{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,19]],"date-time":"2025-10-19T16:00:52Z","timestamp":1760889652336,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,6,27]],"date-time":"2018-06-27T00:00:00Z","timestamp":1530057600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61461001"],"award-info":[{"award-number":["61461001"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>The present study aimed at testing the hypothesis that application of multiscale cross-approximate entropy (MCAE) analysis in the study of nonlinear coupling behavior of two synchronized time series of different natures [i.e., R-R interval (RRI) and crest time (CT, the time interval from foot to peakof a pulse wave)] could yield information on complexity related to diabetes-associated vascular changes. Signals of a single waveform parameter (i.e., CT) from photoplethysmography and RRI from electrocardiogram were simultaneously acquired within a period of one thousand cardiac cycles for the computation of different multiscale entropy indices from healthy young adults (n = 22) (Group 1), upper-middle aged non-diabetic subjects (n = 34) (Group 2) and diabetic patients (n = 34) (Group 3). The demographic (i.e., age), anthropometric (i.e., body height, body weight, waist circumference, body-mass index), hemodynamic (i.e., systolic and diastolic blood pressures), and serum biochemical (i.e., high- and low-density lipoprotein cholesterol, total cholesterol, and triglyceride) parameters were compared with different multiscale entropy indices including small- and large-scale multiscale entropy indices for CT and RRI [MEISS(CT), MEILS(CT), MEISS(RRI), MEILS(RRI), respectively] as well as small- and large-scale multiscale cross-approximate entropy indices [MCEISS, MCEILS, respectively]. The results demonstrated that both MEILS(RRI) and MCEILS significantly differentiated between Group 2 and Group 3 (all p &lt; 0.017). Multivariate linear regression analysis showed significant associations of MEILS(RRI) and MCEILS(RRI,CT) with age and glycated hemoglobin level (all p &lt; 0.017). The findings highlight the successful application of a novel multiscale cross-approximate entropy index in non-invasively identifying diabetes-associated subtle changes in vascular functional integrity, which is of clinical importance in preventive medicine.<\/jats:p>","DOI":"10.3390\/e20070497","type":"journal-article","created":{"date-parts":[[2018,6,27]],"date-time":"2018-06-27T11:02:05Z","timestamp":1530097325000},"page":"497","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Combination of R-R Interval and Crest Time in Assessing Complexity Using Multiscale Cross-Approximate Entropy in Normal and Diabetic Subjects"],"prefix":"10.3390","volume":"20","author":[{"given":"Ming-Xia","family":"Xiao","sequence":"first","affiliation":[{"name":"School of Electrical and Information Engineering, North Minzu University, No. 204 North\u2014Wenchang St., Xixia District, Yinchuan 750021, China"},{"name":"School of Computer and Information, Hefei University of Technology, No. 193, Tunxi Rd., Hefei 230009, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hai-Cheng","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, North Minzu University, No. 204 North\u2014Wenchang St., Xixia District, Yinchuan 750021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ya-Jie","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, North Minzu University, No. 204 North\u2014Wenchang St., Xixia District, Yinchuan 750021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2581-9384","authenticated-orcid":false,"given":"Hsien-Tsai","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering, National Dong Hwa University, No. 1, Sec. 2, Da Hsueh Rd., Shoufeng, Hualien 97401, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2524-9684","authenticated-orcid":false,"given":"Cheuk-Kwan","family":"Sun","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, E-Da Hospital, I-Shou University School of Medicine for International Students, No.1, Yida Road, Jiaosu Village, Yanchao District, Kaohsiung City 82445, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.pop.2017.11.001","article-title":"State of the Heart: An Overview of the Disease Burden of Cardiovascular Disease from an Epidemiologic Perspective","volume":"45","author":"Lennon","year":"2018","journal-title":"Prim. 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