Objective: To determine the longitudinal relationship between clinic and ambulatory blood pressures and subsequent left ventricular and carotid artery structure.
Design: A retrospective follow-up study.
Setting: A large district general hospital in Harrow, UK.
Patients: One hundred and forty patients who had been subjected to 24 h ambulatory intra-arterial blood pressure monitoring on the basis of their having an elevated clinic blood pressure were followed up randomly a mean of 9.4 +/- 3.4 years later. The ambulatory blood pressure parameters measured were the mean systolic, mean diastolic and mean pulse pressures. Follow-up variables assessed included the clinic blood pressure, body mass index, total cholesterol, number of years of follow-up, left ventricular mass index, carotid intima-media thickness and carotid artery cross-sectional area.
Main outcome measures: The left ventricular mass index, carotid intima-media thickness and carotid artery cross-sectional area.
Results: The mean pulse pressure and mean systolic blood pressure were correlated significantly with the left ventricular mass index (r = 0.46, P < 0.001 and r = 0.36, P < 0.001, respectively), carotid intima-media thickness (r = 0.45, P < 0.001 and r = 0.37, P < 0.001, respectively) and carotid artery cross-sectional area (r = 0.46, P < 0.001 and r = 0.41, P < 0.001, respectively). The mean pulse pressure was associated independently with all three outcome measures. In addition, the body mass index was an independent determinant of the left ventricular mass index, whereas the serum cholesterol level was associated independently with the carotid artery cross-sectional area; the number of years of follow-up was related independently to the left ventricular mass index and carotid intima-media thickness, but not to the cross-sectional area.
Conclusions: These findings suggest that ambulatory blood pressure monitoring can play a role in guiding the choice of doses in drug therapy to limit potential target organ damage.