August/September 2021 Issue
Mindfulness and Heart Health
By Carrie Dennett, MPH, RDN
Today’s Dietitian
Vol. 23, No. 7, P. 32
Learn how mindfulness-based interventions may lower stress and promote behavior change among patients.
About 655,000 Americans die from heart disease each year, and 805,000 experience a heart attack.1 Stress has long been recognized as a potentially modifiable risk factor for CVD, with epidemiologic data associating chronic stress with a 40% to 50% increase in the occurrence of coronary heart disease (CHD). Indicators of elevated long-term stress, such as social isolation and work-related stress, are associated with poor prognosis among patients with established CHD, and short-term emotional stress can trigger cardiac events in individuals with advanced atherosclerosis.2
Stress increases when demands exceed or overwhelm someone’s psychosocial resources—including social support and personality traits such as optimism and the ability to cope flexibly with challenges—or ability to adapt.2 Back in 2004, INTERHEART, a large, international case-control study designed to assess the importance of risk factors for CHD worldwide, found that after smoking and abnormal lipids, a high psychosocial score that included depression, stress at work or home, financial stress, one or more stressful life events, and an external locus of control was one of the most important risk factors, on par with diabetes and hypertension.3 Despite evidence linking psychological stress and CVD, other risk factors have remained the focus of CVD risk management,2,4 specifically blood pressure, total cholesterol, fasting blood glucose, BMI, smoking, diet, and physical activity.5,6 The American Heart Association recommends dietary patterns that include a variety of fruits and vegetables, whole grains, low-fat dairy products, fish and skinless poultry, nuts, legumes, and nontropical vegetable oils. Two examples of heart-healthy eating patterns are the DASH (Dietary Approaches to Stop Hypertension) eating plan and the traditional Mediterranean diet, although most healthful eating patterns can be adapted to fit this pattern while meeting personal and cultural food preferences.7
One reason stress management is less of a priority than dietary, metabolic, and other health measures is because how stress affects CVD risk has been poorly understood. Other factors include inconsistent results in research on stress and heart disease and uncertainty in determining what approach is most effective.2,4 But a growing body of research is offering evidence that incorporating mindfulness-based interventions can not only mitigate the effects of stress but also provide additional benefits for prevention and treatment of CVD, including enhanced participation in heart-healthy behaviors.
The Stress Response
Stress activates the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, which can lead to increases in hormones—including cortisol—and cytokines that may increase inflammation and raise cholesterol and blood pressure.8
A 2017 study published in The Lancet performed PET/CT scans on adults aged 30 or older without known CVD, then followed them for about three to five years. Of the 293 participants, 22 had at least one cardiovascular event during follow-up. The researchers found significant associations between activity in the amygdala (a brain region involved in stress) and risk of CVD events via a pathway that included increased bone marrow activity—which leads to the release of inflammatory cytokines—and arterial inflammation.9
Amygdalar activity is increased in conditions marked by stress, such as posttraumatic stress disorder, anxiety, and depression. The authors found that individuals with higher resting amygdalar activity experienced CVD events sooner than those with lower resting amygdalar activity. The observed association remained significant even after adjusting for other CVD risk factors.9
A 2016 study published in Circulation saw results that could be attributed to positive effects on the brain-to-bone marrow pathway. The study randomized 151 outpatients aged 36 to 84 with stable CHD to 12 weeks of comprehensive cardiac rehabilitation with or without stress management training. Cardiac rehabilitation typically includes physical activity, medical management of blood pressure and lipids, nutrition counseling, and smoking cessation. The stress management training combined education, group support, and cognitive behavioral therapy, with a focus on strategies for reducing demands and increasing coping abilities. The patients who received both components experienced greater reductions in stress levels—including decreases in anxiety, depression, and perceived stress—and about 50% fewer clinical events compared with the cardiac rehabilitation–only group.4
Stress also may have an indirect effect on CVD risk by influencing whether people engage in health behaviors such as physical activity, following recommended medical treatments, and avoiding risky behaviors such as smoking, excessive alcohol intake, substance use, or consumption of highly processed foods. While a “heart-healthy” glass of red wine may help reduce stress, there may be a better option. A growing body of research suggests that mindfulness-based interventions may address both direct and indirect stress-related mechanisms, affecting multiple CVD risk factors.
What Is Mindfulness?
Jon Kabat-Zinn, PhD, professor emeritus of medicine and the creator of the Stress Reduction Clinic and the Center for Mindfulness in Medicine, Health Care, and Society at the University of Massachusetts Medical School, has famously defined mindfulness as “paying attention, on purpose, in the present moment, nonjudgmentally.”
Dispositional mindfulness—the ability to attend in a nonjudgmental way to one’s own physical and mental processes during ordinary, everyday tasks—may be connected to cardiovascular health, possibly because mindful people have a greater awareness, and thus more control over, their behaviors and situations that trigger those behaviors. A cross-sectional study of 382 US adults in 2015 found that those with high dispositional mindfulness levels were 86% more likely to have good cardiovascular health compared with those who had low dispositional mindfulness.10
According to the study, led by Eric Loucks, PhD, an associate professor of epidemiology, behavioral and social sciences, and medicine at Brown University, and director of the Mindfulness Center at Brown, dispositional mindfulness is an inherent trait influenced by genetic and environmental factors, but it also can be modified.10 That’s good news, because a research review Loucks coauthored that year found that mindfulness may have a positive effect on physical activity, smoking cessation, diet, weight, blood pressure, and diabetes regulation.11 Mindfulness may help promote healthful lifestyle behaviors by improving self-regulation through the following:
• Enhanced attention control: increased awareness of experiences related to CVD risk factors, such as smoking, diet, physical activity, and medication adherence, helping to highlight the short- and long-term effects.
• Self-awareness: awareness of and self-reflection on thoughts and feelings, ability to step back from emotional reactivity, clarification of values, and awareness of physical sensations related to CVD risk factors, such as feeling good when eating healthful, palatable foods and engaging in physical activity.
• Emotion regulation: improved stress response, self-efficacy, self-kindness, self-compassion, and skills to manage cravings for cigarettes, palatable foods, and sedentary activities.11
“Our research is showing that interoceptive awareness—in other words, self-awareness—is important, particularly for diet change,” Loucks says regarding the studies coming out of his Mindfulness and Cardiovascular Health Lab. “It seems that through learning mindfulness and directing it to their diet, participants are becoming more aware of how different types of food make them feel, and then using their skills in attention control to direct their attention towards healthier food choices.”
There are many ways to practice mindfulness, but are they all equally valid for protecting heart health? Most cardiac-focused mindfulness-based interventions use, or are derived from, Mindfulness-Based Stress Reduction (MBSR).12
MBSR and Mindfulness Meditation
Kabat-Zinn began developing MBSR, the first mindfulness-based intervention, in 1977.13 MBSR integrates mindfulness meditation, other contemplative practices such as yoga, and modern psychological theories about stress and stress management for use in health care settings.
Mindfulness meditation involves paying attention to present-moment experiences—which may include strong emotions, difficult thoughts, or unpleasant sensations—with an orientation of curiosity, openness, acceptance, nonreactivity, and nonjudgment. Several types of mindfulness meditation are taught in mindfulness-based interventions, including focused attention, which involves directing attention on an object and returning attention to the object when the mind wanders, and open monitoring, which includes being aware of thoughts, emotions, and sensations without reacting to them. Reducing anxiety, depression, and stress through mindfulness meditation may support better chronic disease self-management.14
A 2017 scientific statement from the American Heart Association says, “Neurophysiological and neuroanatomical studies demonstrate that meditation can have long-standing effects on the brain, which provide some biological plausibility for beneficial consequences on the physiological basal state and on cardiovascular risk.”15 The authors conclude that studies of meditation suggest a possible benefit on cardiovascular risk, although the overall quality and, in some cases, quantity of study data are modest. They also surmise that because meditation instruction and practice is widely accessible, inexpensive, and low risk, meditation can be considered as an adjunct to traditional cardiovascular risk reduction therapies for patients who have interest.
CVD-Specific Interventions
Not all mindfulness and CVD research uses cardiac-focused interventions, however, and that may matter. A 2014 systematic review and meta-analysis found little to no effect of mindfulness-based interventions on blood pressure in patients with hypertension, but notes that the interventions used in the studies weren’t focused on cardiovascular
health—they applied solely to stress reduction or depression.16
Loucks was the lead developer of the MBSR-derived Mindfulness-Based Blood Pressure Reduction (MB-BP) program, designed to help participants increase their ability to self-regulate and then direct these mindfulness skills towards modifiable determinants of blood pressure. A 2019 stage 1 clinical trial enrolled 48 participants with hypertension or prehypertension and no current meditation practice. A qualified MBSR instructor with expertise in CVD taught the eight-week course. Participants attended weekly 2.5-hour group sessions and one daylong retreat. They learned a range of mindfulness skills similar to MBSR, including body scan exercises, meditation, and yoga, and discussed stress and coping. Participants were asked to practice mindfulness skills 45 minutes per day, six days per week.17
Unlike MBSR, the MB-BP program includes education on hypertension risk factors and health effects, as well as specific mindfulness modules focused on awareness of diet, physical activity, medication adherence, alcohol consumption, stress, and social support for behavior change. Overall, participants improved adherence to several of these determinants, including engaging in physical activity, following a DASH-consistent diet, and limiting alcohol consumption. They also saw an average 6.1-mm Hg reduction in systolic blood pressure at one year follow-up, with the most pronounced effects (a 15.1-mm Hg reduction) in participants with stage 2 uncontrolled hypertension (systolic blood pressure at or above 140 mm Hg).17
A follow-up 2020 qualitative study explored how MB-BP participants felt the program improved their cardiovascular health. Participants said that breath and body awareness were the two mindfulness practices used the most in their daily lives. For example, they might use these practices to perceive tension or an accelerated heart rate in their body and then breathe to calm themselves. They also used these practices to ground themselves in the moment, allowing them to regulate their emotions, helping them respond rather than react to stressful situations, and use self-kindness rather than self-judgment, and avoid ruminating on difficulties. Increased emotional regulation also helped participants make more healthful dietary choices and notice how their body felt when choosing certain foods over others.18
A 2020 systematic review and meta-analysis in Annals of Behavioral Medicine examined the effects of mindfulness-based interventions on psychological (anxiety and depression) and physiological (blood pressure) measures in 1,476 adults with CVD or who had experienced a cardiac event. Compared with controls, participants who received a mindfulness-based intervention reported greater improvement of symptoms of anxiety and depression, as well as perceived stress and overall distress. Measures of systolic, but not diastolic, blood pressure also improved in the intervention groups.19
A small 2021 pilot study randomized 19 older adults (average age 67) with metabolic syndrome and either an exaggerated or a blunted response to stress to a nine-week MBSR course or a wait-list control group. Metabolic syndrome affects 40% of adults older than 60 and doubles the risk of developing CVD. Patients who completed the MBSR course reported increased relaxation, greater interpersonal connection, and improved body awareness. They also experienced a 15% decrease in LDL cholesterol and 10% decrease in total cholesterol, compared with 4.5% and 1%, respectively, in the control group.20
One open question is, what happens when the mindfulness-based intervention is over? Do observed benefits persist? A 2019 pilot trial at the University of Minnesota randomized cardiac patients to an eight-week MBSR program or to usual care. At three months, MBSR patients showed improvements in depression, anxiety, and health-related quality of life, as well as greater improvement or less worsening of most CVD risk factors. However, there was an attenuation of treatment effects at nine months. The authors say that a booster dose of MBSR may be needed for a persistent effect.21
In an interview for the National Institutes of Health’s Science of Behavior Change Network, Loucks says graduates of his MB-BP program have continued access to twice-monthly community groups and other resources, but only about 20% of participants use them—possibly because they don’t need them.22
“I think it’s a bit like riding a bike, where once you learn how, you always know how. But, if you keep practicing riding, you will get faster and better at it,” Loucks says. “Our research findings showed that the amount of home mindfulness practice done during the MB-BP course still predicted blood pressure one year later, regardless of how much people practiced in the interim. However, at least personally, I know that if I don’t meditate for two to three days, my ability to self-regulate my diet and physical activity worsens.”
However, Loucks notes there’s still more to learn, not just about the efficacy of mindfulness-based interventions but also about their longevity. “I’d like to see methodologically rigorous randomized controlled trials with longer-term follow-up, using approaches that are likely to be scalable in populations,” he says.
Bringing Mindfulness Into the Dietitian’s Office
Sustained behavior change can be challenging, and the specter of chronic disease or its complications motivates some patients—but causes others to stick their heads in the sand. Incorporating aspects of mindfulness—awareness, nonjudgment, and staying in the present rather than ruminating on the past or trying to forecast the future—can help patients attend to things they need to do for their cardiovascular health, including following nutrition recommendations. Mindfulness can help patients better handle cravings without necessarily acting on them and be less reactive to uncomfortable emotions, which could reduce emotional eating. Introducing the idea of nonjudgment may help facilitate trust.
RDs with a strong interest in clinical applications of mindfulness and who have a personal mindfulness meditation practice certainly can pursue MBSR teacher training. However, less intensive options include knowing what mindfulness-based interventions are available locally, especially those with a focus on reducing CVD risk. If patients are highly motivated, there are online versions of MBSR programs, and Kabat-Zinn’s book, Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain, and Illness, is based on MBSR and contains a complete eight-week program.
Loucks’ first book, The Mindful College Student: Essential Skills to Help You Succeed, Boost Well-Being, and Build the Life You Want, will be published next year by New Harbinger Press. “It teaches many of the skills for mindfulness applied to physical and mental well-being tested in our clinical trials, and, while geared towards young adults, it is accessible by anyone.”
— Carrie Dennett, MPH, RDN, is the nutrition columnist for The Seattle Times, owner of Nutrition by Carrie, and author of Healthy for Your Life: A Holistic Guide to Optimal Wellness.
References
1. Heart disease facts. Centers for Disease Control and Prevention website. https://www.cdc.gov/heartdisease/facts.htm. Updated September 8, 2020.
2. Steptoe A, Kivimäki M. Stress and cardiovascular disease. Nat Rev Cardiol. 2012;9(6):360-370.
3. Yusuf S, Hawken S, Ounpuu S, et al. Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study. Lancet. 2004;364(9438):937-952.
4. Blumenthal JA, Sherwood A, Smith PJ, et al. Enhancing cardiac rehabilitation with stress management training: a randomized, clinical efficacy trial. Circulation. 2016;133(14):1341-1350.
5. My Life Check | Life's Simple 7. American Heart Association website. https://www.heart.org/en/healthy-living/healthy-lifestyle/my-life-check--lifes-simple-7. Updated May 2, 2018.
6. Lloyd-Jones DM, Hong Y, Labarthe D, et al. Defining and setting national goals for cardiovascular health promotion and disease reduction: the American Heart Association's strategic Impact Goal through 2020 and beyond. Circulation. 2010;121(4):586-613.
7. The American Heart Association diet and lifestyle recommendations. The American Heart Association website. https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/nutrition-basics/aha-diet-and-lifestyle-recommendations. Updated August 15, 2017.
8. Brotman DJ, Golden SH, Wittstein IS. The cardiovascular toll of stress. Lancet. 2007;370(9592):1089-1100.
9. Tawakol A, Ishai A, Takx RA, et al. Relation between resting amygdalar activity and cardiovascular events: a longitudinal and cohort study. Lancet. 2017;389(10071):834-845.
10. Loucks EB, Britton WB, Howe CJ, Eaton CB, Buka SL. Positive associations of dispositional mindfulness with cardiovascular health: the New England Family Study. Int J Behav Med. 2015;22(4):540-550.
11. Loucks EB, Schuman-Olivier Z, Britton WB, et al. Mindfulness and cardiovascular disease risk: state of the evidence, plausible mechanisms, and theoretical framework. Curr Cardiol Rep. 2015;17(12):112.
12. Crane RS, Brewer J, Feldman C, et al. What defines mindfulness-based programs? The warp and the weft. Psychol Med. 2017;47(6):990-999.
13. Kabat-Zinn J. Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain and Illness. Revised edition. Bantam Press; 2013.
14. Schuman-Olivier Z, Trombka M, Lovas DA, et al. Mindfulness and behavior change. Harv Rev Psychiatry. 2020;28(6):371-394.
15. Levine GN, Lange RA, Bairey-Merz CN, et al. Meditation and cardiovascular risk reduction: a scientific statement from the American Heart Association. J Am Heart Assoc. 2017;6(10):e002218.
16. Abbott RA, Whear R, Rodgers LR, Bethel A, Thompson Coon J, Kuyken W, Stein K, Dickens C. Effectiveness of mindfulness-based stress reduction and mindfulness-based cognitive therapy in vascular disease: a systematic review and meta-analysis of randomised controlled trials. J Psychosom Res. 2014;76(5):341-351.
17. Loucks EB, Nardi WR, Gutman R, et al. Mindfulness-based blood pressure reduction (MB-BP): stage 1 single-arm clinical trial. PLoS One. 2019;14(11):e0223095.
18. Nardi WR, Harrison A, Saadeh FB, Webb J, Wentz AE, Loucks EB. Mindfulness and cardiovascular health: qualitative findings on mechanisms from the mindfulness-based blood pressure reduction (MB-BP) study. PLoS One. 2020;15(9):e0239533.
19. Scott-Sheldon LAJ, Gathright EC, Donahue ML, et al. Mindfulness-based interventions for adults with cardiovascular disease: a systematic review and meta-analysis. Ann Behav Med. 2020;54(1):67-73.
20. Gentile C, Starnino L, Dupuis G, D'Antono B. Mindfulness-based stress reduction in older adults at risk for coronary artery disease: a pilot randomized trial [published online March 15, 2021]. Clin Gerontol. doi: 10.1080/07317115.2021.1887421.
21. Nijjar PS, Connett JE, Lindquist R, et al. Randomized trial of mindfulness-based stress reduction in cardiac patients eligible for cardiac rehabilitation. Sci Rep. 2019;9(1):18415.
22. SOBC spotlight: interview with Eric Loucks, PhD. Science of Behavior Change website. https://scienceofbehaviorchange.org/sobc-spotlight-interview-with-eric-loucks-phd/