BACKGROUND: This is the third update of the review first published in 2017. Hypertension is a prominent preventable cause of premature morbidity and mortality. People with hypertension and established cardiovascular disease are at particularly high risk, so reducing blood pressure to below standard targets may be beneficial. This strategy could reduce cardiovascular mortality and morbidity but could also increase adverse events. The optimal blood pressure target in people with hypertension and established cardiovascular disease remains unknown.
OBJECTIVES: To determine if lower blood pressure targets (systolic/diastolic 135/85 mmHg or less) are associated with reduction in mortality and morbidity compared with standard blood pressure targets (140 mmHg to 160mmHg/90 mmHg to 100 mmHg or less) in the treatment of people with hypertension and a history of cardiovascular disease (myocardial infarction, angina, stroke, peripheral vascular occlusive disease).
SEARCH METHODS: For this updated review, we used standard, extensive Cochrane search methods. The latest search date was January 2022. We applied no language restrictions.
SELECTION CRITERIA: We included randomized controlled trials (RCTs) with more than 50 participants per group that provided at least six months' follow-up. Trial reports had to present data for at least one primary outcome (total mortality, serious adverse events, total cardiovascular events, cardiovascular mortality). Eligible interventions involved lower targets for systolic/diastolic blood pressure (135/85 mmHg or less) compared with standard targets for blood pressure (140 mmHg to 160 mmHg/90 mmHg to 100 mmHg or less). Participants were adults with documented hypertension and adults receiving treatment for hypertension with a cardiovascular history for myocardial infarction, stroke, chronic peripheral vascular occlusive disease, or angina pectoris.
DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used GRADE to assess the certainty of the evidence.
MAIN RESULTS: We included seven RCTs that involved 9595 participants. Mean follow-up was 3.7 years (range 1.0 to 4.7 years). Six of seven RCTs provided individual participant data. None of the included studies was blinded to participants or clinicians because of the need to titrate antihypertensive drugs to reach a specific blood pressure goal. However, an independent committee blinded to group allocation assessed clinical events in all trials. Hence, we assessed all trials at high risk of performance bias and low risk of detection bias. We also considered other issues, such as early termination of studies and subgroups of participants not predefined, to downgrade the certainty of the evidence. We found there is probably little to no difference in total mortality (risk ratio (RR) 1.05, 95% confidence interval (CI) 0.91 to 1.23; 7 studies, 9595 participants; moderate-certainty evidence) or cardiovascular mortality (RR 1.03, 95% CI 0.82 to 1.29; 6 studies, 9484 participants; moderate-certainty evidence). Similarly, we found there may be little to no differences in serious adverse events (RR 1.01, 95% CI 0.94 to 1.08; 7 studies, 9595 participants; low-certainty evidence) or total cardiovascular events (including myocardial infarction, stroke, sudden death, hospitalization, or death from congestive heart failure (CHF)) (RR 0.89, 95% CI 0.80 to 1.00; 7 studies, 9595 participants; low-certainty evidence). The evidence was very uncertain about withdrawals due to adverse effects. However, studies suggest more participants may withdraw due to adverse effects in the lower target group (RR 8.16, 95% CI 2.06 to 32.28; 3 studies, 801 participants; very low-certainty evidence). Systolic and diastolic blood pressure readings were lower in the lower target group (systolic: mean difference (MD) -8.77 mmHg, 95% CI -12.82 to -4.73; 7 studies, 8657 participants; diastolic: MD -4.50 mmHg, 95% CI -6.35 to -2.65; 6 studies, 8546 participants). More drugs were needed in the lower target group (MD 0.56, 95% CI 0.16 to 0.96; 5 studies, 7910 participants), but blood pressure targets at one year were achieved more frequently in the standard target group (RR 1.20, 95% CI 1.17 to 1.23; 7 studies, 8699 participants).
AUTHORS' CONCLUSIONS: We found there is probably little to no difference in total mortality and cardiovascular mortality between people with hypertension and cardiovascular disease treated to a lower compared to a standard blood pressure target. There may also be little to no difference in serious adverse events or total cardiovascular events. This suggests that no net health benefit is derived from a lower systolic blood pressure target. We found very limited evidence on withdrawals due to adverse effects, which led to high uncertainty. At present, evidence is insufficient to justify lower blood pressure targets (135/85 mmHg or less) in people with hypertension and established cardiovascular disease. Several trials are still ongoing, which may provide an important input to this topic in the near future.
BACKGROUND: Stroke is an important cause of death and disability worldwide. Since high blood pressure is an important risk factor for stroke and stroke recurrence, drugs that lower blood pressure might play an important role in secondary stroke prevention.
OBJECTIVES: To investigate whether blood pressure-lowering drugs (BPLDs) started at least 48 hours after the index event are effective for the prevention of recurrent stroke, major vascular events, and dementia in people with stroke or transient ischaemic attack (TIA). Secondary objectives were to identify subgroups of people in which BPLDs are effective, and to investigate the optimum systolic blood pressure target after stroke or TIA for preventing recurrent stroke, major vascular events, and dementia.
SEARCH METHODS: In August 2017, we searched the Trials Registers of the Cochrane Stroke Group and the Cochrane Hypertension Group, the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 8), MEDLINE Ovid (1946 to August 2017), Embase Ovid (1974 to August 2017), ClinicalTrials.gov, the ISRCTN Registry, Stroke Trials Registry, Trials Central, and the World Health Organization (WHO) International Clinical Trials Registry Platform Portal.
SELECTION CRITERIA: Randomised controlled trials (RCTs) of BPLDs started at least 48 hours after stroke or TIA.
DATA COLLECTION AND ANALYSIS: Two review authors independently screened all titles and abstracts, selected eligible trials, extracted the data, assessed risk of bias, and used GRADE to assess the quality of the evidence. If necessary, we contacted the principal investigators or corresponding authors for additional data.
MAIN RESULTS: We included 11 studies involving a total of 38,742 participants: eight studies compared BPLDs versus placebo or no treatment (35,110 participants), and three studies compared different systolic blood pressure targets (3632 participants). The risk of bias varied greatly between included studies. The pooled risk ratios (RRs) of BPLDs were 0.81 (95% confidence interval (CI) 0.70 to 0.93; 8 RCTs; 35,110 participants; moderate-quality evidence), 0.90 (95% CI 0.78 to 1.04; 4 RCTs; 28,630 participants; high-quality evidence) for major vascular event, and 0.88 (95% CI 0.73 to 1.06; 2 RCTs; 6671 participants; high-quality evidence) for dementia. We mainly observed a reduced risk of recurrent stroke in the subgroup of participants using an angiotensin-converting enzyme (ACE) inhibitor or a diuretic (I2 statistic for subgroup differences 72.1%; P = 0.006). The pooled RRs of intensive blood pressure-lowering were 0.80 (95% CI 0.63 to 1.00) for recurrent stroke and 0.58 (95% CI 0.23 to 1.46) for major vascular event.
AUTHORS' CONCLUSIONS: Our results support the use of BPLDs in people with stroke or TIA for reducing the risk of recurrent stroke. Current evidence is primarily derived from trials studying an ACE inhibitor or a diuretic. No definite conclusions can be drawn from current evidence regarding an optimal systolic blood pressure target after stroke or TIA.
IMPORTANCE: Trials in patients with hypertension have demonstrated that intensive blood pressure (BP) lowering reduces the risk of cardiovascular disease and all-cause mortality but may increase the risk of chronic kidney disease (CKD) incidence and progression. Whether intensive BP lowering is associated with a mortality benefit in patients with prevalent CKD remains unknown.
OBJECTIVES: To conduct a systematic review and meta-analysis of randomized clinical trials (RCTs) to investigate if more intensive compared with less intensive BP control is associated with reduced mortality risk in persons with CKD stages 3 to 5.
DATA SOURCES: Ovid MEDLINE, Cochrane Library, EMBASE, PubMed, Science Citation Index, Google Scholar, and clinicaltrials.gov electronic databases.
STUDY SELECTION: All RCTs were included that compared 2 defined BP targets (either active BP treatment vs placebo or no treatment, or intensive vs less intensive BP control) and enrolled adults (≥18 years) with CKD stages 3 to 5 (estimated glomerular filtration rate <60 mL/min/1.73 m2) exclusively or that included a CKD subgroup between January 1, 1950, and June 1, 2016.
DATA EXTRACTION AND SYNTHESIS: Two of us independently evaluated study quality and extracted characteristics and mortality events among persons with CKD within the intervention phase for each trial. When outcomes within the CKD group had not previously been published, trial investigators were contacted to request data within the CKD subset of their original trials.
MAIN OUTCOME AND MEASURE: All-cause mortality during the active treatment phase of each trial.
RESULTS: This study identified 30 RCTs that potentially met the inclusion criteria. The CKD subset mortality data were extracted in 18 trials, among which there were 1293 deaths in 15 924 participants with CKD. The mean (SD) baseline systolic BP (SBP) was 148 (16) mm Hg in both the more intensive and less intensive arms. The mean SBP dropped by 16 mm Hg to 132 mm Hg in the more intensive arm and by 8 mm Hg to 140 mm Hg in the less intensive arm. More intensive vs less intensive BP control resulted in 14.0% lower risk of all-cause mortality (odds ratio, 0.86; 95% CI, 0.76-0.97; P = .01), a finding that was without significant heterogeneity and appeared consistent across multiple subgroups.
CONCLUSIONS AND RELEVANCE: Randomization to more intensive BP control is associated with lower mortality risk among trial participants with hypertension and CKD. Further studies are required to define absolute BP targets for maximal benefit and minimal harm.
IMPORTANCE: The optimal blood pressure (BP) target remains debated in nondiabetic patients with chronic kidney disease (CKD).
OBJECTIVE: To compare intensive BP control (<130/80 mm Hg) with standard BP control (<140/90 mm Hg) on major renal outcomes in patients with CKD without diabetes.
DATA SOURCES: Searches of PubMed, MEDLINE, Embase, and Cochrane Library for publications up to March 24, 2016.
STUDY SELECTION: Randomized clinical trials that compared an intensive vs a standard BP target in nondiabetic adults with CKD, reporting changes in glomerular filtration rate (GFR), doubling of serum creatinine level, 50% reduction in GFR, end-stage renal disease (ESRD), or all-cause mortality.
DATA EXTRACTION AND SYNTHESIS: Random-effects meta-analyses for pooling effect measures. Meta-regression and subgroup analyses for exploring heterogeneity.
MAIN OUTCOMES AND MEASURES: Differences in annual rate of change in GFR were expressed as mean differences with 95% CIs. Differences in doubling of serum creatinine or 50% reduction in GFR, ESRD, composite renal outcome, and all-cause mortality were expressed as risk ratios (RRs) with 95% CIs.
RESULTS: We identified 9 trials with 8127 patients and a median follow-up of 3.3 years. Compared with standard BP control, intensive BP control did not show a significant difference on the annual rate of change in GFR (mean difference, 0.07; 95% CI, -0.16 to 0.29 mL/min/1.73 m2/y), doubling of serum creatinine level or 50% reduction in GFR (RR, 0.99; 95% CI, 0.76-1.29), ESRD (RR, 0.96; 95% CI, 0.78-1.18), composite renal outcome (RR, 0.99; 95% CI, 0.81-1.21), or all-cause mortality (RR, 0.95; 95% CI, 0.66-1.37). Nonblacks and patients with higher levels of proteinuria showed a trend of lower risk of kidney disease progression with intensive BP control.
CONCLUSIONS AND RELEVANCE: Targeting BP below the current standard did not provide additional benefit for renal outcomes compared with standard treatment during a follow-up of 3.3 years in patients with CKD without diabetes. However, nonblack patients or those with higher levels of proteinuria might benefit from the intensive BP-lowering treatments.
BACKGROUND: Recent guidelines recommend a systolic blood pressure (SBP) goal of less than 150 mm Hg for adults aged 60 years or older, but the balance of benefits and harms is unclear in light of newer evidence.
PURPOSE: To systematically review the effects of more versus less intensive BP control in older adults.
DATA SOURCES: Multiple databases through January 2015 and MEDLINE to September 2016.
STUDY SELECTION: 21 randomized, controlled trials comparing BP targets or treatment intensity, and 3 observational studies that assessed harms.
DATA EXTRACTION: Two investigators extracted data, assessed study quality, and graded the evidence using published criteria.
DATA SYNTHESIS: Nine trials provided high-strength evidence that BP control to less than 150/90 mm Hg reduces mortality (relative risk [RR], 0.90 [95% CI, 0.83 to 0.98]), cardiac events (RR, 0.77 [CI, 0.68 to 0.89]), and stroke (RR, 0.74 [CI, 0.65 to 0.84]). Six trials yielded low- to moderate-strength evidence that lower targets (≤140/85 mm Hg) are associated with marginally significant decreases in cardiac events (RR, 0.82 [CI, 0.64 to 1.00]) and stroke (RR, 0.79 [CI, 0.59 to 0.99]) and nonsignificantly fewer deaths (RR, 0.86 [CI, 0.69 to 1.06]). Low- to moderate-strength evidence showed that lower BP targets do not increase falls or cognitive impairment.
LIMITATION: Data relevant to frail elderly adults and the effect of multimorbidity are limited.
CONCLUSION: Treatment to at least current guideline standards for BP (<150/90 mm Hg) substantially improves health outcomes in older adults. There is less consistent evidence, largely from 1 trial targeting SBP less than 120 mm Hg, that lower BP targets are beneficial for high-risk patients. Lower BP targets did not increase falls or cognitive decline but are associated with hypotension, syncope, and greater medication burden.
PRIMARY FUNDING SOURCE: U.S. Department of Veterans Affairs, Veterans Health Administration, Office of Research and Development, Quality Enhancement Research Initiative. (PROSPERO 2015: CRD42015017677).
This is the third update of the review first published in 2017. Hypertension is a prominent preventable cause of premature morbidity and mortality. People with hypertension and established cardiovascular disease are at particularly high risk, so reducing blood pressure to below standard targets may be beneficial. This strategy could reduce cardiovascular mortality and morbidity but could also increase adverse events. The optimal blood pressure target in people with hypertension and established cardiovascular disease remains unknown.
OBJECTIVES:
To determine if lower blood pressure targets (systolic/diastolic 135/85 mmHg or less) are associated with reduction in mortality and morbidity compared with standard blood pressure targets (140 mmHg to 160mmHg/90 mmHg to 100 mmHg or less) in the treatment of people with hypertension and a history of cardiovascular disease (myocardial infarction, angina, stroke, peripheral vascular occlusive disease).
SEARCH METHODS:
For this updated review, we used standard, extensive Cochrane search methods. The latest search date was January 2022. We applied no language restrictions.
SELECTION CRITERIA:
We included randomized controlled trials (RCTs) with more than 50 participants per group that provided at least six months' follow-up. Trial reports had to present data for at least one primary outcome (total mortality, serious adverse events, total cardiovascular events, cardiovascular mortality). Eligible interventions involved lower targets for systolic/diastolic blood pressure (135/85 mmHg or less) compared with standard targets for blood pressure (140 mmHg to 160 mmHg/90 mmHg to 100 mmHg or less). Participants were adults with documented hypertension and adults receiving treatment for hypertension with a cardiovascular history for myocardial infarction, stroke, chronic peripheral vascular occlusive disease, or angina pectoris.
DATA COLLECTION AND ANALYSIS:
We used standard Cochrane methods. We used GRADE to assess the certainty of the evidence.
MAIN RESULTS:
We included seven RCTs that involved 9595 participants. Mean follow-up was 3.7 years (range 1.0 to 4.7 years). Six of seven RCTs provided individual participant data. None of the included studies was blinded to participants or clinicians because of the need to titrate antihypertensive drugs to reach a specific blood pressure goal. However, an independent committee blinded to group allocation assessed clinical events in all trials. Hence, we assessed all trials at high risk of performance bias and low risk of detection bias. We also considered other issues, such as early termination of studies and subgroups of participants not predefined, to downgrade the certainty of the evidence. We found there is probably little to no difference in total mortality (risk ratio (RR) 1.05, 95% confidence interval (CI) 0.91 to 1.23; 7 studies, 9595 participants; moderate-certainty evidence) or cardiovascular mortality (RR 1.03, 95% CI 0.82 to 1.29; 6 studies, 9484 participants; moderate-certainty evidence). Similarly, we found there may be little to no differences in serious adverse events (RR 1.01, 95% CI 0.94 to 1.08; 7 studies, 9595 participants; low-certainty evidence) or total cardiovascular events (including myocardial infarction, stroke, sudden death, hospitalization, or death from congestive heart failure (CHF)) (RR 0.89, 95% CI 0.80 to 1.00; 7 studies, 9595 participants; low-certainty evidence). The evidence was very uncertain about withdrawals due to adverse effects. However, studies suggest more participants may withdraw due to adverse effects in the lower target group (RR 8.16, 95% CI 2.06 to 32.28; 3 studies, 801 participants; very low-certainty evidence). Systolic and diastolic blood pressure readings were lower in the lower target group (systolic: mean difference (MD) -8.77 mmHg, 95% CI -12.82 to -4.73; 7 studies, 8657 participants; diastolic: MD -4.50 mmHg, 95% CI -6.35 to -2.65; 6 studies, 8546 participants). More drugs were needed in the lower target group (MD 0.56, 95% CI 0.16 to 0.96; 5 studies, 7910 participants), but blood pressure targets at one year were achieved more frequently in the standard target group (RR 1.20, 95% CI 1.17 to 1.23; 7 studies, 8699 participants).
AUTHORS' CONCLUSIONS:
We found there is probably little to no difference in total mortality and cardiovascular mortality between people with hypertension and cardiovascular disease treated to a lower compared to a standard blood pressure target. There may also be little to no difference in serious adverse events or total cardiovascular events. This suggests that no net health benefit is derived from a lower systolic blood pressure target. We found very limited evidence on withdrawals due to adverse effects, which led to high uncertainty. At present, evidence is insufficient to justify lower blood pressure targets (135/85 mmHg or less) in people with hypertension and established cardiovascular disease. Several trials are still ongoing, which may provide an important input to this topic in the near future.
