Research in Focus: Tai Chi vs Health Education in Subsidized Housing

  •   January 9, 2020
  •  Leanne Loranger, PT

Full Citation: Lipsitz LA, Macklin EA, Travison TG, Manor B, Gagnon P, Tsai T, Aizpurua II, Lo OY, Wayne PM. A Cluster Randomized Trial of Tai Chi vs Health Education in Subsidized Housing: The MI-WiSH Study. Journal of the American Geriatrics Society, 2019; 67:1812-1819.

Background

Exercise is commonly recommended as an intervention to reduce the risk of the development of chronic health conditions and of morbidity from those conditions.2 Tai chi is an exercise approach that has been recommended for many years for older adults, including individuals with a variety of disabilities and diseases. Several studies have demonstrated multiple benefits of tai chi with this population. However, these studies have not typically included older adults living in subsidized housing who may face unique health challenges and risks of decline due to their socio-economic status. This study specifically targeted this patient population and compared the effect of tai chi versus health education on physical function, health-care utilization and cost.

Methods

Design:

  • Cluster randomized trial
    • Residents of 16 subsidized housing facilities in Boston, Massachusetts, USA and neighboring communities
    • Randomization at the facility level to intervention or control
  • Baseline assessments were completed before randomization
  • Follow-up assessors were blinded to treatment arm
  • Primary outcomes of interest:
    • Short Physical Performance Battery (SPPB) scores
  • Secondary outcomes:
    • Physical function (TUG, grip strength, self-reported physical activity, functional capacity)
    • Cognition
    • Person-centered measures (balance confidence, health-related quality of life, depression, exercise self-efficacy)
    • Falls, emergency visits, hospitalizations, adverse events
  • Assessments were conducted at six and 12-months

Intervention

  • One year of twice weekly tai chi classes
  • Delivered at set times in a designated community room within the housing facility
  • Provided by eight experienced tai chi instructors under the direction of the principal investigator (PI)
  • Two instructors were assigned to each facility
  • Treatment fidelity assessed by class observation by the PI
  • Home-based practice, for 20-minutes, three times per week using a detailed manual and practice video
  • Monthly social calls from a research assistant

Control group

  • Monthly health promotion group classes, delivered in a common area within each housing facility [to control for the effects of social interactions in the intervention group]
    • 30-minute lecture, 30-minute group discussion
  • Monthly social calls from a research assistant

Inclusion criteria

  • Living in a selected facility
  • Expected to remain in the facility for one year
  • Age 60 years or greater
  • Able to understand instructions in English
  • Able to safely participate in exercise two times per week
  • Able to stand and walk independently
  • Passed cognitive screening (recall test)

Exclusion criteria

  • Already participating in tai chi
  • Unstable or terminal illness
  • Unable to maintain sitting or standing posture
  • Unable to see, hear or understand tai chi instructions and assessment questions

Findings

An “interim analysis for efficacy, futility, and sample size re-estimation was planned after participants enrolled in the first eight of 16 facilities had completed their 12-month assessment.” At the time of the efficacy and futility analysis, the intervention group showed less improvement in SPPB scores at 12 months than the control group, and considerably less improvement than the pre-determined futility criterion. Based on the results of the efficacy and futility analysis, the study was discontinued.

At the time of discontinuation eight sites had completed the 12-month follow up, representing 67 patients and 12 sites had completed six-month follow up, representing 135 patients. The study authors reported the following findings based primarily on the outcomes at six-month follow up as this provided the most complete data source:

  • No statistically significant differences were seen “in any of the clinical, functional, cognitive, or affective outcome measures.”
  • Participants in the intervention group tended to see less improvement in SPPB than the control group.
  • More adverse events and falls were seen in the tai chi group than the control group (not statistically significant)
    • The rate of falls was lower among those who reported more hours of practice of tai chi (both independent and in class).

The study authors noted several possible reasons for the findings:

  • Considerably longer follow up as compared with past studies.
  • Low class attendance rates
    • However, the authors note that several studies reporting benefit from tai chi report similar or lower attendance rates to the current study.
  • Under powered study
    • However, the authors note that if this was the case, there would be positive trends that did not achieve statistical significance. No such positive trends were identified.
  • The “unique sociodemographic characteristics of participants and a failure to differentially target critical environmental, social, and psychological determinants of health.”
    • However, the six-month data did not find an association between frailty or sociodemographic factors and worse response to tai chi.

Limitations

This is one study, representing a total of 135 subjects block-randomized into tai chi or control group. The patient population in question included older adults living within subsidized housing in Boston, Massachusetts.

Relevance to physiotherapy practice in Alberta

Publication bias commonly limits the distribution of negative findings in intervention studies. For this reason alone, the findings of this study are important.

Tai chi is commonly recommended by health professionals as an intervention for older adults. The results of this study suggest that tai chi may not be universally beneficial to individuals commonly encouraged to consider this form of exercise, particularly those with a lower socio-economic status. Physiotherapists incorporating this approach to treatment or encouraging tai chi as a community-based intervention should weigh the complete body of research, and the unique patient context when making patient-specific recommendations.

Disclaimer: The purpose of this summary is to highlight recently published research findings that are not openly accessible. Every effort is made to ensure accuracy and clarity of the summary. Readers are encouraged to review the published article in full for further information.


  1. Lipsitz LA, Macklin EA, Travison TG, Manor B, Gagnon P, Tsai T, Aizpurua II, Lo OY, Wayne PM. A Cluster Randomized Trial of Tai Chi vs Health Education in Subsidized Housing: The MI-WiSH Study. Journal of the American Geriatrics Society, 2019; 67:1812-1819.
  2. Physiotherapy Alberta – College + Association. Introduction to Health Coaching. A Toolkit for Physiotherapists 2019. Available at https://www.physiotherapyalberta.ca/files/health_coaching_toolkit.pdf. Accessed December 18, 2019.