{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T01:56:52Z","timestamp":1793239012301,"version":"4.5.0"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,4]],"date-time":"2023-01-04T00:00:00Z","timestamp":1672790400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Austrian National Bank","award":["13878"],"award-info":[{"award-number":["13878"]}]},{"name":"Austrian National Bank","award":["13905"],"award-info":[{"award-number":["13905"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Accumulating evidence suggests an association of the tryptophan\u2013kynurenine (TRP-KYN) pathway with atherosclerosis and cardiovascular risk factors. In this cross-sectional analysis we investigated whether TRP-KYN pathway parameters are associated with 24 h blood pressure (BP) and other risk factors in patients with arterial hypertension from a tertiary care centre. In 490 participants, we found no significant and independent association of 24 h systolic and diastolic BP with parameters of the TRP-KYN pathway. However, linear regression analyses of HDL as dependent and TRP, KYN and quinolinic acid (QUIN) as explanatory variables adjusted for BMI and sex showed significant associations. These were found for KYN, BMI and sex (unstandardised beta coefficient \u22120.182, standard error 0.052, p &lt; 0.001; \u22120.313 (0.078), p &lt; 0.001; \u22120.180 (0.024), p &lt; 0.001, respectively) as well as for QUIN, BMI and sex (\u22120.157 (0.038), p &lt; 0.001; \u22120.321 (0.079), p &lt; 0.001; \u22120.193 (0.024), p &lt; 0.001, respectively). Smokers had significantly lower levels of KYN (2.36 \u00b5mol\/L, IQR 2.01\u20132.98, versus 2.71 \u00b5mol\/L, IQR 2.31\u20133.27, p &lt; 0.001), QUIN (384 nmol\/L, IQR 303\u2013448, versus 451 nmol\/L, IQR 369\u2013575, p &lt; 0.001) and KYN\/TRP ratio (38.2, IQR 33.7\u201343.2, versus 43.1, IQR 37.5\u201350.9, p &lt; 0.001) compared to non-smokers. We demonstrated that TRP\/KYN pathway metabolites are associated with some cardiovascular risk factors, warranting further studies to elucidate the diagnostic and therapeutic potential of the TRP-KYN pathway for cardiovascular diseases.<\/jats:p>","DOI":"10.3390\/nu15020256","type":"journal-article","created":{"date-parts":[[2023,1,4]],"date-time":"2023-01-04T02:54:55Z","timestamp":1672800895000},"page":"256","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Associations of Parameters of the Tryptophan\u2013Kynurenine Pathway with Cardiovascular Risk Factors in Hypertensive Patients"],"prefix":"10.3390","volume":"15","author":[{"given":"Verena","family":"Theiler-Schwetz","sequence":"first","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Trummer","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1761-2914","authenticated-orcid":false,"given":"Martin R.","family":"Gr\u00fcbler","sequence":"additional","affiliation":[{"name":"Regional Hospital Wiener Neustadt, 2700 Wiener Neustadt, Austria"},{"name":"Department of Aging Medicine and Aging Research, University of Zurich, 8006 Zurich, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martin H.","family":"Keppel","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Paracelsus Medical University Salzburg, 5020 Salzburg, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6085-6554","authenticated-orcid":false,"given":"Armin","family":"Zittermann","sequence":"additional","affiliation":[{"name":"Clinic for Thoracic and Cardiovascular Surgery, Herz-und Diabeteszentrum Nordrhein-Westfalen (NRW), Ruhr University Bochum, 32545 Bad Oeynhausen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Tomaschitz","sequence":"additional","affiliation":[{"name":"Health Center Trofaiach-G\u00f6ssgrabenstrasse, 8793 Trofaiach, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6083-8946","authenticated-orcid":false,"given":"Winfried","family":"M\u00e4rz","sequence":"additional","affiliation":[{"name":"SYNLAB Academy, Synlab Holding Deutschland GmbH, 68159 Mannheim, Germany"},{"name":"Vth Department of Medicine (Nephrology, Hypertensiology, Rheumatology, Endocrinology, Diabetology, Lipidology), Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany"},{"name":"Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Meinitzer","sequence":"additional","affiliation":[{"name":"Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Pilz","sequence":"additional","affiliation":[{"name":"Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, 8036 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,4]]},"reference":[{"key":"ref_1","first-page":"e9349","article-title":"Global Epidemiology of Ischemic Heart Disease: Results from the Global Burden of Disease Study","volume":"12","author":"Khan","year":"2020","journal-title":"Cureus"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1931","DOI":"10.2174\/0929867321666140304105526","article-title":"Disturbed Tryptophan Metabolism in Cardiovascular Disease","volume":"21","author":"Mangge","year":"2014","journal-title":"Curr. 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