{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,12]],"date-time":"2026-09-12T09:35:22Z","timestamp":1789205722422,"version":"build-2803163510"},"reference-count":50,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2015,1,23]],"date-time":"2015-01-23T00:00:00Z","timestamp":1421971200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Thuringian Ministry of Economy, Labor and Technology and European fund for regional development (EFRE)","award":["2014 KN 0018"],"award-info":[{"award-number":["2014 KN 0018"]}]},{"name":"Ernst-Abbe-Hochschule Jena","award":["2013"],"award-info":[{"award-number":["2013"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Schizophrenia is a severe mental disorder associated with a significantly  increased cardiovascular mortality rate. However, the underlying mechanisms leading to this cardiovascular disease (CVD) are not fully known. Therefore, the objective of this study was to characterize the cardiorespiratory influence by investigating heart rate, respiration and the causal strength and direction of cardiorespiratory coupling (CRC), based mainly on entropy measures. We investigated 23 non-medicated patients with schizophrenia (SZ), comparing them to 23 age- and gender-matched healthy controls (CO). A significantly reduced complexity was found for the heart rate and a significantly increased complexity in respiration and CRC in SZ patients when compared to corresponding measurements from CO (p &lt; 0.001). CRC analyses revealed a clear coupling, with a driver-responder relationship from respiration to heart rate in SZ patients. Moreover, a slight driver-responder relationship from heart rate to respiration could be recognized. These findings lead to the assumption that SZ should be considered to be a high-risk group for CVD. We hypothesize that the varying cardiorespiratory regulation contributes to the increased risk for cardiac mortality. Therefore, regular monitoring of the cardiorespiratory status of SZ is suggested to identify autonomic regulation impairment at an early stage\u2014to develop timely and effective treatment and intervention strategies.<\/jats:p>","DOI":"10.3390\/e17020483","type":"journal-article","created":{"date-parts":[[2015,1,23]],"date-time":"2015-01-23T11:20:34Z","timestamp":1422012034000},"page":"483-501","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Analyses of Heart Rate, Respiration and Cardiorespiratory Coupling in Patients with Schizophrenia"],"prefix":"10.3390","volume":"17","author":[{"given":"Steffen","family":"Schulz","sequence":"first","affiliation":[{"name":"Department of Medical Engineering and Biotechnology, University of Applied Sciences Jena,  Carl-Zeiss-Promenade 2, 07745 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karl-J\u00fcrgen","family":"B\u00e4r","sequence":"additional","affiliation":[{"name":"Department of Psychiatry and Psychotherapy, Pain and Autonomics-Integrative Research (PAIR), University Hospital Jena, Philosophenweg 3, 07743 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Voss","sequence":"additional","affiliation":[{"name":"Department of Medical Engineering and Biotechnology, University of Applied Sciences Jena,  Carl-Zeiss-Promenade 2, 07745 Jena, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1115","DOI":"10.1016\/j.ahj.2005.02.007","article-title":"Schizophrenia and increased risks of cardiovascular disease","volume":"150","author":"Hennekens","year":"2005","journal-title":"Am. 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