In this study we chose a broad and explorative approach to study how Tai Chi could affect body functions, health outcomes and how patients with RA experienced Tai Chi. We found that participating in a 12-week Tai Chi group programme improved lower-limb muscle strength and endurance as well as swollen joints at 12 weeks follow-up after the programme. These quantitative physical improvements were reflected by results from the focus group, thus increasing the validity of the findings. Qualitative analyses also identified themes such as desire for further Tai Chi practice, and practical implementation which indicate that Tai Chi can be implemented into daily life of individuals with RA.
Muscle strength and endurance are important aspects of physical functioning for patients with RA. Observed improvement in muscle function of the lower limbs as measured by the Timed-Stands test in this study is supported by patient experience of improved walking ability and more confidence while moving. In patients with RA, Timed-Stands test is highly influenced by disease related factors which affect lower-limb function, such as pain, tender joints, inflammation and weakness [37
]. In our study contributing factors to improvement could be increased strength due to exercising with bended knees and pain reduction, as the participants described increased stability and reduced pain in knee and ankle joints.
In a systematic review, no statistically significant difference between a Tai Chi group and a control group regarding number of swollen joints was reported [26
]. Disease activity in this study was not improved even though swollen joints are integrated into calculation of DAS28. Taken together with potential of bias in our single sample study and with lack of similar results in the qualitative approach we find no convincing evidence that that Tai Chi should decrease disease activity in RA, consistent with our clinical understanding of RA [45
In other reports Tai Chi has lead to reduced pain in patient with osteoarthritis [17
], but not in RA [22
]. In the focus group interview in our study patients reported reduced pain in joints and more vitality, but consistent pain improvement or improvement in other health status measures was not found in the quantitative assessments. Thus, patient experience in our study and popularity of Tai Chi in general indicate positive health effects which are not necessarily picked up by current instruments.
The value of regular physical activity is well documented, both in the management of RA and for secondary disease prevention [4
]. Patients with RA are less physically active than the general population. Physical activity for them needs to be sustainable and enjoyable [48
]. Results from the focus group interview suggest that participating in Tai Chi group exercise contributed to increased confidence in moving and group members supported each other to be physically active and enhanced enjoyment during exercise. Given good compliance, lack of injuries, experience of enhanced physical activity as well as continued practice of Tai Chi during the follow-up indicate that patients with RA increase their level of physical activity when practicing Tai Chi.
Our approach with qualitative research identified additional areas of health benefit not observed in the quantitative assessments. One reason for this might be that two of the physical performance test, SMIS and Walking in a Figure-of-Eight, showed a considerable floor effect. Effects of Tai Chi on stress reduction [11
] and improved balance [13
] have been demonstrated in other studies, but not in patients with RA. It is a conundrum that Tai Chi exercise may have benefits that are not reflected by functional assessment, for example reduced falls in the light of unchanged postural stability [30
]. Such findings lead to a hypothesis that psychosocial factors (e.g. increased confidence) may alter an outcome. In that light our findings of increased confidence in moving and body awareness are supportive, but have otherwise to our knowledge not been addressed before. Further research needs to be done on Tai Chi to validate the results found in this study and, in particular, to study in patients with musculoskeletal disease body control in movement, muscle strength and endurance, as well as aspects of body awareness.
A major limitation in this pilot study is the exploratory single group design with a small number of subjects and the lack of a control group, which make it possible that other factors than the nature of the intervention itself could explain observed changes in outcomes. This was as expected and the constitution of the group was heterogeneous, enhancing exploration of Tai Chi, but also limiting the ability to discover any clear conclusions on the studied phenomenon. Strengths of the study were recruitment of participants from a rheumatology out patient department among correctly classified patients under medical attention for their disease, independent examiners who performed all assessments, an experienced interviewer for the focus group, and competence in analysing quantitative outcomes. Further, to enable thorough exploration, we applied a wide range of measures for assessment of disease activity, performance and health status.
In this study both quantitative and qualitative research methods indicated positive physical health effects of Tai Chi. Psychosocial health effects were most consistently seen in the qualitative analyses. Further research on psychosocial factors with focus on patient experience and patient perspective [49
] will contribute to a broader understanding of Tai Chi.