Differences in grass pollen allergen exposure across Australia

© 2015 The Authors © 2015 Public Health Association of Australia. Objective: Allergic rhinitis and allergic asthma are important chronic diseases posing serious public health issues in Australia with associated medical, economic, and societal burdens. Pollen are significant sources of clinically relevant outdoor aeroallergens, recognised as both a major trigger for, and cause of, allergic respiratory diseases. This study aimed to provide a national, and indeed international, perspective on the state of Australian pollen data using a large representative sample. Methods: Atmospheric grass pollen concentration is examined over a number of years within the period 1995 to 2013 for Brisbane, Canberra, Darwin, Hobart, Melbourne, and Sydney, including determination of the 'clinical' grass pollen season and grass pollen peak. Results: The results of this study describe, for the first time, a striking spatial and temporal variability in grass pollen seasons in Australia, with important implications for clinicians and public health professionals, and the Australian grass pollen-allergic community. Conclusions: These results demonstrate that static pollen calendars are of limited utility and in some cases misleading. This study also highlights significant deficiencies and limitations in the existing Australian pollen monitoring and data. Implications: Establishment of an Australian national pollen monitoring network would help facilitate advances in the clinical and public health management of the millions of Australians with asthma and allergic rhinitis

Ten-year prediction model for post-bronchodilator airflow obstruction and early detection of COPD: development and validation in two middle-aged population-based cohorts

Background Classifying individuals at high chronic obstructive pulmonary disease (COPD)-risk creates opportunities for early COPD detection and active intervention. Objective To develop and validate a statistical model to predict 10-year probabilities of COPD defined by post-bronchodilator airflow obstruction (post-BD-AO; forced expiratory volume in 1 s/forced vital capacity<5th percentile). Setting General Caucasian populations from Australia and Europe, 10 and 27 centres, respectively. Participants For the development cohort, questionnaire data on respiratory symptoms, smoking, asthma, occupation and participant sex were from the Tasmanian Longitudinal Health Study (TAHS) participants at age 41–45 years (n=5729) who did not have self-reported COPD/emphysema at baseline but had post-BD spirometry and smoking status at age 51–55 years (n=2407). The validation cohort comprised participants from the European Community Respiratory Health Survey (ECRHS) II and III (n=5970), restricted to those of age 40–49 and 50–59 with complete questionnaire and spirometry/smoking data, respectively (n=1407). Statistical method Risk-prediction models were developed using randomForest then externally validated. Results Area under the receiver operating characteristic curve (AUCROC) of the final model was 80.8% (95% CI 80.0% to 81.6%), sensitivity 80.3% (77.7% to 82.9%), specificity 69.1% (68.7% to 69.5%), positive predictive value (PPV) 11.1% (10.3% to 11.9%) and negative predictive value (NPV) 98.7% (98.5% to 98.9%). The external validation was fair (AUCROC 75.6%), with the PPV increasing to 17.9% and NPV still 97.5% for adults aged 40–49 years with ≥1 respiratory symptom. To illustrate the model output using hypothetical case scenarios, a 43-year-old female unskilled worker who smoked 20 cigarettes/day for 30 years had a 27% predicted probability for post-BD-AO at age 53 if she continued to smoke. The predicted risk was 42% if she had coexistent active asthma, but only 4.5% if she had quit after age 43. Conclusion This novel and validated risk-prediction model could identify adults aged in their 40s at high 10-year COPD-risk in the general population with potential to facilitate active monitoring/intervention in predicted ‘COPD cases’ at a much earlier age.Jennifer L Perret, Don Vicendese, Koen Simons, Debbie L Jarvis, Adrian J Lowe, Caroline J Lodge ... et al

Hospital characteristics, rather than surgical volume, predict length of stay following colorectal cancer surgery

OBJECTIVE: Length of hospital stay (LOS) is considered a vital component for successful colorectal surgery treatment. Evidence of an association between hospital surgery volume and LOS has been mixed. Data modelling techniques may give inconsistent results that adversely impact conclusions. This study applied techniques to overcome possible modelling drawbacks. METHOD: An additive quantile regression model formulated to isolate hospital contextual effects was applied to every colorectal surgery for cancer conducted in Victoria, Australia, between 2005 and 2015, involving 28,343 admissions in 90 Victorian hospitals. The model compared hospitals' operational efficiencies regarding LOS. RESULTS: Hospital LOS operational efficiencies for colorectal cancer surgery varied markedly between the 90 hospitals and were independent of volume. This result was adjusted for pertinent patient and hospital characteristics. CONCLUSION: No evidence was found that higher annual surgery volume was associated with lower LOS for patients undergoing colorectal cancer surgery. Our model showed strong evidence that differences in LOS efficiency between hospitals was driven by hospital contextual effects that were not predicted by provider volume. Further study is required to elucidate these inherent differences between hospitals. Implications for public health: Our model indicated improved efficiency would benefit the patient and medical system by lowering LOS and reducing expenditure by more than $3 million per year

Developing Fractional Exhaled Nitric Oxide Predicted and Upper Limit of Normal Values for a Disadvantaged Population

Background: Fractional exhaled nitric oxide (FENO), used as a biomarker, is influenced by several factors including ethnicity. Normative data are essential for interpretation, and currently single cutoff values are used in children and adults. Research Question: Accounting for factors that influence FENO, (1) what are appropriate predicted and upper limit of normal (ULN) FENO values in an underserved population (First Nations Australians), (2) how do these values compare with age-based interpretive guidelines, and (3) what factors influence FENO and what is the size of the effect? Study Design and Methods: FENO data of First Nations Australians (age < 16 years, n = 862; age ≥ 16 years, n = 348) were obtained. Medical history using participant questionnaires and medical records were used to define healthy participants. Flexible regression using spline functions, as used by the Global Lung Function Initiative, were used to generate predicted and ULN values. Results: Look-up tables for predicted and ULN values using age (4-76 years) and height (100-200 cm) were generated and are supplied with a calculator for clinician use. In healthy First Nations children (age < 18 years), ULN values ranged between 25 and 60 parts per billion (ppb) when considering only biologically plausible age and height combinations. For healthy adults, ULN values ranged between 39 and 88 ppb. Neither the current FENO interpretation guidelines, nor the currently recommended cutoff of 50 ppb for First Nations children 16 years of age or younger were appropriate for use in this cohort. Our modelling revealed that predicted and ULN values of healthy participants varied nonlinearly with age and height. Interpretation: Because single pediatric, adult, or all-age FENO cutoff values used by current interpretive guidelines to define abnormality fail to account for factors that modify FENO values, we propose predicted and ULN values for First Nations Australians 4 to 76 years of age. Creating age- and height-adjusted predicted and ULN values could be considered for other ethnicities.</p

Early childhood pneumonia is associated with reduced lung function and asthma in first nations australian children and young adults

Background: Some but not all previous studies report that pneumonia in children aged less than five years is associated with lower lung function and elevated risk of respiratory disease. To date, none have explored these associations in at-risk populations such as First Nations Australians, whose incidence of early childhood pneumonia is among the highest reported in the world. Methods: This cross-sectional study included 1276 First Nations Australian children/young adults aged 5–25 years recruited from regional/remote Queensland and Northern Territory communities and schools. Associations between pneumonia and both spirometry values and asthma were investigated using linear and logistic regression. Results: Early childhood pneumonia was associated with lower FEV1 and FVC Z-scores, but not FEV1/FVC% Z-scores, when occurring before age three (FEV1 β = −0.42, [95%CI −0.79, −0.04]; FVC β = −0.62, [95%CI −1.14, −0.09]), and between three and five years (β = −0.50, [95%CI −0.88, −0.12]; β = −0.63, [95%CI −1.17, −0.10]), compared to those who never had pneumonia. Similarly, pneumonia occurring when aged before age three years (OR = 3.68, 95%CI 1.96–6.93) and three to five years (OR = 4.81, 95%CI 1.46–15.8) was associated with increased risk of asthma in later childhood. Conclusions: Early childhood pneumonia is associated with lung function deficits and increased asthma risk in later childhood/early adulthood in First Nations Australians. The disproportionate impact of pneumonia on at-risk children must be addressed as a priority.</p

The effect of early childhood respiratory infections and pneumonia on lifelong lung function: a systematic review

Early childhood respiratory infections, including pneumonia, are an important global public health issue, with more than 40 million annual cases resulting in approximately 650 000 deaths. A growing number of published studies have examined the effects of early childhood lower respiratory tract infections (LRTIs) or pneumonia on lung function, particularly as part of large early-life exposure studies. To our knowledge, there is no published systematic review of these data. We searched PubMed, Embase, and Web of Science for studies published between database inception and May 12, 2022. Case-control, cohort, and cross-sectional studies were included if they reported forced expiratory volume in 1 s (FEV1) or forced vital capacity (FVC) values of participants older than 5 years. Article titles and abstracts were screened in Rayyan before retrieval, assessment, and data extraction of the full text. Primary outcome measures were differences in mean FEV1 or FVC values between exposed groups (ie, children aged ≤5 years with LRTIs) and non-exposed groups. This study is registered with PROSPERO, CRD42021265295. Database searches yielded 3070 articles, and 14 studies were included in this systematic review, providing a total of 23 276 participants, including 9969 children and 13 307 adults. Eight of 14 articles reported significant reductions in FEV1 values, and six of 12 studies reported reductions in FVC values in children and adults with a history of early childhood LRTIs or pneumonia, compared with unexposed controls (p<0·05). Most studies reporting reductions in lung function described deficits consistent with a restrictive spirometry pattern. Only two of 14 studies reported data from low-income and middle-income countries or disadvantaged populations in middle-income and high-income countries, and there were scarce data available on the effect of LRTI severity and recurrence on lung function. LRTIs in early childhood could be associated with a restrictive spirometry pattern in later childhood and adulthood. Data are needed from low-income and middle-income nations, and from disadvantaged populations in middle-income and high-income countries in which early childhood respiratory infection burden is disproportionately high. Data are also needed on the effect of LRTI severity and recurrence on future lung function.</p

Effect of season of birth on cord blood IgE and IgE at birth: A systematic review and meta-analysis.

BACKGROUND: Elevated cord blood IgE is important on the pathway to allergic disease. The association between season of birth and infant cord blood IgE is not well-established. Study findings differ on which birth season is associated with higher cord blood IgE risk and its magnitude. We conducted a systematic review and meta-analysis of studies on season of birth and cord blood IgE. METHODS: We searched Medline, Web of Science, Scopus and ProQuest Health databases, and reviewed reference lists of articles that met the inclusion criteria. All included studies measured IgE as a binary variable using various cut-off values. We performed multivariate-random-effects meta-analysis to handle an exposure with multiple categories of Season of Birth. RESULTS: Our search identified 275 records and 10 had sufficient data to be included in a meta-analysis. Relative to summer, winter birth had the greatest odds of high IgE (&ge; 0.1IU/ml), meta-analysis OR = 1.24 (95%CI: 1.01-1.52). A similar OR, was found for IgE &ge; 0.5 IU/ml, OR = 1.30 (95%CI: 0.99-1.71). CONCLUSIONS: A winter season of birth was associated with statistically significant higher odds of elevated cord blood IgE at cut-off &ge; 0.1IU/ml but borderline at cut-off &ge; 0.5IU/ml. This winter effect is likely to be a marker for a range of other environmental exposures during specific stages of pregnancy, such as aeroallergen exposures, maternal infections and vitamin D levels. Further research is required to support our finding and to identify the exact mechanisms that lead to the winter season of birth effect on circulating IgE levels, as this may have implications for allergic disease prevention

Evaluation of the performance of short-term curated daily airborne grass pollen forecasts in diverse biogeographical regions during the AusPollen Partnership project 2016–2020

When providing pollen forecasts to the community, there is a need to verify the accuracy of curated forecasts, but evaluation is not routinely reported. This study of the AusPollen Partnership compared multi-category grass pollen forecasts for up to six days ahead with daily airborne grass pollen concentrations measured in Brisbane, Canberra, Melbourne, and Sydney, Australia during four pollen seasons from 2016 to 2020. The accuracy of categorical grass pollen forecasts predicting grass pollen concentrations in the high and greater, or moderate and greater categories, were assessed as often applied in meteorology using Gerrity scores, equitable threat scores, false alarm ratios, success ratios, and probability of detection of correct category. The skill of grass pollen forecasts curated by aerobiologists were compared with two retrospectively calculated naïve reference forecast methods; climatology and persistence. For Brisbane and Melbourne, high or greater grass pollen levels occurred on average 32% and 22% of days, whereas for Canberra and Sydney, there were few high days, but moderate or greater pollen levels occurred on average 26% and 19% of days, respectively. Average annual Gerrity scores for curated forecasts of high or greater improved with experience from 0.20 to 0.66 in Brisbane, and from 0.39 to 0.55 in Melbourne between 2016 and 2019. Average Gerrity Scores for moderate or greater categories in Sydney were 0.45 and 0.43 in 2016 and 2018 respectively, and in Canberra were 0.34 and 0.41, in the same years. The skill of curated forecasts was usually better than persistence forecasts, but the accuracy of the curated forecasts decreased with longer lead times. Although persistence grass pollen forecasts consistently performed better than climatologies, persistence depends on previous day pollen concentrations being available. Short-term curated daily grass pollen forecasts of the AusPollen Partnership offer useful information for people with allergic rhinitis and asthma, to help facilitate behavioural change and reduce the health burden. There is a need in Australia to extend local pollen records through sustained pollen monitoring to track climate-related changes as well as improve reliability of daily pollen forecasts. Globally, continued evaluation will enable reporting of accurate pollen forecasts to community, clinicians and government stakeholders