Blood pressure variability in controlled and uncontrolled blood pressure and its association with left ventricular hypertrophy and diastolic function

摘要

High systolic blood pressure (SBP) variability has been associated with higher risk for target-organ damage. In a cross-sectional study done in a tertiary outpatient hypertension clinic, we compared short-term SBP variability among controlled and uncontrolled hypertensive patients and evaluated the association between higher levels of SBP variability and diastolic function and left ventricular hypertrophy (LVH). Patients were evaluated by 24-h ambulatory blood pressure monitoring and transthoracic Doppler echocardiogram. Blood pressure (BP) variability was evaluated by the time-rate index and high variability corresponded to index values in the top quartile of distribution. Echocardiographic parameters were compared in patients with and without higher BP variability within controlled and uncontrolled office BP (<= 140/90 mm Hg). The analyses included 447 patients with 58 +/- 12 years of age, 67% were women, 68% white, 43% current or previous smokers and 32% with diabetes mellitus. Among the whole sample, 137 patients had controlled and 310 uncontrolled BP. The 75th percentile cutoff points for the time-rate index were 0.502 mm Hg min(-1) and 0.576 mm Hg min(-1) for participants with controlled and uncontrolled BP, respectively. After adjustment for confounders, the time-rate index did not differ between controlled and uncontrolled patients. BP variability was not associated with LVH or diastolic function in controlled and uncontrolled BP after adjustment for 24-h SBP and age. Patients with controlled and uncontrolled BP had similar SBP variability assessed by time-rate index, which was not associated with LVH or diastolic function. These findings should be confirmed in studies with larger sample size.