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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">cardiotomsk</journal-id><journal-title-group><journal-title xml:lang="ru">Сибирский журнал клинической и экспериментальной медицины</journal-title><trans-title-group xml:lang="en"><trans-title>Siberian Journal of Clinical and Experimental Medicine</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2713-2927</issn><issn pub-type="epub">2713-265X</issn><publisher><publisher-name>TSU publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.29001/2073-8552-2025-40-1-199-208</article-id><article-id custom-type="elpub" pub-id-type="custom">cardiotomsk-2648</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ЦИФРОВЫЕ ТЕХНОЛОГИИ В МЕДИЦИНЕ И ЗДРАВООХРАНЕНИИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>DIGITAL TECHNOLOGIES IN MEDICINE AND HEALTHCARE</subject></subj-group></article-categories><title-group><article-title>Определение предикторов неблагоприятного исхода в подострый период инфекции SARS-CoV-2 с помощью методов машинного обучения</article-title><trans-title-group xml:lang="en"><trans-title>Determination of predictors of an unfavorable outcome in the subacute period of SARS-CoV-2 infection using machine learning methods</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2658-0181</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Долгалёв</surname><given-names>И. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Dolgalev</surname><given-names>I. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Долгалёв Игорь Владимирович, д-р мед. наук, профессор, заведующий кафедрой факультетской терапии с курсом клинической фармакологии</p><p>634050, Томск, Московский тракт, 2</p></bio><bio xml:lang="en"><p>Igor V. Dolgalev, Dr. Sci. Med., Professor, Head of the Department of Faculty Therapy with a course in Clinical Pharmacology </p><p>2, Moskovskiy tract str., Tomsk, 634050</p></bio><email xlink:type="simple">dolgalev.iv@ssmu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-6915-6156</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Вражнов</surname><given-names>Д. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Vrazhnov</surname><given-names>D. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Вражнов Денис Александрович, научный сотрудник Научно-технологического центра «Цифровая медицина и киберфизика»</p><p>634050, Томск, Московский тракт, 2</p></bio><bio xml:lang="en"><p>Denis A. Vrazhnov, Research Scientist, Scientific and Technological Center “Digital Medicine and Cyberphysics” </p><p>2, Moskovskiy tract str., Tomsk, 634050</p></bio><email xlink:type="simple">vrazhnov.da@ssmu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2888-5539</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Толмачев</surname><given-names>И. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Tolmachev</surname><given-names>I. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Толмачев Иван Владиславович, канд. мед. наук, ведущий научный сотрудник, руководитель Научно-технологического центра «Цифровая медицина и киберфизика», СибГМУ, Томск, Россия; ведущий научный сотрудник, отдел научных основ организации здравоохранения, ЦНИИОИЗ</p><p>634050, Томск, Московский тракт, 2,</p><p>127254, Москва, ул. Вучетича, 12</p></bio><bio xml:lang="en"><p>Ivan V. Tolmachev, Cand. Sci. (Med.), Leading Research Scientist, Head of Scientific and Technological Center “Digital medicine and cyberphysics” of SSMU; Senior Research Fellow, Division of Health Sciences, Russian Research Institute of Health</p><p>2, Moskovskiy tract str., Tomsk, 634050,</p><p>11, Dobrolubova, Moscow,127254</p></bio><email xlink:type="simple">tolmachev.iv@ssmu.ru</email><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8899-0795</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Старикова</surname><given-names>Е. Г.</given-names></name><name name-style="western" xml:lang="en"><surname>Starikova</surname><given-names>E. G.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Старикова Елена Григорьевна, д-р мед. наук, ведущий научный сотрудник, Научно-технологический центр «Цифровая медицина и киберфизика»</p><p>634050, Томск, Московский тракт, 2</p></bio><bio xml:lang="en"><p>Elena G. Starikova, Dr. Sci. (Med.), Leading Research Scintist, Scientific and Technological Center “Digital Medicine and Cyberphysics”, </p><p>2, Moskovskiy tract str., Tomsk, 634050</p></bio><email xlink:type="simple">elena.g.starikova@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9748-482X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Каверина</surname><given-names>И. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Kaverina</surname><given-names>I. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Каверина Ирина Сергеевна, научный сотрудник, Научно-технологический центр «Цифровая медицина и киберфизика»</p><p>634050, Томск, Московский тракт, 2</p></bio><bio xml:lang="en"><p>Irina S. Kaverina, Research Scientist, Scientific and Technological Center “Digital medicine and cyberphysics” </p><p>2, Moskovskiy tract str., Tomsk, 634050</p></bio><email xlink:type="simple">kaverina.is@ssmu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9429-9813</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Завьялова</surname><given-names>М. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Zavyalova</surname><given-names>M. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Завьялова Марина Викторовна, д-р мед. наук, профессор, заведующий кафедрой патологической анатомии </p><p>634050, Томск, Московский тракт, 2</p></bio><bio xml:lang="en"><p>Marina V. Zavyalova, Dr. Sci. (Med.), Professor, Head of the Department of Pathological Anatomy</p><p>2, Moskovskiy tract str., Tomsk, 634050</p></bio><email xlink:type="simple">zavyalova.mv@ssmu.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Сибирский государственный медицинский университет Министерства здравоохранения Российской Федерации (СибГМУ Минздрава России)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Siberian State Medical University of the Ministry of Health of the Russian Federation (SSMU)</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Сибирский государственный медицинский университет Министерства здравоохранения Российской Федерации (СибГМУ Минздрава России); Центральный научно-исследовательский институт организации и информатизации здравоохранения (ЦНИИОИЗ)</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Siberian State Medical University of the Ministry of Health of the Russian Federation (SSMU);&#13;
Russian Research Institute of Health</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2025</year></pub-date><pub-date pub-type="epub"><day>13</day><month>04</month><year>2025</year></pub-date><volume>40</volume><issue>1</issue><fpage>199</fpage><lpage>208</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Долгалёв И.В., Вражнов Д.А., Толмачев И.В., Старикова Е.Г., Каверина И.С., Завьялова М.В., 2025</copyright-statement><copyright-year>2025</copyright-year><copyright-holder xml:lang="ru">Долгалёв И.В., Вражнов Д.А., Толмачев И.В., Старикова Е.Г., Каверина И.С., Завьялова М.В.</copyright-holder><copyright-holder xml:lang="en">Dolgalev I.V., Vrazhnov D.A., Tolmachev I.V., Starikova E.G., Kaverina I.S., Zavyalova M.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.sibjcem.ru/jour/article/view/2648">https://www.sibjcem.ru/jour/article/view/2648</self-uri><abstract><sec><title>Введение</title><p>Введение. Патологические изменения систем и органов после перенесенного COVID-19 могут приводить к отложенному смертельному исходу. При этом одной из особенно значимых систем-мишеней постковидных изменений является кардиоваскулярная система.</p></sec><sec><title>Цель исследования</title><p>Цель исследования: выявление с помощью методов машинного обучения (МО) показателей, имеющих прогностическую ценность при определении неблагоприятного исхода подострого COVID-19.</p></sec><sec><title>Материал и методы</title><p>Материал и методы. В исследование были включены 212 человек, госпитализированных после перенесенного ранее в тяжелой форме COVID-19. Ретроспективно пациенты были разделены на 2 группы: 140 пациентов, которые были выписаны из стационара с заключением об улучшении состояния, и 72 пациента, умершие в период госпитализации. Всем пациентам проводились общеклинический, биохимический анализы, оценка свертывающей системы крови. Для анализа данных были использованы следующие методы МО: метод опорных векторов, случайный лес, стохастический градиентный бустинг. Валидация полученных моделей производилась методом перекрестной 10-кратной проверки совместно с ROC-AUC анализом (Receiver Operation Characteristics – Area Under Curve).</p></sec><sec><title>Результаты</title><p>Результаты. В созданных нами предиктивных моделях предикторами смертельного исхода для методов случайный лес и стохастический градиентный бустинг являлись мочевина и температура тела; для машины опорных векторов – количество эритроцитов, эозинофилов и моноцитов, международное нормализованное отношение (МНО).</p></sec><sec><title>Выводы</title><p>Выводы. В проведенном исследовании две предиктивные модели, созданные с помощью методов МО, случайный лес и стохастический градиентный бустинг, показали, что прогностическое значение имеют изменения двух показателей: уровня мочевины и температуры тела. Метод опорных векторов выявил другие предикторы, а именно количество эритроцитов, эозинофилов и моноцитов, МНО. Нами был применен метод голосования, на основе которого в качестве информативных признаков были установлены уровень мочевины и температура тела. Методы МО случайный лес и стохастический градиентный бустинг продемонстрировали схожие результаты, мы не учитывали данные, полученные с помощью метода опорных векторов. Подобный подход выбора предиктивной модели голосованием часто используется при оценке данных методами искусственного интеллекта. Возможно, повышение уровня мочевины являлось пусковым механизмом, ведущим к эндотелииту и последующему инфаркту миокарда, до того, как развилась острая почечная недостаточность.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Background</title><p>Background. Pathological changes in systems and organs after COVID-19 can lead to delayed death. One of the most influenced target systems of post-COVID changes is the cardiovascular system.</p></sec><sec><title>Aim</title><p>Aim: To identify, using machine learning methods, indicators that have predictive value in determining the adverse outcome of subacute COVID-19.</p></sec><sec><title>Material and Methods</title><p>Material and Methods. The study included 212 people admitted after previous severe COVID-19. Retrospectively, the patients were divided into 2 groups: 140 patients discharged from the hospital after improvement in their state and 72 patients died during hospitalization. All patients underwent general clinical, biochemical analyses, assessment of blood coagulation system. The following machine learning methods were used for data analysis: support vector machine, random forest, stochastic gradient boosting. Validation of the obtained models was carried out by the method of 10-fold cross-validation in conjunction with ROC–AUC analysis (Receiver Operation Characteristics – Area Under Curve).</p></sec><sec><title>Results</title><p>Results. In the created models, the predictors of mortality were urea and body temperature for the random forest and stochastic gradient boosting methods, erythrocyte, eosinophil and monocyte counts, and INR (International Normalized Ratio) level for the support vector machine.</p></sec><sec><title>Conclusion</title><p>Conclusion. In our study, two predictive models created using machine learning methods random forest and stochastic gradient boosting showed that changes in urea level and body temperature had predictive value. The support vector machine revealed other predictors, namely the number of erythrocytes, eosinophils and monocytes, INR. We used the voting method, on the basis of which the urea level and body temperature were established as informative signs. The random forest and stochastic gradient boosting methods showed similar results, we did not take into account the data obtained using the support vector machine. This approach of choosing a predictive model by voting is often used when evaluating data using artificial intelligence methods. It is possible that an increase in urea levels was a trigger leading to endotheliitis and subsequent myocardial infarction, before acute renal failure developed.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>COVID-19</kwd><kwd>постковидные изменения</kwd><kwd>машинное обучение</kwd><kwd>мочевина</kwd><kwd>температура тела</kwd><kwd>количество эритроцитов</kwd><kwd>количество эозинофилов</kwd><kwd>количество моноцитов</kwd><kwd>международное нормализованное отношение</kwd><kwd>сердечно-сосудистая система</kwd></kwd-group><kwd-group xml:lang="en"><kwd>COVID-19</kwd><kwd>post-COVID changes</kwd><kwd>machine learning</kwd><kwd>urea</kwd><kwd>body temperature</kwd><kwd>erythrocyte count</kwd><kwd>eosinophil count</kwd><kwd>monocyte count</kwd><kwd>International Normalized Ratio</kwd><kwd>cardiovascular system</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Nalbandian A., Sehgal K., Gupta A., Madhavan M.V., McGroder C., Stevens J.S. et al. 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