Blood Pressure Treatment Goals

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Why is a treatment goal important for hypertension?

Hypertension is the most important risk factor for cardiovascular disease (CVD) and stroke worldwide. Epidemiological studies demonstrate that blood pressure (BP) is continuously related to the risk of fatal stroke, ischemic heart disease (IHD), and noncardiac vascular disease well down into the normal range (beginning at 115/75 mm Hg). For example, a 20-mm Hg higher systolic blood pressure (SBP) or a 10-mm Hg higher diastolic blood pressure (DBP) associates with a doubling of the risk for a fatal cardiovascular event.

Control of BP to an established target is critical to prevent CVD events and mortality. Specifically, suboptimal BP control (above target) is the most common attributable risk factor for death worldwide, being responsible for approximately 62% of CVD, 49% of IHD, and 7.1 million deaths annually.

Randomized controlled trials (RCTs) have confirmed that the risk of CVD can be greatly reduced with effective antihypertensive therapy. For example, a 10-mm Hg lower SBP or a 5-mm Hg lower DBP results in approximately a 40% reduction in stroke risk and a 30% reduction in IHD risk.

A BP treatment goal represents the average optimum BP level for CVD prevention based on current evidence and balanced against the occurrence of detrimental side effects resulting from the BP reduction itself and/or the treatment. BP treatment goals are derived from results of RCTs, which represent aggregate responses of their study populations. Therefore BP goals are intended as general guides, and, with this knowledge, individual BP goals should be set by the clinician in consultation with the patient.

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What was the established treatment goal up to 2017, and what was the evidence?

The treatment goals prior to 2017 were established in 2003 by the Joint National Committee (JNC)-7 Report. The general goal was BP less than 140/90 mm Hg and less than 130/80 mm Hg for patients with diabetes mellitus (DM) and/or chronic kidney disease (CKD). In 2003 the evidence was largely derived from the Hypertension Optimal Treatment (HOT) clinical trial (1998) and the Blood Pressure Lowering Treatment Trialists Collaboration clinical trials (2000), which recorded, for example, a 35% to 40% reduction in stroke incidence at this level of BP control. A sustained 12-mm Hg lowering of SBP resulted in 1 life saved of 11 patients treated, and this number increased to 1 in 9 if background CVD or target-organ damage was present.

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What new findings contributed to the establishment of new BP treatment goals in 2017?

In 2015 the results of the landmark Systolic Blood Pressure Intervention Trial (SPRINT) were published. SPRINT randomized over 9000 patients with hypertension of 50 years of age or older with background CVD or high CVD risk to more intensive (goal SBP <120 mm Hg) or less intensive (goal SBP <140 mm Hg) BP-lowering treatment. Patients with DM or prior stroke were excluded. The trial was halted early after the Data Safety Monitoring Board revealed a 25% lower risk of fatal and nonfatal major CVD events and a 27% lower risk of death from any cause in the intensive BP-lowering arm. The SPRINT results have been accepted worldwide as providing convincing evidence that treatment to a lower BP goal, at least in adults at high CVD risk, prevents CVD events and death.

In addition to SPRINT, several high-quality systematic reviews and metaanalyses of RCTs bearing on BP goal were published in 2016–17 (results summarized in Table 30.1 ). In a metaanalysis reported by Xie et al., which did not include SPRINT, more intensive BP lowering to an average BP of 133/76 mm Hg reduced major CVD events (risk ratio [RR], 0.86; 95% confidence interval [CI], 0.78–0.96) compared to less intensive BP control (BP 140/81 mm Hg). A systematic review and metaanalysis by Thomopoulos et al. stratified outcomes by BP achieved in trials that employed more versus less intense BP lowering. Comparing those who achieved an SBP of less than 130 mm Hg to those achieving an SBP of 130 mm Hg or higher, the RR for stroke was 0.71 (95% CI, 0.61–0.84), for cardiovascular death was 0.80 (95% CI, 0.67–0.97), and for all-cause mortality was 0.84 (95% CI, 0.73–0.95). In a cumulative sequential metaanalysis by Verdecchia et al., more (BP 129/76 mm Hg) compared to less (BP 138/81 mm Hg) BP lowering resulted in an RR for stroke of 0.80 (95% CI, 0.67–0.95) and for myocardial infarction (MI) of 0.85 (95% CI, 0.76–0.95). A network metaanalysis by Bangalore et al., restricted to 17 trials in which participants were randomly assigned to different BP targets, demonstrated progressive benefit with lower BP targets down to an SBP of less than 120 mm Hg for both CVD outcomes and mortality.

The highest quality network metaanalysis available included 42 randomized controlled two-arm trials with 144,220 adults in which the more and less intensively treated groups had an SBP that differed by 5 mm Hg or more in randomized comparisons. A progressive reduction in CVD risk was observed at lower levels of achieved SBP, including major CVD events, stroke, IHD, and all-cause mortality. Similar findings were observed when direct metaanalysis was employed and in sensitivity analyses with the SPRINT results excluded.

Finally, the independent Evidence Review Committee (ERC) for the 2017 American College of Cardiology/American Heart Association (ACC/AHA) BP guideline conducted a thorough systematic review and metaanalysis of more versus less intensive BP lowering in RCTs. The metaanalysis demonstrated a consistent pattern of benefit of intensive BP lowering for all CVD outcomes and all-cause mortality. Intensive BP lowering significantly reduced the risk of major adverse cardiovascular events (MACE) (RR, 0.81; 95% CI, 0.70–0.94) as well as MI, stroke, and heart failure. To identify the optimal target for BP reduction, the ERC examined the risk reduction of these outcomes for RCTs with an SBP target of less than 130 mm Hg in the lower BP target group and again found a significantly reduced risk of stroke (RR, 0.82; 95% CI, 0.70–0.96) and MACE (RR, 0.84; 95% CI, 0.73–0.99) with marginally significant reductions in risk of MI (RR, 0.85; 95% CI, 0.73–1.00) and all-cause mortality.

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What is the new general BP treatment goal for hypertension?

The new general BP treatment goal is less than 130/80 mm Hg, as recommended by the 2017 ACC/AHA guideline. These BP goals are intended as general guides, and, with this knowledge, individual BP goals should be set by the clinician in consultation with the patient.

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