The Optimal Frequency of Tai Chi Exercises for Knee Osteoarthritis
February 23, 2018 - Therapeutic exercise, such as Tai Chi, is a currently recommended non-pharmacological treatment for knee osteoarthritis (KOA). But the optimal treatment dose (frequency or duration) has not been determined.
In a research paper published in January of 2018 by American Academy of Physical Medicine and Rehabilitation, Tufts Medical Center examined dose-response relationships, minimal effective dose, and baseline factors associated with the timing of response from two exercise interventions in KOA: a 12-week Tai Chi program and Physical Therapy.
Their research was conducted in an urban tertiary care academic hospital, with 182 participants. The mean age of the participants was 61 years; 70% of them were female and 55% were white.
The researchers defined dose as cumulative attendance-weeks of intervention, and treatment response as >=20% and >=50% improvement in pain and function. Using log-rank tests, they compared time-to-response between interventions; and used Cox regression to examine baseline factors associated with timing of response, including physical and psychosocial health, physical performance, outcome expectations, self-efficacy, and biomechanical factors.
Both Tai Chi and Physical Therapy had an approximately linear dose-response effect resulting in a 9 to 11-point reduction in pain and a 32 to 41-point improvement in function per attendance-week. There was no significant difference in overall time-to-response for pain and function between treatment groups. Median time-to-response for >=20% improvement in pain and function was 2 attendance-weeks and 4 to 5 attendance-weeks for >=50% improvement. On multivariable models, outcome expectations were independently associated with incident function response.
The researchers concluded that for Tai Chi and Physical Therapy, the minimum effective doses range from 2-5 weeks, and patient perceived benefits of exercise influence the timing of response in KOA. These results may help clinicians optimize patient-centered exercise treatments and better manage patient expectations.