Michael J. Abramson

Background: Individuals with Preserved Ratio Impaired Spirometry (PRISm), defined as FEV1/FVC ≥0.7 and FEV1 <80% predicted, are at higher risk of developing COPD. However, data for Australian adults are limited. We aimed to describe prevalence of PRISm and its relationship with clinical characteristics in Australia. Method: Data from the Burden of Lung Disease (BOLD) Australia study of randomly selected adults aged ≥40 years from six sites was classified into airflow limitation, PRISm, or normal spirometry groups. Demographic, clinical characteristics, and lung function were compared between groups. Results: Of the study sample (n = 3518), 387 (11%) had PRISm, 549 (15.6%) had airflow limitation, and 2582 (73.4%) had normal spirometry. PRISm was more common in Indigenous Australian adults. Adults with PRISm had more frequent respiratory symptoms, more comorbidities, greater health burden and poorer quality of life than those with normal spirometry. Pre- and post-bronchodilator FEV1 and FVC were lower in adults with PRISm than those with airflow limitation. Adults with PRISm were less likely to use respiratory medicine than those with airflow limitation (OR = 0.56, 95% CI 0.38-0.81). Conclusions: PRISm was present in 11% of adults in this study and they had similar respiratory symptoms and health burden as adults with airflow limitation.

Purpose: Pulmonary rehabilitation (PR) is highly effective but underutilised. Pathways to home-based PR (HBPR) from general practice could improve utilisation, but program fidelity in this setting is unknown. This study aimed to explore the fidelity of HBPR in people referred from general practice. Methods: Secondary analysis of intervention-group data from two-arm cluster RCT (RADICALS-interdisciplinary intervention for people with COPD including smoking cessation support, home medicine reviews and 8-weeks HBPR). HBPR fidelity assessed by the extent to which exercise training was prescribed according to protocol. Completion of HBPR and contributing factors were determined. Results: 107 participants (68% of intervention group) were referred to HBPR, with n = 75 (70%) commencing the program (mean age 68 years, FEV1 65% predicted, median mMRC 1). Aerobic training was prescribed according to protocol for 74% of participants in week one, and on average 89% of participants in weeks 2-8. Resistance training was prescribed according to protocol for 98% and 88% of participants (Week 1 and Weeks 2-8, respectively). Rehabilitation completers (n = 57, 76%) were 26 times more likely to have attended the Week 2 phone call (95% CI 2-352). Clinically meaningful improvements were achieved in health-related quality of life (SGRQ) and health status (CAT) following rehabilitation. Conclusion: PR program fidelity can be maintained when delivering HBPR to people with COPD referred directly from general practice. Early engagement with PR may be key to supporting rehabilitation completion.

Objective: The impact of household air pollution (HAP) on obstructive sleep apnoea (OSA) was unclear from the literature. We aimed to investigate the associations between HAP exposure over 10 years and OSA in middle-aged adults. Methods: Using the Tasmanian Longitudinal Health Study (TAHS), seven longitudinal HAP profiles were previously identified using information on household heating, cooking, mould, active and passive smoking exposure collected at two ages spanning 10 years (at mean ages 43 and 53 years). Probable OSA was only measured at 53 years using validated STOP-Bang, Berlin and OSA-50 questionnaires. Medically diagnosed OSA was self-reported. Multivariable logistic regression was used to assess the associations between HAP profiles and each definition of OSA, adjusting for age, sex, socioeconomic status and ambient air pollution. Results: Compared with the "Least exposed" profile, characterised by reverse-cycle air conditioning, electric cooking and no smoking exposure, the "Wood and gas heating/gas cooking/smoking" profile was associated with both probable OSA defined using OSA-50 (aOR=2.39, 95%CI 1.61-3.53) and medically diagnosed OSA (aOR=2.31, 1.06-5.05). The "All gas" and "Wood heating/smoking" profiles were associated with OSA-50-defined probable OSA (aOR=1.35, 1.01-1.79; aOR=1.47, 1.10-1.96 respectively). Additionally, the "All gas" profile was associated with incident medically diagnosed OSA (aOR=2.15, 1.06-4.38). Conclusions: Sustained exposure to wood and gas heating and gas cooking especially when combined with tobacco smoke increased the risk of OSA over 10 years in middle age. Our study strengthens the rationale for including the potential adverse effects of HAP on mid-life OSA within public educational programs and guidelines.

Rising heat stress due to climate warming poses a significant threat to human health, and greenness offers a nature-based solution to mitigate heat-related health impacts and enhance resilience. Although global greenness has increased, it remains unclear whether these trends align with the population's heat mitigation needs. In this study, we integrated spatially resolved demographic data with satellite-derived greenness metric and reanalysis-based heat stress data to construct a global profile of joint exposure at 1 × 1 km resolution from 2000 to 2022. We found that 69.3% of global populated areas and 41.3% of the global population (∼2.9 billion people) were exposed to increasing heat stress but decreasing greenness (IHDG), representing the most concerning situation for heat mitigation. Urban populations were disproportionately affected, with 50.8% exposed compared to 27.1% in rural areas. Low- and middle-income countries exhibited more pronounced trends of increasing heat stress and bore the greatest burden from IHDG, accounting for 85% of total exposed populations. Moreover, there was a notable demographic shift in IHDG-exposed populations toward older groups, exacerbating the heat mitigation crisis. This study advances the understanding of the joint dynamics of heat stress and greenness and provides a profile of population exposure at a fine grid level. By highlighting the scale of IHDG conditions, our findings emphasize the urgent need to address this environmental challenge and a significant opportunity for improving greenness to mitigate increasing heat globally. The spatially detailed assessment maps offer essential data for informed decision-making.

Background: While short-term occupational exposures to many agents are associated with increased risk of asthma, the long-term consequences of exposure have not been well understood. We investigated the effects of occupational exposures over two decades on the incidence of asthma. Methods: This population-based, multicentre cohort was assessed at baseline (European Community Respiratory Health Survey (ECRHS)1) and followed up twice over 20 years (ECRHS2 and ECRHS3). This analysis included data for 5591 participants with complete work histories and free of asthma at baseline. Incident adult-onset asthma was defined as either an asthma attack, woken by an attack of shortness of breath and/or current asthma medication in the last 12 months before each timepoint, without asthma at a previous survey. An updated asthma-specific job exposure matrix was used to estimate exposures to asthmagens. Adjusted Poisson models were fitted with generalised estimating equations to estimate asthma incidence. Results: Ever high exposure to high molecular weight sensitisers (rate ratio (RR)=1.31; 95% CI 1.15 to 1.63), irritants (RR=1.29; 1.09-1.54), biocides (RR=1.42; 1.12-1.79), only low exposure to low molecular weight sensitisers (RR=1.26; 1.08-1.47), mites (RR=1.48; 1.12-1.94) and reactive chemicals (RR=1.24; 1.06-1.45) were associated with increased incidence of asthma. Asthma incidence also increased with ever high or cumulative exposure to these exposures and for specific exposure to wood dust, cleaning agents and bleach. The population-attributable fraction for adult-onset asthma due to occupational exposures was 18% (16.9-19.4%). Conclusions: This strengthens the evidence that occupational exposures to sensitisers and chemical irritants contribute substantial risk and a substantive attributable fraction of adult-onset asthma. Control of implicated hazardous exposures and periodic screening of exposed workers should be considered.