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Background: Cough is a common yet heterogeneous condition. Little is known about the characteristics and course of cough in general populations. We aimed to investigate cough subclasses, their characteristics from childhood across six decades of life, and potential treatable traits in a community-based cohort., Methods: For our analysis of the Tasmanian Longitudinal Health Study (TAHS), a prospective, community-based cohort study that began on Feb 23, 1968, and has so far followed up participants in Tasmania, Australia, at intervals of 10 years from a mean age of 7 years to a mean age of 53 years, we used data collected as part of the TAHS to distinguish cough subclasses among current coughers at age 53 years. For this analysis, participants who answered Yes to at least one cough-related question via self-report questionnaire were defined as current coughers and included in a latent class analysis of cough symptoms; participants who answered No to all nine cough-related questions were defined as non-coughers and excluded from this analysis. Two groups of longitudinal features were assessed from age 7 years to age 53 years: previously established longitudinal trajectories of FEV 1 , forced vital capacity [FVC], FEV 1 /FVC ratio, asthma, and allergies-identified via group-based trajectory analysis or latent class analysis-and symptoms at different timepoints, including asthma, current productive cough, ever chronic productive cough, current smoking, and second-hand smoking., Findings: Of 8583 participants included at baseline in the TAHS, 6128 (71·4%) were traced and invited to participate in a follow-up between Sept 3, 2012, and Nov 8, 2016; 3609 (58·9%) of these 6128 returned the cough questionnaire. The mean age of participants in this analysis was 53 years (SD 1·0). 2213 (61·3%) of 3609 participants were defined as current coughers and 1396 (38·7%) were categorised as non-coughers and excluded from the latent class analysis. 1148 (51·9%) of 2213 participants in this analysis were female and 1065 (48·1%) were male. Six distinct cough subclasses were identified: 206 (9·3%) of 2213 participants had minimal cough, 1189 (53·7%) had cough with colds only, 305 (13·8%) had cough with allergies, 213 (9·6%) had intermittent productive cough, 147 (6·6%) had chronic dry cough, and 153 (6·9%) had chronic productive cough. Compared with people with minimal cough, and in contrast to other cough subclasses, people in the chronic productive cough and intermittent productive cough subclasses had worse lung function trajectories (FEV 1 persistent low trajectory 2·9%, 6·4%, and 16·1%; p=0·0011, p<0·0001; FEV 1 /FVC early low-rapid decline trajectory 2·9%, 12·1%, and 13·0%; p=0·012, p=0·0007) and a higher prevalence of cough (age 53 years 0·0%, 32·4% [26·1-38·7], and 50·3% [42·5-58·2]) and asthma (age 53 years 6·3% [3·7-10·6], 26·9% [21·3-33·3], and 41·7% [24·1-49·7]) from age 7 years to age 53 years., Interpretation: We identified potential treatable traits for six cough subclasses (eg, asthma, allergies, and active and passive smoking for productive cough). The required management of productive cough in primary care (eg, routine spirometry) might differ from that of dry cough if our findings are supported by other studies. Future population-based studies could apply our framework to address the heterogeneity and complexity of cough in the community., Funding: The National Health and Medical Research Council of Australia, The University of Melbourne, Clifford Craig Medical Research Trust of Tasmania, Victorian Asthma Foundation, Queensland Asthma Foundation, Tasmanian Asthma Foundation, The Royal Hobart Hospital Research Foundation, the Helen MacPherson Smith Trust, GlaxoSmithKline, and the China Scholarship Council., Competing Interests: Declaration of interests SCD, CJL, AJL, DSB, MJA, and JLP have investigator-initiated grants from GlaxoSmithKline. SCD, AJL, and MJA have investigator-initiated grants from Sanofi. SCD, JLP, CJL, DSB, and ABC are supported by the National Health and Medical Research Council of Australia (NHMRC). JLP is financially supported by the Australian Asthma Foundation, Craig Clifford Medical Trust, Helen McPherson Trust, and GlaxoSmithKline. AJL has received non-financial, technical support from Primus Pharmaceuticals. ABC has investigator-initiated grants from the NHMRC and the Australian Medical Research Future Fund; is a member of a data safety monitoring committee for GlaxoSmithKline, AstraZeneca, and Moderna; and was on the NHMRC Health Impact Committee, NHMRC Women in Science, and the European Respiratory Society Guideline Committee. JLP and SCD have an investigator-initiated grant from AstraZeneca. MJA has investigator-initiated grants from Pfizer and Boehringer-Ingelheim, was a consultant for Sanofi, received a speaker's fee from GlaxoSmithKline, and is an honorary member of the independent data monitoring committee for the NHMRC-funded Vietnam COPD Asthma and Prevention of Smoking 4 Trial via the Woolcock Institute. JZ is supported by The University of Melbourne and the China Scholarship Council joint PhD scholarship. All other authors declare no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Interest in lifetime lung function trajectories has increased in the context of emerging evidence that chronic obstructive pulmonary disease (COPD) can arise from multiple disadvantaged lung function pathways, including those that stem from poor lung function in childhood. To our knowledge, no previous study has investigated both obstructive and restrictive lifetime patterns concurrently, while accounting for potential overlaps between them. We aimed to investigate lifetime trajectories of the FEV 1 /forced vital capacity (FVC) ratio, FVC, and their combinations, relate these combined trajectory groups to static lung volume and gas transfer measurements, and investigate both risk factors for and consequences of these combined trajectory groups., Methods: Using z scores from spirometry measured at ages 7, 13, 18, 45, 50, and 53 years in the Tasmanian Longitudinal Health Study (n=2422), we identified six FEV 1 /FVC ratio trajectories and five FVC trajectories via group-based trajectory modelling. Based on whether trajectories of the FEV 1 /FVC ratio and FVC were low (ie, low from childhood or adulthood) or normal, four patterns of lifetime spirometry obstruction or restriction were identified and compared against static lung volumes and gas transfer. Childhood and adulthood characteristics and morbidities of these patterns were investigated., Findings: The prevalence of the four lifetime spirometry patterns was as follows: low FEV 1 /FVC ratio only, labelled as obstructive-only, 25·8%; low FVC only, labelled as restrictive-only, 10·5%; both low FEV 1 /FVC ratio and low FVC, labelled as mixed, 3·5%; and neither low FEV 1 /FVC ratio nor low FVC, labelled as reference, 60·2%. The prevalence of COPD at age 53 years was highest in the mixed pattern (31 [37%] of 84 individuals) followed by the obstructive-only pattern (135 [22%] of 626 individuals). Individuals with the mixed pattern also had the highest prevalence of parental asthma, childhood respiratory illnesses, adult asthma, and depression. Individuals with the restrictive-only pattern had lower total lung capacity and residual volume, and had the highest prevalence of childhood underweight, adult obesity, diabetes, cardiovascular conditions, hypertension, and obstructive sleep apnoea., Interpretation: To our knowledge, this is the first study to characterise lifetime phenotypes of obstruction and restriction simultaneously using objective data-driven techniques and unique life course spirometry measures of FEV 1 /FVC ratio and FVC from childhood to middle age. Mixed and obstructive-only patterns indicate those who might benefit from early COPD interventions. Those with the restrictive-only pattern had evidence of true lung restriction and were at increased risk of multimorbidity by middle age., Funding: National Health and Medical Research Council of Australia, The University of Melbourne, Clifford Craig Medical Research Trust of Tasmania, The Victorian, Queensland & Tasmanian Asthma Foundations, The Royal Hobart Hospital, Helen MacPherson Smith Trust, and GlaxoSmithKline., Competing Interests: Declaration of interests CJL, EHW, AJL, DSB, MJA, JLP, and SCD hold an investigator-initiated grant from GlaxoSmithKline for unrelated research. SCD holds an investigator-initiated grant from AstraZeneca for unrelated research. MJA holds investigator-initiated grants from Pfizer, Boehringer Ingelheim, and Sanofi for unrelated research; has undertaken an unrelated consultancy for and received assistance with conference attendance from Sanofi; and received speaker's fees from GlaxoSmithKline. AJL has received non-financial support from Primus Pharmaceuticals for unrelated research. All other authors declare no competing interests., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Prematurity has been linked to reduced lung function up to age 33 years, but its long-term effects on lung function and chronic obstructive pulmonary disease (COPD) are unknown. To address this question, we investigated associations between prematurity, lung function, and COPD in the sixth decade of life using data from the Tasmanian Longitudinal Health Study (TAHS)., Methods: Data were analysed from 1445 participants in the TAHS. Lung function was measured at 53 years of age. Gestational ages were very preterm (28 weeks to <32 weeks), moderate preterm (32 weeks to <34 weeks), late preterm (34 weeks to <37 weeks) and term (≥37 weeks). Linear and logistic regression models were fitted to investigate associations of prematurity with lung function measures (FEV 1 , forced vital capacity [FVC], FEV 1 /FVC ratio, forced expiratory flow at 25-75% of FVC [FEF 25-75% ], diffusing capacity for carbon monoxide [DLCO]) and COPD (post-bronchodilator FEV 1 /FVC less than the lower limit of normal), adjusting for sex, age, height, parental smoking during pregnancy, number of older siblings, maternal age at birth, and childhood socioeconomic status. Interactions with smoking and asthma were also investigated., Results: Of 3565 individuals with available data on gestational age from the TAHS cohort, 1445 (41%) participants were included in this study, 740 (51%) of whom were female. Compared with term birth, very to moderate preterm birth was significantly associated with an increased risk of COPD at age 53 years (odds ratio 2·9 [95% CI 1·1-7·7]). Very-to-moderate preterm birth was also associated with lower post-bronchodilator FEV 1 /FVC ratio (beta-coefficient -2·9% [95% CI -4·9 to -0·81]), FEV 1 (-190 mL [-339 to -40]), DLCO (-0·55 mmol/min/kPa [-0·97 to -0·13]), and FEF 25-75% (-339 mL/s [-664 to -14]). The association between very-to-moderate preterm birth and FEV 1 /FVC ratio was only significant among smokers (p interaction =0·0082). Similar findings were observed for moderate preterm birth when analysed as a separate group. Compared with term birth, late preterm birth was not associated with lower FEV 1 /FVC ratio or COPD., Interpretation: This is the first study to investigate the effect of prematurity on lung function into middle-age. Data show that very-to-moderate prematurity is associated with obstructive lung function deficits including COPD well into the sixth decade of life and that this effect is compounded by personal smoking., Funding: National Health and Medical Research Council (NHMRC) of Australia, European Union's Horizon 2020, The University of Melbourne, Clifford Craig Medical Research Trust of Tasmania, The Victorian, Queensland & Tasmanian Asthma Foundations, The Royal Hobart Hospital, Helen MacPherson Smith Trust, and GlaxoSmithKline., Competing Interests: Declaration of interests DSB, JLP, MJA, EHW, AJL, CJL, and SCD hold an investigator-initiated grant from GlaxoSmithKline for unrelated research. SCD holds an investigator-initiated grant from AstraZeneca for unrelated research. MJA holds investigator-initiated grants from Pfizer, Boehringer-Ingelheim, and Sanofi for unrelated research; has undertaken an unrelated consultancy for and received assistance with conference attendance from Sanofi; and received a speaker's fee from GlaxoSmithKline. BRT has received unrelated speaker and consultancy fees from Chiesi, Mundipharma, and 4D medical. AJL has received non-financial support from Primus Pharmaceuticals for unrelated research. All other authors declare no competing interests., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Longitudinal trajectories of asthma and allergies from childhood to adulthood might be differentially associated with lung function and chronic obstructive pulmonary disease (COPD), but associations with extrapulmonary comorbidities have not been well investigated. We aimed to assess these trajectories and examine their associations with lung function outcomes and profiles of comorbidities., Methods: In this prospective cohort study, data for asthma and related allergic conditions (ie, eczema, hay fever, and food allergy) were prospectively collected from the Tasmanian Longitudinal Health Study for participants aged 7-53 years originally recruited in Tasmania, Australia. All surviving individuals in the database with contact details were invited in the most recent follow-up (mean age 53 years). There were no exclusion criteria. With use of latent class analysis, we identified longitudinal trajectories of asthma and allergic conditions from 7-53 years, and profiles of self-reported extrapulmonary conditions recorded at 53 years. The associations between asthma and allergy trajectories and morbidity profiles and lung function at 53 years were investigated with regression models., Findings: Between Sept 3, 2012, and Nov 8, 2016, of 6128 individuals invited, 3609 (58·9%) individuals were enrolled. We identified five asthma and allergy trajectories: minimal and least asthma and allergies (n= 1767 [49·0%]); late-onset hay fever, no asthma (n=1065 [29·5%]); early-onset remitted asthma and allergies (n=236 [6·5%]); late-onset asthma and allergies (n=317 [8·8%]); and early-onset persistent asthma and allergies (n=224 [6·2%]); and four profiles of extrapulmonary morbidities: minimal or least disease (n=2206 [61·1%]); dominant mental health disorders (n=861 [23·9%]); dominant cardiovascular diseases or risks (n=424 [11·7%]); and multiple disorders (n=117 [3·2%]). The late-onset asthma and allergies trajectory was predominantly associated with the multiple disorders profile (relative risk ratio 3·3 [95% CI 1·9-5·9]), whereas the other asthma and allergy trajectories were associated only with the dominant mental health disorders profile. Both spirometrically defined and clinical COPD were most strongly associated with the early-onset persistent asthma and allergies trajectory (odds ratio [OR] 5·3 [95% CI 3·2-8·6]) and also with the late-onset asthma and allergies trajectory (OR 3·8 [2·4-6·1])., Interpretation: Distinct longitudinal trajectories of asthma and allergic disease from childhood to 53 years are associated with different profiles of extrapulmonary comorbidities and varying risk of COPD. These findings can inform a personalised approach in clinical guidelines and management focusing on treatable traits. Comorbidity profiles are a new target for early identification and intervention., Funding: National Health and Medical Research Council of Australia, EU's Horizon 2020, The University of Melbourne, Clifford Craig Medical Research Trust of Tasmania, The Victorian, Queensland & Tasmanian Asthma Foundations, The Royal Hobart Hospital, Helen MacPherson Smith Trust, and GlaxoSmithKline., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Lifetime lung function is related to quality of life and longevity. Over the lifespan, individuals follow different lung function trajectories. Identification of these trajectories, their determinants, and outcomes is important, but no study has done this beyond the fourth decade., Methods: We used six waves of the Tasmanian Longitudinal Health Study (TAHS) to model lung function trajectories measured at 7, 13, 18, 45, 50, and 53 years. We analysed pre-bronchodilator FEV 1 z-scores at the six timepoints using group-based trajectory modelling to identify distinct subgroups of individuals whose measurements followed a similar pattern over time. We related the trajectories identified to childhood factors and risk of chronic obstructive pulmonary disease (COPD) using logistic regression, and estimated population-attributable fractions of COPD., Findings: Of the 8583 participants in the original cohort, 2438 had at least two waves of lung function data at age 7 years and 53 years and comprised the study population. We identified six trajectories: early below average, accelerated decline (97 [4%] participants); persistently low (136 [6%] participants); early low, accelerated growth, normal decline (196 [8%] participants); persistently high (293 [12%] participants); below average (772 [32%] participants); and average (944 [39%] participants). The three trajectories early below average, accelerated decline; persistently low; and below average had increased risk of COPD at age 53 years compared with the average group (early below average, accelerated decline: odds ratio 35·0, 95% CI 19·5-64·0; persistently low: 9·5, 4·5-20·6; and below average: 3·7, 1·9-6·9). Early-life predictors of the three trajectories included childhood asthma, bronchitis, pneumonia, allergic rhinitis, eczema, parental asthma, and maternal smoking. Personal smoking and active adult asthma increased the impact of maternal smoking and childhood asthma, respectively, on the early below average, accelerated decline trajectory., Interpretation: We identified six potential FEV 1 trajectories, two of which were novel. Three trajectories contributed 75% of COPD burden and were associated with modifiable early-life exposures whose impact was aggravated by adult factors. We postulate that reducing maternal smoking, encouraging immunisation, and avoiding personal smoking, especially in those with smoking parents or low childhood lung function, might minimise COPD risk. Clinicians and patients with asthma should be made aware of the potential long-term implications of non-optimal asthma control for lung function trajectory throughout life, and the role and benefit of optimal asthma control on improving lung function should be investigated in future intervention trials., Funding: National Health and Medical Research Council of Australia; European Union's Horizon 2020; The University of Melbourne; Clifford Craig Medical Research Trust of Tasmania; The Victorian, Queensland & Tasmanian Asthma Foundations; The Royal Hobart Hospital; Helen MacPherson Smith Trust; and GlaxoSmithKline., (Copyright © 2018 Elsevier Ltd. All rights reserved.)