The relationship between cognition and depressive symptoms, and factors modifying this association, in Alzheimer's disease: A multivariate multilevel model

The longitudinal relationship between meaning in life, depressive symptoms, life satisfaction, and cognitive functioning for older adults with Alzheimer's disease

Studies show the importance of the personal experience of meaning in life for older adults, but adults with dementia have been largely excluded from this research. The current study examined the longitudinal predictive effect of meaning in life for the psychological and cognitive functioning of older adults with Alzheimer's disease and whether cognitive decline predicted presence of meaning in life. On three yearly measurement occasions, presence of meaning in life, depressive symptoms, life satisfaction, and cognitive functioning were assessed in structured interviews with a convenience sample of 140 older adults with Alzheimer's disease from nine nursing homes in Belgium. Cross-lagged panel and latent growth curve models were used to analyze the longitudinal relationships between the variables. Over the three measurement waves, participants with higher presence of meaning reported lower depressive symptoms one year later. Presence of meaning and life satisfaction predicted each other over time, but only between the first and second wave. The analyses showed no strong evidence for a longitudinal association between meaning in life and cognitive functioning in either direction. The findings emphasize the importance of the experience of meaning in life for the psychological functioning of older adults with Alzheimer's disease. The lack of evidence for associations between meaning and cognitive functioning questions the prevailing view that intact cognitive abilities are a necessity for experiencing meaning. More attention to the potential of meaning interventions for persons with dementia is warranted.

Prospective Associations of Tea Consumption With Risk of Cognitive Decline in the Elderly: A 1-Year Follow-Up Study in China

Background

Previous studies show that the consumption of tea is associated with several beneficial outcomes for brain health, but there is little data among the elderly in China.

Objective

The objective was to explore the longitudinal relationship between tea consumption and the risk of cognitive decline.

Methods

The current data was obtained from the China Longitudinal Aging Study (CLAS), and a total of 3,246 residents aged 60 years and above were recruited in this study. Some of them (N = 111) underwent a standard T1-weighted magnetic resonance imaging (MRI), from which the volumes of the corpus callosum (CC) and hippocampus were calculated, and detailed tea consumption information was obtained through a standardized questionnaire at baseline. The cognitive diagnosis of each participant was made by attending psychiatrists at baseline and follow-up. Their overall cognitive function was assessed by the Montreal Cognitive Assessment (MoCA), while their associative learning ability was assessed by an associative learning test (ALT). Finally, 1,545 elderly with normal cognitive function completed the baseline and follow-up assessment and were included in the final study.

Results

After controlling gender, education, smoking, take exercise and hobbies, we found that the elderly with tea consumption habits had a lower incidence rate of cognitive decline (p = 0.002, OR = 0.604, 95%CI:0.437~0.836) and tea consumption was negatively correlated with the change scores of MoCA (r = -0.056, p = 0.029). What's more, the CC_posterior volume of tea drinkers was significantly smaller than that of non-tea drinkers, while the baseline ALT score of tea drinkers was significantly higher than that of non-tea drinkers. The results of correlation analysis showed that the CC_posterior volume was significantly correlated with ALT change score (r = -0.319, p = 0.010).

Conclusions

The habit of tea consumption is associated with less incidence of cognitive impairment among the Chinese elderly, and it may prevent a decline in memory and associative learning by affecting the volume of the posterior corpus callosum.

Biological, Psychological, and Social Determinants of Depression: A Review of Recent Literature

Depression is one of the leading causes of disability, and, if left unmanaged, it can increase the risk for suicide. The evidence base on the determinants of depression is fragmented, which makes the interpretation of the results across studies difficult. The objective of this study is to conduct a thorough synthesis of the literature assessing the biological, psychological, and social determinants of depression in order to piece together the puzzle of the key factors that are related to this condition. Titles and abstracts published between 2017 and 2020 were identified in PubMed, as well as Medline, Scopus, and PsycInfo. Key words relating to biological, social, and psychological determinants as well as depression were applied to the databases, and the screening and data charting of the documents took place. We included 470 documents in this literature review. The findings showed that there are a plethora of risk and protective factors (relating to biological, psychological, and social determinants) that are related to depression; these determinants are interlinked and influence depression outcomes through a web of causation. In this paper, we describe and present the vast, fragmented, and complex literature related to this topic. This review may be used to guide practice, public health efforts, policy, and research related to mental health and, specifically, depression.

Long Sleep Duration Associated With Cognitive Impairment in Chinese Community-Dwelling Older Adults

ABSTRACT

We aimed to examine the association between sleep duration and impaired cognitive function in different cognitive domains in Chinese community-dwelling older adults. A total of 1591 participants (≥60 years) were divided into five groups: ≤6 hours (very short sleep duration), >6 to 7 hours (short sleep duration), ≥7 to 8 hours (moderate sleep duration), >8 to 9 hours (moderately long sleep duration), and >9 hours (long sleep duration), according to sleep duration. Cognitive function was assessed using the Mini-Mental State Examination. Long sleep duration significantly increased the likelihood of cognitive impairment. In addition to attention, long sleep duration was negatively related to poorer global cognition and other cognitive domain functions. With the stratification of age groups, long sleep duration was negatively associated with other cognitive domain functions except delayed recall in older elderly (≥75 years) people, but not in younger elderly (60-74 years) people. Long sleep duration was associated with higher rates of cognitive impairment, poorer global cognition, and declined orientation, memory, language ability, and executive function in Chinese community-dwelling older adults, which was more significant in older elderly people.

Mediating effects of lower extremity function on the relationship between night sleep duration and cardiovascular disease risk: a cross-sectional study in elderly Chinese without cardiovascular diseases

OBJECTIVE

The purpose of this study is to investigate the mediating effect of physical performance on the relationship between night sleep duration and risk of cardiovascular disease (CVD) in elderly Chinese without CVD.

METHODS

782 participants without CVD over 65 years (average: 70.82±3.86 years, 448 women) were included in this study. CVD risk was calculated by the Framingham Risk Score and participants were divided into four groups of night sleep duration (in hours): <7 hours, ≥7-8 hours, >8-9 hours and >9 hours. Upper extremity function was measured by grip strength and lower extremity function was measured by the Short Physical Performance Battery (SPPB), consisting of balance, 4 m walk and chair stands tests.

RESULTS

After adjusting for covariates, long night sleep duration (>9 hours) and CVD risk were significantly positively associated compared with moderate night sleep duration (≥7-8 hours) (β=1.152; 95% CI 0.05 to 2.25). SPPB total score (indirect effect ab=-0.122; 95% CI -0.291 to -0.0008) rather than grip strength partially mediated the relationship between long night sleep duration and CVD risk, in which chair stands played a major mediating role (indirect effect ab=-0.171; 95% CI -0.040 to -0.0006), while balance (indirect effect ab=-0.016; 95% CI -0.100 to 0.063) and 4 m walk (indirect effect ab=0.048; 95% CI -0.066 to 0.201) did not.

CONCLUSIONS

Lower extremity function, especially lower limb muscle strength, partially mediates a positive association between long night sleep duration and CVD risk in the elderly without CVD. Suitable interventions for physical performance and sleep may minimise the risk of subsequent CVD.

Comparing patient and informant ratings of depressive symptoms in various stages of Alzheimer's disease

OBJECTIVE

Using a multimethod approach, this study assessed the relationship between patient and informant ratings of depression in Alzheimer's disease (AD) in a manner that better represents the progressive course of AD, and allows for elucidation of specific cognitive domains that may explain changes in respondent agreement.

METHOD

Case data (N = 16,297) were provided by the National Alzheimer's Coordinating Center (NACC). A series of contingency analyses were performed to assess the relationship between patient and informant agreement across levels of impairment in individuals with AD. Patients and informants were placed into groups (i.e., not impaired, mild impairment, moderate impairment, severe impairment) based on patients' performance on multiple indicators of global cognitive functioning, as well as measures of attention, working memory, processing speed, executive functioning, language, and episodic learning and memory.

RESULTS

Across measures, greater impairment was significantly (p < .001) associated with decreases in patient-informant congruence and increases in rates of patients denying depression when informants endorsed observing features of the same. These inconsistencies were most pronounced in the mildest stages of impairment. For a subset of the sample, rates of patients reporting depressive symptoms when informants denied observing the same also increased alongside worsening impairment. Incremental impairment in episodic learning (χ² = 805.25) and memory (χ² = 856.94) performance were most closely associated with decreases in respondent agreement. Patient-informant relationship type did not appear to mediate the response patterns observed.

CONCLUSIONS

Mild impairment in AD patients, particularly in episodic learning and memory functioning, is significantly associated with decreases in patient-informant agreement regarding the presence of depressive symptoms. These results suggest that even at the earliest stages of AD informant reports should be used to corroborate patients' reporting. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Spatial distribution of water quality in the Amazonian region: implications for drinking water treatment procedures

Riparian communities in the Amazon suffer from water-borne diseases due to the lack of adequate water treatment capabilities. Therefore, small local water treatment plants are necessary, but the selection of treatment procedures depends largely on the physico-chemical characteristics of the water. The aim of the present research was to evaluate the physico-chemical characteristics of the water in the Amazon River and its tributaries, in order to determine customized processes for water treatment. Data from 54 fluviometric monitoring stations were organized and used to construct distribution maps. The parameters such as pH, electrical conductivity, and the concentration of suspended matter, turbidity and flow rates were evaluated. Results showed that pH was very acidic (4-5) in the northwestern portion of the region while conductivity was quite low in the entire Amazonian region (<140 μS cm^-1). Both parameters were strongly influenced by geological settings and sources of organic matter. Suspended matter and turbidity were affected by weathering processes. It was concluded that considering the acidity of the waters, mechanical procedures like filtration or slow settling should be applied to remove suspended matter rather than chemical procedures. For disinfection, instead of chemicals, solar energy should be applied.

Physical activity modifies the association between depression and cognitive function in older adults

OBJECTIVE

To examine the effects of gender and physical activity on the interplay between depression and cognitive function in late adulthood.

METHOD

Data on physical activity, depressive symptoms, two measures of cognitive function (the Animal Fluency Test (AFT) and the Digital Symbol Substitution Test (DSST)), and other demographic characteristics were extracted from 2604 adults aged ≥ 60 years participating in the National Health and Nutrition Examination Survey (2011-2014). Gender-specific multiple linear regressions examined the relationship between depressive symptoms and cognitive function in the overall sample and stratified by level of leisure-time physical activity.

RESULTS

Sample included 1327 women and 1277 men (mean age 69.0 years), Women with moderate to severe depressive symptoms had a 1.7 (95% CI: 0.5-2.9) point lower score on the AFT than those with none or minimal depressive symptoms. No such association was observed in men. In the stratified analyses, lower AFT test scores only persisted among women who were inactive. With respective to the DSST, lower test scores were observed in both men (-7.2, 95% CI: -13.1 to -1.3) and women (-6.4, 95% CI: -11.8 to -1.1) with moderate to severe depressive symptoms. In the stratified analyses, this association persisted in those who were insufficiently active, but attenuated to null among those engaged in sufficient physical activity.

CONCLUSIONS

Moderate-to-vigorous physical activity modifies the depression-cognition relationship and preserves cognition function. Engaging in sufficient (150 min/week) leisure-time physical activity at moderate-to-vigorous intensity may protect those with depressive symptoms from cognitive decline in older age.

Financial transfers from adult children and depressive symptoms among mid-aged and elderly residents in China - evidence from the China health and retirement longitudinal study

BACKGROUND

Although the awareness of mental health problems in late life is rising, the association between financial transfers to the older generations from children and mental health at older ages in China has received little attention. This study examines the association between financial transfers from children and depressive symptoms among the mid-aged and elderly residents (from 45 years of age and older) in China.

METHODS

We used the data from the China Health and Retirement Longitudinal Study (CHARLS, 2013) (n = 10,935) This included data on financial transfers from all non-co-resident children to their parents, and the individual scores on depressive symptoms as measured by the 10-item Center for Epidemiologic Studies-Depression Scale (CESD-10). A two-level - individual and community levels - mixed linear model was deployed to explore their association.

RESULTS

Financial transfers from children to parents was the major component of inter-generational financial transfers in Chinese families. A higher financial support from non-co-resident children was signivicantly and positively related to fewer depressive symptoms (coef. = - 0.195,P-value< 0.001) among both the mid-aged and elderly parents.

CONCLUSIONS

Financial transfers from non-co-resident children are associated with depressive symptoms among mid-aged and elderly residents in the China situation. Taxation and other policy measures should encourage and facilitate these type of financial transfers and prevent a decrease of support from children to parents.

Volumetric modeling of two sludge piles from water treatment plants in a Brazilian reservoir

Water treatment plants are designed to continuously produce drinkable water, meeting defined criteria of potability. However, besides potable water, these plants produce sludges that are disposed of in the environment. The present work aimed to evaluate the sludges generated in two water treatment plants and disposed of in the margin of the Juturnaíba dam. Since alum has been used as a flocculating agent in these two plants, the concentrations of aluminum were measured in the sludges and in surface sediments. The generated piles are extremely soft to walk on and difficult to measure, so indirect modeling procedures had to be applied. The calculated mass of the sludge piles at each plant are similar and respectively 60,370 and 61,479 tons. The aluminum content of the residues, calculated according to its dosage, was 33.2 and 32.6 g kg^-1 in the piles from the two plants. The amount of alum dosed to the water corresponds almost to the excess of aluminum in the sludge, compared to the sediments. It was concluded that regardless of the fact that residues are disposed of in very restricted areas, they are directly in contact with the water and may constitute a threat for the environment and humans' health.

Profiling microRNA from Brain by Microarray in a Transgenic Mouse Model of Alzheimer's Disease

MicroRNAs (miRNAs) are small noncoding RNAs, which regulate numerous cell functions by targeting mRNA for cleavage or translational repression, and have been found to play an important role in Alzheimer's disease (AD). Our study aimed to identify differentially expressed miRNAs in AD brain as a reference of potential therapeutic miRNAs or biomarkers for this disease. We used amyloid precursor protein (APP) and presenilin 1 (PS1) double transgenic mice and age-matched wild-type (WT) littermates to determine the expression of miRNAs in the brain. MiRNAs were profiled by microarray, and differentially expressed miRNAs underwent target prediction and enrichment analysis. Microarray analysis revealed 56 differentially expressed miRNAs in AD mouse brain, which involved 39 miRNAs that were significantly upregulated and 19 that were downregulated at different ages. Among those miRNAs, a total of 11 miRNAs, including miR-342-3p, miR-342-5p, miR-376c-3p, and miR-301b-3p, were not only conserved in human but also predicted to have targets and signaling pathways closely related to the pathology of AD. In conclusion, in this study, differentially expressed miRNAs were identified in AD brain and proposed as biomarkers, which may have the potential to indicate AD progression. Despite being preliminary, these results may aid in investigating pathological hallmarks and identify effective therapeutic targets.

Cognitive behavioral therapy (CBT) for preventing Alzheimer's disease

This review provides the rationale for implementing cognitive behavioral therapy (CBT) for the prevention of Alzheimer's disease (AD). There are known risk factors associated with the development of AD, some of which may be ameliorated with CBT. We posit that treating the risk factors of inactivity, poor diet, hyposmia and anosmia, sleep disorders and lack of regularly engaged challenging cognitive activity will modify the physiology of the brain sufficiently to avoid the accumulation of excess proteins, including amyloid beta, causal events in the development of AD. Further, the successful treatment of the listed risk factors is well within our technology to do so and, even further, it is cost effective. Also, there is considerable scientific literature to support the proposition that, if implemented by well-established practices, CBT will be effective and will be engaged by those of retirement age. That is, we present a biologically informed CBT for the prevention of the development of AD, i.e., an aspect of applied behavioral neuroscience.