Background
People with chronic obstructive pulmonary disease (COPD) frequently experience shortness of breath (dyspnoea). Tai Chi is a systematic callisthenic exercise first developed in ancient China that involves a series of slow and rhythmic circular motions. It emphasises use of the 'mind' or concentration to control breathing and circular body motions to facilitate the flow of internal energy (i.e. 'qi') to sustain equilibrium within the body and improve life expectancy. Its effects on balance and muscle strength in the elderly population have been reported, but its effects on dyspnoea, exercise capacity, pulmonary function and psychosocial well-being for people with COPD remain inconclusive. This review explores whether Tai Chi is beneficial for reducing dyspnoea and improving exercise capacity and physiological and psychosocial well-being among people with COPD.
Study characteristics
We included a total of 811 participants from 12 studies in the final analysis of this review. The number of participants in each study ranged from 10 to 206, and mean age ranged from 61 to 74 years. The programme lasted for six weeks to one year. Included studies adopted different styles and numerous forms of Tai Chi. The most commonly reported form is the simplified 24-form Yang-style Tai Chi.
Key results
No unwanted events or side effects were reported throughout the study period. Quality of evidence of all outcomes of interest ranged from very low to moderate. After training was completed, levels of shortness of breath in Tai Chi and control (i.e. usual care) groups were similar. Participants in the Tai Chi group walked farther, by 29.64 metres in six minutes, and had better pulmonary function, than those who received usual care. However, changes in quality of life were not apparent. When the effect of Tai Chi used in addition to another intervention (i.e. breathing exercise or exercise) was examined, we did not find that Tai Chi offered additional benefit in terms of shortness of breath or functional and psychosocial well-being. Currently, only one study has investigated the beneficial effects of Tai Chi on muscle strength and balance; investigators provided insufficient information to allow comment on the data in this review. Future studies addressing these topics are warranted.
No adverse events were reported, implying that Tai Chi is safe to practise in people with COPD. Evidence of very low to moderate quality suggests better functional capacity and pulmonary function in post-programme data for Tai Chi versus usual care. When Tai Chi in addition to other interventions was compared with other interventions alone, Tai Chi did not show superiority and showed no additional effects on symptoms nor on physical and psychosocial function improvement in people with COPD. With the diverse style and number of forms being adopted in different studies, the most beneficial protocol of Tai Chi style and number of forms could not be commented upon. Hence, future studies are warranted to address these topics.
Tai Chi, a systematic callisthenic exercise first developed in ancient China, involves a series of slow and rhythmic circular motions. It emphasises use of 'mind' or concentration to control breathing and circular body motions to facilitate flow of internal energy (i.e. 'qi') within the body. Normal flow of 'qi' is believed to be essential to sustain body homeostasis, ultimately leading to longevity. The effect of Tai Chi on balance and muscle strength in the elderly population has been reported; however, the effect of Tai Chi on dyspnoea, exercise capacity, pulmonary function and psychosocial status among people with chronic obstructive pulmonary disease (COPD) remains unclear.
• To explore the effectiveness of Tai Chi in reducing dyspnoea and improving exercise capacity in people with COPD.
• To determine the influence of Tai Chi on physiological and psychosocial functions among people with COPD.
We searched the Cochrane Airways Group Specialised Register of trials (which included the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Allied and Complementary Medicine Database (AMED) and PsycINFO); handsearched respiratory journals and meeting abstracts; and searched Chinese medical databases including Wanfang Data, Chinese Medical Current Contents (CMCC), Chinese Biomedical Database (CBM), China Journal Net (CJN) and China Medical Academic Conference (CMAC), from inception to September 2015. We checked the reference lists of all primary studies and review articles for relevant additional references.
We included randomised controlled trials (RCTs) comparing Tai Chi (Tai Chi alone or Tai Chi in addition to another intervention) versus control (usual care or another intervention identical to that used in the Tai Chi group) in people with COPD. Two independent review authors screened and selected studies.
Two independent review authors extracted data from included studies and assessed risk of bias on the basis of suggested criteria listed in the Cochrane Handbook for Systematic Reviews of Interventions. We extracted post-programme data and entered them into RevMan software (version 5.3) for data synthesis and analysis.
We included a total of 984 participants from 12 studies (23 references) in this analysis. We included only those involved in Tai Chi and the control group (i.e. 811 participants) in the final analysis. Study sample size ranged from 10 to 206, and mean age ranged from 61 to 74 years. Programmes lasted for six weeks to one year. All included studies were RCTs; three studies used allocation concealment, six reported blinded outcome assessors and three studies adopted an intention-to-treat approach to statistical analysis. No adverse events were reported. Quality of evidence of the outcomes ranged from very low to moderate.
Analysis was split into three comparisons: (1) Tai Chi versus usual care; (2) Tai Chi and breathing exercise versus breathing exercise alone; and (3) Tai Chi and exercise versus exercise alone.
Comparison of Tai Chi versus usual care revealed that Tai Chi demonstrated a longer six-minute walk distance (mean difference (MD) 29.64 metres, 95% confidence interval (CI) 10.52 to 48.77 metres; participants = 318; I2 = 59%) and better pulmonary function (i.e. forced expiratory volume in one second, MD 0.11 L, 95% CI 0.02 to 0.20 L; participants = 258; I2 = 0%) in post-programme data. However, the effects of Tai Chi in reducing dyspnoea level and improving quality of life remain inconclusive. Data are currently insufficient for evaluating the impact of Tai Chi on maximal exercise capacity, balance and muscle strength in people with COPD. Comparison of Tai Chi and other interventions (i.e. breathing exercise or exercise) versus other interventions shows no superiority and no additional effects on symptom improvement nor on physical and psychosocial outcomes with Tai Chi.