Correlation of plasma prolactin and cortisol with vasovagal syncope in children / 中华实用儿科临床杂志

ABSTRACT

Objective:To investigate the changes of plasma prolactin (PRL) and cortisol (Cor) in the head up tilt test (HUT) in children with vasovagal syncope (VVS), and their correlation with VVS.Methods:From May 2019 to May 2020, 75 children diagnosed as VVS through positive HUT in the Children′s Hospital, Capital Institute of Pediatrics were retrospectively recruited as VVS group, while 29 healthy children with negative HUT during the same period were collected in healthy control group.Heart rate (HR) and blood pressure [systolic and diastolic blood pressure (SBP, DBP)] were monitored using a noninvasive continuous blood pressure monitor.The changes of HR, SBP and DBP were analyzed and their differences between the supine position and positive reaction of HUT were compared.The contents of PRL and Cor in the supine position and positive reaction of HUT were measured using the electrochemiluminescence, and their changes (ΔPRL and ΔCor) were calculated.Differences between groups were analyzed by the two-tailed Student′s t-test or the Mann- Whitney test.Receiver operating characteristic (ROC) curves were plotted to analyze the predictive value of ΔPRL on VVS. Results:There were no significant differences in the age, gender, body mass index, blood electrolyte, syncope frequency and syncope course between VVS group and healthy control group (all P>0.05). There was no significant difference in syncope frequency and course of syncope among subtypes of VVS group (vasodepressor syncope, mixed syncope, cardioinhibitory syncope)(all P>0.05). Compared with healthy control group, PRL after HUT was significantly higher in VVS group[36.23 (22.08, 61.97) μg/L vs.11.47 (8.00, 23.25 ) μg/L, Z=-5.40, P<0.01]. Both ΔPRL [25.36( 9.92, 48.93) μg/L vs.-0.10(- 2.67, 9.32) μg/L, Z=-5.39, P<0.01] and ΔCor [(84.4±43.6) μg/L vs.(57.6±64.6) μg/L, t=-2.44, P<0.05 ] were significantly higher in VVS group than those of healthy control group.PRL at HUT positive reaction was negatively correlated with SBP and DBP ( r=- 0.46, -0.45, all P<0.01). In VVS group, PRL at HUT positive reaction was negatively correlated with SBP ( r=-0.38, -0.24, all P<0.05). In VVS group, ΔCor after HUT was negatively correlated with SBP ( r=-0.25, P<0.05). ROC curves revealed that the cut-off value of ΔPRL in predicting HUT was 4.03 μg/L, with the sensitivity of 89.3% and specificity of 72.4%. Conclusions:Plasma PRL and Cor increase during syncope in VVS children, and plasma PRL is correlated with blood pressure drop.The increased plasma level of PRL in VVS children with positive HUT is correlated with blood pressure, and ΔCor is correlated with SBP.Plasma PRL and Cor may be involved in the pathogenesis of VVS and ΔPRL presents the diagnostic potential of VVS in children.