Ada W. T. Fung

A 1-year randomized controlled trial comparing mind body exercise (Tai Chi) with stretching and toning exercise on cognitive function in older Chinese adults at risk of cognitive decline.

OBJECTIVES To compare the effectiveness of Chinese-style mind-body exercise (24 forms simplified Tai Chi) versus stretching and toning exercise in the maintenance of cognitive abilities in Chinese elders at risk of cognitive decline. DESIGN A 1-year single-blind cluster randomized controlled trial. SETTINGS Community centers and residential homes for elders in Hong Kong. PARTICIPANTS A total of 389 subjects at risk of cognitive decline (Clinical Dementia Rating, CDR 0.5 or amnestic-MCI) participated in an exercise intervention program. INTERVENTION A total of 171 subjects were trained with Tai Chi (Intervention [I]) and 218 were trained with stretching and toning exercise (Control [C]). METHODS Cognitive and functional performance were assessed at the baseline, and at 5, 9, and 12 months. Data were analyzed using multilevel mixed models. Primary outcomes included progression to clinical dementia as diagnosed by DSM-IV criteria, and change of cognitive and functional scores. Secondary outcomes included postural balance measured by the Berg Balance Scale neuropsychiatric and mood symptoms measured by the Neuropsychiatric Inventory, and Cornell Scale for Depression in Dementia. RESULTS At 1 year, 92 (54%) and 169 (78%) participants of the I and C groups completed the intervention. Multilevel logistic regression with completers-only analyses controlled for baseline differences in education revealed that the I group had a trend for lower risk of developing dementia at 1 year (odds ratio 0.21, 95% CI 0.05-0.92, P = .04). The I group had better preservation of CDR sum of boxes scores than the C group in both intention-to-treat (P = .04) and completers-only analyses (P = .004). In completers-only analyses, the I group had greater improvement in delay recall (P = .05) and Cornell Scale for Depression in Dementia scores (P = .02). CONCLUSION Regular exercise, especially mind-body exercise with integrated cognitive and motor coordination, may help with preservation of global ability in elders at risk of cognitive decline; however, logistics to promote long-term practice and optimize adherence needs to be revisited.

Interim follow-up of a randomized controlled trial comparing Chinese style mind body (Tai Chi) and stretching exercises on cognitive function in subjects at risk of progressive cognitive decline

We reported the interim findings of a randomized controlled trial (RCT) to examine the effects of a mind body physical exercise (Tai Chi) on cognitive function in Chinese subjects at risk of cognitive decline.

Self-efficacy Is Associated With Less Burden and More Gains From Behavioral Problems of Alzheimer’s Disease in Hong Kong Chinese Caregivers

PURPOSE To test the effects of different self-efficacy beliefs on caregiver appraisals and depressive symptoms. We hypothesized that self-efficacy has a direct effect on depression while moderating the effects of behavioral problems on both negative (i.e., burden) and positive (i.e., uplifting) appraisals. DESIGN AND METHODS Ninety-nine Chinese caregivers of relatives with Alzheimers disease responded to measures of self-efficacy, positive gains, burden, depression, and care recipient behavioral problems. Data were analyzed using confirmatory factor analysis and multiple regression. RESULTS Confirmatory factor analysis supported a 3-factor structure for the Revised Scale for Caregiving Self-Efficacy (obtaining respite, responding to disruptive behaviors, and controlling upsetting thoughts). Interaction effects in regression showed that caregivers with higher self-efficacy in controlling upsetting thoughts had more positive gains and less burden when confronted with more behavioral problems. Self-efficacy in obtaining respite had direct effects on burden and depression, and self-efficacy in responding to disruptive behaviors had a direct effect on positive gains, but not moderating effects. IMPLICATIONS The results supported the multidimensional structure of caregiver self-efficacy and showed that efficacy in controlling upsetting thoughts was most important in buffering the effects of behavioral problems on burden and positive gains among Chinese caregivers. Interventions for dementia caregivers may be more effective if more emphasis is given on changing negative thoughts.

Neuropsychiatric symptoms are associated with increased risks of progression to dementia: a 2-year prospective study of 321 Chinese older persons with mild cognitive impairment

BACKGROUND studies have suggested that neuropsychiatric (NP) symptoms influence the development of dementia among older adults. But, the results are inconsistent and there is limited information about NP symptoms in population-based samples. OBJECTIVE to explore the association between NP symptoms and risk of cognitive decline in Chinese older persons residing in the community. DESIGN prospective study. SETTING community sample. SUBJECTS a total of 321 community-dwelling Chinese older persons aged 60 or over with mild cognitive impairment participated in the study. METHODS at baseline, each subject was assessed with Clinical Dementia Rating (CDR), Mini-Mental State Examination, list learning and delayed recall, and Category Verbal Fluency Test. Severity of NP symptoms was evaluated with Neuropsychiatric Inventory (NPI). Global cognitive status at the end of 2-year study period was determined by CDR. RESULTS at baseline, 40.5% of participants exhibited one or more NP symptoms (NPI total score ≥ 1). Night-time behaviours (22.1%), depression (16.8%), apathy (14.0%) and anxiety (12.8%) were the most common NP symptoms. At the end of 2-year follow-up, 27.5% of participants with depression at baseline developed dementia, compared with 14.8% of those without depression (χ² = 4.90, P= 0.03). Aberrant motor behaviour was also significantly associated with deterioration in cognition (χ² = 5.84, P= 0.02), although it was an infrequent occurrence. On logistic regression analysis, only depression at baseline was shown to be a risk factor for progression to dementia (OR= 2.40, 95% CI 1.05-5.46, P= 0.04). CONCLUSION depression in non-demented older persons may represent an independent dimension reflecting early neuronal degeneration. Further studies should be conducted to assess whether effective management of NP symptoms exerts beneficial effects on cognitive function.

The Prevalence of Mild Cognitive Impairment in Diverse Geographical and Ethnocultural Regions: The COSMIC Collaboration

Background Changes in criteria and differences in populations studied and methodology have produced a wide range of prevalence estimates for mild cognitive impairment (MCI). Methods Uniform criteria were applied to harmonized data from 11 studies from USA, Europe, Asia and Australia, and MCI prevalence estimates determined using three separate definitions of cognitive impairment. Results The published range of MCI prevalence estimates was 5.0%–36.7%. This was reduced with all cognitive impairment definitions: performance in the bottom 6.681% (3.2%–10.8%); Clinical Dementia Rating of 0.5 (1.8%–14.9%); Mini-Mental State Examination score of 24–27 (2.1%–20.7%). Prevalences using the first definition were 5.9% overall, and increased with age (P < .001) but were unaffected by sex or the main races/ethnicities investigated (Whites and Chinese). Not completing high school increased the likelihood of MCI (P ≤ .01). Conclusion Applying uniform criteria to harmonized data greatly reduced the variation in MCI prevalence internationally.

Examining the association between late-life leisure activity participation and global cognitive decline in community-dwelling elderly Chinese in Hong Kong.

This study examines the association between late‐life leisure activity participation and global cognitive decline in community‐dwelling elderly Chinese in Hong Kong.

The Social Networks of Hong Kong Chinese Family Caregivers of Alzheimer’s Disease: Correlates With Positive Gains and Burden

PURPOSE To examine the social networks of family caregivers of persons with Alzheimers disease and the degree to which network characteristics were associated with satisfaction with social support, burden, and positive gains. DESIGN AND METHODS A total of 142 Chinese caregivers responded to measures of structural support, positive exchanges, and negative exchanges using the social convoy questionnaire, as well as to measures of social support satisfaction, burden, role overload, positive gains, self-rated health, and behavioral and psychological symptoms of dementia (BPSD) of the care recipient. Data were analyzed using multiple regression. RESULTS The caregivers had small networks (mean = 4.4 persons). They reported few negative exchanges with network members and higher emotional than instrumental support, while being rather satisfied with the social support obtained. Surprisingly, both spouse/sibling and adult child caregivers excluded many close kin, in particular ~40% of their children, from their networks. A larger network was associated with higher social support satisfaction and positive gains, and lower role overload. Controlling for network size and social support satisfaction, positive exchanges were associated with higher positive gains, whereas negative exchanges were associated with higher burden and overload. Caregivers who experienced more BPSD and poorer self-rated health also reported lower support satisfaction and positive gains, as well as higher burden and overload. IMPLICATIONS Under the influence of collectivism, individuals may shoulder the responsibilities of caregiving for the collective well-being of the family and end up being isolated and disappointed when expectations of family support were not forthcoming, to the extent that even ties with close kin may be severed.

Examining the association between participation in late-life leisure activities and cognitive function in community-dwelling elderly Chinese in Hong Kong

BACKGROUND Growing evidence suggests that participation in late-life leisure activity may have beneficial effects on cognitive function. The objective of the study was to evaluate the association between leisure activity participation and cognitive function in an elderly population of community-dwelling Hong Kong Chinese. METHODS 512 participants were assessed in the follow-up study of a population-based community survey of the prevalence of cognitive impairment among Hong Kong Chinese aged 60 years and over. Leisure activities were classified into four categories (physical, intellectual, social and recreational). Information regarding leisure activity participation, cognitive function and other variables was collected. Multivariate linear regression analyses were performed to examine the association between leisure activity participation and cognitive function. RESULTS A higher level of late-life leisure activity participation, particularly in intellectual activities, was significantly associated with better cognitive function in the elderly, as reflected by the results of the Cantonese Mini-mental State Examination (p = 0.007, 0.029 and 0.005), the Category Verbal Fluency Test (p = 0.027, 0.003 and 0.005) and digit backward span (p = 0.031, 0.002 and 0.009), as measured by the total frequency, total hours per week and total number of subtypes, respectively; the Chinese Alzheimers Disease Assessment Scale-Cognitive Subscale (p = 0.045) and word list learning (p = 0.003), as measured by the total number of subtypes; and digit forward span (p = 0.007 and 0.015), as measured by the total hours per week and total number of subtypes, respectively. CONCLUSION Late-life intellectual activity participation was associated with better cognitive function among community-dwelling Hong Kong elderly Chinese.

Would Older Adults with Mild Cognitive Impairment Adhere to and Benefit from a Structured Lifestyle Activity Intervention to Enhance Cognition?: A Cluster Randomized Controlled Trial

Background Epidemiologic evidence suggests that cognitive and physical activities are associated with better cognition in late life. The present study was conducted to examine the possible benefits of four structured lifestyle activity interventions and compare their effectiveness in optimizing cognition for older adults with mild cognitive impairment (MCI). Method and Findings This was a 12-month cluster randomized controlled trial. 555 community-dwelling Chinese older adults with MCI (295 with multiple-domain deficits (mdMCI), 260 with single-domain deficit (sdMCI)) were recruited. Participants were randomized into physical exercise (P), cognitive activity (C), integrated cognitive and physical exercise (CP), and social activity (S, active control) groups. Interventions comprised of one-hour structured activities three times per week. Primary outcome was Clinical Dementia Rating sum of boxes (CDR-SOB) scores. Secondary outcomes included Chinese versions of Alzheimer’s Disease Assessment Scale - Cognitive subscale (ADAS-Cog), delayed recall, Mini-Mental State Examination, Category Verbal Fluency Test (CVFT) and Disability Assessment for Dementia – Instrumental Activities of Daily Living (DAD-IADL). Percentage adherence to programs and factors affecting adherence were also examined. At 12th month, 423 (76.2%) completed final assessment. There was no change in CDR-SOB and DAD-IADL scores across time and intervention groups. Multilevel normal model and linear link function showed improvement in ADAS-Cog, delayed recall and CVFT with time (p<0.05). Post-hoc subgroup analyses showed that the CP group, compared with other intervention groups, had more significant improvements of ADAS-Cog, delayed recall and CVFT performance with sdMCI participants (p<0.05). Overall adherence rate was 73.3%. Improvements in ADAS-Cog and delayed recall scores were associated with adherence after controlling for age, education, and intervention groups (univariate analyses). Conclusions Structured lifestyle activity interventions were not associated with changes in everyday functioning, albeit with some improvements in cognitive scores across time. Higher adherence was associated with greater improvement in cognitive scores. Factors to enhance adherence should be specially considered in the design of psychosocial interventions for older adults with cognitive decline. Trial Registration ClinicalTrials.gov ChiCTR-TRC-11001359

Disturbance of attention network functions in Chinese healthy older adults: an intra-individual perspective.

BACKGROUND Intra-individual variability (IIV) and the change of attentional functions have been reported to be susceptible to both healthy ageing and pathological ageing. The current study aimed to evaluate the IIV of attention and the age-related effect on alerting, orienting, and executive control in cognitively healthy older adults. METHOD We evaluated 145 Chinese older adults (age range of 65-80 years, mean age of 72.41 years) with a comprehensive neuropsychological battery and the Attention network test (ANT). A two-step strategy of analytical methods was used: Firstly, the IIV of older adults was evaluated by the intraindividual coefficient of variation of reaction time (ICV-RT). The correlation between ICV-RT and age was used to evaluate the necessity of subgrouping. Further, the comparisons of ANT performance among three age groups were performed with processing speed adjusted. RESULTS Persons correlation revealed significant positive correlations between age and IIV (r = 0.185, p = 0.032), age and executive control (r = 0.253, p = 0.003). Furthermore, one-way ANOVA comparisons among three age groups revealed a significant age-related disturbance on executive control (F = 4.55, p = 0.01), in which oldest group (group with age >75 years) showed less efficient executive control than young-old (group with age 65-70 years) (Conventional score, p = 0.012; Ratio score, p = 0.020). CONCLUSION Advancing age has an effect on both IIV and executive attention in cognitively healthy older adults, suggesting that the disturbance of executive attention is a sensitive indicator to reflect healthy ageing. Its significance to predict further deterioration should be carefully evaluated with prospective studies.