Version July 2025
INTRODUCTION —
In terms of population-attributable risk, hypertension is the most important modifiable risk factor for premature cardiovascular disease [1]; it is more common than cigarette smoking, dyslipidemia, and diabetes, which are the other major risk factors (table 1). Hypertension accounts for an estimated 54 percent of all strokes and 47 percent of all ischemic heart disease events globally [2]. (See "Overview of established risk factors for cardiovascular disease".)
The impact of hypertension on the risk for cardiovascular disorders and the impact of cardiovascular risk on therapeutic decisions in the treatment of hypertension are discussed in this topic. The effects of different antihypertensive drugs and of different blood pressure goals on cardiovascular outcomes are presented elsewhere:
●(See "Hypertension in adults: Initial drug therapy".)
●(See "Goal blood pressure in adults with hypertension".)
IMPACT OF HYPERTENSION ON CARDIOVASCULAR DISEASE —
Hypertension increases the risk for a variety of cardiovascular diseases [3-5], including stroke, coronary artery disease, heart failure, atrial fibrillation [6], abdominal aortic aneurysm, and peripheral vascular disease. In a large electronic medical record cohort of 1.25 million patients, those with hypertension had a higher lifetime risk of cardiovascular disease than those without high blood pressure (63 versus 46 percent) and, on average, developed cardiovascular disease five years earlier [4].
The risk for both coronary disease and stroke increases progressively with incremental increases in blood pressure above 115/75 mmHg, as shown in numerous epidemiologic studies (figure 1A-B) [7-13]. For each 20/10 mmHg increase in systolic/diastolic blood pressure, there is a doubling of coronary heart- and stroke-related mortality. However, these observations do not prove a causal relationship, since increasing blood pressure could be a marker for other risk factors such as increasing body weight, which is associated with dyslipidemia, glucose intolerance, and the metabolic syndrome. The best evidence for a causal role of increasing blood pressure in cardiovascular complications is an improvement in outcome as blood pressure is reduced with antihypertensive therapy [14]. (See "Goal blood pressure in adults with hypertension".)
The increase in cardiovascular risk has primarily been described in terms of elevated systolic pressure in older adults [15] and elevation in both systolic and diastolic pressure in younger individuals. Pulse pressure, which is the difference between the systolic and diastolic blood pressures and is determined primarily by large artery stiffness, is also a strong predictor of risk, particularly in older individuals [15]. Conversely, isolated diastolic hypertension, in which the diastolic pressure is elevated but the systolic pressure is normal, is uncommon in the adult and not associated with a higher cardiovascular risk [16]. (See "Increased pulse pressure".)
Out-of-office blood pressure measurements may predict cardiovascular risk better than routine clinic measurements, a fact that has led to increased reliance upon home and ambulatory blood pressure monitoring (ABPM) to make the diagnosis of hypertension [5,17]. These issues are presented elsewhere:
●(See "Overview of hypertension in adults", section on 'Making the diagnosis of hypertension'.)
●(See "Hypertension in adults: Blood pressure measurement and diagnosis".)
●(See "Ambulatory blood pressure monitoring: Indications and procedure".)
Impact of hypertension on specific cardiovascular disorders — The magnitude of the association between hypertension and cardiovascular disease varies according to the specific cardiovascular outcome. In one large cohort study, for example, hypertension (which was defined as a blood pressure ≥140/90 mmHg) increased the relative risk of stroke (by 3.8 and 2.6 in males and females, respectively). In addition, heart failure was increased (by 4.0 and 3.0 in males and females, respectively) and to a greater degree than the relative risk of coronary heart disease (by 2.0 and 2.2, respectively) [18].
Projections have been made for the expected decrease in morbidity and mortality with pharmacologic antihypertensive therapy by using data from 48 randomized trials performed over the past 50 years [19]. Based upon this meta-analysis, a 5 mmHg reduction in blood pressure, maintained over a mean of about four years, would approximately translate into a 10 percent reduction in major cardiovascular events, including a 13 percent reduction in stroke, an 8 percent reduction in ischemic heart disease, a 13 percent reduction in incident heart failure, and a 5 percent reduction in cardiovascular death [19]. These estimated relative risk reductions are independent of pre-existing cardiovascular disease or initial blood pressure level (including in those with normal blood pressure). A previous meta-analysis of 123 studies of pharmacologic antihypertensive therapy found that a 10 mmHg reduction in blood pressure reduced the relative risk of coronary heart disease by 17 percent, stroke by 27 percent, heart failure by 28 percent, and all-cause mortality by 13 percent [20]. In both analyses, despite similar relative risk reductions, absolute benefits of blood pressure lowering were greater among those with higher baseline cardiovascular risk and higher baseline blood pressure.
As noted above, the best evidence for a causal role of increasing blood pressure in cardiovascular complications is an improvement in outcome as blood pressure is reduced with antihypertensive therapy [14,19]. (See "Goal blood pressure in adults with hypertension".)
Additive effects of hypertension and other risk factors — The different cardiovascular risk factors have an additive effect on the likelihood of developing coronary heart disease and other cardiovascular outcomes [21,22]. In addition to hypertension, the major risk factors are older age, elevated total and low-density lipoprotein (LDL) cholesterol, a low high-density lipoprotein (HDL) cholesterol, diabetes mellitus, and cigarette smoking. Thus, individual patients who have significant hypertension but none or few of the other risk factors are at relatively lower overall risk than patients with less hypertension but more of the other risk factors (figure 2) [21,23]. (See "Overview of established risk factors for cardiovascular disease".)
Multiple risk prediction models using these and other risk factors have been developed, most notably the Framingham risk score [21,22]. The ability of the Framingham risk criteria to predict cardiovascular disease has been widely reproduced [24-26], but the degree of cardiovascular risk related to the Framingham risk criteria may not apply to all patient populations [27-29]. Other risk factors have been proposed to improve upon the Framingham risk assessment, including C-reactive protein, brain natriuretic peptide, markers of metabolic and kidney disease, echocardiography, and other studies for detecting subclinical vascular disease [30-32]. However, none have been proven to add significantly to the Framingham scoring.
The Predicting Risk of Cardiovascular Disease EVENTs (PREVENT) risk score is a contemporary risk prediction model that has been validated in racially and ethnically diverse populations, unlike previous risk calculators [33]. In addition to the more traditional risk factors, it also includes the risk of heart failure, metabolic and kidney disease markers, and the social deprivation index, a surrogate for social determinants of health. PREVENT is an update to the 2013 pooled cohort equation, an earlier risk prediction model developed by the American Heart Association (AHA) and the American College of Cardiology (ACC) that included the risk of all cardiovascular events, including stroke, rather than coronary heart disease alone, and incorporated data from multiple patient cohorts (calculator 1) [34].
A detailed discussion on the estimation of cardiovascular risk in an individual without known disease is presented separately (see "Atherosclerotic cardiovascular disease risk assessment for primary prevention in adults"). Specific characteristics of risk calculators for formal risk estimation are also presented separately. (See "Cardiovascular disease risk assessment for primary prevention: Risk calculators".)
APPLICATION OF RISK ASSESSMENT TO THERAPEUTIC DECISIONS
Use of baseline cardiovascular risk to guide treatment decisions — A central question in the care of hypertensive patients is whether treatment decisions (eg, use of antihypertensive medications, goal blood pressure) should be applied uniformly to the entire hypertensive population or, instead, tailored according to a patient's risk for future cardiovascular events. The benefit a patient receives from blood pressure lowering depends upon the balance between the absolute (rather than relative) reduction in risk for adverse outcomes and the potential harms and burdens of antihypertensive therapy. (See "Atherosclerotic cardiovascular disease risk assessment for primary prevention in adults" and "Cardiovascular disease risk assessment for primary prevention: Risk calculators".)
Although the relative cardiovascular risk reduction appears to be the same regardless of the baseline cardiovascular risk, the absolute number of cardiovascular events prevented by therapy is significantly greater in the population with higher baseline cardiovascular risk. This concept is presented in detail elsewhere. (See "Goal blood pressure in adults with hypertension".)
A group from New Zealand, for example, took various cardiovascular risk factors into account in determining the overall risk status of individual patients, including their level of blood pressure, age, gender, and other factors (figure 2) [23]. They then examined the evidence of benefits of antihypertensive therapy from the clinical trials and considered the costs of such therapy. They concluded that antihypertensive therapy could be justified only if the risk for a major cardiovascular event over the next five years was 10 percent or greater or if the level of blood pressure was so high as to mandate therapy regardless of overall risk status (≥170/100 mmHg).
Markers of overall cardiovascular risk should be incorporated into treatment decisions, as recommended by several professional organizations [35-37]. As an example, guidelines from the American College of Cardiology/American Heart Association (ACC/AHA) suggest initiating hypertensive medications in higher-risk individuals at lower blood pressures than those with lower overall cardiovascular risk [5]. Details of our approach are presented separately. (See "Goal blood pressure in adults with hypertension".)
As guidelines for incorporating the Predicting Risk of Cardiovascular Disease EVENTs (PREVENT) risk score into clinical practice are being developed, we continue to use the pooled cohort equation for treatment decisions, particularly in patients with stage 1 hypertension (blood pressure 130 to 139/80 to 89 mmHg).
Current risk versus prior risk — Prior risk status, including past average blood pressure, is more responsible for an individual's current health than blood pressure at the time of risk assessment (eg, current blood pressure) [38-40]. Thus, we interpret a patient's current cardiovascular risk estimate alongside the patient's prior health and risk factor status and avoid using a risk calculator as a single data point to predict subsequent events [38].
INFORMATION FOR PATIENTS —
UpToDate offers two types of patient education materials, "The Basics" and "Beyond the Basics." The Basics patient education pieces are written in plain language, at the 5th to 6th grade reading level, and they answer the four or five key questions a patient might have about a given condition. These articles are best for patients who want a general overview and who prefer short, easy-to-read materials. Beyond the Basics patient education pieces are longer, more sophisticated, and more detailed. These articles are written at the 10th to 12th grade reading level and are best for patients who want in-depth information and are comfortable with some medical jargon.
Here are the patient education articles that are relevant to this topic. We encourage you to print or e-mail these topics to your patients. (You can also locate patient education articles on a variety of subjects by searching on "patient info" and the keyword(s) of interest.)
●Beyond the Basics topics (see "Patient education: High blood pressure in adults (Beyond the Basics)" and "Patient education: High blood pressure treatment in adults (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●Hypertension and cardiovascular risk – In terms of population-attributable risk, hypertension is the most significant risk factor for premature cardiovascular disease; it is more important than cigarette smoking, dyslipidemia, and diabetes (table 1). (See 'Introduction' above.)
Hypertension increases the risk for stroke, coronary artery disease, heart failure, atrial fibrillation, abdominal aortic aneurysm, and peripheral vascular disease. The risk for both coronary disease and stroke increases progressively with incremental increases in blood pressure above 115/75 mmHg, as shown in numerous epidemiologic studies (figure 1A-B). However, the best evidence for a causal role of increasing blood pressure in cardiovascular complications is an improvement in outcome with antihypertensive therapy. (See 'Impact of hypertension on cardiovascular disease' above.)
The magnitude of the association between hypertension and cardiovascular disease varies according to the specific cardiovascular outcome. Using data from multiple studies, a 5 and 10 mmHg reduction in systolic pressure is projected to produce a 10 and 20 percent relative risk reduction in major cardiovascular events, respectively, including significant reductions in risk of stroke, coronary disease, heart failure, and cardiovascular death. (See 'Impact of hypertension on specific cardiovascular disorders' above.)
●Additive effects of hypertension and other risk factors – Cardiovascular risk factors have an additive effect on the likelihood of developing coronary heart disease and other cardiovascular outcomes. Multiple risk prediction models using these and other risk factors have been developed, including the Predicting Risk of Cardiovascular Disease EVENTs (PREVENT) risk score. PREVENT has been validated in racially and ethnically diverse populations; it also incorporates the risk of heart failure, metabolic and kidney disease markers, and the social deprivation index, a surrogate for social determinants of health.
PREVENT is an update to the pooled cohort equation, an earlier risk prediction model developed by the American Heart Association (AHA) and the American College of Cardiology (ACC) that included the risk of all cardiovascular events, including stroke, rather than coronary heart disease alone, and incorporated data from multiple patient cohorts (calculator 1). (See 'Additive effects of hypertension and other risk factors' above and "Cardiovascular disease risk assessment for primary prevention: Risk calculators".)
●Application of risk assessment to therapeutic decisions – The benefit a patient receives from blood pressure lowering depends upon the balance between the absolute (rather than relative) reduction in risk for adverse outcomes and the potential harms and burdens of antihypertensive therapy. Markers of overall cardiovascular risk should be incorporated into treatment decisions, as recommended by several professional organizations. (See 'Application of risk assessment to therapeutic decisions' above.)
ACKNOWLEDGMENT —
We are saddened by the death of George Bakris, MD, who passed away in June 2024. UpToDate acknowledges Dr. Bakris' past work as a section editor for this topic.
