Nurse-recorded and ambulatory blood pressure predicts treatment-induced reduction of left ventricular hypertrophy equally well in hypertension: results from the Swedish irbesartan left ventricular hypertrophy investigation versus atenolol (SILVHIA) study

OBJECTIVE: To compare the relationships of treatment-induced reductions of left ventricular hypertrophy to the changes in clinic and ambulatory blood pressure (BP). DESIGN: Double-blind and randomized treatment with irbesartan or atenolol for 48 weeks. PATIENTS: Patients with hypertension and left ventricular hypertrophy (n = 66) with a seated diastolic BP 90-115 mmHg (average of three measurements one minute apart by nurses). MAIN OUTCOME MEASURES: Registrations of echocardiographic left ventricular (LV) mass. Clinic and ambulatory BP. RESULTS: In the total material, nurse-measured BP was reduced by 23 +/- 15/16 +/- 7.7 mmHg and 24-h ambulatory BP fell 20 +/- 15/14 +/- 8.5 mmHg by treatment. The correlation between the change in nurse-measured BP and LV mass index (LVMI) induced by treatment was r = 0.35, P = 0.004 for systolic BP and r = 0.26, P = 0.03 for diastolic BP. Corresponding values for 24-h ambulatory BP were r = 0.29, P = 0.02 and r = 0.35, P = 0.004, respectively, with similar correlations for day- and night-time ambulatory BP. The nurse-recorded BP was slightly higher than ambulatory BP (systolic clinic - systolic 24-h ambulatory BP = 5 mmHg). Using 130/80 mmHg as a cut-off value for normal 24-h ambulatory BP, eight subjects had normal diastolic or systolic ambulatory BP, or both. Interestingly, these patients also experienced LVMI regression following treatment (low/normal ABP, -13 +/- 21 g/m2; remaining patients, -18 +/- 22 g/m2, P > 0.5). CONCLUSIONS: In patients with hypertension and left ventricular hypertrophy, ambulatory BP is not superior to carefully standardized nurse-recorded seated BP in terms of associations with treatment-induced changes in LV mass.