Can We Use Lung Function Thresholds and Respiratory Symptoms to Identify Pre-Chronic Obstructive Pulmonary Disease? A Prospective, Population-based Cohort Study.

Rationale: The term "pre-chronic obstructive pulmonary disease" ("pre-COPD") refers to individuals at high risk of developing COPD who do not meet conventional spirometric criteria for airflow obstruction. New approaches to identifying these individuals are needed, particularly in younger populations. Objectives: To determine whether lung function thresholds and respiratory symptoms can be used to identify individuals at risk of developing COPD. Methods: The Tasmanian Longitudinal Health Study comprises a population-based cohort first studied in 1968 (at age 7 yr). Respiratory symptoms, pre- and post-bronchodilator (BD) spirometry, diffusing capacity, and static lung volumes were measured in a subgroup at age 45, and the incidence of COPD was assessed at age 53. For each lung function measure, z-scores were calculated using Global Lung Function Initiative references. The optimal threshold for best discrimination of COPD incidence was determined by the unweighted Youden index. Measurements and Main Results: Among 801 participants who did not have COPD at age 45, the optimal threshold for COPD incidence by age 53 was pre-BD FEV1/FVC z-score less than -1.264, corresponding to the lowest 10th percentile. Those below this threshold had a 36-fold increased risk of developing COPD over an 8-year follow-up period (risk ratio, 35.8; 95% confidence interval, 8.88 to 144), corresponding to a risk difference of 16.4% (95% confidence interval, 3.7 to 67.4). The sensitivity was 88%, and the specificity was 87%. Positive and negative likelihood ratios were 6.79 and 0.14, respectively. Respiratory symptoms, post-BD spirometry, diffusing capacity, and static lung volumes did not improve on the classification achieved by pre-BD FEV1/FVC alone. Conclusions: This is the first study, to our knowledge, to evaluate the discriminatory accuracy of spirometry, diffusing capacity, and static lung volume thresholds for COPD incidence in middle-aged adults. Our findings support the inclusion of pre-BD spirometry in the physiological definition of pre-COPD and indicate that pre-BD FEV1/FVC at the 10th percentile accurately identifies individuals at high risk of developing COPD in community-based settings.

Associations of early life and childhood risk factors with obstructive sleep apnoea in middle-age.

BACKGROUND AND OBJECTIVE: Early-life risk factors for obstructive sleep apnoea (OSA) are poorly described, yet this knowledge may be critical to inform preventive strategies. We conducted the first study to investigate the association between early-life risk factors and OSA in middle-aged adults. METHODS: Data were from population-based Tasmanian Longitudinal Health Study cohort (n = 3550) followed from 1st to 6th decades of life. Potentially relevant childhood exposures were available from a parent-completed survey at age 7-years, along with previously characterized risk factor profiles. Information on the primary outcome, probable OSA (based on a STOP-Bang questionnaire cut-off ≥5), were collected when participants were 53 years old. Associations were examined using logistic regression adjusting for potential confounders. Analyses were repeated using the Berlin questionnaire. RESULTS: Maternal asthma (OR = 1.5; 95% CI 1.1-2.0), maternal smoking (OR = 1.2; 1.05, 1.5), childhood pleurisy/pneumonia (OR = 1.3; 1.04, 1.7) and frequent bronchitis (OR = 1.2; 1.01, 1.5) were associated with probable OSA. The risk-factor profiles of 'parental smoking' and 'frequent asthma and bronchitis' were also associated with probable OSA (OR = 1.3; 1.01, 1.6 and OR = 1.3; 1.01-1.9, respectively). Similar associations were found for Berlin questionnaire-defined OSA. CONCLUSIONS: We found novel temporal associations of maternal asthma, parental smoking and frequent lower respiratory tract infections before the age of 7 years with adult OSA. While determination of their pathophysiological and any causal pathways require further research, these may be useful to flag the risk of OSA within clinical practice and create awareness and vigilance among at-risk groups.

Longitudinal Asthma Phenotypes from Childhood to Middle-Age: A Population-based Cohort Study.

Rationale: Asthma is a heterogeneous condition, and longitudinal phenotyping may provide new insights into the origins and outcomes of the disease. Objectives: We aimed to characterize the longitudinal phenotypes of asthma between the first and sixth decades of life in a population-based cohort study. Methods: Respiratory questionnaires were collected at seven time points in the TAHS (Tasmanian Longitudinal Health Study) when participants were aged 7, 13, 18, 32, 43, 50, and 53 years. Current-asthma and ever-asthma status was determined at each time point, and group-based trajectory modeling was used to characterize distinct longitudinal phenotypes. Linear and logistic regression models were fitted to investigate associations of the longitudinal phenotypes with childhood factors and adult outcomes. Measurements and Main Results: Of 8,583 original participants, 1,506 had reported ever asthma. Five longitudinal asthma phenotypes were identified: early-onset adolescent-remitting (40%), early-onset adult-remitting (11%), early-onset persistent (9%), late-onset remitting (13%), and late-onset persistent (27%). All phenotypes were associated with chronic obstructive pulmonary disease at age 53 years, except for late-onset remitting asthma (odds ratios: early-onset adolescent-remitting, 2.00 [95% confidence interval (CI), 1.13-3.56]; early-onset adult-remitting, 3.61 [95% CI, 1.30-10.02]; early-onset persistent, 8.73 [95% CI, 4.10-18.55]; and late-onset persistent, 6.69 [95% CI, 3.81-11.73]). Late-onset persistent asthma was associated with the greatest comorbidity at age 53 years, with increased risk of mental health disorders and cardiovascular risk factors. Conclusions: Five longitudinal asthma phenotypes were identified between the first and sixth decades of life, including two novel remitting phenotypes. We found differential effects of these phenotypes on risk of chronic obstructive pulmonary disease and nonrespiratory comorbidities in middle age.

Life course BMI trajectories from childhood to mid-adulthood are differentially associated with anxiety and depression outcomes in middle age.

BACKGROUND/OBJECTIVE: Obesity is a risk factor for multimorbidity, including depression and possibly anxiety. However, it is currently unclear how patterns of change in BMI over the life course differentially influence the magnitude in risk of depression and anxiety in mid-adulthood. We aimed to examine associations between BMI trajectories from childhood to adulthood and the risk of depression and anxiety in middle age. METHODS: In the Tasmanian Longitudinal Health Study (n = 2416), five distinct BMI trajectories were previously defined from age 5 to 45 years using group-based modelling. At age 53, current depression and anxiety were assessed using the Patient Health Questionnaire and the Generalized Anxiety Disorder scale, respectively. Logistic regression models adjusted for potential confounders estimated associations between BMI trajectories and these outcomes. RESULTS: Those belonging to the child average-increasing (OR = 2.24; 95%CI: 1.24, 4.06) and persistently high (OR = 2.64; 1.26, 5.52) trajectories were more likely to have depression in middle age, compared to the persistently average trajectory. However, the odds of experiencing greater severity of depressive symptoms was highest in the child average-increasing group (OR = 2.36; 1.59, 3.49). Despite finding no evidence of association between BMI trajectories and current anxiety, we observed less severe symptoms in the child high-decreasing trajectory (OR = 0.68; 0.51, 0.91). CONCLUSION: We found an increased risk of depression in middle age among individuals with a persistently high BMI from childhood to mid-adulthood and individuals with an average BMI in childhood which then increased consistently throughout adulthood. Encouragingly, resolving childhood adiposity by adulthood was associated with lesser anxiety symptoms. Taken together, these findings highlight the need to target mental health screening and treatment towards high-risk BMI trajectory groups and the importance of early interventions to prevent and resolve excess weight.

Exploration of associations between occupational exposures and current adult eczema.

OBJECTIVES: There is a scarcity of evidence on occupational exposures that may increase eczema in adults. We aimed to investigate potential associations between occupational exposures and eczema in middle-aged adults. METHODS: A lifetime work history calendar was collected from the Tasmanian Longitudinal Health Study participants when they were at age 53. Their work history was collated with the occupational asthma-specific job exposure matrix to define ever-exposure and cumulative exposure unit-years since no eczema job exposure matrix is available. Eczema was determined using the report of flexural rash that was coming and going for at least 6 months in the last 12 months. Skin prick tests were used to further subgroup eczema and atopic eczema (AE) or non-AE (NAE). Logistic and multinomial regression models were used to investigate the associations. RESULTS: Eczema prevalence was 9.1%. Current occupational exposure to animals (adjusted OR, aOR=3.06 (95% CI 1.43 to 6.58)), storage mites (aOR=2.96 (95% CI 1.38 to 6.34)) and endotoxin (aOR=1.95 (95% CI 1.04 to 3.64)) were associated with increased risk of current eczema. Furthermore, increased odds of NAE were associated with current exposure to animals (aOR=5.60 (95% CI 1.45 to 21.7)) and storage mites (aOR=5.63 (95% CI 1.45 to 21.9)). Current exposures to isocyanates (aOR=5.27 (95% CI 1.17 to 23.7)) and acrylates (aOR=8.41 (95% CI 1.60 to 44.3)) were associated with AE. There was no evidence of associations between cumulative exposures and eczema prevalence. Cumulative exposure to metalworking fluids (aOR=1.10 (95% CI 1.01 to 1.22)) was associated with NAE and acrylates (aOR=1.24 (95% CI 1.04 to 1.46)) with AE. CONCLUSIONS: In this exploratory assessment, multiple occupational exposures were associated with current eczema in middle-aged adults. Raising awareness and limiting these exposures during an individual's productive working life will likely have various health benefits, including reducing eczema prevalence.

The relative contribution of co-morbidities to health-related quality of life of people with idiopathic pulmonary fibrosis using the Assessment of Quality of Life-8-Dimension multi-attribute utility instrument.

PURPOSE: Little is known about the impact of co-morbidities on health-related quality of life (HRQoL) for people with idiopathic pulmonary fibrosis (IPF). We aimed to investigate the relative contribution of co-morbidities to HRQoL of people with IPF. METHODS: N = 157 participants were recruited from the Australian IPF Registry (AIPFR). Health state utilities (HSUs), and the super-dimensions of physical and psychosocial scores were measured using the Assessment of Quality of Life-8-Dimensions (AQoL-8D). The impact of co-morbidities on HRQoL was investigated using linear regression and general dominance analyses. RESULTS: A higher number of co-morbidities was associated with lower HSUs (p trend = 0.002). Co-morbidities explained 9.1% of the variance of HSUs, 16.0% of physical super-dimensional scores, and 4.2% of psychosocial super-dimensional scores. Arthritis was associated with a significant reduction on HSUs (ß = - 0.09, 95% confidence interval [CI] - 0.16 to - 0.02), largely driven by reduced scores on the physical super-dimension (ß = - 0.13, 95% CI - 0.20 to - 0.06). Heart diseases were associated with a significant reduction on HSUs (ß = - 0.09, 95% CI - 0.16 to - 0.02), driven by reduced scores on physical (ß = - 0.09, 95% CI - 0.16 to - 0.02) and psychosocial (ß = -0.10, 95% CI - 0.17 to - 0.02) super-dimensions. CONCLUSIONS: Co-morbidities significantly impact HRQoL of people with IPF, with markedly negative impacts on their HSUs and physical health. A more holistic approach to the care of people with IPF is important as better management of these co-morbidities could lead to improved HRQoL in people with IPF.

Assessment of health-related quality of life in Australian patients with idiopathic pulmonary fibrosis: a comparison of the EQ-5D-5L and the AQoL-8D.

PURPOSE: Idiopathic pulmonary fibrosis (IPF) is a progressive and debilitating chronic lung disease with a high symptom burden, which has a substantial impact on health-related quality of life (HRQoL). Our study aimed to assess the suitability of the EuroQol five-dimension (EQ-5D-5L) and the Assessment of Quality of Life- eight-dimension (AQoL-8D) questionnaires in measuring HRQoL as health state utility values (HSUVs) in an Australian IPF cohort. METHODS: Data for estimation of health state utility values (HSUVs) were collected from participants of the Australian IPF Registry (AIPFR) using self-administered surveys which included the EQ-5D-5L and the AQoL-8D. Data on lung function and disease specific HRQoL instruments were collected from the AIPFR. Performance of the two instruments was evaluated based on questionnaire practicality, agreement between the two instruments and test performance (internal and construct validity). RESULTS: Overall completion rates for the EQ-5D-5L and AQoL-8D were 96% and 85%, respectively. Mean (median) HSUVs were 0.65 (0.70) and 0.69 (0.72) for the EQ-5D-5L and AQoL-8D, respectively. There was reasonable agreement between the two instruments based on the Bland-Altman plot mean difference (-0.04) and intraclass correlation coefficient (0.84), however there were some fundamental differences. A larger range of values was observed with the EQ-5D-5L (-0.57-1.00 vs 0.16-1.00). The EQ-5D-5L had a greater divergent sensitivity and efficacy in relation to assessing HSUVs between clinical groupings. The AQoL-8D ,however, had a higher sensitivity to measure psychosocial aspects of HRQoL in IPF. CONCLUSION: The EQ-5D-5L demonstrated superior performance when compared to AQoL-8D in persons with IPF. This may be attributable to the high symptom burden which is physically debilitating to which the EQ-5D-5L may be more sensitive.

Small for gestational age is associated with reduced lung function in middle age: A prospective study from first to fifth decade of life.

BACKGROUND AND OBJECTIVE: The association between birth weight, particularly relative to gestational age, and adult lung function is uncertain. We investigated the associations between birth weight relative to gestational age and measures of lung function in middle age, and mediation of these associations by adult height. METHODS: Participants in the Tasmanian Longitudinal Health Study who had both known birth weight and lung function assessment at age 45 years were included (n = 849). Linear regression models were fitted to investigate the association between small for gestational age and birth weight with post-bronchodilator lung function measures (forced expiratory volume in 1 second [FEV1 ], forced vital capacity [FVC], FEV1 /FVC, diffusing capacity for carbon monoxide [DL co], residual volume [RV] and total lung capacity [TLC]), adjusting for potential confounders. The contribution of adult height as a mediator of these associations was investigated. RESULTS: Compared with infants born with normal weight for gestational age, those born small for gestational age had reduced FEV1 (coefficient: -191 ml [95%CI: -296, -87]), FVC (-205 ml [-330, -81]), TLC (-292 ml [-492, -92]), RV (-126 ml [-253, 0]) and DL co (-0.42 mmol/min/kPa [-0.79, -0.041]) at age 45 years. However, they had comparable FEV1 /FVC. For every 1 kg increase in birth weight, lung function indices increased by an average of 117 ml (95%CI: 40, 196) for FEV1 , 124 ml (30, 218) for FVC, 215 ml (66, 365) for TLC and 0.36 mmol/min/kPa (0.11, 0.62) for DL co, independent of gestational age, but again not for FEV1 /FVC. These associations were significantly mediated by adult height (56%-90%). CONCLUSION: Small for gestational age was associated with reduced lung function that is likely due to smaller lungs with little evidence of any specific parenchymal impairment.

Long-term exposure to low concentrations of air pollution and decline in lung function in people with idiopathic pulmonary fibrosis: Evidence from Australia.

BACKGROUND AND OBJECTIVE: Little is known about the association between ambient air pollution and idiopathic pulmonary fibrosis (IPF) in areas with lower levels of exposure. We aimed to investigate the impact of air pollution on lung function and rapid progression of IPF in Australia. METHODS: Participants were recruited from the Australian IPF Registry (n = 570). The impact of air pollution on changes in lung function was assessed using linear mixed models and Cox regression was used to investigate the association with rapid progression. RESULTS: Median (25th-75th percentiles) annual fine particulate matter (<2.5 µm, PM2.5 ) and nitrogen dioxide (NO2 ) were 6.8 (5.7, 7.9) µg/m3 and 6.7 (4.9, 8.2) ppb, respectively. Compared to living more than 100 m from a major road, living within 100 m was associated with a 1.3% predicted/year (95% confidence interval [CI] -2.4 to -0.3) faster annual decline in diffusing capacity of the lungs for carbon monoxide (DLco). Each interquartile range (IQR) of 2.2 µg/m3 increase in PM2.5 was associated with a 0.9% predicted/year (95% CI -1.6 to -0.3) faster annual decline in DLco, while there was no association observed with NO2 . There was also no association between air pollution and rapid progression of IPF. CONCLUSION: Living near a major road and increased PM2.5 were both associated with an increased rate of annual decline in DLco. This study adds to the evidence supporting the negative effects of air pollution on lung function decline in people with IPF living at low-level concentrations of exposure.

Inhaled corticosteroids with combination inhaled long-acting beta2-agonists and long-acting muscarinic antagonists for chronic obstructive pulmonary disease.

BACKGROUND: Management of chronic obstructive pulmonary disease (COPD) commonly involves a combination of long-acting bronchodilators including beta2-agonists (LABA) and muscarinic antagonists (LAMA). LABA and LAMA bronchodilators are now available in single-combination inhalers. In individuals with persistent symptoms or frequent exacerbations, inhaled corticosteroids (ICS) are also used with combination LABA and LAMA inhalers. However, the benefits and risks of adding ICS to combination LABA/LAMA inhalers as a triple therapy remain unclear. OBJECTIVES: To assess the effects of adding an ICS to combination LABA/LAMA inhalers for the treatment of stable COPD. SEARCH METHODS: We searched the Cochrane Airways Group Register of Trials, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, and Embase up to 30 November 2022. We also searched ClinicalTrials.gov and the WHO ICTRP up to 30 November 2022. SELECTION CRITERIA: We included parallel-group randomised controlled trials of three weeks' duration or longer that compared the treatment of stable COPD with ICS in addition to combination LABA/LAMA inhalers against combination LABA/LAMA inhalers alone. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. The primary outcomes were acute exacerbations of COPD, respiratory health-related quality of life, pneumonia and other serious adverse events. The secondary outcomes were symptom scores, lung function, physical capacity, and mortality. We used GRADE to assess certainty of evidence for studies that contributed data to our prespecified outcomes. MAIN RESULTS: Four studies with a total of 15,412 participants met the inclusion criteria. The mean age of study participants ranged from 64.4 to 65.3 years; the proportion of female participants ranged from 28% to 40%. Most participants had symptomatic COPD (COPD Assessment Test Score ≥ 10) with severe to very severe airflow limitation (forced expiratory volume in one second (FEV1) < 50% predicted) and one or more moderate-to-severe COPD exacerbations in the last 12 months. Trial medications differed amongst studies. The duration of follow-up was 52 weeks in three studies and 24 weeks in one study. We assessed the risk of selection, performance, and detection bias to be low in the included studies; one study was at high risk of attrition bias, and one study was at high risk of reporting bias. Triple therapy may reduce rates of moderate-to-severe COPD exacerbations compared to combination LABA/LAMA inhalers (rate ratio (RR) 0.74, 95% confidence interval (CI) 0.67 to 0.81; n = 15,397; low-certainty evidence). Subgroup analysis stratifying by blood eosinophil counts showed there may be a greater reduction in rate of moderate-to-severe COPD exacerbations with triple therapy in participants with high-eosinophils (RR 0.67, 95% CI 0.60 to 0.75) compared to low-eosinophils (RR 0.87, 95% CI 0.81 to 0.93) (test for subgroup differences: P < 0.01) (high/low cut-offs: 150 eosinophils/µL in three studies; 200 eosinophils/µL in one study). However, moderate-to-substantial heterogeneity was observed in both high- and low-eosinophil subgroups. These subgroup analyses are observational by nature and thus results should be interpreted with caution. Triple therapy may be associated with reduced rates of severe COPD exacerbations (RR 0.75, 95% CI 0.67 to 0.84; n = 14,131; low-certainty evidence). Triple therapy improved health-related quality of life assessed using the St George's Respiratory Questionnaire (SGRQ) by the minimal clinically important difference (MCID) threshold (4-point decrease) (35.3% versus 42.4%, odds ratio (OR) 1.35, 95% CI 1.26 to 1.45; n = 14,070; high-certainty evidence). Triple therapy may result in fewer symptoms measured using the Transition Dyspnoea Index (TDI) (OR 1.33, 95% CI 1.13 to 1.57; n = 3044; moderate-certainty evidence) and improved lung function as measured by change in trough FEV1 (mean difference 38.68 mL, 95% CI 22.58 to 54.77; n = 11,352; low-certainty evidence). However, these benefits fell below MCID thresholds for TDI (1-unit decrease) and trough FEV1 (100 mL), respectively. Triple therapy is probably associated with a higher risk of pneumonia as a serious adverse event compared to combination LABA/LAMA inhalers (3.3% versus 1.9%, OR 1.74, 95% CI 1.39 to 2.18; n = 15,412; moderate-certainty evidence). In contrast, all-cause serious adverse events may be similar between groups (19.7% versus 19.7%, OR 0.95, 95% CI 0.87 to 1.03; n = 15,412; low-certainty evidence). All-cause mortality may be lower with triple therapy (1.4% versus 2.0%, OR 0.70, 95% CI 0.54 to 0.90; n = 15,397; low-certainty evidence). AUTHORS' CONCLUSIONS: The available evidence suggests that triple therapy may reduce rates of COPD exacerbations (low-certainty evidence) and results in an improvement in health-related quality of life (high-certainty evidence) compared to combination LABA/LAMA inhalers, but probably confers an increased pneumonia risk as a serious adverse event (moderate-certainty evidence). Triple therapy probably improves respiratory symptoms and may improve lung function (moderate- and low-certainty evidence, respectively); however, these benefits do not appear to be clinically significant. Triple therapy may reduce the risk of all-cause mortality compared to combination LABA/LAMA inhalers (low-certainty evidence). The certainty of the evidence was downgraded most frequently for inconsistency or indirectness. Across the four included studies, there were important differences in inclusion criteria, trial medications, and duration of follow-up. Investigation of heterogeneity was limited due to the small number of included studies. We found limited data on the effects of triple therapy compared to combination LABA/LAMA inhalers in patients with mild-moderate COPD and those without a recent exacerbation history.

Epidemiology of eczema in South-Eastern Australia.

BACKGROUND/OBJECTIVES: Eczema is a common chronic debilitating skin condition in childhood. Data on the epidemiology and natural history of eczema across the life course are lacking. This analysis aimed to describe these epidemiological features in Australian children and adults. METHODS: Data collected on eczema from four Australian cohort studies were analysed: namely HealthNuts, Melbourne Atopic Cohort Study (MACS), Tasmanian Longitudinal Health Study (TAHS) and the Australian arm of the European Community Respiratory Health Survey (ECRHS). RESULTS: Among children aged under 6 years, 28.8%-35.6% have ever-had eczema, and 16.7%-26.6% had 'current eczema'. Among those aged 6-12 years, 14.6%-24.7% had 'current eczema' with 12.0%-18.5% of those at ages of 6 and 10 years classified as having moderate-to-severe eczema according to the Scoring of Atopic Dermatitis (SCORAD) index. In adults, the prevalence of 'eczema ever' ranged between 13.8% and 48.4%. The 12-month period prevalence of eczema was 15.1% at age 18, while current eczema was 8.5% at an average age of 51, and 8.8% at an average age 53 years. Eczema was more common among young boys, but this difference became non-significant for older children and early adolescents. In contrast, eczema was more common for adult women than men. CONCLUSIONS: Eczema is common both in children and adults. The proportion of severe eczema in children was substantial.

Parental preconception BMI trajectories from childhood to adolescence and asthma in the future offspring.

BACKGROUND: Recent evidence suggests that parental exposures before conception can increase the risk of asthma in offspring. OBJECTIVE: We investigated the association between parents' preconception body mass index (BMI) trajectories from childhood to adolescence and subsequent risk of asthma in their offspring. METHODS: Using group-based trajectory modeling from the Tasmanian Longitudinal Health Study, we identified BMI trajectories for index participants (parents) when aged 4 years to 15 years. Multinomial regression models adjusted for potential confounders were utilized to estimate the association between these early-life parents' BMI trajectories and asthma phenotypes in their subsequent offspring. RESULTS: The main analysis included 1822 parents and 4208 offspring. Four BMI trajectories from age 4 years to 15 years were identified as the best-fitting model: low (8.8%), normal (44.1%), above normal (40.2%), and high (7.0%). Associations were observed between father's high BMI trajectory and risk of asthma in offspring before the age of 10 years (relative risk ratio [RRR] =1.70 [95% CI = 0.98-2.93]) and also asthma ever (RRR = 1.72 [95% CI = 1.00-2.97]), especially allergic asthma ever (RRR = 2.05 [95% CI = 1.12-3.72]). These associations were not mediated by offspring birth weight. No associations were observed for maternal BMI trajectories and offspring asthma phenotypes. CONCLUSION: This cohort study over 6 decades of life and across 2 generations suggests that the high BMI trajectory in fathers, well before conception, increased the risk of asthma in their offspring.

Impact of lifetime body mass index trajectories on the incidence and persistence of adult asthma.

BACKGROUND: High body mass index (BMI) trajectories from childhood to adulthood are associated with the development of some chronic diseases, but whether such trajectories influence adult asthma has not been investigated to date. Therefore, we investigated associations between BMI trajectories from childhood to middle age (5-43 years) and incidence, persistence and relapse of asthma from ages 43 to 53 years. METHODS: In the Tasmanian Longitudinal Health Study (n=4194), weight and height were recorded at eight time-points between 5 and 43 years of age. BMI trajectories were developed using group-based trajectory modelling. Associations between BMI trajectories and asthma incidence, persistence and relapse from age 43 to 53 years, bronchial hyperresponsiveness (BHR) at age 50 years, and bronchodilator responsiveness at age 53 years were modelled using multiple logistic and linear regression. RESULTS: Five distinct BMI trajectories were identified: average, low, child high-decreasing, child average-increasing and high. Compared with the average trajectory, child average-increasing and high trajectories were associated with increased risk of incident asthma (OR 2.6, 95% CI 1.1-6.6 and OR 4.4, 95% CI 1.7-11.4, respectively) and BHR in middle age (OR 2.9, 95% CI 1.1-7.5 and OR 3.5, 95% CI 1.1-11.4, respectively). No associations were observed for asthma persistence or relapse. CONCLUSIONS: Participants with child average-increasing and high BMI trajectories from childhood to middle age were at higher risk of incident adult asthma. Thus, encouraging individuals to maintain a normal BMI over the life course may help reduce the burden of adult asthma.

Biomarker signatures for progressive idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease in which circulatory biomarkers have the potential for guiding management in clinical practice. We assessed the prognostic role of serum biomarkers in three independent IPF cohorts: Australian Idiopathic Pulmonary Fibrosis Registry (AIPFR), Trent Lung Fibrosis (TLF) and Prospective Observation of Fibrosis in the Lung Clinical Endpoints (PROFILE). METHODS: In the AIPFR cohort, candidate proteins were assessed by ELISA as well as in an unbiased proteomic approach. LASSO (least absolute shrinkage and selection operator) regression was used to restrict the selection of markers that best accounted for the progressor phenotype at 1 year in the AIPFR cohort, and subsequently prospectively selected for replication in the validation TLF cohort and assessed retrospectively in the PROFILE cohort. Four significantly replicating biomarkers were aggregated into a progression index model based on tertiles of circulating concentrations. RESULTS: 189 participants were included in the AIPFR cohort, 205 participants from the TLF cohort and 122 participants from the PROFILE cohort. Differential biomarker expression was observed by ELISA and replicated for osteopontin, matrix metallopeptidase-7, intercellular adhesion molecule-1 and periostin for those with a progressor phenotype at 1 year. Proteomic data did not replicate. The progression index in the AIPFR, TLF and PROFILE cohorts predicted risk of progression, mortality and progression-free survival. A statistical model incorporating the progression index demonstrated the capacity to distinguish disease progression at 12 months, which was increased beyond the clinical GAP (gender, age and physiology) score model alone in all cohorts, and significantly so within the incidence-based TLF and PROFILE cohorts. CONCLUSION: A panel of circulatory biomarkers can provide potentially valuable clinical assistance in the prognosis of IPF patients.

Risk factors for chronic cough in adults: A systematic review and meta-analysis.

Despite the challenges of diagnosing and managing adult patients with chronic cough, a systematic synthesis of evidence on aetiological risk factor is lacking. We systematically searched PubMed and EMBASE to synthesize the current evidence for longitudinal associations between a wide range of risk factors and chronic cough in the general adult population, following the meta-analysis of observational studies in epidemiology (MOOSE) guidelines. The Newcastle-Ottawa scale was used to assess the quality of the included studies. Fixed-effect meta-analysis was conducted where appropriate. Of 26 eligible articles, 16 domains of risk factors were assessed. There was consistent evidence that asthma (pooled adjusted OR [aOR] = 3.01; 95% CI: 2.33-3.70; I2  = 0%; number of articles [N] = 3) and low education levels/socioeconomic status (SES) (pooled aOR = 1.46; 95% CI: 1.20-1.72; I2  = 0%; N = 3) were associated with an increased risk of chronic cough after adjusting for smoking and other confounders. While continuous smoking was associated with chronic cough (aOR = 1.81; 95% CI: 1.36-2.26; I2  = 57%; N = 3), there was too little evidence to draw conclusions for occupational exposures, outdoor air pollution, early-life exposures, diet, snoring and other chronic conditions, including obesity, chronic obstructive pulmonary disease, gastro-oesophageal reflux disease and chronic pain. Asthma, persistent smoking and lower education/SES were associated with an increased risk of chronic cough. Longitudinal associations between other factors frequently mentioned empirically (i.e., occupational exposures, air pollution and chronic respiratory conditions) need further investigation, ideally with objective and standardized measurement.

Incidence, prevalence and mortality of idiopathic pulmonary fibrosis in Australia.

BACKGROUND AND OBJECTIVE: Idiopathic pulmonary fibrosis (IPF) is one of the most common forms of interstitial lung diseases. While studies have been conducted in other countries to determine the epidemiological burden of IPF, there is limited information in Australia. Our study aimed to address this gap and generate the first estimates for the mortality, incidence and prevalence of IPF in Australia. METHODS: Estimates were generated by utilizing the novel Mortality Incidence Analysis Model (MIAMOD) method and software based on the illness-death model. Data inputs included population estimates and mortality data from the Australian Bureau of Statistics (ABS) for the period 1997-2015 and participant data from the Australian IPF Registry (AIPFR). Projections were estimated for a 10-year period up to 2025. RESULTS: Overall crude and age-standardized estimates for mortality were 5.9 and 6.3 per 100,000 population; incidence, 10.4 and 11.2 per 100,000 population; and prevalence, 32.6 and 35.1 per 100,000 population. Crude and age-standardized mortality, incidence and prevalence increased over the study period; however, they demonstrated a decreasing trend over the projected period. Persons older than 70 years constituted 9% of the population; however, they accounted for approximately 82%-83% of all deaths, incident and prevalent cases. All estimates were higher in males than in females. CONCLUSION: Our study provides the first estimates for incidence, prevalence and mortality of IPF in Australia. By reporting national estimates for IPF, our study addresses an information gap important for policy, planning and to help optimize the allocation of resources for the management of patients with IPF.

Quantitative computed tomography predicts outcomes in idiopathic pulmonary fibrosis.

BACKGROUND AND OBJECTIVE: Prediction of disease course in patients with progressive pulmonary fibrosis remains challenging. The purpose of this study was to assess the prognostic value of lung fibrosis extent quantified at computed tomography (CT) using data-driven texture analysis (DTA) in a large cohort of well-characterized patients with idiopathic pulmonary fibrosis (IPF) enrolled in a national registry. METHODS: This retrospective analysis included participants in the Australian IPF Registry with available CT between 2007 and 2016. CT scans were analysed using the DTA method to quantify the extent of lung fibrosis. Demographics, longitudinal pulmonary function and quantitative CT metrics were compared using descriptive statistics. Linear mixed models, and Cox analyses adjusted for age, gender, BMI, smoking history and treatment with anti-fibrotics were performed to assess the relationships between baseline DTA, pulmonary function metrics and outcomes. RESULTS: CT scans of 393 participants were analysed, 221 of which had available pulmonary function testing obtained within 90 days of CT. Linear mixed-effect modelling showed that baseline DTA score was significantly associated with annual rate of decline in forced vital capacity and diffusing capacity of carbon monoxide. In multivariable Cox proportional hazard models, greater extent of lung fibrosis was associated with poorer transplant-free survival (hazard ratio [HR] 1.20, p < 0.0001) and progression-free survival (HR 1.14, p < 0.0001). CONCLUSION: In a multi-centre observational registry of patients with IPF, the extent of fibrotic abnormality on baseline CT quantified using DTA is associated with outcomes independent of pulmonary function.

Relationship between concavity of the flow-volume loop and small airway measures in smokers with normal spirometry.

BACKGROUND: There is increasing evidence of small airway abnormalities in smokers despite normal spirometry. The concavity in the descending limb of the maximum expiratory flow curve (MEFV) is a recognised feature of obstruction and can provide information beyond FEV1, and potentially early smoking-related damage. We aimed to evaluate concavity measures compared to known small airway measurements. METHODS: Eighty smokers with normal spirometry had small airway function assessed: multiple breath nitrogen washout (MBNW) from which ventilation heterogeneity in the diffusion-dependent acinar (Sacin) and convection-dependent conductive (Scond) airways were assessed, and impulse oscillometry system (IOS) from which respiratory resistance and reactance at 5 Hz (R5 and X5) were measured. Concavity measures were calculated from the MEFV, partitioned into global and peripheral concavity. RESULTS: We found abnormal peripheral and global concavity as well as acinar ventilation heterogeneity are common in "normal" smokers. Concavity measures were not related to either MBNW or IOS measurements. CONCLUSION: Abnormalities in concavity indices and MBNW or oscillometry parameters are common in smokers despite normal spirometry. However, these measures likely reflect different mechanisms of peripheral airway dysfunction.

Targeting intercellular adhesion molecule-1 (ICAM-1) to reduce rhinovirus-induced acute exacerbations in chronic respiratory diseases.

The chronic respiratory non-communicable diseases, asthma and chronic obstructive pulmonary disease (COPD) are among the leading causes of global mortality and morbidity. Individuals suffering from these diseases are particularly susceptible to respiratory infections caused by bacterial and/or viral pathogens, which frequently result in exacerbation of symptoms, lung function decline, frequent hospital emergency visits and increased socioeconomic burden. Human rhinoviruses (HRV) remain the major viral pathogen group implicated in exacerbations of both asthma and COPD. The rhinoviral entry into the host lung epithelium is facilitated primarily by the adhesion site ("receptor") intercellular adhesion molecule-1 (ICAM-1), coincidentally expressed on the respiratory epithelium in these conditions. Multiple observations of increased airway ICAM-1 protein in asthmatics, smokers and smoking-related COPD have been recorded in the literature. However, the lack of robust therapies for COPD in particular has triggered a renewed interest in assessing receptor antagonism-based anti-viral strategies for treatment of intercurrent viral infections in those with pre-existing chronic lung diseases. Given the crucial role ICAM-1 plays in facilitating HRV adhesion and, thus, transmissibility to the host respiratory system, as well as the up-regulation of ICAM-1 by smoking, we summarize the role of HRV in smoking-induced COPD and especially highlight the role of ICAM-1 in epithelial viral adhesion and chronic lung disease progression. Further, the review also sheds light specifically on evolving precision therapeutic strategies in blocking ICAM-1 for preventing viral adhesion and exacerbations of COPD.

Exposure to household air pollution over 10†years is related to asthma and lung function decline.

INTRODUCTION: We investigated if long-term household air pollution (HAP) is associated with asthma and lung function decline in middle-aged adults, and whether these associations were modified by glutathione S-transferase (GST) gene variants, ventilation and atopy. MATERIALS AND METHODS: Prospective data on HAP (heating, cooking, mould and smoking) and asthma were collected in the Tasmanian Longitudinal Health Study (TAHS) at mean ages 43 and 53 years (n=3314). Subsamples had data on lung function (n=897) and GST gene polymorphisms (n=928). Latent class analysis was used to characterise longitudinal patterns of exposure. Regression models assessed associations and interactions. RESULTS: We identified seven longitudinal HAP profiles. Of these, three were associated with persistent asthma, greater lung function decline and % reversibility by age 53 years compared with the "Least exposed" reference profile for those who used reverse-cycle air conditioning, electric cooking and no smoking. The "All gas" (OR 2.64, 95% CI 1.22-5.70), "Wood heating/smoking" (OR 2.71, 95% CI 1.21-6.05) and "Wood heating/gas cooking" (OR 2.60, 95% CI 1.11-6.11) profiles were associated with persistent asthma, as well as greater lung function decline and % reversibility. Participants with the GSTP1 Ile/Ile genotype were at a higher risk of asthma or greater lung function decline when exposed compared with other genotypes. Exhaust fan use and opening windows frequently may reduce the adverse effects of HAP produced by combustion heating and cooking on current asthma, presumably through increasing ventilation. CONCLUSIONS: Exposures to wood heating, gas cooking and heating, and tobacco smoke over 10 years increased the risks of persistent asthma, lung function decline and % reversibility, with evidence of interaction by GST genes and ventilation.