'White coat' hypertension in children.

BACKGROUND: Research with ambulatory blood pressure monitoring (ABPM) clearly demonstrates the importance of identifying "white coat" hypertension before making the diagnosis of hypertension. While the existence of white coat hypertension has been documented in adults, it is unknown whether this phenomenon is present during childhood. Therefore, the purposes of this study were to determine whether white coat hypertension exists in children with a positive family history of essential hypertension; and if it exists, to compare 24-hour ambulatory blood pressure patterns among normotensive, white coat hypertensive, and hypertensive children.

METHODS: One hundred fifty-nine children (aged 5 to 15 years) participated in the study. Based on office systolic and diastolic measurements and 24-hour ABPM, subjects were placed into one of three groups: normotensive, white coat hypertensive, and hypertensive.

RESULTS: Forty-four percent of 34 subjects with systolic blood pressures greater than or equal to 95th percentile were reclassified as white coat hypertensive; 56% remained hypertensive. Group comparisons of 24-hour ABPM patterns showed significant differences between groups. Also, the ABPM patterns of white coat hypertensive patients were significantly different from those of normotensive patients.

CONCLUSIONS: This study documented the existence of white coat hypertension in children and showed that white coat hypertensive children were significantly different from normotensive and hypertensive children on most comparisons of 24-hour ABPM data. Also, when age and sex were controlled, heavier children had a more significant chance of having elevated systolic blood pressure than normal-weight children, regardless of their race, height, or body mass index.