{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,5]],"date-time":"2026-05-05T04:49:50Z","timestamp":1777956590523,"version":"3.51.4"},"reference-count":29,"publisher":"BMJ","issue":"1","license":[{"start":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T00:00:00Z","timestamp":1773273600000},"content-version":"unspecified","delay-in-days":11,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"funder":[{"name":"MOE Academic Research Fund (AcRF) Tier 1","award":["22-4920-A0001-0"],"award-info":[{"award-number":["22-4920-A0001-0"]}]},{"DOI":"10.13039\/501100001381","name":"National Research Foundation Singapore","doi-asserted-by":"publisher","award":["Open Fund-Large Collaborative Grant (MOH-001636)"],"award-info":[{"award-number":["Open Fund-Large Collaborative Grant (MOH-001636)"]}],"id":[{"id":"10.13039\/501100001381","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open Resp Res"],"accepted":{"date-parts":[[2026,2,16]]},"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>Chronic obstructive pulmonary disease (COPD) imposes substantial clinical and economic burdens. Early detection can allow for monitoring and timely treatment to slow its progression. Tracking of patient trajectories prior to their diagnosis can inform the timing and targeting of interventions. We aimed to identify pre-diagnosis healthcare utilisation patterns in a COPD cohort and profile the associated subgroups.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We conducted a retrospective cohort study of patients with a new inpatient or specialist outpatient clinic (SOC) diagnosis of COPD from 2018 to 2019 in a regional health system in Singapore. Their healthcare utilisation, expenditure and diagnoses from the 3\u2009years prior to diagnosis were extracted. Patients were classified into subgroups with different expenditure and utilisation patterns using Bayesian mixture modelling and compared against a propensity score\u2013matched non-respiratory control group.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>1171 patients with COPD were matched to a control and classified as either chronic (n=688) or transient healthcare users (n=483) prior to a first COPD diagnosis. Chronic users had increasing utilisation over time across all settings, recording multiple SOC visits (median, 25th\u201375th percentile: 10, 5\u201320). Transient users had low utilisation throughout, reporting fewer SOC visits than controls (transient: 0, 0\u20131, control: 2, 0\u20139). The prevalence of hypertension or hyperlipidaemia was &gt;50% in chronic users, &gt;30% in controls and &lt;30% in transient users.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Early detection strategies should focus on case-finding among patients with known risk factors in SOCs for referral to respiratory care and outreach to socially disadvantaged communities to facilitate timely access to healthcare.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjresp-2025-003686","type":"journal-article","created":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T14:55:14Z","timestamp":1773327314000},"page":"e003686","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Two distinct healthcare utilisation trajectories prior to a COPD diagnosis in a multi-ethnic Asian population: a comparison of transient and chronic users"],"prefix":"10.1136","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5046-2666","authenticated-orcid":false,"given":"Sheryl Hui-Xian","family":"Ng","sequence":"first","affiliation":[{"name":"Saw Swee Hock School of Public Health, National University of Singapore, Singapore"},{"name":"Health Services and Outcomes Research, NHG Health, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pei Yee","family":"Tiew","sequence":"additional","affiliation":[{"name":"Department of Respiratory and Critical Care Medicine, Singapore General Hospital, Singapore"},{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0417-7607","authenticated-orcid":false,"given":"Sanjay Haresh","family":"Chotirmall","sequence":"additional","affiliation":[{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore"},{"name":"Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8201-7145","authenticated-orcid":false,"given":"Wenjia","family":"Chen","sequence":"additional","affiliation":[{"name":"Saw Swee Hock School of Public Health, National University of Singapore, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John","family":"Abisheganaden","sequence":"additional","affiliation":[{"name":"Health Services and Outcomes Research, NHG Health, Singapore"},{"name":"Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore"},{"name":"Department of Respiratory and Critical Care Medicine, Tan Tock Seng Hospital, 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