Objective:To explore differences in the detection rate of elevated blood pressure (BP) in children aged 6-8 years old, and to verify the apparent existence of white-coat hypertension (BP) in children.

Methods:Based on census data(PROC), and three subsequent BP readings were taken during follow-ups which were carried out from October 2018 to June 2019. A total of 1 785 children were included in the present study. Using updating blood pressure reference for Chinese children aged 3-17 years, compared the BP detection rate at baseline, at the first follow-up, and the average value of the last two BP readings. Fluctuations in the detection rate of elevated BP in children at different time-points were analyzed.

Results:The detection rates of the three elevated BP measurements of 6-8-year-old children were 57.65%, 25.88% and 15.46%, respectively, and the detection rate was higher among boys than girls. The detection rate of baseline BP was higher than that of the first follow-up BP measurements and the average of the last two BP measurements(P<0.01). Given the agreement in the diagnosis of high SBP, high DBP, high BP at baseline, and the average of the last two follow-up BP measurements, elevated BP at baseline was the lowest among the three groups and SBP was higher than DBP.

Conclusion:Blood Pressure fluctuations might be caused by transient tension that was experienced during the baseline BP measurement and during the first of the three follow-ups. Therefore, the average value of last two BP measurements may better reflect the real BP level in children.