Summaries of Must-Read Clinical Literature, Guidelines, and FDA Actions
BP Measurement Methods and Treating Targets
Circulation; 2016 Sep 27; Bakris, et al
In this perspective article focused on the implications of blood pressure (BP) measurement methods on treatment targets for BP, the author references several clinical outcome trials that have evaluated the effects of BP reduction on cardiovascular outcomes, including the recent SPRINT (Systolic Blood Pressure Intervention Trial) which provided evidence that the goal of systolic blood pressure (SBP) should be closer to 120 than 140 mmHg. However, the author notes, the methods of BP measurement used in this trial were different than many others. Also, the methodology for measuring BP in SPRINT is not the same as what is used in most clinical practices, which could have clinical implications.
Most other research studies, and most clinical practices, measure BP shortly after the patient is put in the exam room. In the SPRINT trial BP was measured after the having the patient sit quietly alone for 5 minutes, and then measuring BP 3 times at 1-minute intervals with all 3 values averaged. In the opinion of the author of the perspective article, BP measured in this manner is likely 5 to 10 mmHg lower than that which would have been obtained in the same patients if the usual clinical method of measuring blood pressure were used. The author recommends that if standard office BP measurement is used without a resting period and without automatic cycling of measurements with clinic personnel out of the room, the goal SBP ranges for those meeting risk profiles similar to SPRINT should be adjusted 5 to 10 mmHg higher than the trials. In other words, targeting a BP goal < 120 mmHg using measurements in the office might overshoot a goal BP based on the SPRINT trial.
Bakris GL. The implications of blood pressure measurement methods on treatment targets for blood pressure. Circulation. 2016;134:904-905. doi:
It has been hard to reconcile the results of the SPRINT Trial with the results of most other trials looking at blood pressure goals in the treatment of hypertension, including HOPE-3 and ACCORD. The SPRINT trial showed that treating to a systolic BP <120 mm Hg vs <140 mm Hg led to lower rates of fatal and nonfatal major cardiovascular events and death.1 In the ACCORD trial, looking at patients with diabetes and hypertension, targeting a BP <120 mm Hg vs <140 mm Hg did not lead to a lower CV event rate.2 Finally, the HOPE-3 Trial, which looked at patients at intermediate cardiac risk, showed that more aggressive blood pressure lowering in patients with a baseline BP=138 did not yield a better CV outcome.3 There are many differences between these trials, making it important to be cautious about generalizing the surprising results of SPRINT to populations other than the very high risk population that it looked at, all of whom had existent CV disease, chronic kidney disease (GFR <60 ml/min), or a calculated 10-year risk of CV disease of >15%. This perspective article adds an additional note of caution, hidden in the details of the SPRINT trial—that the method of BP measurement used in this trial was different than that used in other trials and then that used in most office settings. A recent trial published in the Lancet showed that in patients with hypertension and coronary artery disease in clinical practices, systolic BP <120 mmHg and diastolic BP <70 mmHg were associated with adverse cardiovascular outcomes and increased mortality.4 We should use caution before changing BP goals to that used in the SPRINT Trial. —Neil Skolnik, MD
1. Wright JT Jr., Williamson JD, Whelton PK, et al. SPRINT Research Group. A randomized trial of intensive versus standard blood-pressure control. N Engl J Med. 2015;373(22):2103-2116.
2. The ACCORD Study Group. Effects of intensive blood-pressure control in type 2 diabetes mellitus. N Engl J Med. 2010;362:1575-1585. doi:10.1056/NEJMoa1001286.
3. Lonn EM, Bosch J, López-Jaramillo P, et al. Blood-pressure lowering in the intermediate-risk persons without cardiovascular disease. N Engl J Med. 2016;374:2009-2020. doi:10.1056/NEJMoa1600175.
4. Vidal-Petiot E, Ford I, Greenlaw N, et al. Cardiovascular event rates and mortality according to achieved systolic and diastolic blood pressure in patients with stable coronary artery disease: An international cohort study. [Published online ahead of print August 30, 2016]. Lancet. doi:10.1016/S0140-6736(16)31326-5.