Effects of education on very mild dementia among Chinese people in Hong Kong: potential mediators in the Cantonese Mini-Mental State Examination tasks

Prospective associations between change in sleep duration and cognitive impairment: Findings from the Singapore Chinese Health Study

BACKGROUND

The relation of changes in sleep duration with risk of cognitive impairment are inconclusive. This study evaluated the prospective relationships of changes in sleep duration with risk of cognitive impairment in Singapore Chinese.

METHODS

We used data from 16,948 Chinese men and women who were aged 45-74 years at baseline (1993-1998) during recruitment into the Singapore Chinese Health Study cohort. Daily sleep duration was assessed at baseline, follow-up 2 (2006 to 2010) and follow-up 3 interviews (2014-2016). Cognitive function was evaluated with a Singapore-Modified Mini-Mental State Examination at follow-up 3 interviews when participants were 61-96 years old. Multivariable logistic regression models were used to calculate odd ratios (ORs) and 95% confidence intervals (95% CIs) for cognitive impairment.

RESULTS

Of the 16,948 participants, 14.4% were defined to have cognitive impairment. Compared with 7 h/day sleep at both baseline and follow-up 2, the OR (95% CI) for cognitive impairment was 1.50 (1.04-2.16) for those who maintained long sleep duration (≥9 h/day), 2.18 (1.37-3.45) for those who prolonged sleep from short duration (≤5 h/day) to long duration (≥9 h/day), and 1.55 (1.20-2.02) for those who prolonged sleep from recommended duration (7 h/day) to long duration. The highest risk was observed in those who shortened sleep from long to short duration (2.93, 1.35-6.34).

LIMITATIONS

Measures of sleep were self-reported.

CONCLUSIONS

Substantial changes in sleep duration over time were associated with higher risks of cognitive impairment. The findings underscore the importance of maintaining optimal sleep duration for the prevention of cognitive impairment.

Adiposity, Weight Change, and Risk of Cognitive Impairment: The Singapore Chinese Health Study

BACKGROUND

Few prospective studies with long duration of follow-up have assessed the relations of body mass index (BMI) and weight change with cognitive function, especially in Asian populations.

OBJECTIVE

To investigate whether BMI and weight change in midlife are associated with cognitive impairment in old age.

METHODS

We used data from 14,691 participants in the Singapore Chinese Health Study and computed weight change as the difference between weight reported at baseline (1993-1998) at mean age of 53.0 years and follow-up 1 (1999-2004) at mean age of 58.6 years. Cognitive impairment was determined using education-specific cut-offs of the Singapore Modified Mini-Mental State Examination at follow-up 3 (2014-2016) at mean age of 72.9 years. We used multivariable logistic regression models to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the associations.

RESULTS

Obesity (as defined BMI ≥27.5 kg/m2) was associated with a higher risk of cognitive impairment at baseline (OR 1.33, 95% CI 1.12-1.58) and follow-up 1 (OR 1.30, 95% CI 1.10-1.54) compared to BMI of 18.5-22.9 kg/m2. Underweight (BMI <18.5 kg/m2) was not associated with a significant risk either at baseline (OR 0.91, 95% CI 0.73-1.13) or follow-up 1 (OR 1.05, 95% CI 0.85-1.28). Compared to participants with <5% weight change, the ORs (95% CIs) of cognitive impairment were 1.20 (1.03-1.41) for those with 5-9.9% weight loss, 1.53 (1.29-1.81) for ≥10% weight loss, 1.00 (0.85-1.17) for 5-9.9% weight gain, and 1.50 (1.28-1.75) for ≥10% weight gain.

CONCLUSION

Obesity, weight loss, and excessive weight gain at midlife were associated with an increased risk of cognitive impairment at old age.

Dairy, soy, and calcium consumption and risk of cognitive impairment: the Singapore Chinese Health Study

PURPOSE

It is unclear if midlife consumption of dairy and soy food intake, and their components of calcium and isoflavones (in soy), is related to cognitive impairment in elderly.

METHODS

We used baseline data on lifestyle and habitual diet of 16,948 participants collected during their recruitment into the Singapore Chinese Health Study from 1993 to 1998, and data on their cognitive function, measured using a 30-item Singapore modified Mini-Mental State Examination, during follow-up interviews from 2014 to 2016. We used multivariable logistic regression models to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for developing cognitive impairment.

RESULTS

Higher dairy intake was associated with a lower risk of cognitive impairment in a dose-dependent manner (P for trend = 0.009). Compared to the lowest quartile of dairy intake, ORs (95% CIs) were 0.93 (0.81-1.07) for the second, 0.88 (0.76-1.01) for the third, and 0.82 (0.72-0.94) for the fourth quartiles of intake. Similar results were found for dairy calcium intake (P for trend = 0.008). However, there was no statistically significant association for intake of soy (OR comparing extreme quartiles 0.99, 95% CI 0.87-1.14, P for trend = 0.92), isoflavones (OR 1.01, 95% CI 0.88-1.15, P for trend = 0.90) or non-dairy calcium (OR 1.06, 95% CI 0.86-1.30, P for trend = 0.81) with risk of cognitive impairment.

CONCLUSIONS

Dairy intake at midlife could have a protective association against cognitive impairment that may not be attributed to its calcium content alone, while soy or isoflavone intake was not associated with the cognition of elderly in our study.

Validation of Montreal Cognitive Assessment-Basic in a sample of elderly Egyptians with neurocognitive disorders

BACKGROUND AND OBJECTIVES

Montreal Cognitive Assessment-Basic (MoCA-B) is a modified version of the MoCA that is especially suitable for use in elderly subjects with low education. The Authors translated the tool into Arabic and they aimed at validation of this tool in a sample of elderly Egyptians.

METHODS

The study included 93 patients, 60 years and older, fulfilling the DSM-5 criteria of Mild Neurocognitive Disorder (NCD) (39 patients) and Major Neurocognitive Disorder (54 patients) that were compared to 112 community dwelling elder subjects. All subjects were assessed using the MoCA-B, Mini-Mental State Examination (MMSE), and the Clinical Dementia Rating Scale (CDR) in addition to the required laboratory and radiological investigations.

RESULTS

MoCA-B demonstrated good internal consistency (Cronbach's alpha = 0.915) and content validity in discrimination between normal and diseased subjects. It showed superior sensitivity and specificity when compared to MMSE in screening for Mild NCD (AUC MoCA-B = 0.988 versus MMSE = 0.939). The recommended cut-off was 21/22 with sensitivity of 92.5% and specificity of 98.2% for detecting Mild NCD and 16/17 with sensitivity of 90.7% and specificity of 97.4% for detecting Major NCD (dementia).

CONCLUSION

The Arabic MoCA-B is a valid cognitive assessment tool in elderly Egyptian subjects.

Multicomponent intervention combining a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling older adults with probable dementia: A multi-center, randomized controlled trial

OBJECTIVE

This research study aims to evaluate the effectiveness of a multicomponent intervention that combines a cognitive stimulation group and tai chi to reduce cognitive decline among community-dwelling Chinese older adults with probable dementia.

METHODS

A multi-center, randomized controlled trial design was adopted in this study. In addition to treat as usual, the treatment group (n = 41) participated in a structured cognitive stimulation group followed by tai chi twice a week, with a total of 14 sessions held during the study period. The control group (n = 39) received treat as usual. Mattis Dementia Rating Scale and Mini-Mental State Examination were used for assessing the cognitive abilities of participants in the pre- and post-treatment periods.

RESULTS

A 2 × 2 repeated measures analysis of covariance demonstrated that the treatment group was more effective than the control group on improving Dementia Rating Scale score (F = 7.45, p < .01) with a moderate effect size (partial eta square = .09) and Mini-Mental State Examination score (F = 9.96, p < .01) with a moderate to large effect size (partial eta square = .12) after controlling for age, gender, educational level, marital status, and number of physical illnesses.

CONCLUSION

The present study demonstrates the effectiveness of the multicomponent intervention on improving cognitive ability among community-dwelling older adults with probable dementia, suggesting that the multicomponent intervention can facilitate early identification, assessment, and treatment for community-dwelling older adults with probable dementia.

The utility of a non-verbal prospective memory measure as a sensitive marker for early-stage Alzheimer's disease in Hong Kong

ABSTRACT Background: With the proportion of older adults in Hong Kong projected to double in size in the next 30 years, it is important to develop measures for detecting individuals in the earliest stage of Alzheimer's disease (AD, 0.5 in Clinical Dementia Rating, CDR). We tested the utility of a non-verbal prospective memory task (PM, ability to remember what one has to do when a specific event occurs in the future) as an early marker for AD in Hong Kong Chinese. Methods: A large community dwelling sample of older adults who are healthy controls (CDR 0, N = 125), in the earliest stage of AD (CDR 0.5, N = 125), or with mild AD (CDR 1, N = 30) participated in this study. Their reaction time/accuracy data were analyzed by mixed-factor analyses of variance to compare the performance of the three CDR groups. Logistic regression analyses were performed to test the discriminative power of these measures for CDR 0 versus 0.5 participants. Results: Prospective memory performance declined as a function of AD severity: CDR 0 > CDR 0.5 > CDR 1, suggesting the effects of early-stage AD and AD progression on PM. After partialling out the variance explained by psychometric measures (e.g., ADAS-Cog), reaction time/accuracy measures that reflected the PM still significantly discriminated between CDR 0 versus 0.5 participants in most of the cases. Conclusion: The effectiveness of PM measures in discriminating individuals in the earliest stage of AD from healthy older adults suggests that these measures should be further developed as tools for early-stage AD discrimination.