{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T12:46:58Z","timestamp":1785847618591,"version":"3.56.0"},"reference-count":35,"publisher":"BMJ","issue":"8","license":[{"start":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T00:00:00Z","timestamp":1785801600000},"content-version":"unspecified","delay-in-days":3,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2026,7,22]]},"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Frailty, a critical health indicator of ageing, poses significant public health challenges for individuals and society. This study analysed the longitudinal association between changes in employment status and frailty among middle-aged and older adults in Korea across different employment types. It also examined how employment transitions impact frailty components, particularly weakness, isolation and exhaustion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>A longitudinal study.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Setting<\/jats:title>\n                    <jats:p>A nationwide community-based longitudinal study using data from the Korean Longitudinal Study of Aging from 2006 to 2022.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Participants<\/jats:title>\n                    <jats:p>Individuals aged 45 years or older residing in private households across Korea (excluding Jeju Island) enrolled in Wave 1 (2006). For consistency, only participants with at least four observations during the entire study period were retained. Those with fewer than four observations (n=48\u2009228) were excluded, amounting to a final of 6122 participants, of whom 2718 were men and 3404 were women. Furthermore, for the subgroup analysis of employment types, participants not classified as regular, temporary, daily, self-employed or unpaid family workers were excluded.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Primary and secondary outcome measures<\/jats:title>\n                    <jats:p>The primary outcome was frailty assessed using the Korean Frailty Instrument. Secondary outcomes were the individual frailty components, including weakness, isolation and exhaustion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The study included 6122 participants (2718 men and 3404\u2009women). Frailty was observed in 3.9% of men and 8.5% of women. Returning to or maintaining employment was significantly associated with reduced frailty risk between both genders (male: Unemployed \u2192 Working OR 0.61, Working \u2192 Working OR 0.59; female: Unemployed \u2192 Working OR 0.68, Working \u2192 Working OR 0.77). Employment type-based analysis revealed that transitioning to permanent employment has the strongest protective effect on men (Unemployed \u2192 Permanent Employment OR 0.25).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Returning to or maintaining employment was associated with a lower risk of frailty. Promoting stable employment environments and encouraging labour force participation among middle-aged and older adults may contribute to better health outcomes in ageing societies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2026-116676","type":"journal-article","created":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T11:56:26Z","timestamp":1785844586000},"page":"e116676","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Association between changes in working status and frailty across different types of employment: a longitudinal study in Korea, the world\u2019s most rapidly ageing nation"],"prefix":"10.1136","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0005-0207-8826","authenticated-orcid":false,"given":"Su-Min","family":"Park","sequence":"first","affiliation":[{"name":"Yonsei University Graduate School Department of Public Health, Seodaemun-gu, Korea (the Republic 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