Mrs. Weymouth has hypertension and she is at your office for a check-up. Her blood pressure is 136/72 mm Hg. What do you tell her about her blood pressure control?
Hypertension affects nearly 1 out of 2 individuals world-wide between the ages of 35 and 70. The goal of blood pressure control is to reduce cardiovascular and renal morbidity and mortality. The most recent blood pressure guideline (JNC-8) published in 2014 recommended a blood pressure goal of < 140/90 mm Hg for those under age 60 and < 150/90 mm Hg for those over age 60. For individuals with diabetes or chronic kidney disease the goal is < 140/90 mm Hg.
Should the blood pressure goal be lower than these values? After all, some observational data have suggested better cardiovascular outcomes when blood pressure is as low as 115 mm Hg systolic.
Wright and colleagues conducted a NIH-funded study called SPRINT in over 90 sites in the US including Puerto Rico, which helped answer this question.
SPRINT randomized over 9300 individuals to one of two systolic blood pressure goals: < 120 mm Hg (intensive treatment) or < 140 mm Hg (standard treatment). The primary outcome was the composite of myocardial infarction, acute coronary syndrome, stroke, acute decompensated heart failure, and cardiovascular death.
The study was stopped early due to the significant benefit seen with intensive treatment. The systolic blood pressure achieved was about 121 mm Hg (intensive) versus 136 mm Hg (standard). Individuals took an average of 2.8 versus 1.8 blood pressure medications in the intensive and standard treatment groups, respectively. Intensive treatment resulted in a significantly lower rate of the primary outcome (1.65%/yr versus 2.17%/yr). The outcome was mostly driven by acute heart failure and cardiovascular death (HR 0.62 and HR 0.57, respectively). There were significant differences in the occurrence of serious adverse events due to hypotension (HR 1.67), syncope (HR 1.33), electrolyte abnormality (HR 1.35), and acute kidney injury (HR 1.66).
So does the SPRINT result apply to everyone? In an NEJM Perspective article, Chobanian from Boston University cautions that the “SPRINT results are not applicable to patients with diabetes, those with prior stroke, or institutionalized elderly people, all of whom were excluded from the study.” The previous ACCORD study in individuals with diabetes and high cardiovascular risk showed that treating to a systolic blood pressure to < 120 mm Hg had no cardiovascular benefit. However, in an editorial, Perkovic and Rodgers from the George Institute in Sydney, Australia argue that the benefits should be understood more broadly, and suggest that the results of SPRINT and ACCORD are actually consistent with significant benefit in both settings.
Should Mrs. Weymouth’s blood pressure be lowered? What factors do you consider in this decision? Read 2 experts’ opposing viewpoints on how low to target blood pressure in the Clinical Decisions and cast your vote and leave your comments.
See also a new NEJM Quick Take on the SPRINT trial results.