Sirinun Boripuntakul

Effects of Tai Chi on Cognition and Fall Risk in Older Adults with Mild Cognitive Impairment: A Randomized Controlled Trial.

To examine whether combined center‐ and home‐based Tai Chi training can improve cognitive ability and reduce physiological fall risk in older adults with amnestic mild cognitive impairment (a‐MCI).

Spatial variability during gait initiation while dual tasking is increased in individuals with mild cognitive impairment

BackgroundGait initiation (GI) is a complex transition phase of gait that can induce postural instability. Gait impairment has been well documented in people with Alzheimer’s disease, but it is still inconclusive in individuals with Mild Cognitive Impairment (MCI). Previous studies have usually investigated gait performance of cognitive impaired persons under steady state walking.ObjectiveThis study aimed to examine spatiotemporal variability during GI under single- and dual-task conditions in people with and without MCI.MethodsSpatiotemporal stepping characteristics and variability under single- and dual-task conditions (counting backwards by 3s) were assessed in 30 older adults with MCI and 30 cognitively intact controls. Mean and coefficients of variation (COV) of swing time, step time, step length and step width were compared between the two groups.ResultsMixed-model repeated measures ANOVA revealed a significant Group x Walking condition interaction for COV of step length and step width (P<0.05). Post-hoc analysis revealed that variability for these measures were significantly larger in the MCI group compared with the control group under the dual-task condition (P<0.05).ConclusionsStep length and step width variability is increased in people with MCI during GI, particularly in a condition involving a secondary cognitive task. These findings suggest that individuals with MCI have reduced balance control when undertaking a challenging walking task such as gait initiation, and this is exacerbated with an added cognitive task. Future studies should prospectively investigate the relationship between GI variability and fall risk in this population.

Specific but not global cognitive functions are associated with gait initiation in older adults

The objective of this study was to examine the association between cognitive ability and gait initiation performance in older adults. Global and specific cognitive functions and spatiotemporal gait parameters during gait initiation were assessed in 60 older adults. Multivariate linear regression was conducted to determine the association between cognitive functions and gait initiation parameters. Results showed that global cognitive function was not associated with any of the spatiotemporal parameters. Poorer performance on measures of executive function and language ability were associated with shorter step length, narrower step width, and longer step time. In addition, poorer performance on test of visuospatial ability was associated with longer step time. In conclusion, specific but not global cognitive functions were associated with gait initiation performance. Clinical gait examination should incorporate gait initiation and cognitive assessments. Rehabilitation strategies aimed at improving cognition and gait initiation performance may be beneficial for preventing falls.

Short-Term Effects of Cognitive Training Program for Individuals with Amnestic Mild Cognitive Impairment: A Pilot Study

ABSTRACT This study examined the effects of a cognitive training program on cognitive function and neurochemistry changes in individuals with amnestic mild cognitive impairment (aMCI). Ten individuals with aMCI were randomly assigned to the experimental (n = 5) and control (n = 5) groups. The experimental group took part in an 18-session cognitive training program over a 6-week period. After completing the cognitive training course, the experimental group demonstrated significant improvement in memory, attention, and executive functions. With respect to the neurochemistry biomarkers, the myoinositol/creatine (mI/Cr) ratio was significantly decreased in the hippocampus, prefrontal cortex, and anterior cingulate cortex of the experimental group after training. Findings demonstrate that the cognitive training program showed promising evidence in improving cognitive functions in individuals with aMCI. The observed cognitive function improvement was accompanied by a decrease of mI levels.

Tai Chi Improves Cognition and Plasma BDNF in Older Adults With Mild Cognitive Impairment: A Randomized Controlled Trial:

Background. Effects of Tai Chi (TC) on specific cognitive function and mechanisms by which TC may improve cognition in older adults with amnestic mild cognitive impairment (a-MCI) remain unknown. Objective. To examine the effects of TC on cognitive functions and plasma biomarkers (brain-derived neurotrophic factor [BDNF], tumor necrosis factor-α [TNF-α], and interleukin-10 [IL-10]) in a-MCI. Methods. A total of 66 older adults with a-MCI (mean age = 67.9 years) were randomized to either a TC (n = 33) or a control group (n = 33). Participants in the TC group learned TC with a certified instructor and then practiced at home for 50 min/session, 3 times/wk for 6 months. The control group received educational material that covered information related to cognition. The primary outcome was cognitive performance, including Logical Memory (LM) delayed recall, Block Design, Digit Span, and Trail Making Test B minus A (TMT B-A). The secondary outcomes were plasma biomarkers, including BDNF, TNF-α, and IL-10. Results. At the end of the trial, performance on the LM and TMT B-A was significantly better in the TC group compared with the control group after adjusting for age, gender, and education (P < .05). Plasma BDNF level was significantly increased for the TC group, whereas the other outcome measures were similar between the 2 groups after adjusting for age and gender (P < .05). Conclusions. TC training significantly improved memory and the mental switching component of executive function in older adults with a-MCI, possibly via an upregulation of BDNF.

The validity and reliability of the Swaymeter for postural sway measurement in typically developing children aged between 7–12 years

BACKGROUND The Swaymeter is a simple devicefor measuring postural sway. It consists of a 40-cm-long rod with a vertically mounted pen at the end of the rod that measures the displacement of the body at waist level. RESEARCH QUESTION This device could be an effective tool for measuring postural sway in children. However, the validity and reliability of the Swaymeter in children has not been evaluated. In this study, we aimed to evaluate the validity and reliability of the Swaymeter in typically developing children aged 7-12 years. METHOD The Swaymeter procedure was randomly measured in quiet bipedal stance under 4 conditions: eyes open and eyes closed on the floor, eyes open and eyes closed on foam, 30 s were performed in each condition. There were 15 children participated in the validity study. The postural sway was measured concurrently with the motion capture system with two reflective markers on the top of the pen and 12th thoracic vertebra level in three trials with four testing conditions. Additionally, 36 children participated in test-retest reliability. Three measurements were performed on the same day and one week later. RESULTS Swaymeter had a moderate to good correlation with motion capture system (r = 0.637-0.979). The test-retest reliability of the Swaymeter showed moderate to good reliability for immediate test-retest (ICC = 0.51-0.87). However, inter-session reliability revealed moderate to good reliability except for the AP variable that showed low reliability. Good to excellent reliability was found in sway area variable (ICCs between 0.74 and 0.92) for all measurements. SIGNIFICANCE Postural sway measure by Swaymeter was valid and reliable in typically developing children aged 7-12 years and suitable for applying to assess postural sway in typically developing children.

The role of cognitive function and physical activity in physical decline in older adults across the cognitive spectrum

ABSTRACT Objectives: The aim of this study was to investigate physical decline over 1-year in a cohort of older people across the cognitive spectrum. Methods: Physical function was assessed using the Physiological Profile Assessment (PPA) in 593 participants (cognitively normal [CN]: n = 342, mild cognitive impairment [MCI]: n = 77, dementia: n = 174) at baseline and in 490 participants available for reassessment 1-year later. Neuropsychological performance and physical activity (PA) were assessed at baseline. Results: Median baseline PPA scores for CN, MCI and dementia groups were 0.41 (IQR = −0.09–1.02), 0.66 (IQR = −0.06–1.15) and 2.37 (IQR = 0.93–3.78) respectively. All baseline neuropsychological domains and PA were significantly associated with baseline PPA. There were significant interaction terms (Time × Cognitive Group, Global Cognition, Processing Speed, Executive Function and PA) in the models investigating PPA decline. In multivariate analysis the Time × Executive Function and PA interaction terms were significant, indicating that participants with poorer baseline executive function and reduced PA demonstrated greater physical decline when compared to individuals with better executive function and PA respectively. Discussion: Having MCI or dementia is associated with greater physical decline compared to CN older people. Physical inactivity and executive dysfunction were associated with physical decline in this sample, which included participants with MCI and dementia. Both factors influencing physical decline are potentially amenable to interventions e.g. exercise.