Randomised Controlled Trial Of The Effect Of Tai Chi On Postural Balance Of People With Dementia

Figures & data

Figure 1 Flow diagram of study participation.

Note: See Supplementary Figure S1 for details.

Table 1 Baseline Descriptive Statistics

	Usual Care Group (n=43)	Tai Chi Group (n=42)
People with dementia
Female, n (%)	16 (37%)	18 (43%)
Age mean (SD), range	78.2 (7.5) 61.9–97.4	77.9 (8.3) 59.0–88.0
Type of dementia, n (%)
Alzheimer’s	26 (60%)	30 (71%)
Vascular	5 (12%)	1 (2%)
Alzheimer’s and vascular	6 (14%)	9 (21%)
Other	6 (14%)	2 (5%)
Time since diagnosis (years) median (IQR)	1.4 (2.6) 0.1–7.5	1.1 (2.5) 0.2–7.7
Fallen in past 12 months, n (%)	18 (42%)	19 (45%)
Recruitment site, n (%)
National Health Service 1	11 (26%)	10 (24%)
National Health Service 2	30 (70%)	30 (71%)
National Health Service 3	2 (5%)	2 (5%)
Informal carers
Female, n (%)	35 (81%)	32 (76%)
Age mean (SD) range	70.8 (10.4) 47.5–88.8	72.0 (9.9) 43.4–87.9
Living with PWD, n (%)	38 (88%)	36 (86%)

Table 2 Continuous Outcomes For People With Dementia And Their Informal Carers

	Baseline	6-Month Follow-Up	Mean Difference (95% CI) At Follow-Up
People with dementia
Primary outcome: Timed up and go test mean (SD)^a
Usual care group	18.7 (6.4), n=43	19.7 (5.3), n=34	0.82 (−2.17, 3.81) p = 0.59, d = 0.14
Tai Chi group	18.5 (5.1), n=42	21.1 (8.7), n=36
Secondary outcomes mean (SD)
Berg Balance Scale^b
Usual care group	44.5 (6.8), n=43	44.7 (7.2), n=32	−0.01 (−1.86, 1.83) p = 0.99, d = −0.002
Tai Chi group	45.9 (5.4), n=42	44.8 (5.7), n=36
Postural sway standing on floor (mg/s)^c
Usual care group	166 (43), n=43	164 (22), n=34	1.0 (−14.09, 16.10) p = 0.90, d = 0.03
Tai Chi group	157 (23), n=42	161 (38), n=36
Postural sway standing on foam (mg/s)^c
Usual care group	210 (75), n=43	205 (62), n=34	−6.17 (−29.15,16.82) p = 0.60, d = −0.09
Tai Chi group	209 (63), n=42	198 (46), n=36
Iconographical Falls Efficacy Scale^d
Usual care group	16.1 (6.1), n=43	18.2 (7.2), n=34	−1.53 (−4.43, 1.38) p = 0.30, d = −0.25
Tai Chi group	16.6 (6.0), n=42	17.3 (6.3), n=36
ICEpop CAPability measure for Older people^e
Usual care group	0.88 (0.11), n=43	0.83 (0.14), n=34	0.051 (0.002, 0.100) p = 0.04, d = 0.51
Tai Chi group	0.87 (0.09), n=42	0.86 (0.10), n=36
Mini-Addenbrooke’s Cognitive Examination^f
Usual care group	15.1 (4.3), n=43	13.7 (6.3), n=35	−0.35 (−2.20, 1.49) p = 0.71, d = −0.08
Tai Chi group	16.2 (4.9), n=42	14.5 (6.4), n=36
Informal carers
Secondary outcomes mean (SD)
Timed up and go test^a
Usual care group	13.6 (3.5), n=43	13.9 (2.8), n=36	1.83 (0.12, 3.53) p = 0.04, d = 0.61
Tai Chi group	13.0 (2.4), n=42	15.5 (5.9), n=36
Postural sway standing on floor (mg/s)^c
Usual care group	150 (15), n=43	154 (14), n=36	−4.11 (−10.13, 1.90) p = 0.18, d = −0.32
Tai Chi group	152 (11), n=42	150 (12), n=36
Postural sway standing on foam (mg/s)^c
Usual care group	173 (26), n=43	166 (20), n=36	2.16 (−10.96, 15.28) p = 0.75, d = 0.09
Tai Chi group	170 (20), n=42	168 (32), n=35
ICEpop CAPability measure for Older people^e
Usual care group	0.86 (0.11), n=43	0.79 (0.12), n=34	−0.003 (−0.050, 0.044) p = 0.90, d = −0.03
Tai Chi group	0.83 (0.11), n=41	0.78 (0.13), n=35
Zarit Burden interview (short-form)^g
Usual care group	15.5 (7.4), n=43	17.7 (8.4), n=35	0.52 (−1.93, 2.96) p = 0.68, d = 0.06
Tai Chi group	16.9 (9.8), n=41	18.8 (9.4), n=35

Notes: ^aLower values indicate greater dynamic balance. Mean [SD] seat height at baseline was to standard for the test (46 cms/arm rest height 67 cms, n=43) for usual care (46.6 [3.4]/65.6 [5.0], for n=25 with arm rest) and Tai Chi groups (45.7 [2.7]/65.3 [2.5], for n=18). ^bHigher scores indicate greater functional balance, potential range 0–56. ^cHigher scores indicate worse static balance. ^dHigher scores indicate greater concern, potential range 10–40. ^eHigher scores indicate better capability. ^fHigher scores indicate greater cognitive functioning, potential range 0–30. ^gHigher scores indicate greater burden, potential range 0–48.

Table 3 Falls Outcomes For People With Dementia

	Usual Care Group	Tai Chi Group	Ratio At Follow-Up (95% CI)
Number of falls (number per month of follow-up)^a
6-month follow-up^b	78 (0.312), n=43	44 (0.174), n=42	Falls rate ratio: 0.35 (0.15, 0.81) p = 0.015
Number of injurious falls (number per month of follow-up)^a
6-month follow-up	17 (0.068), n=43	11 (0.043), n=42	Falls rate ratio: 0.62 (0.23, 1.66) p = 0.34
Proportion of participants falling^c
6-month follow-up	17 (47%), n=36	17 (47%), n=36	Odds ratio: 0.97 (0.28, 3.33) p = 0.96
Proportion of participants having an injurious fall^c
6-month follow-up	8 (22%), n=36	9 (25%), n=36	Odds ratio: 1.09 (0.33, 3.56) p = 0.89

Notes: ^aFollow-up (min, max), median months = (0.30, 8.25), 6.41. Calculation of falls rate takes into account length of follow-up and so includes all participants. ^bOne person with dementia in the control group had 17 falls. When this participant was excluded from the analysis, the falls rate ratio changed to 0.46 (95% CI = 0.21, 1.03), p = 0.060. Hypothetically, if this one person had been randomised to the Tai Chi group instead of the control group and they had not participated in the intervention, and they again had 17 falls, then the intention to treat analysis would suggest that the number of falls in each group would have been identical. However, in this hypothetical scenario, the per protocol analysis would exclude this individual and so the incidence of falls would then be as above with a falls rate ratio of 0.46 (95% CI = 0.21, 1.03), p = 0.060. ^cCalculation of proportion of fallers only includes those who were followed up at 6 months.

Data Availability

The electronic, quantitative trial data will be shared with bona fide researchers intending to use the data for non-commercial research purposes, after an embargo period of approximately 24 months (ending January 2021). Access to the following will be restricted to researchers who sign a confidentiality agreement and confirm their intention to use the data is for secondary data analysis for non-commercial research purposes using a Creative Commons licence: statistical analysis plan; where applicable, statistical code (for final analysis of primary outcome measure); and anonymised participant-level dataset and data documentation. Interested parties may make a formal request to access the electronic dataset, which will be approved/declined by the chief investigator in accordance with the Data Management Plan that will detail management of access, sharing, and preservation of the data. Any use of the electronic data set must be requested via Bournemouth University Library ([email protected]) who will collaborate with the chief investigator with regards to access.