Abstract
Background: Life-course lung function trajectories leading to airflow obstruction, as measured by impaired FEV1/FVC (forced vital capacity), precede the onset of chronic obstructive pulmonary disease (COPD). We aimed to investigate whether individuals on impaired FEV1/FVC trajectories have an increased burden of respiratory symptoms, including those who do not meet the spirometric criteria for COPD. Methods: We analysed serial life-course data from two population-based cohort studies separately, which included respiratory symptoms and spirometry: the Tasmanian Longitudinal Health Study (TAHS, Australia) cohort was recruited at age 6–7 years and followed up until middle age (mean age 53 years; range 51–55); and the Coronary Artery Risk Development in Young Adults (CARDIA, USA) cohort was recruited at a mean age of 25 years (range 18–30) and followed up to a mean age of 55 years (range 47–64). Participants' symptom profiles at ages 53 and 55 years were derived by latent class analysis. Symptom profiles were compared across pre-bronchodilator FEV1/FVC trajectories derived by group-based modelling, then restricted to those without COPD defined by post-bronchodilator airflow obstruction (FEV1/FVC <5th percentile) at ages 51–55 years and 47–64 years. Findings: Six FEV1/FVC trajectories previously derived for TAHS were replicated in CARDIA. Optimal models identified five symptom profiles in TAHS (n=2421) and six in CARDIA (n=3153). For both cohorts, the most impaired FEV1/FVC trajectory (early low, rapid decline in TAHS; low peak, rapid decline in CARDIA) was associated with predominant wheeze (multinomial odds ratio [mOR] 6·71 [95% CI 4·10–10·90] in TAHS and 9·90 [4·52–21·70] in CARDIA) and nearly all respiratory symptoms (4·95 [2·52–9·74] and 14·80 [5·97–36·60]) at age 51–55 years in TAHS and age 47–64 years in CARDIA, compared with the average trajectory. Among individuals belonging to the three most impaired trajectories, the associations with predominant wheeze increased with worsening FEV1/FVC impairment and persisted when considering only those without spirometry-defined COPD. Additionally, for those belonging to the two rapid decline trajectories, both wheezing and usual phlegm or bronchitis were reported by 54 (20%) of 265 participants younger than 14 years in TAHS and by 31 (25%) of 123 participants aged 30 years or younger in CARDIA. Interpretation: In two independent cohorts that collected similar data, people on impaired FEV1/FVC trajectories often had a longstanding history of both wheeze and phlegm or bronchitis, and wheeze was the predominant symptom in individuals aged 47–64 years among those who had not already progressed to COPD. Funding: National Health and Medical Research Council (Australia); The University of Melbourne; Clifford Craig Medical Research Trust; Victorian, Queensland & Tasmanian Asthma Foundations; Royal Hobart Hospital Research Foundation; Helen MacPherson Smith Trust; GlaxoSmithKline; National Heart, Lung, and Blood Institute of the US National Institutes of Health.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 130-140 |
| Number of pages | 11 |
| Journal | The Lancet Respiratory Medicine |
| Volume | 13 |
| Issue number | 2 |
| DOIs | |
| State | Published - Feb 2025 |
Funding
CARDIA is conducted and supported by the US National Heart, Lung, and Blood Institute (NHLBI) in collaboration with the University of Alabama at Birmingham (grants 75N92023D00002 and 75N92023D00005), Northwestern University (grant 75N92023D00004), University of Minnesota (grant 75N92023D00006), Kaiser Foundation Research Institute (grant 75N92023D00003), and Johns Hopkins University School of Medicine (grant HHSN268200900041C). CARDIA is also partially supported by the Intramural Research Program of the National Institute on Aging and an intra-agency agreement between the US National Institute on Aging and NHLBI (grant AG0005). Additional funding has been provided by the US National Institutes of Health (NIH)-NHLBI grant R01 HL122477 (CARDIA Lung Study). This manuscript has been reviewed by CARDIA for scientific content. TAHS was supported by the National Health and Medical Research Council (NHMRC) of Australia (NHMRC project grant schemes 299901 and 1021275) and an NHMRC European collaborative grant scheme (1101313) as part of Ageing Lungs in European Cohorts funded by the EU Horizon 2020 research and innovation programme under grant agreement 633212. TAHS was also supported by The University of Melbourne; Clifford Craig Medical Research Trust; Victorian, Queensland & Tasmanian Asthma Foundations; Royal Hobart Hospital Research Foundation; Helen MacPherson Smith Trust; and GlaxoSmithKline. The TAHS-affiliated authors thank the TAHS participants and the TAHS investigators who were not co-authors of this manuscript for their assistance with obtaining funds and data collection. They thank the respiratory scientists who collected data in the lung function laboratories of Tasmania, Victoria, Queensland, and New South Wales; the research interviewers, data entry operators, and research officers; and the Archives Office of Tasmania for providing data from the 1968 and 1974 TAHS questionnaires and copies of the school medical records. The co-authors acknowledge members of the AUSCULTATE collaboration (Australia-US Collaboration to Understand Lung disease Trajectories And Timely Endpoints) who were not co-authors of this manuscript. Finally, the co-authors also thank the data manager from the University of Alabama at Birmingham for their assistance in providing the data from CARDIA.
ASJC Scopus subject areas
- Pulmonary and Respiratory Medicine