Prognostic value of the variability in home-measured blood pressure and heart rate: the Finn-Home Study

Clinical significance of home blood pressure measurements for the prevention and management of high blood pressure

1. Ambulatory blood pressure (ABP) monitoring (M) provides BP information at many points on any particular day during unrestricted routine daily activities, whereas home blood pressure (HBP) monitoring provides a lot of BP information obtained under fixed times and conditions over a long period of time, thus mean values of HBP provide high reproducibility, and thus an overall superiority compared with ABP.  2. HBP is at least equally or better able than ABP to predict hypertensive target organ damage and prognosis of cardiovascular disease.  3. HBPM allows for ongoing disease monitoring by patients, improves adherence to antihypertensive treatment, and can provide health-care providers with timely clinical data and direct and immediate feedback regarding diagnosis and treatment of hypertension.  4. HBPM provides BP information in relation to time; that is, BP in the morning, in the evening and at night during sleep, and it is an essential tool for the diagnosis of white-coat and masked hypertension.  5. HBPM yields minimal alerting affects and no or minimal placebo effect, and can therefore distinguish small, but significant, serial changes in BP. It is thus the most practical method for monitoring BP in the day-to-day management of hypertension. 6. The superiority of HBPM over ABPM and clinic BPM is apparent from almost all practical and clinical research perspectives.

Blood pressure variability in risk stratification: What does it add?

1. In this minireview we address the predictive value of blood pressure variability, over and beyond level of pressure, in randomly selected population samples. All reviewed studies had sufficient power, long follow-up duration and a wide age range. 2. We assessed blood pressure variability derived from home visit, self-measured home pressure and 24 h ambulatory monitoring. The conclusions are based mainly on novel indices of blood pressure variability: variability independent of the mean, difference between maximum and minimum blood pressure and average real variability. 3. None of these variability indices or morning surge in blood pressure substantially refined risk profiling over and beyond the blood pressure level. 4. In risk stratification, clinicians should concentrate on blood pressure level, the predominant risk factor modifiable by lifestyle measures and antihypertensive drug treatment.

Arterial pressure and cerebral blood flow variability: friend or foe? A review

Variability in arterial pressure and cerebral blood flow has traditionally been interpreted as a marker of cardiovascular decompensation, and has been associated with negative clinical outcomes across varying time scales, from impending orthostatic syncope to an increased risk of stroke. Emerging evidence, however, suggests that increased hemodynamic variability may, in fact, be protective in the face of acute challenges to perfusion, including significant central hypovolemia and hypotension (including hemorrhage), and during cardiac bypass surgery. This review presents the dichotomous views on the role of hemodynamic variability on clinical outcome, including the physiological mechanisms underlying these patterns, and the potential impact of increased and decreased variability on cerebral perfusion and oxygenation. We suggest that reconciliation of these two apparently discrepant views may lie in the time scale of hemodynamic variability; short time scale variability appears to be cerebroprotective, while mid to longer term fluctuations are associated with primary and secondary end-organ dysfunction.

Day-to-day variability in home blood pressure is associated with cognitive decline: the Ohasama study

Although an association between high blood pressure and cognitive decline has been reported, no studies have investigated the association between home blood pressure and cognitive decline. Home blood pressure measurements can also provide day-to-day blood pressure variability calculated as the within-participant SD. The objectives of this prospective study were to clarify whether home blood pressure has a stronger predictive power for cognitive decline than conventional blood pressure and to compare the predictive power of the averaged home blood pressure with day-to-day home blood pressure variability for cognitive decline. Of 485 participants (mean age, 63 years) who did not have cognitive decline (defined as Mini-Mental State Examination score, <24) initially, 46 developed cognitive decline after a median follow-up of 7.8 years. Each 1-SD increase in the home systolic blood pressure value showed a significant association with cognitive decline (odds ratio, 1.48; P=0.03). However, conventional systolic blood pressure was not significantly associated with cognitive decline (odds ratio, 1.24; P=0.2). The day-to-day variability in systolic blood pressure was significantly associated with cognitive decline after including home systolic blood pressure in the same model (odds ratio, 1.51; P=0.02), whereas the odds ratio of home systolic blood pressure remained positive, but it was not significant. Home blood pressure measurements can be useful for predicting future cognitive decline because they can provide information not only on blood pressure values but also on day-to-day blood pressure variability.

Blood pressure variability assessed by home measurements: a systematic review

Accumulating evidence suggests that day-by-day blood pressure (BP) variability assessed using self-measurements by patients at home (HBPV) provides useful information beyond that of average home BP. This systematic review summarizes the current evidence on day-by-day HBPV. A systematic literature search (PubMed) revealed 22 eligible articles. Independent prognostic value of day-by-day HBPV for cardiovascular events and total mortality was demonstrated in two outcome studies, whereas novel indices of variability had minimal or no independent prognostic ability. Although findings are not consistent among the studies, the evidence suggests that HBPV has an independent role in the progression of preclinical cardiac, arterial and renal damage and is affected by age, gender, average BP and heart rate level, antihypertensive treatment, antihypertensive drug class and other factors. However, there is large diversity among the available studies in the home BP monitoring protocols, the indices used to quantify HBPV and the end points selected for evaluation. Overall, these preliminary data largely based on heterogeneous studies indicate an important and independent role of day-by-day HBPV in the pathogenesis of hypertension-induced cardiovascular damage. Yet, fundamental questions remain unanswered, including the optimal variability index, the optimal home monitoring schedule required, the threshold that defines increased HBPV and the impact of treatment-induced variability change on organ damage and cardiovascular events. Until these questions are adequately addressed in future studies, HBPV should largely remain a research issue with limited practical value for individual patients.

Physiological correlates of beat-to-beat, ambulatory, and day-to-day home blood pressure variability after transient ischemic attack or minor stroke

BACKGROUND AND PURPOSE

Visit-to-visit and day-to-day variability in systolic blood pressure (SBP) are associated with an increased risk of stroke, more strongly than variability on 24-hour ambulatory BP monitoring, but underlying physiological mechanisms are unclear. We related potentially relevant physiological characteristics to beat-to-beat, ambulatory, and day-to-day BP variability to identify underlying mechanisms and potential therapeutic targets.

METHODS

BP variability (coefficient of variation [CV]) on 1-month home BP monitoring (3 sitting readings, 3× daily), on 24-hour ambulatory BP monitoring, and on 5-minute beat-to-beat monitoring was related to BP reactivity (to mental arithmetic), arterial aging (aortic stiffness: carotid-femoral pulse wave velocity; aortic pulsatility), heart rate variability (CV of normal-to-normal R-R interval), and orthostatic responses.

RESULTS

In 223 patients within 6 weeks of a transient ischemic attack or minor stroke, beat-to-beat and home SBP-CVs were associated with response to arithmetic (beat-to-beat odds ratio per SD=1.64; P<0.0001 and home BP monitoring, 1.41; P=0.025), aortic stiffness (1.84; P<0.0001 and 1.31; P=0.04), aortic pulsatility (1.98; P<0.0001 and 1.61; P<0.0001), and heart rate variability-CV of normal-to-normal R-R interval (1.34; P=0.03 and 1.35; P=0.03), independently of age, sex, and aortic BP. Orthostatic BP changes were associated only with SBP-CV on home BP monitoring (0.62; P=0.002). In contrast, no physiological measures were associated with within-day BP variability on awake ambulatory BP monitoring except response to mental arithmetic (1.40; P=0.01).

CONCLUSIONS

Beat-to-beat and day-to-day SBP variability, but not variability on ambulatory BP monitoring, had similar physiological correlates, suggesting common underlying mechanisms and identifying potentially treatable targets that may be responsible for the relationship between SBP variability and stroke risk.

Blood pressure variability and cerebrovascular disease

Variability is an aspect of blood pressure (BP) relatively unknown and poorly evaluated systematically in clinical practice. Although the introduction of intensive BP measurement methods, such as ambulatory blood pressure monitoring provided evidence of the importance of BP variability in the short-term, more recently, however, emphasis has been placed on the relevance of variability of BP in the medium- and long-term. The adverse cardiovascular consequences of high BP not only depend on absolute BP values, but also on BP variability. Independently of mean BP levels, BP variations in the short- and long-term are associated an increased risk of cardiovascular events and mortality. Also, it has been suggested that modulation of such variability may explain the different level protection exerted by different antihypertensive-drug classes.

Comparative effects of telmisartan and valsartan as add-on agents for hypertensive patients with morning blood pressure insufficiently controlled by amlodipine monotherapy

The aim of this study was to determine the efficacies of valsartan and telmisartan as add-on agents for the control of morning blood pressure (BP) in patients already on amlodipine monotherapy. A total of 414 hypertensive patients were prospectively enrolled in a 4-week run-in period when they were treated with amlodipine (5 mg/day), and home BP was measured in the morning and evening. Patients with home systolic BP (SBP) being 135-159 mm Hg in the morning at the end of the run-in period were randomized to additional treatment with valsartan (80 mg/day) or with telmisartan (40 mg/day) for 8 weeks. The primary endpoint was the change in morning home BP, and secondary endpoints included variability of morning home BP. Of the 282 patients randomized, 262 patients (n=131, in each treatment) completed the protocols. Demographic parameters and baseline morning SBP/diastolic BP (DBP) (146.3±7.1/84.8±9.3 vs. 146.0±7.1/84.2±9.1 mm Hg) were comparable in the valsartan group and telmisartan group, and changes in SBP/DBP after 8-week treatment were not significantly different between the two groups (-7.4±10.6/-3.9±6.1 vs. -8.3±9.9/-5.0±5.9 mm Hg). Valsartan significantly increased individual standard deviation and variation coefficient of morning SBP, but telmisartan did not change either of these indices of SBP variation. In subgroups with baseline SBP being above the median (145.2 mm Hg), change in DBP was significantly larger by telmisartan than by valsartan (-6.3±5.6 vs. -3.9±6.7 mm Hg, P<0.05). These results suggest that telmisartan is more useful than valsartan as an add-on agent for reducing the level and variability of morning BP in patients on amlodipine monotherapy.

Blood Pressure Variability: Prognostic Value and Therapeutic Implications

Blood pressure variability (BPV) is considered nowadays a novel risk factor for cardiovascular disease. Early findings in sinoaortic denervated rats have clearly shown that enhanced fluctuation of blood pressure induced left ventricular hypertrophy, vascular stiffness, and renal lesion. A large number of clinical trials confirm that short-term and long-term blood pressure variability independently contributes to target organ damage, cardiovascular events, and mortality not only in hypertensive patients but also in subjects with diabetes mellitus and chronic kidney disease. Therefore, amelioration of BPV has been suggested as an additional target of the treatment of cardiovascular diseases. Preliminary evidence obtained from meta-analysis and controlled clinical trials has shown that antihypertensive classes differ in their ability to control excessive BP fluctuations with an impact in the prevention of cardiovascular events. Calcium channel blockers seem to be more effective than other blood pressure lowering drugs for the reduction of short-term and long-term BPV. In order to increase actual knowledge regarding the prognostic value and therapeutic significance of BPV in cardiovascular disease, there is a need for additional clinical studies specifically designed for the study of the relevance of short-term and long-term BPV control by antihypertensive drugs.

Diagnostic tools for hypertension and salt sensitivity testing

PURPOSE OF REVIEW

One-third of the world's population has hypertension and it is responsible for almost 50% of deaths from stroke or coronary heart disease. These statistics do not distinguish salt-sensitive from salt-resistant hypertension or include normotensives who are salt-sensitive even though salt sensitivity, independent of blood pressure, is a risk factor for cardiovascular and other diseases, including cancer. This review describes new personalized diagnostic tools for salt sensitivity.

RECENT FINDINGS

The relationship between salt intake and cardiovascular risk is not linear, but rather fits a J-shaped curve relationship. Thus, a low-salt diet may not be beneficial to everyone and may paradoxically increase blood pressure in some individuals. Current surrogate markers of salt sensitivity are not adequately sensitive or specific. Tests in the urine that could be surrogate markers of salt sensitivity with a quick turn-around time include renal proximal tubule cells, exosomes, and microRNA shed in the urine.

SUMMARY

Accurate testing of salt sensitivity is not only laborious but also expensive, and with low patient compliance. Patients who have normal blood pressure but are salt-sensitive cannot be diagnosed in an office setting and there are no laboratory tests for salt sensitivity. Urinary surrogate markers for salt sensitivity are being developed.

Assessment and interpretation of blood pressure variability in a clinical setting

Blood pressure (BP) is characterized by marked fluctuations occurring within the 24 h as a result of complex interactions between behavioral, environmental, humoral, and neural central or reflex influences. Significant BP variations also occur over more prolonged periods of time (i.e. between days, weeks, months, seasons and even years), not as a random phenomenon but as a result of several interacting factors yet not completely identified. Depending on the method and time interval considered for measurement, the clinical significance and prognostic implications of different types of BP variability (BPV) may substantially differ. Either in the short or in the long term, BPV has been associated with development, progression and severity of cardiac, vascular and renal organ damage and with an increased risk of cardiovascular events and mortality, independently adding to cardiovascular risk, over and above the contribution of elevated mean BP levels. The present paper provides a review on the main methods currently employed for assessment of BPV as well as on the mechanisms, clinical interpretation and prognostic significance of different types of BPV, addressing the question on whether BPV should be a target for antihypertensive treatment for the current prevention of cardiovascular disease.

Favorable effects of carotid endarterectomy on baroreflex sensitivity and cardiovascular neural modulation: a 4-month follow-up

Carotid surgery variably modifies carotid afferent innervation, thus affecting arterial baroreceptor sensitivity. Low arterial baroreflex sensitivity is a well-known independent risk factor for cardiovascular diseases. The aim of this study was to assess the 4-mo effects of carotid endarterectomy (CEA) on arterial baroreceptor sensitivity and cardiovascular autonomic profile in patients with unilateral carotid stenosis. We enrolled 20 patients (72 ± 8 yr) with unilateral >70% carotid stenosis. ECG, beat-by-beat blood pressure, and respiration were continuously recorded before and 126 ± 9 days after CEA, at rest and during a 75° head-up tilt. Both pharmacological (modified Oxford technique, BRS) and spontaneous (index α, spectral analysis) arterial baroreflex sensitivity were assessed. Cardiovascular autonomic profile was evaluated by plasma catecholamines and spectral indexes of cardiac sympathovagal modulation [low-frequency R-R interval (LFRR), low frequency-to high frequency ratio (LF/HF), high-frequency R-R interval (HFRR)] and sympathetic vasomotor control [low-frequency systolic arterial pressure (LFSAP)] obtained from heart rate and SAP variability. After CEA, both the index α and BRS were higher (P < 0.02) at rest. SAP variance decreased both at rest and during tilt (P < 0.02). Before surgery, tilt did not modify the autonomic profile compared with baseline. After CEA, tilt increased LF/HF and LFSAP and reduced HFRR compared with rest (P < 0.02). Four months after CEA was performed, arterial baroreflex sensitivity was enhanced. Accordingly, the patients' autonomic profile had shifted toward reduced cardiac and vascular sympathetic activation and enhanced cardiac vagal activity. The capability to increase cardiovascular sympathetic activation in response to orthostasis was restored. Baroreceptor sensitivity improvement might play an additional role in the more favorable outcome observed in patients after carotid surgery.

Blood pressure variability in elderly persons with white-coat and masked hypertension compared to those with normotension and sustained hypertension

BACKGROUND

The relationship between blood pressure (BP) measured, its variability, and risk of cardiovascular events is well established; however, it is not well known whether there is a difference of variability between the four categories of BP status obtained by the comparison of office and home BP measurements: normotension and masked, white-coat, and sustained hypertension. Here, we assessed BP variability (BPV) according to BP status in the elderly.

METHODS

The study population consisted of 1,701 individuals aged ≥73 years drawn from the general population. Office and home BP measurements were obtained with the same device. At home, 18 measures were taken (3 in the morning, 3 in the evening, for 3 consecutive days). BP statuses were defined according to European Society of Hypertension recommendations. To assess BPV, seven indexes were defined (e.g., standard deviation of the 18 measures, day-to-day variability, triplet-to-triplet variability, and coefficient of variation).

RESULTS

Subjects with white-coat hypertension and normotension had similar BPV, and the variability among those with masked hypertension was very close to that in those with sustained hypertension. Overall, BPV was much higher in subjects with masked hypertension than in those with white-coat hypertension, in both treated and untreated groups.

CONCLUSIONS

In elderly individuals, the short-term variability of BP is similar in masked and sustained hypertension and higher than in normotension and white-coat hypertension. This result suggests the hypothesis that BPV among persons with masked hypertension may contribute to the elevated cardiovascular risk observed in this BP pattern.

Assessment and management of blood-pressure variability

Blood pressure (BP) is characterized by marked short-term fluctuations occurring within a 24 h period (beat-to-beat, minute-to-minute, hour-to-hour, and day-to-night changes) and also by long-term fluctuations occurring over more-prolonged periods of time (days, weeks, months, seasons, and even years). Rather than representing 'background noise' or a randomly occurring phenomenon, these variations have been shown to be the result of complex interactions between extrinsic environmental and behavioural factors and intrinsic cardiovascular regulatory mechanisms. Although the adverse cardiovascular consequences of hypertension largely depend on absolute BP values, evidence from observational studies and post-hoc analyses of data from clinical trials have indicated that these outcomes might also depend on increased BP variability (BPV). Increased short-term and long-term BPV are associated with the development, progression, and severity of cardiac, vascular, and renal damage and with an increased risk of cardiovascular events and mortality. Of particular interest are the findings from post-hoc analyses of large intervention trials in hypertension, showing that within-patient visit-to-visit BPV is strongly prognostic for cardiovascular morbidity and mortality. This result has prompted discussion on whether antihypertensive treatment should be targeted not only towards reducing mean BP levels but also to stabilizing BPV with the aim of achieving consistent BP control over time, which might favour cardiovascular protection.

Rationale, study design, baseline characteristics and blood pressure at 16 weeks in the HONEST Study

On the basis of the studies that investigated the relationship between baseline clinic blood pressure (CBP) or home blood pressure (HBP) values and cardiovascular (CV) events, HBP has been reported to have a stronger prognostic ability. However, few studies have compared the prognostic ability of on-treatment CBP and HBP. The relationship between on-treatment HBP, measured twice in the morning and twice at bedtime, and CV events was investigated in over 20 000 patients in the HONEST (Home blood pressure measurement with Olmesartan Naive patients to Establish Standard Target blood pressure) Study, a prospective, 2-year observational study of treatment with an angiotensin receptor blocker, olmesartan (OLM), in OLM-naive hypertensive patients. This report summarizes the study protocol, the baseline characteristics of the patients and CBP and HBP at 16 weeks. A total of 22 373 patients were registered across Japan; baseline data from 22 162 patients were collected. Baseline HBP (mean±s.d.) in the morning (the first measurement) was 151.6±16.4/87.1±11.8 mm Hg and at bedtime was 144.3±16.8/82.8±11.9 mm Hg, whereas CBP was 153.6±19.0/87.1±13.4 mm Hg. At 16 weeks, morning HBP was 135.0±13.7/78.8±9.9 mm Hg and bedtime HBP was 129.7±13.8/74.7±10.1 mm Hg, whereas CBP was 135.6±15.4/77.6±10.9 mm Hg. The follow-up period for each patient ends on 30 September 2012. The HONEST Study is expected to provide evidence showing the relationship between baseline and on-treatment CBP and HBP levels (both first and second measurements) and CV events.

Blood pressure variability, cardiovascular risk, and risk for renal disease progression

The adverse cardiovascular consequences of high blood pressure (BP) not only depend on absolute BP values, but also on BP variability (BPV). Evidence has been provided that independently of mean BP levels, BP variations in the short- and long-term are associated with the development, progression and severity of cardiac, vascular and renal organ damage, and with an increased risk of CV events and mortality. Alterations in BPV have also been shown to be predictive of the development and progression of renal damage, which is of relevance if considering that impaired renal function in a hypertensive patient constitutes a very potent predictor of future CV events and mortality even in treated subjects. This review will address whether antihypertensive treatment should target alterations in BPV, in addition to reducing absolute BP levels, in order to achieve the highest CV and renal protection in hypertensive and renal patients.

Home blood pressure variability as cardiovascular risk factor in the population of Ohasama

Blood pressure variability based on office measurement predicts outcome in selected patients. We explored whether novel indices of blood pressure variability derived from the self-measured home blood pressure predicted outcome in a general population. We monitored mortality and stroke in 2421 Ohasama residents (Iwate Prefecture, Japan). At enrollment (1988-1995), participants (mean age, 58.6 years; 60.9% women; 27.1% treated) measured their blood pressure at home, using an oscillometric device. In multivariable-adjusted Cox models, we assessed the independent predictive value of the within-subject mean systolic blood pressure (SBP) and corresponding variability as estimated by variability independent of the mean, difference between maximum and minimum blood pressure, and average real variability. Over 12.0 years (median), 412 participants died, 139 of cardiovascular causes, and 223 had a stroke. In models including morning SBP, variability independent of the mean and average real variability (median, 26 readings) predicted total and cardiovascular mortality in all of the participants (P≤0.044); variability independent of the mean predicted cardiovascular mortality in treated (P=0.014) but not in untreated (P=0.23) participants; and morning maximum and minimum blood pressure did not predict any end point (P≥0.085). In models already including evening SBP, only variability independent of the mean predicted cardiovascular mortality in all and in untreated participants (P≤0.046). The R(2) statistics, a measure for the incremental risk explained by adding blood pressure variability to models already including SBP and covariables, ranged from <0.01% to 0.88%. In a general population, new indices of blood pressure variability derived from home blood pressure did not incrementally predict outcome over and beyond mean SBP.

The International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO): moving from baseline characteristics to research perspectives

The objective of this study is to construct an International Database of HOme blood pressure in relation to Cardiovascular Outcome (IDHOCO). The main goal of this database is to determine outcome-based diagnostic thresholds for the self-measured home blood pressure (BP). Secondary objectives include investigating the predictive value of white-coat and masked hypertension, morning and evening BP, BP and heart rate variability, and the home arterial stiffness index. We also aim to determine an optimal schedule for home BP measurements that provides the most accurate risk stratification. Eligible studies are population-based, have fatal as well as nonfatal outcomes available for analysis, comply with ethical standards, and have been previously published in peer-reviewed journals. In a meta-analysis based on individual subject data, composite and cause-specific cardiovascular events will be related to various indexes derived by home BP measurement. The analyses will be stratified by a cohort and adjusted for the clinic BP and established cardiovascular risk factors. The database includes 6753 subjects from five cohorts recruited in Ohasama, Japan (n=2777); Finland (n=2075); Tsurugaya, Japan (n=836); Didima, Greece (n=665); and Montevideo, Uruguay (n=400). In these five cohorts, during a total of 62 106 person-years of follow-up (mean 9.2 years), 852 subjects died and 740 participants experienced a fatal or nonfatal cardiovascular event. IDHOCO provides a unique opportunity to investigate several hypotheses that could not reliably be studied in individual studies. The results of these analyses should be of help to clinicians involved in the management of patients with suspected or established hypertension.

Home blood pressure variability on one occasion is a novel factor associated with arterial stiffness in patients with type 2 diabetes

Recent studies have suggested that not only mean blood pressure but also variability in blood pressure might be related to cardiovascular disease. The aim of this study was to investigate the association between home blood pressure variability on one occasion and markers of arterial stiffness in patients with type 2 diabetes. We investigated the relationship between the s.d. of clinic- or home-measured systolic blood pressure on one occasion and pulse wave velocity (PWV) in 332 patients with type 2 diabetes, and we evaluated whether the SD of clinic- or home-measured systolic blood pressure on one occasion was an independent determinant of PWV by multivariate linear regression analysis, after adjustment for known risk factors for arterial stiffness, including sex, age, duration of diabetes, body mass index, hemoglobin A1c, serum total cholesterol, triglycerides, smoking status, drinking alcohol, presence of antihypertensive medication, average systolic blood pressure and heart rate. Age, average morning home-measured systolic blood pressure, heart rate and PWV (r=0.259, P<0.0001) were positively correlated with the s.d. of morning home blood pressure on one occasion. Multiple regression analysis demonstrated that age, average morning home-measured systolic blood pressure (P=0.0019), heart rate and the s.d. of morning home-measured systolic blood pressure on one occasion (P=0.0159) were independently associated with PWV. In conclusion, home blood pressure variability on one occasion was correlated with PWV, independent of other known risk factors, in Japanese patients with type 2 diabetes.

Within-subject blood pressure level--not variability--predicts fatal and nonfatal outcomes in a general population

To assess the prognostic significance of blood pressure (BP) variability, we followed health outcomes in a family-based random population sample representative of the general population (n=2944; mean age: 44.9 years; 50.7% women). At baseline, BP was measured 5 times consecutively at each of 2 home visits 2 to 4 weeks apart. We assessed within-subject overall (10 readings), within- and between-visit systolic BP variability from variability independent of the mean, the difference between maximum and minimum BP, and average real variability. Over a median follow-up of 12 years, 401 deaths occurred and 311 participants experienced a fatal or nonfatal cardiovascular event. Overall systolic BP variability averaged (SD) 5.45 (2.82) units, 15.87 (8.36) mmHg, and 4.08 (2.05) mmHg for variability independent of the mean, difference between maximum and minimum BP, and average real variability, respectively. Female sex, older age, higher-mean systolic BP, lower body mass index, a history of peripheral arterial disease, and use of β-blockers were the main correlates of systolic BP variability. In multivariable-adjusted analyses, overall and within- and between-visit BP variability did not predict total or cardiovascular mortality or the composite of any fatal plus nonfatal cardiovascular end point. For instance, the hazard ratios for all cardiovascular events combined in relation to overall variability independent of the mean, difference between maximum and minimum BP, and average real variability were 1.05 (0.96-1.15), 1.06 (0.96-1.16), and 1.08 (0.98-1.19), respectively. By contrast, mean systolic BP was a significant predictor of all end points under study, independent of BP variability. In conclusion, in an unbiased population sample, BP variability did not contribute to risk stratification over and beyond mean systolic BP.