RESUMEN
Objective: To identify and quantify the effects of maternal characteristics and medical history on the distribution of Placental Growth Factor (PlGF), mean arterial pressure (MAP), and Uterine Artery Mean Pulsatility Index (UtA-PI); and to standardize the expected values for these biomarkers in the first trimester to create unique multiples of the median (MoMs) for Latin-American population. Methods: This is a prospective cohort built exclusively for research purposes of consecutive pregnant women attending their first-trimester screening ultrasound at a primary care center for the general population in Mexico City between April 2019 and October 2021. We excluded fetuses with chromosomal abnormalities, major fetal malformations, and women delivering in another care center. Linear regression was used on log-transformed biomarkers to assess the influence of maternal characteristics on non-preeclamptic women to create MoM. Results: Of a total of 2,820 pregnant women included in the final analysis, 118 (4.18%) developed PE, of which 22 (0.78%) delivered before 34 weeks of gestation, 74 (2.62%) before 37 weeks, and 44 (1.56%) from 37 weeks gestation. Characteristics that significantly influenced PLGF were fetal crown rump length (CRL), maternal age, nulliparity, body mass index (BMI), chronic hypertension, Lupus, spontaneous pregnancy, polycystic ovary syndrome (PCOS), hypothyroidism, preeclampsia (PE) in a previous pregnancy, and mother with PE. MAP had significant influence from CRL, maternal age, PE in a previous pregnancy, induction of ovulation, a mother with PE, chronic hypertension, BMI, and hypothyroidism. UtA-PI was influenced by CRL, maternal age, a mother with PE, chronic hypertension, and gestational diabetes mellitus (GDM) in a previous pregnancy. Conclusion: Population-specific multiples of the median (MoMs) for PlGF, MAP, and UtA-PI in the first trimester adequately discriminate among women developing preeclampsia later in pregnancy.
RESUMEN
Resumen OBJETIVO: Calcular y ajustar los múltiplos de la mediana para el índice de pulsatilidad medio de las arterias uterinas, presión arterial media materna, factor de crecimiento placentario y proteína plasmática A asociada al embarazo, a fin de valorar el desempeño diagnóstico del modelo corregido de preeclampsia de la Fetal Medicine Foundation en población mexicana. MATERIALES Y MÉTODOS: Estudio de casos y controles anidado en una cohorte prospectiva efectuado en el Centro de Salud Dr. Galo Soberón y Parra entre el 1 de octubre de 2015 y el 30 de junio de 2016. Criterio de inclusión: pacientes con embarazo de 11-13.6 semanas. Criterio de exclusión: pacientes de riesgo no seleccionado, con embarazo único, entre 11 y 13.6 semanas calculadas por ecografía mediante longitud cráneo cauda. Criterio de eliminación: pacientes que abandonaron el estudio. Se evaluaron el índice de pulsatilidad medio de las arterias uterinas, la presión arterial media, los valores séricos del factor de crecimiento placentario y la proteína plasmática A asociada al embarazo. Se comparó la diferencia en la distribución de los biomarcadores entre la observada en población mexicana y la esperada según la formula original de la Fetal Medicine Foundation. Cuando la diferencia fue mayor a 0.2 múltiplos de la mediana, se utilizó la mediana del observado como coeficiente de ajuste a la fórmula original del esperado. RESULTADOS: De las 300 pacientes reclutadas, 292 concluyeron el estudio. La media de semanas de embarazo al momento del tamizaje fue de 12.4 (desviación estándar 0.72). La prevalencia de preeclampsia fue de 4.5% (13 de 292). Se encontraron diferencias importantes en la distribución de múltiplos de la mediana para el índice de pulsatilidad medio de las arterias uterinas, factor de crecimiento placentario y proteína plasmática A asociada al embarazo. Posterior a la corrección de los biomarcadores, la sensibilidad, falsos positivos y área bajo la curva del modelo ajustado para detectar cualquier preeclampsia fue de 92% (12 de 13), 5.7% (16 de 279) y 93.3%, respectivamente. CONCLUSIONES: La distribución de los múltiplos de la mediana en población mexicana es distinta para los biomarcadores: factor de crecimiento placentario, proteína plasmática A asociada al embarazo e índice de pulsatilidad medio de las arterias uterinas. El ajuste de estos biomarcadores para población mexicana resulta en un buen desempeño diagnóstico del modelo de preeclampsia.
Abstract OBJECTIVE: Calculate and adjust the multiples of the median (MoMs) for the mean pulsatility index of uterine arteries (IPm Aut), mean arterial pressure (PAM), placental growth factor (PlGF) and plasma protein associated with pregnancy (PAPP-A), in order to assess the diagnostic performance of the corrected preeclampsia model of the fetal medicine foundation in the Mexican population. MATERIALS AND METHODS: Case-control study nested in a prospective cohort conducted at the "Dr. Galo Soberón y Parra "from October 1, 2015 - June 30, 2016. Patients with pregnancy of 11-13.6 weeks were included, multiple pregnancies or older than 14 weeks were excluded and patients with medication intake prior to pregnancy; Patients who decided to leave the study were eliminated. Autm IPm, PAM, PlGF and PAPP-A serum values were evaluated. The difference in the distribution of biomarkers between that observed in the Mexican population and that expected was compared according to the original formula of the Fetal Medicine Foundation. When the difference was greater than 0.2 MoMs, the median observed was used as an adjustment coefficient to the original expected formula. RESULTS: Of the 300 patients recruited, 292 concluded the study. The average gestational age at the time of screening was 12.4 weeks (standard deviation [SD] 0.72). The prevalence of preeclampsia was 4.5% (13/292). Important differences were found in the distribution of multiples of the median (MoMs) for IPm Aut, PlGF and PAPP-A. After correction of the biomarkers, the sensitivity, false positives and area under the curve (AUC) of the model adjusted to detect any preeclampsia was 92% (12/13), 5.7% (16/279) and 93.3%, respectively . CONCLUSIONS: The distribution of MoMs in the Mexican population is different for the PlGF, PAPP-A and IPm Aut biomarkers. The adjustment of these biomarkers to the Mexican population results in a good diagnostic performance of the preeclampsia model.
