Throughout the study, mean SBP was 121.5 mm Hg in the intensive therapy group and 134.6 mm Hg in the standard treatment group. This required an average of one additional BP medication in the intensive therapy group (2.8 vs 1.8, respectively).1
Lower SBP produces mortality benefits in those under, and over, age 75
This trial builds on a body of evidence that shows the advantages of lowering SBP to <150 mm Hg7,11,12 by demonstrating benefits, including lower all-cause mortality, for lower SBP targets in non-diabetic patients at high risk of CV disease. The SPRINT trial also showed that the benefits of intensive therapy remained true in a subgroup of patients ≥75 years of age.
The incidence of the primary outcome in the cohort ≥75 years of age receiving intensive therapy was 7.7% vs 10.9% for those receiving standard therapy (HR=0.67; 95% CI, 0.51-0.86; NNT=31). All-cause mortality was also lower in the intensive therapy group than in the standard therapy group among patients ≥75 years of age: 5.5% vs 8.04% (HR=0.68; 95% CI, 0.50-0.92; NNT=38).1
Many do not benefit from—or are harmed by—increased medication
The absolute risk reduction for the primary outcome is 1.6%, meaning 98.4% of patients receiving more intensive treatment will not benefit. In a group of 1000 patients, an estimated 16 patients will benefit, 22 patients will be seriously harmed, and 962 patients will experience neither benefit nor harm.14 The difference between how BP was measured in this trial (an average of 3 readings after the patient had rested for 5 minutes) and that which occurs typically in clinical practice could potentially lead to overtreatment in practice.
Also, reducing antihypertensive therapies when the SBP was about 130 to 135 mm Hg in the standard therapy group likely exaggerated the difference in outcomes between the intensive and standard therapy groups, and is neither routine nor recommended in clinical practice.6 Finally, the trial specifically studied non-diabetic patients at high risk of CV disease ≥50 years of age, limiting generalizability to other populations.
Challenges to implementation
Who will benefit/who can achieve intensive SBP goals?
Identifying patients most likely to benefit from more intensive BP targets remains challenging. The SPRINT trial showed a mortality benefit, but at a cost of increased morbidity.1,14 In particular, caution should be exercised in the subgroup of patients ≥75 years. Despite a lower NNT than the rest of the study population, serious adverse events happened more frequently. Also, this particular cohort of volunteers may not be representative of those ≥75 years of age in the general population.
Additionally, achieving intensive SBP goals can be challenging. In the SPRINT trial, only half of the intensive target group achieved an SBP <120 mm Hg.1 And in a 2011-12 National Health and Nutrition Examination Survey, only 52% of patients in the general population achieved a BP target <140/90 mm Hg.15 Lower morbidity and mortality should remain the ultimate goals to the management of hypertension, requiring physicians to carefully assess an individual patient’s likelihood of benefit vs harm.
The PURLs Surveillance System was supported in part by Grant Number UL1RR024999 from the National Center For Research Resources, a Clinical Translational Science Award to the University of Chicago. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Center For Research Resources or the National Institutes of Health.