In This Article
- Affordable non-drug therapies for hypertension are needed to maximize patients' health, limit side effects and control health care costs
- Multiple studies by Massachusetts General Hospital's Division of Hypertension have shown positive results with relaxation response and renal denervation
- Daily practice of relaxation response methods lowers blood pressure and reduces dependence on antihypertensive drugs
- Current research shows that a device for renal denervation successfully lowers blood pressure by disrupting adrenergic innervation of the kidney, with no major adverse events
Research at the Massachusetts General Hospital Corrigan Minehan Heart Center is proving the effectiveness of two non-drug therapies for hypertension: the relaxation response and renal denervation.
"My goal in treating patients, of course, is to reduce their risk of heart attack, stroke, heart failure and kidney disease without any side effects," he says. "But all drugs are potentially associated with side effects. So I'm always looking for non-drug strategies that might be effective. These non-drug approaches are a great resource for patients who are reluctant to take medications, are not responsive to medications or are intolerant of them."
Using the Relaxation Response to Lower Blood Pressure
Herbert Benson, MD, now emeritus director of the Benson-Henry Institute for Mind Body Medicine at Mass General, developed the relaxation response in the 1960s. It involves performing certain techniques daily for 20 minutes that have been associated with a reduction in blood pressure and changes in gene activity.
Other principal investigators in this research include Gregory L. Fricchione, MD, director of the Benson-Henry Institute, John Denninger, MD, PhD, director of research at the Benson-Henry Institute, Jeffery Dusek, PhD, of the Connor Integrative Health Network; and Manoj Bhasin, PhD, and Towia Libermann, PhD, of Beth Israel Deaconess Medical Center.
The goal is to break the train of everyday thought. Techniques vary by individual, but they may include:
- Deep abdominal breathing
- Meditation or yoga
- Progressive muscle relaxation
- Silently repeating one word of the person's choosing (for example, "peace")
- Working on something repetitive, such as knitting
Dr. Benson believed in the method's ability to treat high blood pressure, but his work was largely observational. When he joined Mass General, he sought a partnership with Dr. Zusman to conduct a controlled clinical trial.
"To be perfectly frank, I was skeptical. I did not think this was an effective strategy, but my research nurse was very committed to psychologically-based, alternative strategies for the treatment of not only hypertension, but other clinical disorders. So we did it," Dr. Zusman says. The team went on to prove the effectiveness of the relaxation response for hypertension via two rigorous studies.
The first study, a double-blind, randomized trial, published in 2008 in the Journal of Alternative and Complementary Medicine, evaluated elderly patients who had inadequately controlled blood pressure despite taking multiple medications. The first cohort consisted of patients treated actively with relaxation response; the second cohort received instructions about traditional lifestyle modifications.
"Those who actively participated in relaxation response had a statistically significant and more profound reduction in blood pressure and also were able to reduce their dependence on drugs," Dr. Zusman says.
The second study, also published in the Journal of Alternative and Complementary Medicine in 2018, found that relaxation response could control some patients' blood pressure without drugs.
"The important point was that we did genomic analysis of the changes in gene activity in those who responded to the relaxation response versus non-responders, and the responders demonstrated a decrease in vasoconstrictive genes, a decrease in inflammatory genes, an increase in vasodilator genes and enhanced insulin sensitivity, all of which are highly desirable characteristics for any therapy, pharmacologic or otherwise," Dr. Zusman says.
He encourages primary care providers and cardiologists to consider alternative methods from the beginning: "When you evaluate a patient, instead of thinking immediately, 'Ace inhibitor, beta-blocker, diuretic, calcium antagonist,' think instead, 'Is this a patient who might be amenable, interested and responsive to the relaxation response?'" Examples include very young patients and people who cannot tolerate certain side effects due to their professional roles.
Benson-Henry Institute for Mind Body Medicine offers a 12-week course that teaches the relaxation response technique, covered by most insurance plans.
"This is a very useful adjunct to the other strategies that we employ. And for those who are particularly interested, are committed and are able to achieve the state of the relaxation response, it can be tremendously helpful," Dr. Zusman says. "And it's not just people who are anxious. But you do have to commit because if you don't do it 20 minutes a day, it's not likely to be effective."
Renal Denervation for Hypertension
Additionally, and more recently, Dr. Zusman has been involved in research examining renal denervation to reduce blood pressure.
Renal denervation is a procedure to disrupt adrenergic innervation of the kidney. An interventional cardiologist or interventional radiologist inserts a small, flexible catheter into the artery supplying the kidney. The device delivers energy via ultrasound or other techniques to the wall of the renal artery for several seconds, then is removed. In the hands of a skilled practitioner, Dr. Zusman says, the elective procedure takes about 30 minutes.
A few dozen companies around the world are developing catheters for renal denervation. Dr. Zusman is partnering with Joseph Garasic, MD, director of Mass General's Catheterization Lab and Peripheral Access Intervention Program, to test an ultrasound deneveration system. Studies to date have shown that the device is effective in multiple populations with no major adverse events.
The work done at Mass General is part of an international, multisite effort. The first study, published in The Lancet in 2018, found that renal denervation reduced ambulatory blood pressure at two months without the use of antihypertensive medications. The second study, published in Circulation in 2019, examined patients who had inadequate blood pressure control despite receiving a minimum of three antihypertensive drugs. It found a 6.3 mmHg greater reduction in systolic blood pressure in patients who had renal denervation compared to a sham procedure.
Some of the first patients treated with renal denervation have now had a response for as long as six years, Dr. Zusman says. "So far, no toxicities, no long-term adverse effects, no fibrosis, stenosis, occlusion, deterioration in renal function has been seen as a consequence of the procedure. It's been strikingly safe. It offers a promising option for the future."
Building an Arsenal Against High Blood Pressure
Up to 90% of the population is expected to develop hypertension during the course of their lives, Dr. Zusman says. So it is essential to add non-drug options such as relaxation response and renal denervation to the current arsenal of traditional lifestyle modifications and medications.
"We absolutely need new approaches, cheaper approaches, more effective approaches to the control of blood pressure. Previous attempts to use acupuncture failed, but the techniques above have been shown to be effective," he says. "Non-drug and drug therapies used alone or in combination are critical—or the health care expenditures and effects of hypertension, diabetes and hypercholesterolemia are simply going to overwhelm the developed world."
Learn more about the Hypertension Program at Mass General
Refer a patient to the Corrigan Minehan Heart Center