OBJECTIVE
Since younger patients have low pretest probability of hypertension and are susceptible to reactive and masked hypertension, ambulatory blood pressure monitoring can be useful. To better target use in referred patients, we sought to define in-clinic systolic blood pressure measures that predicted normal ambulatory blood pressure monitoring and target end organ damage.
DESIGN,SETTING,PATIENTS,OUTCOME MEASURES
Data were collected on consecutive patients referred for high blood pressure undergoing an ambulatory blood pressure monitor from 2010–13 (n=248, 33.9% female, mean age 15.5 ± 3.6 years). Candidate in-clinic predictors were systolic maximum, minimum or average blood pressures obtained by auscultative, oscillometric or both. Multivariable logistic regression models were used to determine the prediction of normal ambulatory blood pressure monitoring by in-clinic blood pressure predictors. Separate models considered predicting left ventricular hypertrophy by in-clinic systolic blood pressure versus ambulatory blood pressure monitoring-defined hypertension. Identified predictor utility was tested with receiver operator characteristic curves.
RESULTS
Maximum (OR 0.97 [95%CI 0.94–0.99]; p=0.047), minimum (0.96 [0.94–0.99]; p=0.002) and average (0.97 [0.95–1.00]; p=0.04) in-clinic auscultative systolic blood pressure predicted normal ambulatory blood pressure monitoring. Each had a cstatistic of 0.58. Left ventricular hypertrophy was associated with in-clinic auscultative minimum systolic blood pressure treated continuously (1.05, [1.01 – 1.10], p=0.01) or dichotomized at the 90th percentile (8.23, [1.48 – 45.80], p=0.02), as well as ambulatory blood pressure monitoring-defined hypertension (3.31, [1.23 – 8.91], p = 0.02). Both predictors had poor sensitivity and specificity.
CONCLUSION
In youth, normal auscultative in-clinic systolic blood pressure indices weakly predicted normal ambulatory blood pressure and target end organ damage.