A program of regular tai chi exercises improved measures of quality of life in patients with chronic heart failure but failed to improve more conventional measures of exercise efficacy, compared with patients who only received education.
"Tai chi exercise, a multicomponent mind-body training modality that is safe and has good rates of adherence, may provide value in improving daily exercise, quality of life, self-efficacy, and mood in frail, deconditioned patients with systolic HF. A more restricted focus on traditional measured exercise capacity may underestimate the potential benefits of integrated interventions such as tai chi," wrote Dr. Gloria Y. Yeh and her coinvestigators in a study released April 25 in the Archives of Internal Medicine.
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Despite improvements in quality of life indicators, no significant changes were seen in serum biomarkers, which included B-type natriuretic peptide, catecholamines, and C-reactive protein among adults performing tai chi.
Tai chi is a gentle, meditative exercise of flowing circular movements, balance and weight shifting, breathing techniques, visualization, and focused internal awareness. "Tai chi may represent an additional exercise option for patients with HF because it integrates multiple relevant processes, including mild to moderate aerobic activity, upper and lower extremity training, and core strengthening," they said.
The researchers recruited 100 heart failure patients with a left ventricular ejection fraction of 40% or lower in the past 2 years, a stable medical regimen, and New York Heart Association class I-III from Boston medical practices.
They were randomly assigned to receive a 12-week tai chi exercise program or a heart health education program (attention control). All participants continued to receive usual care, noted Dr. Yeh, assistant professor of medicine at Beth Israel Deaconess and in the division for research and education in complementary and integrative medical therapies at Harvard Medical School, both in Boston, and her associates.
All assessments were performed at baseline and at 12 weeks. Patients performed a symptom-limited exercise test using a bicycle ramp protocol to determine peak oxygen uptake, a 6-minute walk test, and a Timed Up and Go functional assessment.
The researchers used the Minnesota Living with Heart Failure Questionnaire (MLHFQ) to assess disease-specific quality of life, the Profile of Mood States to assess emotional states expected to respond to clinical intervention, and the Cardiac Exercise Self-Efficacy Instrument to assess patient confidence in performing exercise-related activities.
The tai chi intervention consisted of 1-hour group classes held twice weekly for 12 weeks by certified instructors. Patients were encouraged to practice at home at least three times a week. Patients in the control group attended nurse practitioner–led education sessions twice weekly and were asked not to start tai chi during the study period.
The mean age of study participants was 67 years, the mean baseline LVEF was 29%, and the median NYHA class was II. Most patients were receiving beta-blockers (86%) and ACE inhibitors (85%).
At 12 weeks, significant improvements were seen in scores on the MLHFQ, Profile of Mood States (total mood disturbance, depression, and vigor subscales), and Cardiac Exercise Self-Efficacy Instrument in the tai chi group, compared with the heart health education group. There were no significant changes in serum biomarkers, which included B-type natriuretic peptide, catecholamines, and C-reactive protein, Dr. Yeh and her associates reported (Arch. Intern. Med. 2011;171:750-7).
Post hoc exploratory analyses pointed to subsets of patients who derived significant benefits from tai chi, compared with education only. Tai chi patients without implanted cardioverter defibrillators devices, those with NYHA class II and III symptoms, and those with a nonischemic etiology of HF improved significantly on the MLHFQ, compared with education-only patients. The researchers also found that participants with a higher baseline resting heart rate had greater improvements in the MLHFQ score in the tai chi group; there was no association in the control group.
"One of the purported mechanisms of mind-body exercises, such as tai chi, is favorable modulation of the autonomic nervous system. In our post hoc analyses, we found that, in participants with higher resting heart rates (and presumably more sympathetic nervous system ‘overdrive’), there was a greater benefit with tai chi," the investigators noted.
At the 6-month follow-up telephone contact, 34 patients in the tai chi group (68.0%) reported continued practice (including daily, weekly, and monthly). There were no adverse events related to the protocol.
Dr. Yeh and her associates reported no significant financial relationships.