{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T01:09:09Z","timestamp":1789088949145,"version":"build-2803163510"},"reference-count":29,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T00:00:00Z","timestamp":1789084800000},"content-version":"vor","delay-in-days":78,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Rheumatol"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Clinicians often recognise broader deterioration in a patient\u2019s overall condition that is not fully captured by conventional disease-specific measures. Ageing is associated with reduced physiological reserve and altered body fluid distribution. However, objective markers that capture these changes remain limited. Because the extracellular water-to-total body water ratio (ECW\/TBW) reflects fluid distribution, we hypothesised that its prognostic relevance is age-dependent rather than uniform.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In this retrospective cohort study, 186 adults with rheumatoid arthritis underwent bioelectrical impedance analysis in 2017 and were followed until December 2025. The primary outcome was a composite of all-cause death or transition to do-not-attempt-resuscitation\/best supportive care (DNAR\/BSC) status. Cox proportional hazards models including an age \u00d7 ECW\/TBW interaction term were used. Age-stratified analyses used the cohort median age (68 years).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      During a median follow-up of 95.2 months, 17 participants experienced death or transition to DNAR\/BSC status. Age was strongly associated with risk (HR per 10-year increase 2.53, 95% CI 1.47\u20134.34;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001). In age-adjusted models, ECW\/TBW was not independently associated with the outcome (HR per 0.01 increase 1.10, 95% CI 0.88\u20131.37;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.40). In contrast, the age \u00d7 ECW\/TBW interaction was significant (HR 1.22, 95% CI 1.05\u20131.42;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.010), suggesting that the association between ECW\/TBW and the outcome differed according to age. Elevated ECW\/TBW was associated with higher risk among older participants (HR 3.10, 95% CI 1.21\u20138.63;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.018), but not among younger individuals. In competing-risk analyses, elevated ECW\/TBW was associated with a higher cumulative incidence of non-planned admissions among older participants (Gray\u2019s test\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.014).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The prognostic relevance of ECW\/TBW appeared to vary by age, emerging primarily in later life rather than functioning as a uniform risk marker. These exploratory findings suggest that ECW\/TBW may reflect aspects of age-related physiological vulnerability and may help identify older individuals at increased risk of non-planned hospitalisations and other unstable clinical trajectories. As a simple non-invasive measure, ECW\/TBW may complement disease activity-centred assessment, although external validation is required.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s41927-026-00668-2","type":"journal-article","created":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T11:06:48Z","timestamp":1782385608000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Age modifies the prognostic relevance of extracellular water-to-total body water ratio in rheumatoid arthritis: a retrospective cohort study"],"prefix":"10.1186","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0384-8678","authenticated-orcid":false,"given":"Daisuke","family":"Kobayashi","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yoko","family":"Wada","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Masanori","family":"Sudo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eriko","family":"Hasegawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shunsuke","family":"Sakai","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayako","family":"Wakamatsu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukiko","family":"Nozawa","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroe","family":"Sato","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takeshi","family":"Kuroda","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suguru","family":"Yamamoto","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"issue":"9868","key":"668_CR1","doi-asserted-by":"publisher","first-page":"752","DOI":"10.1016\/S0140-6736(12)62167-9","volume":"381","author":"A Clegg","year":"2013","unstructured":"Clegg A, Young J, Iliffe S, Rikkert MO, Rockwood K. 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The original prospective body composition assessment was approved by the Niigata University Ethics Review Committee for Research Involving Human Subjects (approval number: 2016-0046), and the present retrospective secondary analysis was approved by the Niigata University Ethics Review Committee for Research Involving Human Subjects (approval number: 2022\u2009\u2212\u20090282). The requirement for informed consent for the present analysis was waived by the Niigata University Ethics Review Committee for Research Involving Human Subjects due to the retrospective nature of the study and the use of de-identified clinical data.","order":1,"name":"Ethics","label":"Ethics approval and consent to participate","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","order":2,"name":"Ethics","label":"Consent for publication","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"The authors declare no competing interests.","order":3,"name":"Ethics","label":"Competing interests","group":{"name":"EthicsHeading","label":"Declarations"}}],"article-number":"68"}}