Comparison of the 10-minute supine-30-minute tilt test with 24-hour ambulatory blood pressure for the diagnosis of diastolic systemic hypertension.

A variant of the protracted tilt test, the 10-minute supine -30-minute tilt test (10S-30TT), has been proposed by us for the evaluation of blood pressure (BP). The present investigation compares parameters of diastolic BP by 3 methods: office measurements, 10S-30TT, and 24-hour ambulatory monitoring; the last method served as a reference standard. Twenty patients presenting at the office with diastolic BP values ranging from 80 to 120 mm Hg (median 90) were studied. Statistically significant correlations were observed between the following parameters: diastolic office BP and average ambulatory awake diastolic BP (r = 0.64, p = 0.002); average tilt-test diastolic BP and average ambulatory awake diastolic BP (r = 0.69, p = 0.0006); frequency of elevated diastolic BP values during the tilt test and frequency of elevated ambulatory awake diastolic BP values (r = 0.69, p = 0.0007). Diastolic BP diagnosis scores exhibited strong correlation only between the ambulatory and tilt-test diagnosis (kappa = 0.70), but not between ambulatory and office BP diagnosis (kappa = 0.50). Based on the close correlation between results of the 10S-30TT and ambulatory monitoring in the evaluation of diastolic BP, we suggest that the faster and cheaper tilt test may serve as a substitute in certain categories of patients.