A mixed methods study of Tai Chi exercise for patients with chronic heart failure aged 70 years and older.

Only 45 of 191 invited patients agreed to participate, which markedly reduced power. Drop-out was unequal: in the training group 20 of 25 and 21 of 25 completed the two follow-up tests, while in the control group 14 of 20 and 12 of 20 completed them. The authors could not adjust for baseline differences between completers and drop-outs because the sample was too small. At baseline, the control group rated higher mental fatigue and had higher BMI than the training group. The study did not ask non-participants or drop-outs for reasons, although some gave health problems, travel, weather, language or competing activities. Only ten training-group participants were interviewed, and the authors note that those who agreed may have had more positive experiences. Participants had no previous Tai Chi experience and were not asked about expectations at baseline. The authors state the small sample means findings may have occurred at random. The authors question the choice of outcome variables for older patients with chronic heart failure.

Do not conclude that Tai Chi improves fatigue, quality of life, physical performance or NTproBNP in older heart failure patients. The between-group differences were not statistically significant, the study was underpowered, and the positive reports came from interviews about experience rather than measured outcomes.