Effectiveness of tai chi as a community-based falls prevention intervention: a randomized controlled trial.

OBJECTIVES: To compare the effectiveness of tai chi and low-level exercise in reducing falls in older adults; to determine whether mobility, balance, and lower limb strength improved and whether higher doses of tai chi resulted in greater effect.

DESIGN: Randomized controlled trial.

SETTING: Eleven sites throughout New Zealand.

PARTICIPANTS: Six hundred eighty-four community-residing older adults (mean age 74.5; 73% female) with at least one falls risk factor.

INTERVENTION: Tai chi once a week (TC1) (n = 233); tai chi twice a week (TC2) (n = 220), or a low-level exercise program control group (LLE) (n = 231) for 20 wks.

MEASUREMENTS: Number of falls was ascertained according to monthly falls calendars. Mobility (Timed-Up-and-Go Test), balance (step test), and lower limb strength (chair stand test) were assessed.

RESULTS: The adjusted incident rate ratio (IRR) for falls was not significantly different between the TC1 and LLE groups (IRR = 1.05, 95% confidence interval (CI) = 0.83-1.33, P = .70) or between the TC2 and LLE groups (IRR = 0.88, 95% CI = 0.68-1.16, P = .37). Adjusted multilevel mixed-effects Poisson regression showed a significant reduction in logarithmic mean fall rate of -0.050 (95% CI = -0.064 to -0.037, P < .001) per month for all groups. Multilevel fixed-effects analyses indicated improvements in balance (P < .001 right and left leg) and lower limb strength (P < .001) but not mobility (P = .54) in all groups over time, with no differences between the groups (P = .37 (right leg), P = .66 (left leg), P = .21, and P = .44, respectively).

CONCLUSION: There was no difference in falls rates between the groups, with falls reducing similarly (mean falls rate reduction of 58%) over the 17-month follow-up period. Strength and balance improved similarly in all groups over time.