{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T19:05:46Z","timestamp":1784574346046,"version":"3.55.0"},"reference-count":36,"publisher":"American Diabetes Association","issue":"8","license":[{"start":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T00:00:00Z","timestamp":1781136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.diabetesjournals.org\/journals\/pages\/license"}],"funder":[{"DOI":"10.13039\/100004339","name":"Sanofi","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004339","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["diabetesjournals.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2026,8,1]]},"abstract":"<jats:sec>\n                    <jats:title>OBJECTIVE<\/jats:title>\n                    <jats:p>To characterize associations of C-peptide measurements with type 1 diabetes (T1D) complications across long-term clinical follow-up in a large representative population cohort (Scottish Diabetes Research Network Type 1 Bioresource [SDRNT1BIO]).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESEARCH DESIGN AND METHODS<\/jats:title>\n                    <jats:p>SDRNT1BIO includes people with a clinical diagnosis of T1D who are aged 16 years or older at enrollment. Their median diabetes duration is 21 (interquartile range 11\u201331) years. C-peptide was measured in an untimed blood sample using the Roche immunoassay with a lower limit of detection of 3 pmol\/L. Incident events and continuous outcomes were captured through electronic health record linkage across follow-up. Associations were studied using Poisson generalized linear models and linear mixed models adjusted for sex, age, time-updated T1D duration, year of entry, and age\/T1D duration interaction.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>RESULTS<\/jats:title>\n                    <jats:p>Participants (n = 5,630) were followed for a median of 10.8 years. Inverse associations were found between baseline C-peptide level and diabetic ketoacidosis (DKA) (P &amp;lt; 0.0001; no. of events = 1,015), severe hospitalized hypoglycemia (SHH) (P = 0.0055; n = 539), and incident retinopathy (P &amp;lt; 0.0001; n = 1,172). These associations persisted when adjusted for time-updated glycosylated hemoglobin. No associations were found between baseline C-peptide levels and cardiovascular disease (P = 0.9; n = 714) or death (P = 0.8; n = 566). In a subset of participants (n = 407) with serial C-peptide measures, follow-up C-peptide level was inversely associated with risk for DKA (P &amp;lt; 0.001; n = 92) and there was a borderline association with SHH (P = 0.015; n = 28).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>CONCLUSIONS<\/jats:title>\n                    <jats:p>These data demonstrate the importance of C-peptide level and its maintenance for glycemic control and avoidance of acute and chronic complications of T1D.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2337\/dc25-1738","type":"journal-article","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T14:13:02Z","timestamp":1781187182000},"page":"1348-1356","update-policy":"https:\/\/doi.org\/10.2337\/ada-journal-policies","source":"Crossref","is-referenced-by-count":0,"title":["Long-term Effect of C-Peptide Level on Clinical Outcomes in the Scottish Type 1 Bioresource Cohort"],"prefix":"10.2337","volume":"49","author":[{"given":"Joseph C.","family":"Mellor","sequence":"first","affiliation":[{"name":"Diabetes Informatics & Epidemiology Unit, Institute of Genetics and Cancer, University of Edinburgh 1 , Edinburgh, Scotland, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luke A.K.","family":"Blackbourn","sequence":"additional","affiliation":[{"name":"Diabetes Informatics & Epidemiology Unit, Institute of Genetics and Cancer, University of Edinburgh 1 , Edinburgh, Scotland, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3292-4633","authenticated-orcid":false,"given":"Stuart J.","family":"McGurnaghan","sequence":"additional","affiliation":[{"name":"Diabetes Informatics & Epidemiology Unit, Institute of Genetics and Cancer, University of Edinburgh 1 , Edinburgh, Scotland, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5217-1034","authenticated-orcid":false,"given":"Paul M.","family":"McKeigue","sequence":"additional","affiliation":[{"name":"Diabetes Informatics & Epidemiology Unit, Institute of Genetics and Cancer, University of Edinburgh 1 , Edinburgh, Scotland, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"Zaccai","sequence":"additional","affiliation":[{"name":"Sanofi 2 , Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oliver","family":"Guenther","sequence":"additional","affiliation":[{"name":"Sanofi 2 , Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonia","family":"Ridolfi","sequence":"additional","affiliation":[{"name":"Sanofi 2 , Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aymeric","family":"Mahieu","sequence":"additional","affiliation":[{"name":"Sanofi 2 , Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mireille","family":"Bonnemaire","sequence":"additional","affiliation":[{"name":"Sanofi 2 , Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8345-3288","authenticated-orcid":false,"given":"Helen M.","family":"Colhoun","sequence":"additional","affiliation":[{"name":"Diabetes Informatics & Epidemiology Unit, Institute of Genetics and Cancer, University of Edinburgh 1 , Edinburgh, Scotland, U.K."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1167","published-online":{"date-parts":[[2026,6,11]]},"reference":[{"key":"2026072014521708800_B1","doi-asserted-by":"crossref","first-page":"1486","DOI":"10.2337\/dc18-0465","article-title":"C-peptide decline in type 1 diabetes has two phases: an initial exponential fall and a subsequent stable phase","volume":"41","author":"Shields","year":"2018","journal-title":"Diabetes 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