma management program for general practitioners. DESIGN Randomised controlled trial. SETTING General practices from two regions in metropolitan Sydney. PARTICIPANTS 150 GPs, who were recruited between 2006 and 2008, and 221 children with asthma in their care. INTERVENTION GPs in the intervention group participated in two 3-hour workshops, focusing on communication and education strategies to facilitate quality asthma care. MAIN OUTCOME MEASURES Patient outcomes included receipt of a written asthma action plan (WAAP), appropriate medication use, parent days away from work, and child days away from school or child care. GP outcomes included frequency of providing a WAAP and patient education, communication and teaching behaviour, and adherence to national asthma guidelines regarding medication use. RESULTS More patients of GPs in the intervention group reported receipt of a WAAP (difference, 15%; 95% CI, 2% to 28%; adjusted P=0.046). In the intervention group, children with infrequent intermittent asthma symptoms had lower use of inhaled corticosteroids (difference, 24%; 95% CI, -43% to -5%; P=0.03) and long-acting bronchodilators (difference, 19%; 95% CI, -34% to -5%; P=0.02). GPs in the intervention group were more confident when communicating with patients (difference 22%; 95% CI, 3% to 40%; P=0.03). A higher proportion of GPs in the intervention group reported providing a WAAP more than 70% of the time (difference, 23%; 95% CI, 11% to 36%; adjusted P=0.002) and prescribing spacer devices more than 90% of the time (difference, 29%; 95% CI, 16% to 42%; adjusted P=0.02). CONCLUSIONS The PACE Australia program improved GPs' asthma management practices and led to improvements in some important patient outcomes. TRIAL REGISTRATION Australian New Zealand Clinical Trials Registry ACTRN12607000067471.

Asthma is a major public health problem in developed countries, where it consumes a large and increasing share of scarce health resources. Ideally, medical management should be both optimal in terms of improving the patient's quality of life, and cost-effective for society. At present, there is very little information relating to costs and economic efficiency of current asthma management. Although the true total cost of asthma is unknown, current estimates suggest it is high. The main value of recent total cost estimates is that they identify the most expensive areas of asthma costs, and ideally, formal cost-effectiveness analyses should be concentrated on these areas. Asthma is still under- or inappropriately diagnosed, and undertreated. Several national and international consensus plans for the optimal management of asthma in children and adults have been published. If these inadequacies in asthma management were corrected, using current treatment recommendations, the overall cost of asthma from both the community and patient perspective should fall. The situation requires increased use of preventative medications {sodium cromoglycate (cromolyn sodium) or inhaled corticosteroids}, more widespread use of written crisis plans, more proactive medical consultations (rather than reactive or urgent consultations), further expansion of asthma education programmes, and further education of medical practitioners about the optimum management of both long term asthma and the acute exacerbation of asthma in the patient's home, the doctor's office, the hospital emergency room and the hospital inpatient setting. The increased costs associated with these measures would be more than offset by reduced expenditure on bronchodilator drugs, less widespread use of nebulisers at home and in hospitals, reduced antibiotic usage, reduced need for expensive emergency medical care and particularly reduced utilisation of hospital resources. To ensure that resources are being directed into the most cost-effective areas of asthma care, clinical trials of asthma should include utilisation of healthcare resources as an outcome measure, and estimates of the costs of the treatment under study. In addition, since the intangible cost (quality of life) is one of the most important effects of treatment from the patient's perspective, this should be more widely used as an outcome measure in clinical trials. Ultimately, prevention of asthma is the long term goal. If the hypothesis that sensitisation to house dust mite in early infancy is a major contributor to the subsequent development of asthma, then prevention may require drastic and expensive changes to current housing.

The sleep patterns of a cohort of 83 Rett syndrome females were characterized using a sleep diary for 7 consecutive days and nights and compared with normative sleep data. The mean total sleep time of the cohort was 10.75 h, daytime sleep 0.77 h, sleep efficiency 89.7%, and sleep latency 0.52 h. When subjects were categorized according to age and Rett syndrome classification, there was no significant difference in their sleep characteristics. There was a significant difference in the percentage predicted total sleep time (P

For describing bronchial responsiveness, it has been suggested that the dose-response slope (DRS), which is the linear slope of the dose-response curve, is a more useful measure of severity than the provoking dose that causes a 20% fall in FEV1 (PD20FEV1). To determine the distribution of DRS measurements and their relation to respiratory illness in adults, we have reanalyzed data collected in 1981 from a random sample of the population of Busselton, Western Australia. We measured bronchial responsiveness to histamine by the rapid method and atopy by skin prick tests to 15 common allergens. Satisfactory bronchial challenge data were recorded for 858 subjects. Subjects were classified as having asthma symptoms by self-reported history or as having chronic airflow limitation by abnormality of lung function. In normal subjects, DRS values were symmetrically distributed on a logarithmic scale so that a value that represented abnormal responsiveness could be calculated. The dose-response slope had a significant independent association with past and current asthma symptoms, smoking history, sex, atopy, and FEV1/FVC ratio but not with chronic airflow limitation. In subjects in whom a PD20FEV1 could not be measured, the DRS had a significant relation to asthma symptoms, smoking history, and FEV1/FVC. Thus, DRS values, which could be obtained for most subjects, contributed additional information to PD20FEV1 values and discriminated more accurately between groups classified according to respiratory history. These data confirm that DRS values should be used in preference to PD20FEV1 values for describing the severity of bronchial responsiveness in populations.

Because there is no consensus definition of asthma for epidemiology, we have examined the reliability of a questionnaire and the effect of its mode of administration on classification of asthma in children. A symptom history questionnaire was parent self-administered and then readministered within three months by a nurse. The questions of diagnosed asthma, cumulative wheeze, and recent wheeze (wheeze in the previous 12 months) were more repeatable than questions of night cough, but 7 percent of children changed diagnosed asthma category, 13 percent changed cumulative wheeze category, and 9 percent changed recent wheeze category at second questionnaire. Because the numbers who changed from symptom positive to negative roughly equalled the changes from negative to positive, prevalence estimates were not affected. Methods of measuring asthma with greater precision are urgently needed. Because of reporting bias, epidemiologic information collected by current questionnaires should be treated with some caution. (Chest 1992; 102:153–57)

In a study in south-western Sydney, we examined asthma symptoms in a random sample of 4239 schoolchildren aged five-12 years. The prevalence of current wheeze and cough was 17.1% (95% CI 16.0–18.2%). Interviews were conducted with the parents of all 214 symptomatic children from two of the six schools. Only 60% of these children had ever been labelled as asthma, and only 20% were using appropriate asthma treatment. Fewer than 6% had ever had their airway function assessed. There was a socio-economic difference, with better levels of asthma recognition and management in children attending the school in the more aflluent region. The findings suggest that asthma recognition, assessment and management in the Australian community, as in New Zealand and the UK, may need to be improved. (Aust NZ J Med 1992; 22: 36–40.)