Tools for Practice


#37 SPRINT don’t walk to Evidence for Specific BP Targets?


CLINICAL QUESTION
What is the evidence for blood pressure (BP) targets lower than 140/90?

BOTTOM LINE
Evidence supports BP targets of <140/90 for general hypertension and diabetic/renal subgroups. However, in patients with cardiovascular disease (CVD) risk ≥20% over 10 years, targets ~120 can be (carefully) considered. This does not include diabetics or post-stroke and standing BP should be monitored.


CFPCLearn Logo

Reading Tools for Practice Article can earn you MainPro+ Credits

Join Now

Already a CFPCLearn Member? Log in



EVIDENCE
Outcomes Statistically Significant:
  • SPRINT:1 Randomized Controlled Trial (RCT) of 9,361 patients (CVD risk ~20% over ten years), target <140 versus <120, x3.3 years. Attained BP 136/76 versus 121/68 and average patient on 2.8 versus 1.8 medications.
    • CVD: 25% Relative Risk Reduction (RRR), Number Needed to Treat (NNT)=61.
    • Death: 27% RRR, NNT=90.
      • Similar benefits elderly (age ≥75) and other groups (example renal).
    • No diabetics, post-stroke, ejection fraction <35%, GFR <20, or standing BP <110.
  • General Hypertension, three Systematic Reviews (SR).2-4
    • Seven RCTs (22,089 patients)2 x3.8 years: Intense BP 4/3 lower.
      • No statistical differences in outcomes.
    • Nineteen RCTs (44,989 patients) x3.8 years:3 Attained BP 133/76 versus 140/81.
      • Death: No statistical difference.
      • CVD: RRR 14% (if CVD risk ~20% over 10 year, NNT=36).
    • Sixteen RCTs (52,235 patients)4 x3.7 years: Intense BP 8/3 lower, “standardized” to 10/5.
      • CVD: 25% RRR (if CVD risk ~20% over 10 years, NNT=28).
      • Limits: Some early trials not “intense” (example ≤150 systolic versus ≤180).3,4
  • Type II Diabetes: Two SR of five RCTs (7,314 patients) x4.5 years.5,6 BP Systolic target RCTs 119/64 versus 135/83 and diastolic target RCTs 128/76 versus 133/70.
    • Stroke: RRR 35%, NNT ~31 over ten years.
    • Death and other CVD: No statistical difference.
    • Two SR examined attained BP.7,8
      • Benefits for reduction <140 but ≤130 minimal stroke reductions lost against increased CVD mortality7 or serious adverse events.8
  • Renal Disease: Two SR of 3-11 RCTs (2,272-9,287 patients)9,10 ~3 years. Systolic BP ~10 lower in intense.
    • Mortality or any CVD: No statistical difference.
    • Prevent worsening renal function:9 RRR 18%, NNT=247.
Context:
  • Harms (intense versus standard):1 Hypotension (Number Needed to Harm (NNH)=72), syncope (NNH=91), acute kidney injury (NNH=56).
  • Large SR demonstrate absolute benefits of BP reduction are driven largely by baseline risk.11,12
  • Guideline13 recommended Systolic BP targets vary between 130-150.
  • If lower targets used: Advise of potential harms, monitor carefully, check standing BP.
  Reviewed Mar 25 2016
November 22, 2010

This content is certified for MainPro+ Credits, log in to access

Author(s):

  • G. Michael Allan MD CCFP
  • Raj S. Padwal MD MSc FRCP(C)

1. Cochrane Database of Systematic Reviews 2009, Issue 3. Art. No.: CD004349. DOI: 10.1002/14651858.CD004349.pub2

2. N Engl J Med. 2010 Apr 29;362(17):1575-85

3. Lancet 2009; 374: 525–33

4. N Engl J Med 2010;363:918-29

5. Curr Hypertens Rep (2010) 12:290–295

6. The Seventh Report of the Joint National Committee on: Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. August 2004.

7. 2009 Canadian Hypertension Education Program Recommendations: The Scientific Summary. 2009. (Web Link)

8. J Hypertension 2009, 27:2121–2158

9. Curr Opin Cardiol. 2010 Jul;25(4):350-4

10. Feldstein C, Julius S. Establishing Targets for Hypertension Control in Patients with Comorbidities. Curr Hypertens Rep. 2010 Dec;12(6):465-73.

Authors do not have any conflicts of interest to declare.