YOGA FOR ANXIETY AND DEPRESSION
Harvard Mental Health Letter, April 2009
Taming the stress response
By reducing perceived stress and anxiety, yoga appears to modulate stress response systems. This, in turn, decreases physiological arousal — for example, reducing the heart rate, lowering blood pressure, and easing respiration. There is also evidence that yoga practices help increase heart rate variability, an indicator of the body’s ability to respond to stress more flexibly.
A small but intriguing study further characterizes the effect of yoga on the stress response. In 2008, researchers at the University of Utah presented preliminary results from a study of varied participants’ responses to pain. They note that people who have a poorly regulated response to stress are also more sensitive to pain. Their subjects were 12 experienced yoga practitioners, 14 people with fibromyalgia (a condition many researchers consider a stress-related illness that is characterized by hypersensitivity to pain), and 16 healthy volunteers.
When the three groups were subjected to more or less painful thumbnail pressure, the participants with fibromyalgia — as expected — perceived pain at lower pressure levels compared with the other subjects. Functional MRIs showed they also had the greatest activity in areas of the brain associated with the pain response. In contrast, the yoga practitioners had the highest pain tolerance and lowest pain-related brain activity during the MRI. The study underscores the value of techniques, such as yoga, that can help a person regulate their stress and, therefore, pain responses.
Improved mood and functioning
Questions remain about exactly how yoga works to improve mood, but preliminary evidence suggests its benefit is similar to that of exercise and relaxation techniques.
In a German study published in 2005, 24 women who described themselves as “emotionally distressed” took two 90-minute yoga classes a week for three months. Women in a control group maintained their normal activities and were asked not to begin an exercise or stress-reduction program during the study period.
Though not formally diagnosed with depression, all participants had experienced emotional distress for at least half of the previous 90 days. They were also one standard deviation above the population norm in scores for perceived stress (measured by the Cohen Perceived Stress Scale), anxiety (measured using the Spielberger State-Trait Anxiety Inventory), and depression (scored with the Profile of Mood States and the Center for Epidemiological Studies Depression Scale, or CES-D).
At the end of three months, women in the yoga group reported improvements in perceived stress, depression, anxiety, energy, fatigue, and well-being. Depression scores improved by 50%, anxiety scores by 30%, and overall well-being scores by 65%. Initial complaints of headaches, back pain, and poor sleep quality also resolved much more often in the yoga group than in the control group.
One uncontrolled, descriptive 2005 study examined the effects of a single yoga class for inpatients at a New Hampshire psychiatric hospital. The 113 participants included patients with bipolar disorder, major depression, and schizophrenia. After the class, average levels of tension, anxiety, depression, anger, hostility, and fatigue dropped significantly, as measured by the Profile of Mood States, a standard 65-item questionnaire that participants answered on their own before and after the class. Patients who chose to participate in additional classes experienced similar short-term positive effects.
Further controlled trials of yoga practice have demonstrated improvements in mood and quality of life for the elderly, people caring for patients with dementia, breast cancer survivors, and patients with epilepsy.
Potential help for PTSD
Since evidence suggests that yoga can tone down maladaptive nervous system arousal, researchers are exploring whether or not yoga can be a helpful practice for patients with post-traumatic stress disorder (PTSD).
One randomized controlled study examined the effects of yoga and a breathing program in disabled Australian Vietnam veterans diagnosed with severe PTSD. The veterans were heavy daily drinkers, and all were taking at least one antidepressant. The five-day course included breathing techniques (see above), yoga asanas, education about stress reduction, and guided meditation. Participants were evaluated at the beginning of the study using the Clinician Administered PTSD Scale (CAPS), which ranks symptom severity on an 80-point scale.
Six weeks after the study began, the yoga and breathing group had dropped their CAPS scores from averages of 57 (moderate to severe symptoms) to 42 (mild to moderate). These improvements persisted at a six-month follow-up. The control group, consisting of veterans on a waiting list, showed no improvement.
About 20% of war veterans who served in Afghanistan or Iraq suffer from PTSD, according to one estimate. Experts treating this population suggest that yoga can be a useful addition to the treatment program.
Researchers at the Walter Reed Army Medical Center in Washington, D.C., are offering a yogic method of deep relaxation to veterans returning from combat in Iraq and Afghanistan. Dr. Kristie Gore, a psychologist at Walter Reed, says the military hopes that yoga-based treatments will be more acceptable to the soldiers and less stigmatizing than traditional psychotherapy. The center now uses yoga and yogic relaxation in post-deployment PTSD awareness courses, and plans to conduct a controlled trial of their effectiveness in the future.
Cautions and encouragement
Although many forms of yoga practice are safe, some are strenuous and may not be appropriate for everyone. In particular, elderly patients or those with mobility problems may want to check first with a clinician before choosing yoga as a treatment option.
But for many patients dealing with depression, anxiety, or stress, yoga may be a very appealing way to better manage symptoms. Indeed, the scientific study of yoga demonstrates that mental and physical health are not just closely allied, but are essentially equivalent. The evidence is growing that yoga practice is a relatively low-risk, high-yield approach to improving overall health.
OTHER RESEARCH RESULTS:
– In 2010, Aetna partnered with Duke University’s School of Medicine and found that regular yoga substantially decreased stress levels and health care costs. Following this, CEO Mark Bertolini made yoga available to all Aetna employees nationwide.
– According to the World Health Organization, the cost of stress to American businesses is as high as $300 billion. And unless we change course, this will only get worse. Over the last 30 years, self-reported levels of stress have increased 18 percent for women and 25 percent for men.
– Business professors Michael Porter, Elizabeth Teisberg, and Scott Wallace wrote in the HBS Working Knowledge, studies show that U.S. employers spend 200 to 300 percent more for the indirect costs of health care — in the form of absenteeism, sick days, and lower productivity — than they do on actual health care payments. Their recommendation: that companies “mount an aggressive approach to wellness, prevention, screening and active management of chronic conditions.”
– Mark Williams, professor of clinical psychology at Oxford ad an expert in mindfulness-based cognitive therapy conducted a nine week mindfulness training after which participants had “an increased sense of purpose and fewer feelings of isolation and alienation, along with decreased symptoms of illness as diverse as headaches, chest pain, congestion and weakness.”
– An National Institutes of Health study on meditation showed a 23 percent decrease in mortality, a 30 percent decrease in death due to cardiovascular problems and a big decrease in cancer mortality as well.