<?xml version="1.0" encoding="ISO-8859-1"?><article 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">
<front>
<journal-meta>
<journal-id>0016-3813</journal-id>
<journal-title><![CDATA[Gaceta médica de México]]></journal-title>
<abbrev-journal-title><![CDATA[Gac. Méd. Méx]]></abbrev-journal-title>
<issn>0016-3813</issn>
<publisher>
<publisher-name><![CDATA[Academia Nacional de Medicina de México A.C.]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S0016-38132022000100032</article-id>
<article-id pub-id-type="doi">10.24875/gmm.21000390</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Evaluación de la utilidad de la vitamina D como predictor de mortalidad en pacientes con COVID-19]]></article-title>
<article-title xml:lang="en"><![CDATA[Evaluation of the usefulness of vitamin D as a predictor of mortality in patients with COVID-19]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Martínez-Rodríguez]]></surname>
<given-names><![CDATA[Erick J.]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Gutiérrez-Mejía]]></surname>
<given-names><![CDATA[Juan]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Ríos-Castañeda]]></surname>
<given-names><![CDATA[Camilo]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Rojas-Maya]]></surname>
<given-names><![CDATA[Sonia]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Soto-Mota]]></surname>
<given-names><![CDATA[Adrián]]></given-names>
</name>
<xref ref-type="aff" rid="Aff"/>
</contrib>
</contrib-group>
<aff id="Af1">
<institution><![CDATA[,Instituto Nacional de Ciencias Médicas y Nutrición &#8220;Salvador Zubirán&#8221; Departamento de Reacción Hospitalaria para Desastres ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af2">
<institution><![CDATA[,Instituto Nacional de Neurología y Neurocirugía &#8220;Manuel Velasco Suárez&#8221; Departamento de Neuroquímica ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>México</country>
</aff>
<aff id="Af3">
<institution><![CDATA[,Instituto Nacional de Ciencias Médicas y Nutrición &#8220;Salvador Zubirán&#8221; Departamento de Laboratorio Clínico ]]></institution>
<addr-line><![CDATA[Ciudad de México ]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>02</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>02</month>
<year>2022</year>
</pub-date>
<volume>158</volume>
<numero>1</numero>
<fpage>32</fpage>
<lpage>37</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S0016-38132022000100032&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S0016-38132022000100032&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S0016-38132022000100032&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Resumen  Introducción: Una de las funciones de la vitamina D es regular la respuesta inflamatoria del epitelio respiratorio; por ello, la deficiencia de esa vitamina en el contexto de COVID-19 podría constituir un biomarcador preditivo del desenlace de COVID-19.  Objetivo: Evaluar la utilidad de la vitamina D para predecir la mortalidad en pacientes con COVID-19.  Métodos: Estudio observacional y retrospectivo en el que se incluyeron 154 pacientes con diagnóstico de COVID-19, de los cuales 111 sobrevivieron y 43 fallecieron. En todos se determinó la concentración de vitamina D.  Resultados: Se obtuvo un valor log-rank de p &lt; 0.032 para la supervivencia al utilizar la concentración de vitamina D como variable categórica (&#8804; 20 ng/mL y &gt; 20 ng/mL). Mediante análisis proporcional de Cox se encontró que la edad y concentración de vitamina D mostraron ser factores de riesgo asociados a la mortalidad en pacientes con COVID-19 (edad: HR = 1.036, IC 95 % = 1.016-1.058, p &lt; 0.001; vitamina D: HR &#8804; 20 ng/mL y &gt; 20 ng/mL = 0.478, IC 95 % = 0.237-0.966, p &lt; 0.040).  Conclusión: La edad y la concentración de vitamina D constituyeron factores predictivos de mortalidad en pacientes infectados por COVID-19.]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[Abstract  Introduction: One of the functions of vitamin D is to regulate respiratory epithelium inflammatory response; therefore, deficiency of this vitamin in the context of COVID-19 could constitute a predictive biomarker of the disease outcome.  Objective: To evaluate the usefulness of vitamin D for predicting mortality in patients with COVID-19.  Methods: Observational, retrospective study in which 154 patients diagnosed with COVID-19 were included, out of whom 111 survived and 43 died. Vitamin D concentration was determined in all of them.  Results: A log-rank p-value &lt; 0.032 was obtained for survival when vitamin D concentration was used as a categorical variable (&#8804; 20 ng/mL and &gt; 20 ng/mL). On Cox proportional analysis, age and vitamin D concentration were shown to be risk factors associated with mortality in patients with COVID-19 (age: HR = 1.036, 95% CI = 1.016-1.058, p &lt; 0.001; vitamin D: HR [&#8804; 20 ng/mL and &gt; 20 ng/mL] = 0.478, 95% CI = 0.237-0.966, p &lt; 0.040).  Conclusion: Age and vitamin D concentration were predictive factors for mortality in COVID-19-infected patients.]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Vitamina D]]></kwd>
<kwd lng="es"><![CDATA[COVID-19]]></kwd>
<kwd lng="es"><![CDATA[Respuesta inflamatoria del epitelio respiratorio]]></kwd>
<kwd lng="es"><![CDATA[Factor predictivo]]></kwd>
<kwd lng="en"><![CDATA[Vitamin D]]></kwd>
<kwd lng="en"><![CDATA[COVID-19]]></kwd>
<kwd lng="en"><![CDATA[Respiratory epithelium inflammatory response]]></kwd>
<kwd lng="en"><![CDATA[Predictive factor]]></kwd>
</kwd-group>
</article-meta>
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