Blood pressure control in a hypertension hospital clinic

Abstract

Objectives: First, to evaluate the prevalence of clinic blood pressure (BP) control (BP < or = 140/90 mm Hg) in a representative sample of treated hypertensive patients followed in our hypertension clinic. Second, to assess in a subgroup of these patients: (a) the proportion of BP control with both clinic blood pressure (CBP < or =140/90 mm Hg) and daytime ambulatory blood pressure (ABP) (< or =132/85 mm Hg) criteria, and (b) the prevalence of echocardiographic left ventricular hypertrophy (LVH) (left ventricular mass index, LVMI>125 g/m2 in men and >110 g/m2 in women).

Design and methods: Seven hundred consecutive hypertensive patients who attended our hypertension centre clinic during a period of 6 months and who had regularly been followed up by the same medical team were included in the study. BP was taken in the clinic by a doctor using a mercury sphygmomanometer with the participants seated. Seventy-four patients with similar demographic and clinical characteristics to the entire population of participants underwent complete echocardiographic examination and 24 h ABP monitoring.

Results: During follow-up, 352 of the treated patients had clinic BP < or =140/90 mm Hg, 198< or =160/95 mm Hg and 150>160/95 mm Hg, indicating that BP control was satisfactory in 50.3%, borderline in 28.3% and unsatisfactory in 21.4% of the cases. In the subgroup of 74 patients, the proportion of individuals with satisfactory clinic BP control (CBP< or =140/90 mm Hg) was higher (50.0 versus 33.6%) than with satisfactory ABP control (daytime ABP values < or =132/85 mm Hg). LVH was found in 21 of the 74 patients (28.3%): 12 of them had unsatisfactory CBP control and 19 had unsatisfactory ABP control. LVMI did not correlate with CBP values but only with ABP values (mean 24 h systolic r = 0.47, diastolic r = 0.40, P<0.001; mean daytime systolic r = 0.45, mean daytime diastolic r = 0.39, P<0.001; mean night-time systolic r = 0.38, mean night-time diastolic r = 0.38, P<0.001).

Conclusion: This study demonstrates that hypertensive patients managed in a hypertension centre clinic have satisfactory CBP control in 50% of cases, but this rate seems to over-estimate the effective BP control during daily life. A large fraction of patients show persistence of LVH and this evidence of organ damage almost entirely concerns individuals with poor ABP control.