Related factors of head up tilt test in children with vasovagal syncope

Objective To summarize the risk factors of head up tilt test (HUTT) in children with vasovagal syncope,and provide theoretical reference for the diagnosis of vasovagal syncope.Methods The total of 340 children with headache and syncope were included in the study,all the cases received HUTT,including basic tilt table test and sublingual nitroglycerin test.And they were divided into HUTT positive group and HUTT negative group according to the results.The clinical information of two groups was analyzed by multivariate Logistic regression to summarize risk factors.Results The frequency of syncope in HUTT positive group was 2.3 ± 1.1,significantly higher than that in HUTT negative group (0.7 ±0.2),chest tightness and blurred vision ratios were significandy higher than those in HUTT negative group (84/186,48/186 vs.34/154,23/154).Single factor analysis showed,older than 12 years old,female,blurred vision,with history and genetic history of syncope,numerous of syncope,chest tightness,fatigue were related factors as positive results for HUTT.Multivariate Logistic regression analysis showed,older than 12 years old,female,with history and genetic history of syncope were independent risk factors of positive HUTF.β was 0.744,1.126,1.312,0.514 respectively,95％ CI was 1.132-5.968,1.985-5.040,1.366-9.677,1.683-6.532 respectively.Conclusion Age,gender,family history,history of syncope have important significance to predict HUTT results. Key words: Syncope,vasovagal;  Risk factors;  Head up tilt test