{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T16:50:09Z","timestamp":1777308609439,"version":"3.51.4"},"reference-count":51,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2023,12,3]],"date-time":"2023-12-03T00:00:00Z","timestamp":1701561600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"INFOTEC"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Bradycardia, frequently observed in preterm infants, presents significant risks due to the immaturity of their autonomic nervous system (ANS) and respiratory systems. These infants may face cardiorespiratory events, leading to severe complications like hypoxemia and neurodevelopmental disorders. Although neonatal care has advanced, the influence of bradycardia on cardiorespiratory coupling (CRC) remains elusive. This exploratory study delves into CRC in preterm infants, emphasizing disparities between events with and without bradycardia. Using the Preterm Infant Cardio-Respiratory Signals (PICS) database, we analyzed interbeat (R-R) and inter-breath intervals (IBI) from 10 preterm infants. The time series were segmented into bradycardic (B) and non-bradycardic (NB) segments. Employing information theory measures, we quantified the irregularity of cardiac and respiratory time series. Notably, B segments had significantly lower entropy values for R-R and IBI than NB segments, while mutual information was higher in NB segments. This could imply a reduction in the complexity of respiratory and cardiac dynamics during bradycardic events, potentially indicating weaker CRC. Building on these insights, this research highlights the distinctive physiological characteristics of preterm infants and underscores the potential of emerging non-invasive diagnostic tools.<\/jats:p>","DOI":"10.3390\/e25121616","type":"journal-article","created":{"date-parts":[[2023,12,4]],"date-time":"2023-12-04T03:40:58Z","timestamp":1701661258000},"page":"1616","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Bradycardia May Decrease Cardiorespiratory Coupling in Preterm Infants"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7524-5833","authenticated-orcid":false,"given":"Miguel \u00c1ngel","family":"Porta-Garc\u00eda","sequence":"first","affiliation":[{"name":"Center of Research and Innovation in Information Technology and Communication\u2014INFOTEC, Mexico City 14050, Mexico"},{"name":"School of Medicine, Autonomous University of the State of Mexico (UAEM\u00e9x), Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alberto","family":"Quiroz-Salazar","sequence":"additional","affiliation":[{"name":"School of Medicine, Autonomous University of the State of Mexico (UAEM\u00e9x), Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eric Alonso","family":"Abarca-Castro","sequence":"additional","affiliation":[{"name":"Department of Health Sciences, Metropolitan Autonomous University-Lerma (UAM-L), Lerma de Villada 52005, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5361-5007","authenticated-orcid":false,"given":"Jos\u00e9 Javier","family":"Reyes-Lagos","sequence":"additional","affiliation":[{"name":"School of Medicine, Autonomous University of the State of Mexico (UAEM\u00e9x), Toluca de Lerdo 50180, Mexico"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,3]]},"reference":[{"key":"ref_1","unstructured":"WHO (2023, September 01). 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