{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T01:39:10Z","timestamp":1790127550882,"version":"4.0.1"},"reference-count":40,"publisher":"American Diabetes Association","issue":"12","license":[{"start":{"date-parts":[[2023,2,14]],"date-time":"2023-02-14T00:00:00Z","timestamp":1676332800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.diabetesjournals.org\/journals\/pages\/license"}],"funder":[{"name":"UAB Diabetes Research Center","award":["P30DK079626"],"award-info":[{"award-number":["P30DK079626"]}]},{"name":"National Heart, Lung, and Blood Institute of the National Institutes of Health","award":["T32HL105349"],"award-info":[{"award-number":["T32HL105349"]}]},{"name":"Center for Clinical and Translational Science"},{"name":"National Institute of Diabetes and Digestive and Kidney Diseases at the National Institutes of Health","award":["R01DK096388"],"award-info":[{"award-number":["R01DK096388"]}]},{"DOI":"10.13039\/100017553","name":"UAB Nutrition Obesity Research Center","doi-asserted-by":"crossref","award":["P30DK56336"],"award-info":[{"award-number":["P30DK56336"]}],"id":[{"id":"10.13039\/100017553","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["diabetesjournals.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2023,12,1]]},"abstract":"<jats:sec>\n                  <jats:title>OBJECTIVE<\/jats:title>\n                  <jats:p>The primary purpose of the current study was to test the hypothesis that the proinsulin\u2013to\u2013C-peptide (PI-to-CP) ratio, as an index of proinsulin secretion, would be higher and associated with indices of \u03b2-cell function in African American adults relative to European American adults without type 2 diabetes.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>RESEARCH DESIGN AND METHODS<\/jats:title>\n                  <jats:p>Participants were 114 African American and European American adult men and women. A 2-h oral glucose tolerance test was conducted to measure glucose, insulin, C-peptide, and proinsulin and derive indices of \u03b2-cell response to glucose. The Matsuda index was calculated as a measure of insulin sensitivity. The disposition index (DI), the product of insulin sensitivity and \u03b2-cell response, was calculated for each phase of \u03b2-cell responsivity. Pearson correlations were used to investigate the relationship of the PI-to-CP ratio with each phase of \u03b2-cell response (basal, \u03a6b; dynamic, \u03a6d; static, \u03a6s; total, \u03a6tot), disposition indices (DId, DIs, DItot), and insulin sensitivity. Multiple linear regression analysis was used to evaluate independent contributions of race, BMI, and glucose tolerance status on PI-to-CP levels before and after adjustment for insulin sensitivity.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>RESULTS<\/jats:title>\n                  <jats:p>African American participants had higher fasting and 2-h PI-to-CP ratios. The fasting PI-to-CP ratio was positively associated with \u03a6b, and the fasting PI-to-CP ratio and 2-h PI-to-CP ratio were inversely associated with DId and insulin sensitivity only in African American participants.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>CONCLUSIONS<\/jats:title>\n                  <jats:p>The PI-to-CP ratio could be useful in identifying African American individuals at highest risk for \u03b2-cell dysfunction and ultimately type 2 diabetes.<\/jats:p>\n               <\/jats:sec>","DOI":"10.2337\/dc22-1763","type":"journal-article","created":{"date-parts":[[2023,2,15]],"date-time":"2023-02-15T00:50:31Z","timestamp":1676422231000},"page":"2129-2136","update-policy":"https:\/\/doi.org\/10.2337\/ada-journal-policies","source":"Crossref","is-referenced-by-count":14,"title":["Proinsulin\u2013to\u2013C-Peptide Ratio as a Marker of \u03b2-Cell Function in African American and European American Adults"],"prefix":"10.2337","volume":"46","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4568-8609","authenticated-orcid":false,"given":"Catharine A.","family":"Couch","sequence":"first","affiliation":[{"name":"Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"Piccinini","sequence":"additional","affiliation":[{"name":"Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren A.","family":"Fowler","sequence":"additional","affiliation":[{"name":"Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"W. Timothy","family":"Garvey","sequence":"additional","affiliation":[{"name":"Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Barbara A.","family":"Gower","sequence":"additional","affiliation":[{"name":"Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1167","published-online":{"date-parts":[[2023,2,14]]},"reference":[{"key":"2023112719541620400_B1","doi-asserted-by":"crossref","first-page":"107843","DOI":"10.1016\/j.diabres.2019.107843","article-title":"Global and regional diabetes prevalence estimates for 2019 and projections for 2030 and 2045: results from the International Diabetes Federation Diabetes Atlas, 9th edition","volume":"157","author":"Saeedi","year":"2019","journal-title":"Diabetes Res Clin Pract"},{"key":"2023112719541620400_B2","unstructured":"Centers for Disease Control and Prevention\n          . 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