Infant body mass index trajectories and asthma and lung function.

BACKGROUND: The impact of early rapid increase in body mass index (BMI) on asthma risk and subsequent lung function remains contentious, with limited prospective studies during a critical window for lung growth. OBJECTIVE: Our aim was to investigate the associations between BMI trajectories in the first 2 years of life and adolescent asthma and lung function. METHODS: Anthropometric data on 620 infants from the Melbourne Atopy Cohort Study were collected up to 18 times in the first 24 months of the study. BMI trajectories were developed by using group-based trajectory modeling. Associations between these trajectories and spirometry, fractional exhaled nitric oxide level, and current asthma status at 12 and/or 18 years of age were modeled by using multiple linear and logistic regression. RESULTS: A total of 5 BMI trajectories were identified. Compared with those children with the "average" trajectory, the children belonging to the "early-low and catch-up" and "persistently high" BMI trajectories were at higher risk of asthma at the age of 18 years (odds ratios = 2.2 [95% CI = 1.0-4.8] and 2.4 [95% CI = 1.1-5.3], respectively). These trajectories were also associated with a lower ratio of FEV1 to forced vital capacity and a higher fractional exhaled nitric oxide levels at age 18 years. In addition, children belonging to the persistently low trajectory had lower FEV1 (ß = -183.9 mL [95% CI = -340.9 to -26.9]) and forced vital capacity (ß = -207.8 mL [95% CI = -393.6 to -22.0]) values at the age of 18 years. CONCLUSION: In this cohort, the early-low and catch-up and persistently high trajectories were associated with asthma and obstructive lung function pattern in adolescence. Having a persistently low BMI at an early age was associated with a restrictive pattern. Thus, maintenance of normal growth patterns may lead to improved adolescent respiratory health.

Transient childhood wheeze is associated with less atopy in adolescence.

BACKGROUND: The relationships between childhood wheeze phenotypes and subsequent allergic conditions other than asthma, including hay fever, eczema and sensitization, have not been widely reported. We aimed to investigate this relationship up to late adolescence. METHODS: Using five childhood wheeze phenotypes defined from 620 children in a high-atopy risk birth cohort (Melbourne Atopy Cohort Study), we investigated their relationships with sensitization, eczema, hay fever and fractional exhaled nitric oxide (FeNO) at ages 12 and/or 18 years using logistic and linear regression models. RESULTS: 'Early Persistent wheeze' was associated with the increased risk of eczema (odds ratio: 3.69; 95% CI: 1.23, 11.12) and sensitization (4.52; 1.50, 13.64) at 12 years. 'Intermediate Onset wheeze' was associated with the increased risk of eczema at 12 years (2.57; 1.11, 5.97), hay fever at 12 (2.87; 1.44, 5.74) and 18 years (2.19; 1.20, 4.02), sensitization at 12 (2.25; 1.17, 4.34) and 18 years (2.46; 1.18, 5.12), and raised FeNO at 18 years. 'Late Onset wheeze' was associated with the increased risk of hay fever at 12 (5.18; 1.11, 24.20) and 18 years (4.20; 1.03, 17.11) and sensitization at 12 years (3.27; 0.81, 13.27). In contrast, 'Early Transient wheeze' was associated with the reduced risk of eczema (0.44; 0.20, 0.96), hay fever (0.57; 0.33, 0.99) and sensitization (0.59; 0.35, 0.99) at 18 years and a lower FeNO compared with 'Never/Infrequent wheezers'. CONCLUSIONS: Persistent wheeze phenotypes were associated with allergic outcomes up to 18 years with 'Intermediate Onset wheeze' being the most atopic group. In contrast, 'Early Transient wheezers' had less risk of allergic outcomes at 18 years. This protective effect may reassure parents of wheezy infants and young children.

Longitudinal analysis of respiratory outcomes among bauxite exposed workers in Western Australia.

INTRODUCTION: Occupational exposure to bauxite is common in the aluminium industry but little is known about the associated health effects. This study investigates respiratory health in relation to respirable bauxite dust exposure longitudinally over a 13 year period. METHODS: An inception cohort study recruited 91 male bauxite miners and 363 male alumina refinery workers. Annual measurements of respiratory symptoms and lung function were made. Cumulative exposure to bauxite was derived from job histories and air monitoring data. Mixed-effects modeling was used. RESULTS: No associations were found between cumulative bauxite exposure and respiratory symptoms or lung function. However, when analysis was restricted to the first three rounds, FEV1 was significantly lower in all exposure groups than in those unexposed but with no significant trend. CONCLUSION: Increasing exposure to bauxite dust in the aluminum industry was not associated with respiratory symptoms or consistent decrements in lung function.

Early-life risk factors and incidence of rhinitis: results from the European Community Respiratory Health Study--an international population-based cohort study.

BACKGROUND: Rhinitis is an increasingly common condition with a heavy health care burden, but relatively little is known about its risk factors. OBJECTIVE: To examine the association between early-life factors and the development of rhinitis in the European Community Respiratory Health Study (ECRHS). METHODS: In 1992-1994, community-based samples of 20-44-year-old people were recruited from 48 centers in 22 countries. On average, 8.9 years later, 28 centers reinvestigated their samples. Onset of rhinitis was reported by 8486 participants in interviewer-led questionnaires. Cox regression was used to assess independent predictors of rhinitis at ages ≤5, 6-10, 11-20, and ≥21 years. RESULTS: The crude lifelong incidence of rhinitis was 7.00/1000/year (men) and 7.95/1000/year (women) (P = .002). Women developed less rhinitis in later childhood (hazard ratios [HR], 0.63; 95% CI, 0.47-0.85) and more rhinitis in adulthood (HR, 1.36; 95% CI, 1.11-1.66) than did men. In atopic subjects, siblings were associated with lower risk of rhinitis throughout life (pooled HR, 0.94; 95% CI, 0.91-0.98 per 1 sibling). Early contact with children in the family or day care was associated with less incidence of rhinitis, predominantly before age 5 years (HR, 0.84; 95% CI, 0.72-0.99). Early childhood pets or growing up on a farm was associated with less incidence of rhinitis in adolescence (HR, 0.50; 95% CI, 0.37-0.68). Combining these factors showed evidence of a dose-response relationship (trend P = .0001). CONCLUSIONS: Gender is a strong risk factor for rhinitis, with age patterns varying according to atopic status. Protective effects of early contact with children and animals were suggested for incident rhinitis, with risk patterns varying by age window and atopic status.

Effectiveness of Interventions Targeting Treatable Traits for the Management of Obstructive Airway Diseases: A Systematic Review and Meta-Analysis.

BACKGROUND: The management of obstructive airway diseases (OADs) is complex. The treatable traits (TTs) approach may be an effective strategy for managing OADs. OBJECTIVE: To determine the effectiveness of interventions targeting TTs for managing OADs. METHODS: Ovid Embase, Medline, CENTRAL, and CINAHL Plus were searched from inception to March 9, 2022. Studies of interventions targeting at least 1 TT from pulmonary, extrapulmonary, and behavioral/lifestyle domains were included. Two reviewers independently extracted relevant data and performed risk-of-bias assessments. Meta-analyses were performed using random-effects models. Subgroup and sensitivity analyses were carried out to explore heterogeneity and to determine the effects of outlying studies. RESULTS: Eleven studies that used the TTs approach for OAD management were identified. Traits targeted within each study ranged from 13 to 36. Seven controlled trials were included in meta-analyses. TT interventions were effective at improving health-related quality of life (mean difference [MD] = -6.96, 95% CI: -9.92 to -4.01), hospitalizations (odds ratio [OR] = 0.52, 95% CI: 0.39 to 0.69), all-cause-1-year mortality (OR = 0.65, 95% CI: 0.45 to 0.95), dyspnea score (MD = -0.29, 95% CI: -0.46 to -0.12), anxiety (MD = -1.61, 95% CI: -2.92 to -0.30), and depression (MD = -2.00, 95% CI: -3.53 to -0.47). CONCLUSION: Characterizing TTs and targeted interventions can improve outcomes in OADs, which offer a promising model of care for OADs.

Treatable traits in an English cohort: prevalence and predictors of future decline in lung function and quality of life in COPD.

BACKGROUND: "Treatable traits (TTs)" is a precision medicine approach for facilitating multidimensional assessment of every patient with chronic airway disease, in order to determine the core traits associated with disease outcomes where targeted treatments may be applied. OBJECTIVES: To determine the prevalence of TTs in chronic obstructive pulmonary disease (COPD) and which traits predict future decline in lung function and quality of life (QoL). METHODS: A 4-year longitudinal evaluation was conducted using data from 3726 participants in the English Longitudinal Study of Ageing (ELSA). TTs were identified based on published recommendations. Traits that predicted decline in lung function and QoL were analysed using generalised estimating equations. RESULTS: Overall, 21 TTs, including pulmonary (n=5), extra-pulmonary (n=13) and behavioural/lifestyle risk-factors (n=3) were identified. In multivariate analyses, the traits of chronic bronchitis (ß -0.186, 95% CI -0.290 to -0.082), breathlessness (ß -0.093, 95% CI -0.164 to -0.022), underweight (ß -0.216, 95% CI -0.373 to -0.058), sarcopenia (ß -0.162, 95% CI -0.262 to -0.061) and current smoking (ß -0.228, 95% CI -0.304 to -0.153) predicted decline in forced expiratory volume in 1 s (FEV1). Of the seven traits that predicted decline in QoL, depression (ß -7.19, 95% CI -8.81 to -5.57) and poor family and social support (ß -5.12, 95% CI -6.65 to -3.59) were the strongest. CONCLUSION: The core TTs of COPD associated with a decline in lung function and QoL were identified. Targeting these impactful traits with individualised treatment using a precision medicine approach may improve outcomes in people with COPD.

Outdoor air pollution as a trigger for out-of-hospital cardiac arrests.

BACKGROUND: Epidemiologic studies have reported associations between fine particulate air pollution and cardiovascular mortality or hospitalization for cardiac events. However the evidence regarding the association between air pollution and acute cardiac events, such as out-of-hospital cardiac arrest, is inconsistent. METHODS: We investigated the association between particulate matter (PM) air pollution and out-of-hospital cardiac arrest using a case-crossover study of adults (age, 35+ years) in Melbourne, Australia. We included 8434 cases identified through the Victorian Cardiac Arrest Registry from 2003 through 2006. We excluded arrests with an obvious preceding noncardiac event such as trauma, poisoning, or drowning, leaving only those events that were presumed to have cardiac etiology. Air pollution concentrations obtained from a central monitoring site were used for day of the arrest and for lag 1, lag 2, and lag 3, including the average lag 0-1. RESULTS: An interquartile range increase of 4.26 microg/m3 in PM2.5 over 2 days (lag 0-1) was associated with an increase in risk for an out-of-hospital cardiac arrest of 3.6% (95% confidence interval = 1.3% to 6.0%). PM10 and carbon monoxide also showed associations, but not as strong as for PM2.5. Longer lag periods did not show such strong relationships. There was no association of these cardiac events with ozone, sulfur dioxide, or nitrogen dioxide in any lag period. Individuals age 65-74 years old were most susceptible to PM2.5 exposure, while those 75 years and older had the lowest risk. CONCLUSION: These findings support an association between daily average PM2.5 concentrations and an increased risk of out-of-hospital cardiac arrests.

Is potroom asthma due more to sulphur dioxide than fluoride? An inception cohort study in the Australian aluminium industry.

OBJECTIVES: Although an asthma-like syndrome has been recognised in aluminium smelter workers for over 70 years, the causal agent has been difficult to identify. METHODS: An inception cohort study was conducted at two Australian aluminium smelters where 446 employees participated over a period of 9 years. Cumulative exposures between interviews were estimated from job histories using a task exposure matrix based on measurements in the smelters. Participants completed an MRC respiratory questionnaire, spirometry and methacholine challenge test. Data were analysed with generalised estimating equations to allow for repeated measurements of each participant. RESULTS: Wheeze and chest tightness, the two symptoms most closely related to asthma, showed associations with occupational exposures. SO(2) exposure was significantly associated with these symptoms, bronchial hyper-responsiveness (BHR) to methacholine (a feature of asthma), airflow limitation (reduced forced expiratory volume in 1 second/forced vital capacity ratio) and longitudinal decline in lung function. Fluoride exposure was associated with the same outcomes, but less strongly. Inhalable dust and the benzene soluble fraction (BSF) were associated with symptoms of asthma and BHR. Although many of the exposures were highly correlated, further modelling suggested that of the known respiratory irritants, SO(2) was more likely than fluoride to be primarily responsible for the symptoms observed. Fluoride, inhalable dust and SO(2) were the most important airborne contaminants associated with effects on lung function. CONCLUSIONS: The observed effects were detected at contaminant levels within occupational exposure standards, so further reductions are required, particularly in SO(2) exposures.

Breast-feeding and atopic disease: a cohort study from childhood to middle age.

BACKGROUND: The literature regarding the association between breast-feeding and atopic diseases has been contradictory. OBJECTIVE: We have assessed the relationship between breast-feeding and atopic disorders in a cohort followed into middle age. METHODS: The Tasmanian Asthma Study is a population-based prospective cohort study that has followed participants from the age of 7 to 44 years. Exclusive breast-feeding in the first 3 months of life was examined as a risk factor for atopic diseases by using multiple logistic regression and generalized estimating equation analyses. RESULTS: At age 7 years, exclusively breast-fed children with a maternal history of atopy had a marginally lesser risk of current asthma than those not exclusively breast-fed (odds ratio [OR], 0.8; 95% CI, 0.6-1.0). However, after age 7 years, the risk reversed, and exclusively breast-fed children had an increased risk of current asthma at 14 (OR, 1.46; 95% CI, 1.02-2.07), 32 (OR, 1.84; 95% CI, 1.06-3.3), and 44 (OR, 1.57; 95% CI, 1.15-2.14) years. Exclusively breast-fed children also had a reduced risk of food allergy at age 7 years but an increased risk of food allergy (OR, 1.26; 95% CI, 1.1-1.5) and allergic rhinitis (OR, 1.2; 95% CI, 1.0-1.3) at 44 years. CONCLUSION: Exclusively breast-fed babies with a maternal history of atopy were less likely to develop asthma before the age of 7 years, but more likely to develop asthma after the age of 7 years. CLINICAL IMPLICATIONS: The current recommendation to breast-feed high-risk infants for protection against early wheezing illness can be confirmed. However, the recommendation should be reconsidered for protection against allergic asthma and atopy in the longer term.