Predictive value of clinic and ambulatory heart rate for mortality in elderly subjects with systolic hypertension.

OBJECTIVE: To examine the association of clinic and ambulatory heart rate with total, cardiovascular, and noncardiovascular death in a cohort of elderly subjects with isolated systolic hypertension from the Systolic Hypertension in Europe Trial. METHODS: A total of 4682 patients participated, whose untreated blood pressure on conventional measurement at baseline was 160 to 219 mm Hg systolic and lower than 95 mm Hg diastolic. Clinic heart rate was the mean of 6 readings during 3 visits. Ambulatory heart rate was recorded with a portable intermittent technique in 807 subjects. RESULTS: Raised baseline clinic heart rate was positively associated with a worse prognosis for total, cardiovascular, and noncardiovascular mortality among the 2293 men and women taking placebo. Subjects with heart rates higher than 79 beats/min (bpm) (top quintile) had a 1.89 times greater risk of mortality than subjects with heart rate lower than or equal to 79 bpm (95% confidence interval, 1.33-2.68 bpm). In a Cox regression analysis, predictors of time to death were heart rate (P<.001), age (P<.001), serum creatinine level (P =.001), presence of diabetes (P =.002), previous cardiovascular disease (P =.01), triglyceride readings (P =.02), smoking (P =.04), and elevated systolic blood pressure (P =.05), while total cholesterol level was found to be nonsignificant in the model. In the ambulatory monitoring subgroup, clinic and ambulatory heart rates predicted noncardiovascular but not cardiovascular mortality. However, in a Cox regression analysis in which clinic and ambulatory heart rates were included, a significant association with noncardiovascular mortality was found only for clinic heart rate (P =.004). In the active treatment group, the weak predictive power of clinic heart rate for mortality disappeared after adjustment for confounders. CONCLUSIONS: In untreated older patients with isolated systolic hypertension, a clinic heart rate greater than 79 bpm was a significant predictor of all-cause, cardiovascular, and noncardiovascular mortality. Ambulatory heart rate did not add prognostic information to that provided by clinic heart rate.

Relationship between ambulatory blood pressure and follow-up clinic blood pressure in elderly patients with systolic hypertension.

BACKGROUND: Patients with elevated clinic blood pressure and normal ambulatory blood pressure have a better prognosis than patients with sustained ambulatory hypertension, and may not have to be treated with antihypertensive drugs. On the contrary, current guidelines emphasize repeated clinic blood pressure measurements for the initiation of antihypertensive therapy. OBJECTIVE: To examine the relationship between ambulatory blood pressure at baseline and clinic blood pressure after 6 months of follow-up in untreated hypertensive patients, and the relationships of these pressures with the subsequent incidence of cardiovascular events. METHODS: Patients who were > or = 60 years old, with systolic clinic blood pressure of 160-219 mmHg and diastolic pressure < 95 mmHg, participated in the Systolic Hypertension in Europe trial. The relationship between ambulatory blood pressure at baseline and clinic blood pressure after 6 months of follow-up was examined in 295 patients enrolled in the Ambulatory Blood Pressure Monitoring substudy and randomized to the placebo arm, and who were still on double-blind treatment and not taking other antihypertensive drugs after 6 months follow-up. RESULTS: Age averaged 70 +/- 6 years, 41% were men, and baseline daytime ambulatory blood pressure was 152 +/- 16/84 +/- 10 mmHg; clinic blood pressure decreased from 173 +/- 10/86 +/- 6 mmHg at baseline to 163 +/- 20/85 +/- 9 mmHg at month 6. Systolic daytime ambulatory blood pressure at baseline and systolic clinic blood pressure at month 6 were considered normal if < 140 mmHg. Of the 74 patients with normal systolic daytime ambulatory blood pressure at baseline, only seven (9.5%) had a normal systolic clinic blood pressure during follow-up. Conversely, of the 24 patients with normal follow-up clinic blood pressure, only seven (29%) had a normal systolic daytime ambulatory blood pressure at baseline. The incidence of cardiovascular events beyond the 6-month visit was significantly related to baseline ambulatory blood pressure but not to follow-up clinic pressure. CONCLUSIONS: Baseline daytime ambulatory blood pressure and follow-up clinic blood pressure do not identify the same patients for antihypertensive treatment. Baseline ambulatory pressure is a better predictor of cardiovascular events than follow-up clinic pressure.

Systolic blood pressure variability as a risk factor for stroke and cardiovascular mortality in the elderly hypertensive population.

OBJECTIVE: To investigate whether baseline systolic blood pressure variability was a risk factor for stroke, cardiovascular mortality or cardiac events during the Syst-Eur trial. DESIGN: The Syst-Eur study was a randomized, double-blind, placebo-controlled trial, powered to detect differences in stroke rate between participants on active antihypertensive treatment and placebo. Systolic blood pressure variability measurements were made on 744 participants at the start of the trial. Systolic blood pressure variability was calculated over three time frames: 24 h, daytime and night-time. The placebo and active treatment subgroups were analysed separately using an intention-to-treat principle, adjusting for confounding factors using a multiple Cox regression model. PARTICIPANTS: An elderly hypertensive European population. MAIN OUTCOME MEASURES: Stroke, cardiac events (fatal and non-fatal heart failure, fatal and non-fatal myocardial infarction and sudden death) and cardiovascular mortality (death attributed to stroke, heart failure, myocardial infarction, sudden death, pulmonary embolus, peripheral vascular disease and aortic dissection). RESULTS: The risk of stroke increased by 80% (95% confidence interval: 17-176%) for every 5 mmHg increase in night-time systolic blood pressure variability in the placebo group. Risk of cardiovascular mortality and cardiac events was not significantly altered. Daytime variability readings did not predict outcome. Antihypertensive treatment did not affect systolic blood pressure variability over the median 4.4-year follow-up. CONCLUSION: In the placebo group, but not the active treatment group, increased night-time systolic blood pressure variability on admission to the Syst-Eur trial was an independent risk factor for stroke during the trial.