SPRINT: Benefits of intensive BP lowering may be lost quickly if treatment not sustained
Click Here to Manage Email Alerts
The benefits of intensive BP treatment on CV death and all-cause mortality observed in the SPRINT trial did not persist beyond the conclusion of the trial intervention, researchers reported.
At 10 years, the mean systolic BP among those assigned to the intensive treatment group was not significantly different compared with those assigned to a standard BP target, according to the long-term results of the SPRINT trial published in JAMA Cardiology.
“Findings from our ancillary study of outpatient [systolic] BP measured in routine clinical practice indicated that the difference in [systolic] BP between treatment groups diminished steadily over time, with no detectable difference in [systolic] BP approximately 9 years after randomization,” Byron C. Jaeger, PhD, assistant professor of biostatistics and data science at Wake Forest University School of Medicine, and colleagues wrote. “These results, in combination with the primary findings of the trial, indicate that the beneficial effect of intensive treatment among adults with hypertension appears to diminish quickly if intensive BP control is not sustained.”
As Healio previously reported, an aggressive systolic BP target of less than 120 mm Hg was associated with lower rates of the primary composite outcome of MI, other ACS, stroke, HF and death from CV causes, in addition to lower all-cause mortality, compared with a standard target of systolic BP less than 140 mm Hg.
For the present secondary analysis, researchers evaluated the 4.5 years occurrence of CV death and all-cause mortality among participants in the SPRINT cohort using outpatient electronic health record data (mean age, 67.9 years; 35.6% women; 31.5% Black).
Long-term CV and all-cause death in SPRINT
The intervention phase of SPRINT occurred between Nov. 8, 2010, and Aug. 20, 2015.
The current study includes part of the trial phase and additional follow-up through July 1, 2016, and observational follow-up that continued through December 2020.
Total median follow-up time was 8.8 years for both treatment arms.
During the trial phase of SPRINT, risk for all-cause mortality in the intensive treatment arm was lower compared with the standard treatment arm (HR = 0.83; 95% CI, 0.68-1.01); however, the benefit of intensive treatment did not persist and was attenuated at 2.8 years following trial randomization (HR = 1.08; 95% CI, 0.94-1.23).
Results were similar for the outcome of CV death, where the benefits of intensive treatment compared with standard care during the trial period (HR = 0.66; 95% CI, 0.49-0.89) were attenuated at 5.6 years during the observational phase (HR = 1.02; 95% CI, 0.84-1.24).
After performing a subgroup analysis of 2,944 participants with a median of 20 outpatient BP measurements during the observational phase, researchers observed a mean between-group difference in systolic BP of 0.21 mm Hg at 10 years (95% CI, 3.6 to 3.2). The mean systolic BP in the intensive treatment group rose from 132.8 mm Hg at 5 years to 140.4 mm Hg at 10 years.
“A lingering question from this study is what were the primary drivers of the increase in BP in the intensive treatment group following the trial,” the researchers wrote. “Unfortunately, as part of the [electronic health record] ancillary study, we only have access to medication data in the Veterans Affairs system and do not have information about who participants had encounters with, and so our ability to inform this question is quite limited. We believe this will be an important topic for future research in trials such as the STEP trial and other ongoing trials investigating more intensive BP control.”
Standard approaches ‘fail to achieve ideal BP control’
In a related editorial, Daniel W. Jones, MD, director of clinical and population sciences at the Mississippi Center for Obesity Research at the University of Mississippi School of Medicine, and colleagues discussed how clinical practice must shift to better improve BP control to a degree seen during the SPRINT trial.
“The SPRINT study participants were older with a history of atherosclerotic disease or at high risk. Once blood vessels and organs are damaged from years of hypertension and other risk factors, BP management and control become more challenging,” the authors wrote. “The vigorous controlled strategies used in the SPRINT study were able to overcome this challenge. However, contemporary clinical practice strategies seem less likely to do so.
“There is good evidence to reform our systems to mimic rigorous management strategies used in clinical trials proven to provide better BP control rates than traditional approaches,” the authors wrote. “Telehealth strategies are another promising area that can improve upon the intermittent, reactive and time-consuming process of in-person clinic visits. It is time to acknowledge that standard approaches to BP management in clinical practice in the United States are failing to achieve ideal BP control rates.”
Reference:
Perspective
Back to Top
There were two things that I was struck by. One was the fact that people's BPs gradually returned in the two groups to virtually identical values. That points out the difficulty outside of clinical trials of aggressive BP control.
In the general population, a minority of hypertensive patients are controlled for any one of a number of reasons, including noncompliance, poor dietary habits, lack of exercise, concomitant medications and all the problems that we face in adequate BP control. In patients who participate in clinical trials, we have generally a motivated patient population and they tend to be compliant, and they do tend to take their medications as prescribed. But in this study, we see exactly what happens. You've got a group of motivated patients, highly compliant, participating in the study, but then when they're not closely monitored by the study staff, their behavior goes back to that of the general population. Perhaps their diets aren't as good as we would like with regard to salt intake. Perhaps their weight creeps up. Perhaps, and most likely, they're not as compliant with their medications. They perhaps aren't seen as often to have their medications modified, and their BPs go up progressively.
The second thing was that in association with these rises in BP, mortality and morbidity returns to that of those whose BP have not been aggressively or intensively controlled. That just points out that we really need to be continuously vigilant in controlling patients’ BPs, because the benefits of BP control can be quickly lost if the BP drifts back to poorly controlled values.
One of the important messages would be the importance of patient participation in their own BP control. This is especially true in the pandemic era, because people aren't being seen face-to-face as often. I encourage patients to monitor their own BP. I encourage everybody to have a BP monitor. I encourage them to bring it in with them when they see me so we can corroborate that they're taking their BP appropriately and that their device is working appropriately. And I encourage them to regularly monitor their BP values, and if their BP should go up that they be in contact with me so we can either make a mid-course correction during a virtual visit or have a face-to-face visit when I can measure their BP personally and decide whether there needs to be a change in their medication regimen or if there's been some reason that their BP has risen since their last evaluation. That has worked reasonably well for the majority of my patients who either personally can — or have a family member who can — measure their BP on a regular basis. That doesn't mean they have to measure it twice per day every day of the week. But measuring BP in the morning and the afternoon 1 or 2 days a week or occasionally during the month, especially in those who are very well controlled, can give us a very accurate picture of their BP values.
We have over 200 medications for the treatment of high BP. We have nondrug therapies, including relaxation response, which has been shown to be effective in a significant number of patients. There are a number of new drugs that are being developed, and there are a number of new procedures being developed that might provide mechanisms by which we control patients’ BPs. There's no reason a patient has to suffer with side effects in order to adequately control their BP values, given all of these options. In an appropriate partnership between the patient and his or her physician, it will be possible to control their BP to some of these intensively controlled values and in so doing, reduce their CV risk.
Collapse
Read more about
Click Here to Manage Email Alerts