Jennifer Peat

Prevalence of atopy, asthma symptoms and diagnosis, and the management of asthma: comparison of an affluent and a non-affluent country

BACKGROUND The prevalence of childhood asthma and of atopy varies widely between countries. However, few studies have compared the pattern of diagnosis and management of asthma, or the role of atopy in predisposing to asthma between a less affluent country and a more affluent country. The aim of this study was to compare the prevalence of symptoms, diagnosis, and management of asthma, and the prevalence of atopy as measured by skin prick tests in Nigeria and Australia using a standardised methodology. METHODS Respiratory history was collected using a validated questionnaire administered to parents, and atopy was measured with skin prick tests in 654 Australian and 566 Nigerian children aged 8–11 years (70% consent rate in Australia, 60% in Nigeria). RESULTS Wheeze and persistent cough were less prevalent in Nigeria (10.2% and 5.1%, respectively) than in Australia (21.9% and 9.6%, respectively), caused less morbidity, and were less likely to be labelled or treated as asthma than in Australia. There was no significant difference in the overall prevalence of atopy between the two countries (Australia 32.5%, Nigeria 28.2%). Atopy was a strong risk for wheeze in both countries (odds ratio (OR) 3.4 (95% CI 2.3 to 5.1) in Australia, 1.8 (95% CI 1.0 to 3.3) in Nigeria), especially atopy to house dust mites (OR 3.1 (95% CI 2.1 to 4.7) in Australia, 2.4 (95% CI 1.3 to 4.3) in Nigeria). CONCLUSION Although there was a similar prevalence of atopy in both countries, Australian children had a higher prevalence of asthma symptoms. Further studies are needed to determine why atopic children in Australia are more at risk of developing asthma. Such studies will have important implications for the prevention of asthma.

Mite allergen (Der p 1) concentration in houses and its relation to the presence and severity of asthma in a population of Sydney schoolchildren

House dust mite (HDM) allergen exposure and its relation to HDM allergy and asthma was assessed in a case-control study conducted over three seasons in 74 Sydney schoolchildren, 33 of whom were allergic to HDM and 12 of whom had current asthma. In each season histamine inhalation tests and skin prick tests were performed, symptom questionnaires were administered, and dust samples were collected. The mean concentrations of HDM allergen (in micrograms of Der p 1 per gram of fine dust) were: bed, 38.9 (95% confidence interval [CI], 31.8 to 47.5); bedroom floor, 22.4 (95% CI, 18.3 to 27.5); and lounge room floor, 13.7 (95% CI, 10.7 to 17.6). The mean of the highest allergen concentration in each house was 51.0 (95% CI, 43.2 to 60.1). All but two subjects had at least one site in all seasons with an HDM allergen concentration greater than 10 micrograms/gm, the proposed threshold for asthma symptoms. Subjects with allergy to HDM, symptoms of asthma, or airway hyperresponsiveness did not have higher HDM allergen concentrations in their house. In this study we were unable to test hypotheses concerning proposed thresholds for risk of sensitization and for risk of asthma symptoms because virtually all subjects were exposed to HDM allergen levels above the proposed thresholds.

Association between infant feeding patterns and diarrhoeal and respiratory illness: A cohort study in Chittagong, Bangladesh

BackgroundIn developing countries, infectious diseases such as diarrhoea and acute respiratory infections are the main cause of mortality and morbidity in infants aged less than one year. The importance of exclusive breastfeeding in the prevention of infectious diseases during infancy is well known. Although breastfeeding is almost universal in Bangladesh, the rates of exclusive breastfeeding remain low. This cohort study was designed to compare the prevalence of diarrhoea and acute respiratory infection (ARI) in infants according to their breastfeeding status in a prospective cohort of infants from birth to six months of age.MethodsA total of 351 pregnant women were recruited in the Anowara subdistrict of Chittagong. Breastfeeding practices and the 7-day prevalence of diarrhoea and ARI were recorded at monthly home visits. Prevalences were compared using chi-squared tests and logistic regression.ResultsA total of 272 mother-infant pairs completed the study to six months. Infants who were exclusively breastfed for six months had a significantly lower 7-day prevalence of diarrhoea [AOR for lack of EBF = 2.50 (95%CI 1.10, 5.69), p = 0.03] and a significantly lower 7-day prevalence of ARI [AOR for lack of EBF = 2.31 (95%CI 1.33, 4.00), p < 0.01] than infants who were not exclusively breastfed. However, when the association between patterns of infant feeding (exclusive, predominant and partial breastfeeding) and illness was investigated in more detail, there was no significant difference in the prevalence of diarrhoea between exclusively [6.6% (95% CI 2.8, 10.4)] and predominantly breastfed infants [3.7% (95% CI 0.09, 18.3), (p = 0.56)]. Partially breastfed infants had a higher prevalence of diarrhoea than the others [19.2% (95% CI 10.4, 27.9), (p = 0.01)]. Similarly, although there was a large difference in prevalence in acute respiratory illness between exclusively [54.2% (95%CI 46.6, 61.8)] and predominantly breastfed infants [70.4% (95%CI 53.2, 87.6)] there was no significant difference in the prevalence (p = 0.17).ConclusionThe findings suggest that exclusive or predominant breastfeeding can reduce rates of morbidity significantly in this region of rural Bangladesh.

The validity and reliability of a home environment preschool-age physical activity questionnaire (Pre-PAQ)

BackgroundThere is a need for valid population level measures of physical activity in young children. The aim of this paper is to report the development, and the reliability and validity, of the Preschool-age Childrens Physical Activity Questionnaire (Pre-PAQ) which was designed to measure activity of preschool-age children in the home environment in population studies.MethodsPre-PAQ was completed by 103 families, and validated against accelerometry for 67 children (mean age 3.8 years, SD 0.74; males 53%). Pre-PAQ categorizes activity into five progressive levels (stationary no movement, stationary with limb or trunk movement, slow, medium, or fast-paced activity). Pre-PAQ Levels 1-2 (stationary activities) were combined for analyses. Accelerometer data were categorized for stationary, sedentary (SED), non-sedentary (non-SED), light (LPA), moderate (MPA) and vigorous (VPA) physical activity using manufacturers advice (stationary) or the cut-points described by Sirard et al and Reilly et al. Bland-Altman methods were used to assess agreement between the questionnaire and the accelerometer measures for corresponding activity levels. Reliability of the Pre-PAQ over one week was determined using intraclass correlations (ICC) or kappa (κ) values and percentage of agreement of responses between the two questionnaire administrations.ResultsPre-PAQ had good agreement with LPA (mean difference 1.9 mins.day-1) and VPA (mean difference -4.8 mins.day-1), was adequate for stationary activity (mean difference 7.6 mins.day-1) and poor for sedentary activity, whether defined using the cut-points of Sirard et al (mean difference -235.4 mins.day-1) or Reilly et al (mean difference -208.6 mins.day-1) cut-points. Mean difference between the measures for total activity (i.e. Reillys non-sedentary or Sirards LMVPA) was 20.9 mins.day-1 and 45.2 mins.day-1. The limits of agreement were wide for all categories. The reliability of Pre-PAQ question responses ranged from 0.31-1.00 (ICC (2, 1)) for continuous measures and 0.60-0.97 (κ) for categorical measures.ConclusionsPre-PAQ has acceptable validity and reliability and appears promising as a population measure of activity behavior but it requires further testing on a more broadly representative population to affirm this. Pre-PAQ fills an important niche for researchers to measure activity in preschool-age children and concurrently to measure parental, family and neighborhood factors that influence these behaviors.

Statistics workbook for evidence-based healthcare

Contents . Foreword . By Virginia A. Moyer . Introduction. Overview . UNIT 1 Hypothesis testing and estimation. UNIT 2 Incidence and prevalence rates . UNIT 3 Comparing proportions . UNIT 4 Relative risk and odds ratio . UNIT 5 Clinical trials . UNIT 6 Comparing mean values . UNIT 7 Correlation and regression . UNIT 8 Follow-up studies . UNIT 9 Survival analyses . UNIT 10 Diagnostic and screening statistics. Answers. Glossary. Index

Improving paediatric asthma outcomes in primary health care: a randomised controlled trial

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.

Association between der p 1 concentration and peak expiratory flow rate in children with wheeze : A longitudinal analysis

BACKGROUND House dust mite (HDM) allergen exposure has been well documented as an environmental cause of airway hyperresponsiveness (AHR) and asthma symptoms. The relationship between asthma morbidity and exposure to low concentrations of HDM allergen suggests that there may be no safe exposure threshold to HDM allergen. OBJECTIVE We aimed to investigate the associations between Der p 1 in bedding and lung function in 30 children with a history of wheezing in a longitudinal study. METHODS After a cross-sectional study of school children, which included histamine challenge for AHR and skin testing for dust mite atopy, we made repeated measurements of HDM allergens in children with a history of wheeze over a 12-month period. These children also kept a daily asthma diary in which they recorded their peak expiratory flow rates (PEFRs). We used a repeated measures model to determine the association between PEFR and HDM allergen concentration. RESULTS There was a significant association between PEFRs and HDM allergen concentration (beta-coefficient = -14.17, P = .0024) in children with HDM atopy. An association was not found in children without HDM atopy. CONCLUSIONS These findings support the hypothesis that HDM allergens have an adverse effect on the lung function of children with wheeze and highlight the importance of maintaining low dust mite allergen levels throughout the year in the home environment of children sensitized to HDMs.

Early predictors of asthma.

A number of recent cohort and cross-sectional studies have contributed substantial knowledge to factors that influence the early development of asthma. Here, we summarize the recent evidence for the role of early life events such as prenatal factors, infections, diet and allergen exposure, and discuss the implications for future preventative strategies.

2. Getting Started

Every year The Academy of Motion Picture Arts and Sciences runs a competition for screenplay writers, the Nicholl Fellowships in Screenwriting. Fulllength feature film screenplays are submitted (for a fee). You can win money but, more importantly, placing in the competition will make agents take notice. The Academy recommends a particular format which this class file attempts to duplicate, using a .pdf available from The Academy website as the model. This format has various functions, amongst which is a gate-keeping function to show you have at least a first idea. It also gives readers a better chance of assessing how long, in filmic terms, your screenplay would be. Formatted along the lines recommended, you should aim to have your screenplay in the region of 120 pages long. Although they say A4 paper is acceptable, it is widely held that you severely handicap yourself if you don’t use American 8.5” by 11” Letter size paper. I have a ream on my lap as I type: 20 pound, 106 bright, acid free. My sister brought it from America for me—it’s very expensive to buy outside the US and not easy to find. One might imagine it’s at the photocopy stage that dealing with A4 in America becomes a nuisance—one more reason to put your magnum opus to the bottom of the pile. Of course, if you didn’t know this already you likely need to do some serious reading and research before you start writing. I guess trying to understand what’s going on here is a start. The format specifications are pretty straightforward. You’ll have to believe me when I say it wasn’t quite so straightforward for me to start from a minimal understanding of TEX and LTEX2ε to a usable .dtx file. This is an attempt to turn TEX into a typewriter emulator. A crazy idea— which is why it appealed to me, obviously. Fortunately I’m easily entertained. I hope screenplay.dtx proves of use (and instruction) to others as it has to me. Anyhoo, on with the show. . .