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.
Benefits of controlled breathing
A type of controlled breathing with roots in traditional yoga shows promise in providing relief for depression. The program, called Sudarshan Kriya yoga (SKY), involves several types of cyclical breathing patterns, ranging from slow and calming to rapid and stimulating.
One study compared 30 minutes of SKY breathing, done six days a week, to bilateral electroconvulsive therapy and the tricyclic antidepressant imipramine in 45 people hospitalized for depression. After four weeks of treatment, 93% of those receiving electroconvulsive therapy, 73% of those taking imipramine, and 67% of those using the breathing technique had achieved remission.
Another study examined the effects of SKY on depressive symptoms in 60 alcohol-dependent men. After a week of a standard detoxification program at a mental health center in Bangalore, India, participants were randomly assigned to two weeks of SKY or a standard alcoholism treatment control. After the full three weeks, scores on a standard depression inventory dropped 75% in the SKY group, as compared with 60% in the standard treatment group. Levels of two stress hormones, cortisol and corticotropin, also dropped in the SKY group, but not in the control group. The authors suggest that SKY might be a beneficial treatment for depression in the early stages of recovery from alcoholism.
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.
. Delirium, dementia, amnestic, and other cognitive disorders. Cognitive disorders involve a clinically significant deficit in cognition or memory that represents a marked change from a previous level of functioning. The disorders are usually further categorized based on their presumed etiology.
• A delirium is characterized by a disturbance in consciousness and a change in cognition that develop over a short time. Some examples are delirium due to a medical condition, and substance-induced delirium (such as caused by a drug of abuse or a toxin). Drugs that are listed as causing the condition include alcohol, amphetamines, caffeine, cocaine, hallucinogens, inhalants, marijuana, nicotine, opiates, phencyclidine (PCP), sedatives, and other unspecified chemicals. Substance withdrawal may also produce a delirium.
• A dementia is characterized by multiple cognitive deficits that include memory impairment. Examples are dementia of Alzheimer's type, vascular dementia, and dementia due to HIV disease.
• An amnestic disorder is shown by multiple cognitive deficits that include memory impairment, but the disorder is not connected with states of delerium or dementia. A major problem is the transfer of information from short term to long term memory. Amnestic disorders result from a physical cause such as a traumatic event (for example, a head injury incurred in an accident, during surgery, or from an electric shock), drug abuse, or the use of medications.
• A fourth category, cognitive disorder not otherwise specified, is used to delineate a cognitive dysfunction presumed to be due to a general medical condition or substance use but that does not meet the other diagnostic criteria.
A Report By