Is lower BP worth it in higher-risk patients with diabetes or coronary disease?

The SPRINT trial: Promising results for intensive treatment of some patients

The Systolic Blood Pressure Intervention Trial (SPRINT), a large RCT, found that targeting systolic blood pressures below 120 mm Hg (compared with a target below 140 mm Hg) in middle-aged and older patients with increased cardiovascular risk reduced a composite outcome that included cardiovascular death by 25%.⁴

Researchers recruited 9361 patients older than 50 years (mean age 68 years; >28% older than 75 years) with systolic blood pressure between 130 and 180 mm Hg and increased cardiovascular risk defined by one or more of the following: preexisting cardiovascular disease, CKD with estimated glomerular filtration rate between 20 and 60 mL/min/1.73 m², age >75 years, and Framingham 10-year risk of 15% or more. They excluded patients with diabetes or previous stroke.

Patients were randomized to intensive treatment (target systolic BP <120; mean achieved 121.4) or standard treatment (target systolic BP <140; mean achieved 136.2). Treatment typically comprised 3 (intensive) or 2 (standard) agents. The primary outcome was a composite of myocardial infarction, acute coronary syndrome, stroke, congestive heart failure, or cardiovascular death.

The study, which was originally intended to run for 5 years, was stopped at 3.26 years based on positive results. Intensive treatment improved the primary composite outcome overall (1.65% vs 2.19%; HR=0.75; 95% CI, 0.64-0.89; P<.001; NNT=61 over 3.26 years), all-cause mortality (HR=0.73; 95% CI, 0.60-0.90; P=.003; NNT=90), and cardiovascular death (HR=0.57; 95% CI, 0.38-0.85; P=.005; NNT=172).

However, intensive treatment didn’t significantly improve the primary composite outcome in these subgroups:

• female patients (HR=0.84; 95% CI, 0.62-1.14)
• black patients (HR=0.77; 95% CI, 0.55-1.06)
• patients with preexisting CKD (HR=0.82; 95% CI, 0.63-1.07) or cardiovascular disease (HR=0.83; 95% CI, 0.62-1.09)
• patients younger than 75 years (HR=0.80; 95% CI, 0.64-1.00)
• patients with systolic blood pressures higher than 132 mm Hg (BP >132 to <145 mm Hg, HR=0.77; 95% CI, 0.57-1.03; BP ≥145 mm Hg, HR=0.83; 95% CI, 0.63-1.09).

While the SPRINT study found that targeting systolic BP below 120 mm Hg reduced a composite outcome that included cardiovascular death, it didn’t improve this outcome in certain patient subgroups.

Intensive treatment also produced more net serious adverse events (HR=1.88; 4.7% vs 2.5%; P<.001), including: ≥30% decrease of glomerular filtration rates to values below 60 mL/min/1.73 m² (HR=3.49; 95% CI, 2.44-5.10; P<.001), syncope (HR=1.44; 3.5% vs 2.4%; P=.003), hypotension (HR=1.70; 3.4% vs 2.0%; P<.001), and electrolyte abnormalities (HR=1.38; 3.8% vs 2.8%; P=.006). It didn’t cause injurious falls (HR=1.00; P=.97) or orthostatic hypotension in clinic (HR=0.88; 16.6% vs 18.3%; P=.01).

Guidelines for patients with peripheral artery disease, previous stroke

A national guideline by an expert panel recommended treating patients with hypertension who have peripheral artery disease or previous stroke to standard values for the general population: <140/90 mm Hg if ages 60 years or younger, <150/90 mm Hg if older than 60 years.⁵