Is the relationship between syndromes of depression and dementia temporal? The MRC-ALPHA and Hefei-China studies

Analysis of Risk Factors for Cognitive Dysfunction in Disabled Elderly Patients in Chengdu, China

Background

With the aging population comes an increase in functional disability that leads to dependency and institutionalization, as well as social, medical, and economic challenges. This study aimed to classify and assess the factors affecting cognitive deficits in disabled elderly people.

Material/Methods

Disabled patients ≥60 years old were assessed by face-to-face cross-sectional surveys, which were conducted using advanced peer-to-peer software. The ability to perform daily life tasks was assessed using the Modified Barthel Index. Cognitive function was evaluated with the Mini-cognitive assessment instrument. Using these surveys, 9471 individuals were included in this study. The rank-sum test was used to investigate differences between groups. Disordered multi-class logistic regression was used to correct related confounding factors for multivariate analysis.

Results

The ratios of normal cognitive function, cognitive impairment, and dementia were 3.71%, 38.59%, and 57.70%, respectively. The univariate analysis and multivariate analysis showed that older individuals (≥80 years), women, illiterate individuals, and lonely persons were more prone to dementia. Moreover, a history of hypertension, diabetes, osteoporosis, and fractures were significantly associated with dementia.

Conclusions

The proportion of dementia in the elderly disabled patients is very high (57.7%) in Chengdu City. Age (≥80 years), female sex, education level (illiterate individuals), living conditions, and chronic disease were closely correlated with cognitive functions.

Mid-life socioeconomic status, depressive symptomatology and general cognitive status among older adults: inter-relationships and temporal effects

Background

Few longitudinal studies have analyzed how socioeconomic status (SES) influences both depressive and cognitive development over an individual’s life course. This study investigates the change trajectories of both depressive symptomatology and general cognitive status, as well as their associations over time, focusing on the effects of mid-life SES.

Methods

Data were obtained from the Taiwan Longitudinal Study on Aging (1993–2007), a nationally representative cohort study of older adults in Taiwan. The short form of the Center of Epidemiological Studies-Depression (CES-D) scale that measures depressive symptomatology in two domains (negative affect and lack of positive affect) was used. General cognitive status was assessed using the brief Short Portable Mental Status Questionnaire scale. Assessments of the subjects’ mid-life SES included measurement of the participant’s education and occupation. Analyses were conducted by the parallel latent growth curve modeling.

Results

The participants’ initial levels of depressive symptomatology and general cognitive status were significantly and negatively correlated; furthermore, any changes in these two outcomes were also correlated over time. The initial assessment of general cognitive status significantly contributed to any advancement towards more severe depressive symptomatology over time, particularly when this occurred in a negative manner. Furthermore, a mid-life SES advantage resulted in a significant reduction in late-life depressive symptomatology and also produced a slower decline in general cognitive status during later life. In contrast, lower mid-life SES exacerbated depressive symptomatology during old age, both at the initial assessment and in terms of the change over time. In addition, female gender was significantly associated with lower general cognitive status and more severe depressive symptomatology in negative affect.

Conclusions

These findings suggest a complex and longitudinal association between depressive symptomatology and general cognitive status in later life and this complicated relationship seems to be affected by mid-life SES over time.

Socioeconomic deprivation and survival after stroke in China: a systematic literature review and a new population-based cohort study

OBJECTIVE

To assess the association of socioeconomic deprivation (SED) with survival after stroke in China.

DESIGN

A systematic literature review and a new population-based cohort study.

SETTING AND PARTICIPANTS

In urban and rural communities in Anhui, China, 2978 residents aged ≥60 years took part in baseline investigation and were followed up for 5 years; five published studies were identified for a systematic review.

PRIMARY AND SECONDARY OUTCOME MEASURES

167 of 2978 participants (5.6%) had doctor-diagnosed stroke at baseline or 1 year later. All-cause mortality in the follow-up.

RESULTS

In the Anhui cohort follow-up of 167 patients with stroke, 64 (38.3%) died. Multivariate adjusted hazard ratio (HR) of mortality in patients with educational level of less than or equal to primary school was 1.88 (95% CI 1.05 to 3.36) compared to those having more than primary school education. Increased HR of mortality in patients living in a rural area was at borderline significant (1.64, 0.97 to 2.78), but the HR in patients with lower levels of occupation and income was not significant. Published studies showed a significant increase in stroke mortality in relation to some SED indicators. Pooled relative risk (RR) of mortality in patients with low education was 3.07 (1.27 to 7.34), in patients with low income 1.58 (1.50 to 1.65) and in patients living in rural areas 1.47 (1.37 to 1.58).

CONCLUSIONS

The evidence suggests the presence of a mortality gradient after stroke for material as well as social forms of deprivation in China. Inequalities in survival after stroke persist and need to be taken into account when implementing intervention programmes.

Socioeconomic status and survival among older adults with dementia and depression

BACKGROUND

People from lower socioeconomic groups have a higher risk of mortality. The impact of low socioeconomic status on survival among older adults with dementia and depression remains unclear.

AIMS

To investigate the association between socioeconomic status and mortality in people with dementia and late-life depression in China.

METHOD

Using Geriatric Mental Status - Automated Geriatric Examination for Computer Assisted Taxonomy (GMS-AGECAT) we interviewed 2978 people aged ⩾60 years in Anhui, China. We characterised baseline socioeconomic status and risk factors and diagnosed 223 people with dementia and 128 with depression. All-cause mortality was followed up over 5.6 years.

RESULTS

Individuals with dementia living in rural areas had a three times greater risk of mortality (multivariate adjusted hazard ratio (HR) = 2.96, 95% CI 1.45-6.04) than those in urban areas, and for those with depression the HR was 4.15 (95% CI 1.59-10.83). There were similar mortality rates when comparing people with dementia with low v. high levels of education, occupation and income, but individuals with depression with low v. high levels had non-significant increases in mortality of 11%, 50% and 55% respectively

CONCLUSIONS

Older adults with dementia and depression living in rural China had a significantly higher risk of mortality than urban counterparts. Interventions should be implemented in rural areas to tackle survival inequality in dementia and depression.

Determinants for undetected dementia and late-life depression

BACKGROUND

Determinants for undetected dementia and late-life depression have been not well studied.

AIMS

To investigate risk factors for undetected dementia and depression in older communities.

METHOD

Using the method of the 10/66 algorithm, we interviewed a random sample of 7072 participants aged ≥60 years in six provinces of China during 2007-2011. We documented doctor-diagnosed dementia and depression in the interview. Using the validated 10/66 algorithm we diagnosed dementia (n = 359) and depression (n = 328).

RESULTS

We found that 93.1% of dementia and 92.5% of depression was undetected. Both undetected dementia and depression were significantly associated with low levels of education and occupation, and living in a rural area. The risk of undetected dementia was also associated with 'help available when needed', and inversely, with a family history of mental illness and having functional impairment. Undetected depression was significantly related to female gender, low income, having more children and inversely with having heart disease.

CONCLUSIONS

Older adults in China have high levels of undetected dementia and depression. General socioeconomic improvement, associated with mental health education, targeting high-risk populations are likely to increase detection of dementia and depression in older adults, providing a backdrop for culturally acceptable service development.

Depression and cognition: how do they interrelate in old age?

OBJECTIVES

To disentangle the reciprocal effects between depressive symptoms and cognitive functioning over time and to study the association between changes in their trajectories using 13 years of follow-up.

DESIGN AND PARTICIPANTS

Data were used from five waves of the population-based Longitudinal Aging Study Amsterdam. Subjects were included if data was present on depressive symptoms and cognitive performance on at least two occasions, which resulted in a study sample of N = 2,299.

MEASUREMENTS

Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale. Cognitive functioning was assessed using the Mini-Mental State Examination (general cognitive functioning) and timed coding task (speed of information processing).

RESULTS

Cross-domain latent change analyses showed that depression at baseline predicted both decline of general cognitive functioning and information processing speed, independent of relevant covariates. Conversely, information processing speed at baseline, but not general cognitive functioning was related to the course of depressive symptoms. The course of cognitive functioning was not significantly associated with the course of depressive symptoms.

CONCLUSION

Depressive symptoms in older patients flag an increased likelihood of cognitive decline. This effect is considerable and may be due to several underlying mechanisms. The likelihood of the relationship reflecting either a causal effect of depression on cognitive decline, or a common cause, or both, should be estimated. Likewise, older persons with more limitations in information processing speed specifically are more vulnerable to increases in depression.

Predictors of diabetes in older people in urban China

BACKGROUND

China has the largest number of people with diabetes in the world. Over the last 30 years China has experienced rapid economic growth and a growing income gap between rich and poor. The population is ageing, however diabetes in older people has not been well studied to date. In this study we determined incidence and predictors of diabetes in older Chinese people.

METHODS

During 2001, using a standard interview method, we examined 1,317 adults aged ≥65 years who did not have diabetes in the city of Hefei, and characterized baseline risk factors. Over 7.5 years of follow up, we documented incident diabetes using self-reported doctor diagnosis and the cause of death in the whole cohort, and HbA(1C) ≥48 mmol/mol in a nested case-control sample. A multivariate Cox regression model was employed to investigate risk of diabetes in relation to baseline risk factors.

RESULTS

During follow up, 119 persons had newly diagnosed diabetes. World age-standardised incidence of diabetes was 24.5 (95% CI 19.5-29.5) per 1,000 person-years. Risk of diabetes was significantly and positively associated with income, waist circumference and body mass index, smoking and uncontrolled hypertension, but negatively associated with having a hobby of walking and frequency of visiting children/other relatives and contacting neighbours/friends. Higher income was significantly associated with increased diabetes risk regardless of cardiovascular and psychosocial risk factors. Compared to those with middle income and no psychosocial risk factors, the hazard ratio for incident diabetes among participants with high income and psychosocial risk was 2.13 (95% CI 1.02-4.45).

CONCLUSIONS

Increasing incidence of diabetes in relation to high income has become an important public health issue in China. Maintaining social networks and gentle physical activities and reducing psychosocial factors may be integrated into current multi-faceted preventive strategies for curbing the epidemic of diabetes in the older population.

Association between environmental tobacco smoke exposure and dementia syndromes

OBJECTIVES

Environmental tobacco smoke (ETS) has a range of adverse health effects, but its association with dementia remains unclear and with dementia syndromes unknown. We examined the dose-response relationship between ETS exposure and dementia syndromes.

METHODS

Using a standard method of GMS, we interviewed 5921 people aged ≥60 years in five provinces in China in 2007-2009 and characterised their ETS exposure. Five levels of dementia syndrome were diagnosed using the Automated Geriatric Examination for Computer Assisted Taxonomy instrument. The relative risk (RR) of moderate (levels 1-2) and severe (levels 3-5) dementia syndromes among participants exposed to ETS was calculated in multivariate adjusted regression models.

RESULTS

626 participants (10.6%) had severe dementia syndromes and 869 (14.7%) moderate syndromes. Participants exposed to ETS had a significantly increased risk of severe syndromes (adjusted RR 1.29, 95% CI 1.05 to 1.59). This was dose-dependently related to exposure level and duration. The cumulative exposure dose data showed an adjusted RR of 0.99 (95% CI 0.76 to 1.28) for >0-24 level years of exposure, 1.15 (95% CI 0.93 to 1.42) for 25-49 level years, 1.18 (95% CI 0.87 to 1.59) for 59-74 level years, 1.39 (95% CI 1.03 to 1.84) for 75-99 level years and 1.95 (95% CI 1.34 to 2.83) for ≥100 level years. Significant associations with severe syndromes were found in never smokers and in former/current smokers. There were no positive associations between ETS and moderate dementia syndromes.

CONCLUSIONS

ETS should be considered an important risk factor for severe dementia syndromes. Avoidance of ETS may reduce the rates of severe dementia syndromes worldwide.

A multicentre community-based study of dementia cases and subcases in older people in China--the GMS-AGECAT prevalence and socio-economic correlates

BACKGROUND

Previous studies indicated overall relatively low prevalence of dementia in older people in China, which may be biased by studied samples or methods. We determined the prevalence of dementia cases and subcases in China and examined their socio-economic correlates.

METHODS

Using the Geriatric Mental State interview, we examined random samples of 2917 participants aged ≥ 65 years in urban and rural Anhui, China in 2001-2003, and 3327 in four other provinces in 2008-2009. Dementia cases and subcases were diagnosed by Geriatric Mental State-Automated Geriatric Examination for Computer Assisted Taxonomy.

RESULTS

Age-standardised prevalence for cases and subcases of dementia in the Anhui elders was 7.20% (95%CI 6.29%-8.20%) and 10.5% (9.38%-11.6%), and in the four provinces, 9.86% (8.80%-10.9%) and 8.51% (7.51%-9.52%). The matched figures among the participants who were literate were 3.05% (2.08%-4.02%) and 10.0% (8.38%-11.6%), and 4.92% (3.89%-5.96%) and 6.76% (5.55%-7.96%), respectively. There were higher prevalence rates of dementia cases and subcases in the rural elders than in the urban. Both the Anhui and four-province studies showed an obvious association of dementia with higher and lower incomes among elders who had lower educational levels or had the lowest occupational class. The highest risk of dementia was found in those who were illiterate but had the highest income or had the job of business/nonmanual labouring.

CONCLUSIONS

People in China have a higher prevalence of dementia than previously reported. Its U-shaped relationship with income and the excess subcases prevalence predicates a significant burden of disease, both now and for the future, suggesting preventive strategy for dementia in China.