{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T08:10:17Z","timestamp":1778573417459,"version":"3.51.4"},"reference-count":33,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T00:00:00Z","timestamp":1777593600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,5,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Obesity and metabolic syndrome are now common among patients with Crohn\u2019s disease, with prevalence rates approaching those of the general population. Yet the Crohn\u2019s Disease Activity Index (CDAI), which still underpins the design and interpretation of many phase 3 trials, was developed in an era dominated by undernutrition and only weakly reflects intestinal inflammation. In this Viewpoint, we revisit the construction of the CDAI and argue that its weight component is particularly ill-adapted to contemporary Crohn\u2019s disease populations. Because the index rewards weight gain and penalizes weight loss relative to an \u201cideal\u201d or pre-illness body weight, increasing body mass index can drive CDAI scores down, even when symptoms and inflammatory burden are unchanged. Using simple numerical examples, we show how obese patients with the same clinical activity as normal-weight individuals may be reclassified from moderate\u2013severe disease into apparent clinical remission due solely to the weight term. We discuss the implications of this bias for trial eligibility, endpoint assessment, and therapeutic strategies that modify body weight, and outline pragmatic options to modernize disease activity assessment in the era of obesity.<\/jats:p>","DOI":"10.1093\/ecco-jcc\/jjag050","type":"journal-article","created":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T11:29:30Z","timestamp":1775561370000},"source":"Crossref","is-referenced-by-count":0,"title":["Crohn\u2019s Disease Activity Index in the era of obesity: time to abandon it?"],"prefix":"10.1093","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8123-9213","authenticated-orcid":false,"given":"Xavier","family":"Treton","sequence":"first","affiliation":[{"name":"Paris IBD Center, Groupe Hospitalier Priv\u00e9 Ambroise Par\u00e9\u2013Hartmann , Neuilly-sur-Seine 92600,","place":["France"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carmen","family":"Stefanescu","sequence":"additional","affiliation":[{"name":"Paris IBD Center, Groupe Hospitalier Priv\u00e9 Ambroise Par\u00e9\u2013Hartmann , Neuilly-sur-Seine 92600,","place":["France"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charlotte","family":"Mailhat","sequence":"additional","affiliation":[{"name":"Paris IBD Center, Groupe Hospitalier Priv\u00e9 Ambroise Par\u00e9\u2013Hartmann , Neuilly-sur-Seine 92600,","place":["France"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoram","family":"Bouhnik","sequence":"additional","affiliation":[{"name":"Paris IBD Center, Groupe Hospitalier Priv\u00e9 Ambroise Par\u00e9\u2013Hartmann , Neuilly-sur-Seine 92600,","place":["France"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6303-8557","authenticated-orcid":false,"given":"Eric","family":"Vicaut","sequence":"additional","affiliation":[{"name":"Unit\u00e9 de Recherche Clinique Lariboisi\u00e8re\u2013Saint-Louis, Assistance Publique\u2013H\u00f4pitaux de Paris , Paris 75010,","place":["France"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2026,5,9]]},"reference":[{"key":"2026051203175942400_jjag050-B1","volume-title":"Obesity and Overweight. 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