Blood Pressure: How Low is Low Enough

A new clinical trial published in the New England Journal of Medicine called the SPRINT Trial ( Systolic Blood Pressure Intervention Trial ) which compares standard treatment of hypertension to a goal of a systolic BP < 140 compared to more aggressive treatment to a goal of systolic BP <120 was published on Nov. 9, 2015.  It raises many questions and makes the most recent JAH – 8 recommendations subject to reevaluation.  In the SPRINT Trial almost 10,000 patients with hypertension felt to be at high risk to have a heart attack or stroke were randomly divided into two groups.  Standard treatment was to treat to a goal BP of <140 systolic.  Aggressive treatment was to treat to a goal of systolic BP <120. Patients with diabetes were excluded as were patients with a prior stroke.

The SPRINT Trial was stopped early because the results were felt to be definitive and showed a reduced risk of death, death from cardiovascular events like heart attack or stroke, and risk of having a non-fatal heart attack or stroke were all lower in the aggressive treatment group.  The statistical chance of an individual having a better outcome with more aggressive treatment is modest.  It would take treating 61 patients (Number needed to treat = NNN) to a goal BP of 120 vs 140 to prevent one heart attack or stroke, and the NNN for death from any cause was 90, and for cardiovascular death was 172.

The risk of serious adverse effects of medication including fainting, low blood pressure, non-fatal acute reduction in kidney function, electrolyte abnormality (low sodium or low potassium), or slow heart rate were slightly higher in the aggressive treatment group, and this group required on average about 1 additional prescription medication.

When JNC-8 (Joint National Committee on treatment of hypertension- 8th report) was released in 2014 the major change in hypertension treatment recommendations was less aggressive treatment for systolic hypertension in older patients (>60 yo) and in diabetic patients.  They recommended settling for a systolic BP of <150 in patients over 60 yo and for a systolic BP of 140 (vs the prior goal of <130) for diabetics.

Where all of this will fall out in practice remains in question, but I think pushing patients to a goal systolic BP of <120 is going to become more common, although even in this study the aggressive treatment group achieved an average systolic BP of only 121.  It is widely believed that less than half of Americans with hypertension achieve a goal of <140 currently.  Obviously it’s not going to be easy to achieve a goal of systolic BP <120 for many patients,  but at a minimum I think backing off on BP treatment for patients whose systolic BP gets into the 100-120 range and is assymptomatic is no longer reasonable, even when patients complain about how many pills they are taking and whether any of their meds can be stopped.
 

One Response to Blood Pressure: How Low is Low Enough

  1. There is a common myth that people with high BP or hypertension can experience symptoms such as nervousness, sweating or difficulty sleeping. Whereas the truth is high blood pressure is a symptomless condition. At the same time, some symptoms do evaluate towards hypertension and in such case one must get him or herself diagnosed

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