Dizziness, lightheadedness not affected by lower goal
NEW ORLEANS -- A lower systolic blood pressure (BP) target was associated with less orthostatic hypotension, but no difference in symptoms, among stroke survivors, according to an analysis of the SPS3-BP trial.
Compared with a group with a standard systolic BP target of 130-149 mm Hg, those randomized to intensive BP lowering (goal <130 mm Hg) after their index stroke showed:
- Lower risk of orthostatic hypotension: OR 0.86 (95% CI 0.75-0.99)
- Similar risk of dizziness while standing: OR 0.96 (95% CI 0.77-1.18)
- Similar risk of lightheadedness while standing: OR 0.97 (95% CI 0.76-1.24)
"A lower systolic BP goal decreased orthostatic hypotension without affecting orthostatic symptoms. These findings support recent observations that more intensive systolic BP treatment does not increase risk of falls," concluded Stephen Juraschek, MD, PhD, of Beth Israel Deaconess Medical Center in Boston, in a presentation at the American Heart Association annual Hypertension meeting.
Yet it's a complex issue as high BP can cause a variety of symptoms, including ones similar to low BP, commented Paola Sandroni, MD, PhD, of the Mayo Clinic in Rochester, Minnesota.
The point here is to control BP appropriately after stroke, which, if properly done, won't cause more orthostatic hypotension, she told MedPage Today.
The SPS3-BP trial included more than 3,000 patients who had had a recent MRI-confirmed, non-disabling lacunar stroke (mean age 62.8; 37% women). Participants were enrolled from 81 centers in North America, Latin America, and Spain in 2003-2011.
Each person underwent 15 orthostatic hypotension assessments on average over 3.7 years of follow-up, each time having BP measured three times in a seated position, then once after 2 minutes of standing. Orthostatic hypotension was defined as drop of systolic BP ≥20 mm Hg (or diastolic BP reduction by 10 mm Hg) after 2 minutes of the patient standing up.
Over 40% of SPS3-BP participants showed at least one instance of orthostatic hypotension during assessment.
Juraschek reported comparable baseline characteristics between intensive and standard BP control arms.
Patients who had intensive BP targets had a mean BP of 137.2/75.4 mm Hg when seated, which rose to 140.8/78.5 mm Hg when standing. The standard group had a seated BP of 125.9/69.4 mm Hg and a standing BP of 130.0/72.5 mm Hg.
With a BP goal <130 mm Hg, patients exhibited:
- Higher risk of systolic BP ≤90 mm Hg: OR 3.79 (95% CI 2.35-6.11)
- Higher risk of diastolic BP ≤40 mm Hg: OR 2.42 (95% CI 1.41-4.15)
- Lower risk of systolic BP ≥190 mm Hg: OR 0.40 (95% CI 0.27-0.60)
- Lower risk of diastolic BP ≥110 mm Hg: OR 0.31 (95% CI 0.19-0.50)
However, "the risk of having a SBP [systolic blood pressure] less than 90 was more than three times greater with the intensive treatment goals. That is the key number -- the upright blood pressure, which is what leads to cerebral hypoperfusion and dizziness," commented Benjamin Levine, MD, of the University of Texas Southwestern Medical Center in Dallas.
"Horatio Kaufmann from NYU has shown very nicely that it isn't the change in SBP that is important, but 'how low do you go' when you stand. I remain concerned that the logical, and now documented, risk of a low systolic blood pressure when standing is the natural and expected consequence of more aggressive BP treatment goals," Levine said.
One limitation of SPS3-BP was that it lacked BP measurements in the supine position (as was the case of the other trials), according to Juraschek.
"And using the same parameters for orthostatic hypotension in hypertensive versus normotensive subjects may not be appropriate. Better use a drop of 30 mm Hg in hypertensive folks," Sandroni said.
Stratified analyses by sex and race (among other variables) are forthcoming, Juraschek said during the session Q&A.
Juraschek disclosed no relevant relationships with industry.
Source Reference: Juraschek SP, et al "The effects of lower blood pressure treatment goal on orthostatic hypotension in adults with recent stroke" Hypertension 2019.
Read the original article on Medpage Today: No Added Orthostatic Hypotension With Tighter BP