Delaying dementia and nursing home placement: the Dubbo study of elderly Australians over a 14-year follow-up

What have observational studies taught us about brain health? An exploration of select cardiovascular risks and cognitive function

Observational research studies serve as the cornerstone for gathering evidence on risk factors and contributors to cognitive decline and impairment. The evidence can then be combined with data from preclinical studies and randomized controlled trials to ultimately inform the development of effective interventions and the content of guidance statements. Observational cohort designs on modifiable risk factors and brain health can be particularly beneficial for studying questions that are unethical or impractical for a clinical trial setting, associations with dementia which may develop over decades, and underrepresented populations typically not included in clinical trials. This chapter will review the major observational, epidemiologic studies pertaining to the traditional vascular risk factors - hypertension, diabetes mellitus, hypercholesterolemia, smoking, and physical inactivity - and how they may impact brain health.

Gardening and subjective cognitive decline: a cross-sectional study and mediation analyses of 136,748 adults aged 45+ years

BACKGROUND

Given the benefits of gardening for physical and psychological health, we explored whether gardening was associated with lower risks of subjective cognitive decline (SCD), a precursor of dementia, and SCD-related functional limitations.

METHODS

Included in this cross-sectional study were 136,748 participants aged 45 + years old from the Behavioral Risk Factor Surveillance System 2019 survey, who were then categorized into three groups according to self-reported exercise status: non-exercisers, gardeners, and other exercisers. SCD was assessed via a questionnaire, and SCD-related functional limitations were referred to as having difficulties in engaging in household or social activities due to SCD. The odds ratio (OR) and 95% confidence interval (CI) were calculated to assess the associations of gardening with SCD and SCD-related functional limitations, adjusted for age, sex, socioeconomic status, lifestyle factors, and health status. Mediation analyses were conducted to examine whether the observed association between gardening and SCD was mediated by energy expenditure (MET-hours/week), depression status, and consumption of fruits and vegetables.

RESULTS

Overall, 11.1% and 5.4% of participants self-reported experiencing SCD and SCD-related functional limitations, respectively. The adjusted OR for gardeners vs. non-exercisers, was 0.72 (95% CI 0.62-0.83) for SCD and 0.57 (95% CI 0.44-0.73) for SCD-related functional limitations. The observed association between gardening and SCD was explained by higher energy expenditure (39.0%), lower likelihood of having depression (21.5%), and higher consumption of fruits and vegetables (3.4%) (P<0.05 for all). Similar patterns were observed for SCD-related functional limitations.

CONCLUSION

In this nationally representative sample, gardening was associated with better cognitive status, which may be mainly attributed to better depression status and energy expenditure.

Residential greenness and risk of incident dementia: A prospective study of 375,342 participants

INTRODUCTION

Incorporation of greenspace may be a novel environmental policy that might result in positive health effects; hence, this study aimed to investigate the association between residential greenness and dementia incidence. The effects of particulate air pollution on mediating dementia were also determined.

METHODS

A prospective cohort study involving 375,342 UK biobank participants was conducted, in which Cox regression models were used to determine the association of greenspace exposure with the risks of all-cause dementia (ACD), Alzheimer's disease (AD) and vascular dementia (VD). Sociodemographic variables, lifestyle or dietary characteristics and apolipoprotein E4 status were controlled using two levels of adjusted models. Mediation analyses were performed to determine the mediation effects of PMs.

RESULTS

The results indicated that there were 4929 ACD, 2132 AD, and 1184 VD incidents throughout the 8-year study. In the multi-adjusted model, each interquartile increment in greenspace (buffer 300m) conferred the lower risks of ACD (HR = 0.968, 95% confidence intervals [CI]: 0.938-1.000]) and VD (HR = 0.926, 95% CI: 0.867-0.989). The fourth greenspace quartile conferred also reduced risks of ACD (HR = 0.891, 95% CI: 0.804-0.989) and VD (HR = 0.778, 95% CI: 0.630-0.960) in reference to the first quartile. With regard to 1000m catchment, each interquartile increment conferred a 5.0% (95% CI: 1.8-8.1) lower risk of ACD, and the fourth greenspace quartile conferred a 10.9% (95% CI: 0.9-19.8) lower risk of ACD compared to the first quartile. The protective effect of greenness might be mediated based on the reduction of PM_2.5 and PM₁₀ (P_{indirect effect}<0.05).

CONCLUSIONS

Increasing greenness reduces the risk of dementia. This study suggests that greenspace is an environmental strategy that helps prevent dementia.

Neighborhood greenspace exposure as a protective factor in dementia risk among U.S. adults 75 years or older: a cohort study

BACKGROUND

Research suggests that greenspace may confer neurocognitive benefits. This study examines whether residential greenspace is associated with risk of dementia among older adults.

METHODS

Greenspace exposure was computed for 3047 participants aged 75 years and older enrolled in the Gingko Evaluation of Memory Study (GEMS) across four U.S. sites that prospectively evaluated dementia and its subtypes, Alzheimer's disease (AD), vascular dementia (VaD), and mixed pathologies, using neuropsychiatric evaluations between 2000 and 2008. After geocoding participant residences at baseline, three greenspace metrics-Normalized Difference Vegetative Index, percent park overlap within a 2-km radius, and linear distance to nearest park-were combined to create a composite residential greenspace measure categorized into tertiles. Cox proportional hazards models estimated the associations between baseline greenspace and risk of incident all-cause dementia, AD, and Mixed/VaD.

RESULTS

Compared to low residential greenspace, high residential greenspace was associated with a reduced risk of dementia (HR = 0.76 95% CI: 0.59,0.98) in models adjusted for multiple covariates. After additional adjustment for behavioral characteristics, Apolipoprotein E ɛ4 status, and other covariates, the association was slightly attenuated (HR = 0.82; 95% CI:0.63,1.06). Those exposed to medium levels of greenspace also had 28% lower risk (HR = 0.72; CI: 0.55, 0.95) of dementia compared to those with low greenspace in adjusted models. Subtype associations between high residential greenspace and AD were not statistically significant. Greenspace was not found to be significantly associated with mixed/vascular pathologies.

CONCLUSIONS

This study showed evidence for an association between residential greenspace and all-cause dementia among older adults. Future research with larger sample size, precise characterization of different dementia subtypes, and assessment of residential greenspace earlier in life may help clarify the role between exposure to greenspace and dementia risk.

Impact of various intensities and frequencies of non-occupational physical activity on the risk of dementia among physically independent older adults: the Japan Gerontological Evaluation Study

OBJECTIVES

The aim of this study was to investigate the association between different intensities and frequencies of non-occupational physical activity (PA) and the risk of dementia among Japanese older adults.

STUDY DESIGN

This was a prospective cohort study.

METHODS

A total of 2194 participants aged ≥65 years from the Japan Gerontological Evaluation Study were followed up between 2010 and 2016. The standardised dementia scale of the long-term care insurance system was used to identify incident dementia, whereas non-occupational PA (<2 or ≥2 times/week on each intensity: light, moderate and vigorous) was assessed using a questionnaire. Cox regression was used to compute the hazard ratios (HRs) and 95% confidence intervals (CIs) for incident dementia.

RESULTS

After adjustment for sociodemographic and medical characteristics, the following frequencies and intensities of non-occupational PA, compared with no non-occupational PA at all, were associated with a reduced risk of dementia: light PA ≥2 times/week (HR = 0.61, 95% CI: 0.38-0.97), moderate PA <2 times/week (HR = 0.46, 95% CI: 0.28-0.76), moderate PA ≥2 times/week (HR = 0.57, 95% CI: 0.36-0.91), vigorous PA <2 times/week (HR = 0.40, 95% CI: 0.21-0.74) and vigorous PA ≥2 times/week (HR = 0.29, 95% CI: 0.15-0.57). In the sex-specific analysis, moderate PA <2 times/week and vigorous PA ≥2 times/week were associated with a reduced risk of dementia in men, whereas light and moderate PA ≥2 times/week and all frequencies of vigorous PA were associated with a reduced risk of dementia in women.

CONCLUSIONS

Practicing non-occupational PA was associated with a reduced risk of dementia among Japanese older adults.

Life Course Nature Exposure and Mental Health Outcomes: A Systematic Review and Future Directions

Recently, an emerging body of literature has examined the relationships between early life nature exposure and mental health in later life; however, no critical synthesis yet exists regarding the extent and strength of these relationships. This study presents the first systematic review of studies in this growing area. Following the PRISMA framework, we searched six databases (i.e., Scopus, Web of Science, MEDLINE, Embase, PsycINFO, and CINAHL); conducted identification, screening, eligibility, and inclusion analyses; and identified a final set of 29 articles. The review set comprises primarily longitudinal studies, with several cross-sectional studies using retrospective measures of childhood nature exposure. The majority of included studies were published between 2016 and 2020 and conducted in Europe and North America. Five domains of mental health outcomes are associated with early-life nature exposure: incidence of mental disorders, psychiatric symptoms and emotions, conduct problems in children, cognitive function, and subjective well-being. The evidence lends support to an overall beneficial role of early nature exposure on mental health, although inconsistencies are reported. Taken together, the evidence does not suggest that exposure at any given life stage is more saliently associated with mental health outcomes than at others. We discuss the validity concerns and methodological remedies and offer directions for future research.

Urban green space, tree canopy and 11-year risk of dementia in a cohort of 109,688 Australians

INTRODUCTION

Urban greening is a climate change-related policy with considerable health benefits. But do these benefits extend to prevention of dementia and, if so, which types of green space matter?

METHOD

Multilevel discrete time-to-event cohort study of incident Alzheimer's disease over 11 years among a baseline recruited between January 1, 2006 and December 31, 2009 (the Sax Institute's 45 and Up Study). Sampled participants for this study (N=109,688) were aged 45 years or older with no record of dementia up to 6 years before baseline, living in the cities of Sydney, Wollongong and Newcastle, Australia. Exposures were percentage total green space, tree canopy and open grass within 1.6-km road network distance buffers at baseline. Outcomes were time-to-first anti-dementia medication prescription (Department of Human Services) or dementia detected during hospitalisation or death up to 31 December 2016 (up to 11 years follow-up). Outcomes were analysed in parallel to triangulate on associations with green space, while testing for bias due to potential under-prescribing of anti-dementia medications. Models were adjusted for baseline person-level factors and area-level socioeconomic disadvantage.

RESULTS

Dementia detection varied by case ascertainment method. 1.55% (1,703/109,688) persons were detected using prescribed anti-dementia medications. 3.32% (3,639/109,688) persons were detected during hospitalisation or death via ICD-10 codes. Dementia incidence irrespective of outcome measurement was lower among females, younger participants, those living in couples, with higher qualifications and higher incomes. Dementia risk was lower with more tree canopy when the outcome was measured using hospital and death records (≥30% vs <10% tree canopy incidence hazard ratio (IHR) = 0.86, 95%CI 0.75, 0.99), after adjusting for person-level factors. The opposite association was observed when anti-dementia medications were used to detect dementia (≥30% vs <10% tree canopy IHR = 1.33, 95%CI 1.07, 1.66). Anti-dementia medication-based detection also indicated lower dementia risk with more open grass (≥20% vs <5% IHR = 0.83, 95%CI 0.67, 1.03). Anti-dementia medication prescribing was lower in the highest vs. lowest area-level disadvantage tertile (29.8% vs. 43.7%) among people diagnosed with dementia, indicating potential bias from geographic differences in prescribing practices. Adjusting for area-level disadvantage explained associations between tree canopy, open grass and dementia when detected by anti-dementia medication, but had negligible impact on negative (i.e. potentially protective) association between tree canopy and dementia detected by hospital and death records (≥30% vs <10% tree canopy hazard ratio 0.84, 95%CI 0.72, 0.99).

CONCLUSIONS

Increasing urban tree canopy cover may help to reduce the risk of dementia. Replication in contrasting contexts and mediation studies to assess pathways are warranted.

Association Between the Activity Space Exposure to Parks in Childhood and Adolescence and Cognitive Aging in Later Life

The exposure to green space in early life may support better cognitive aging in later life. However, this exposure is usually measured using the residential location alone. This disregards the exposure to green spaces in places frequented during daily activities (i.e., the ‘activity space’). Overlooking the multiple locations visited by an individual over the course of a day is likely to result in poor estimation of the environmental exposure and therefore exacerbates the contextual uncertainty. A child’s activity space is influenced by factors including age, sex, and the parental perception of the neighborhood. This paper develops indices of park availability based on individuals’ activity spaces (home, school, and the optimal route to school). These measures are used to examine whether park availability in childhood is related to cognitive change much later in life. Multi-level linear models, including random effects for schools, were used to test the association between park availability during childhood and adolescence and cognitive aging (age 70 to 76) in the Lothian Birth Cohort 1936 participants (N = 281). To test for the effect modification, these models were stratified by sex and road traffic accident (RTA) density. Park availability during adolescence was associated with better cognitive aging at a concurrently low RTA density (β = 0.98, 95% CI: 0.36 to 1.60), but not when the RTA density was higher (β = 0.22, 95% CI: −0.07 to 0.51). Green space exposure during early life may be important for optimal cognitive aging; this should be evidenced using activity space-based measures within a life-course perspective.

Residential Surrounding Greenness and Cognitive Decline: A 10-Year Follow-up of the Whitehall II Cohort

BACKGROUND

Evidence on beneficial associations of green space with cognitive function in older adults is very scarce and mainly limited to cross-sectional studies.

OBJECTIVES

We aimed to investigate the association between long-term residential surrounding greenness and cognitive decline.

METHODS

This longitudinal study was based on three waves of data from the Whitehall II cohort, providing a 10-y follow-up (1997-1999 to 2007-2009) of 6,506 participants (45-68 y old) from the United Kingdom. Residential surrounding greenness was obtained across buffers of 500 and around the participants' residential addresses at each follow-up using satellite images on greenness (Normalized Difference Vegetation Index; NDVI) from a summer month in every follow-up period. Cognitive tests assessed reasoning, short-term memory, and verbal fluency. The cognitive scores were standardized and summarized in a global cognition z-score. To quantify the impact of greenness on repeated measurements of cognition, linear mixed effect models were developed that included an interaction between age and the indicator of greenness, and controlled for covariates including individual and neighborhood indicators of socioeconomic status (SES).

RESULTS

In a fully adjusted model, an interquartile range (IQR) increase in NDVI was associated with a difference in the global cognition z-score of 0.020 [95% confidence interval (CI): 0.003, 0.037; p=0.02] in the 500-m buffer and of 0.021 (95% CI: 0.003, 0.039; p=0.02) in the 1,000-m buffer over 10 y. The associations with cognitive decline over the study period were stronger among women than among men.

CONCLUSIONS

Higher residential surrounding greenness was associated with slower cognitive decline over a 10-y follow-up period in the Whitehall II cohort of civil servants. https://doi.org/10.1289/EHP2875.

Pilot Randomized Controlled Trial of a Home Vegetable Gardening Intervention among Older Cancer Survivors Shows Feasibility, Satisfaction, and Promise in Improving Vegetable and Fruit Consumption, Reassurance of Worth, and the Trajectory of Central Adiposity

BACKGROUND

Holistic approaches are sought to improve lifestyle behaviors and health of cancer survivors long term.

OBJECTIVE

Our aim was to explore whether a home-based vegetable gardening intervention is feasible and whether it improves diet and other health-related outcomes among older cancer survivors.

DESIGN

We conducted a feasibility trial in which cancer survivors were randomized to receive a year-long gardening intervention immediately or to a wait-list control arm. Home visits at baseline and 1 year assessed physical performance, anthropometric indices, behavioral and psychosocial outcomes, and biomarkers.

PARTICIPANTS/SETTING

Participants included 46 older (aged 60+ years) survivors of locoregionally staged cancers across Alabama from 2014 to 2016. Forty-two completed 1-year follow-up.

INTERVENTION

Cooperative extension master gardeners delivered guidance to establish three seasonal vegetable gardens at survivors' homes. Plants, seeds, and gardening supplies were provided.

OUTCOMES

Primary outcomes were feasibility targets of 80% accrual and retention, and an absence of serious adverse events; other outcomes were secondary and explored potential benefits.

STATISTICAL ANALYSES

Baseline to follow-up changes were assessed within and between arms using paired t, McNemar's, and χ² tests.

RESULTS

This trial proved to be safe and demonstrated 91.3% retention; 70% of intervention participants rated their experience as "excellent," and 85% would "do it again." Data suggest significantly increased reassurance of worth (+0.49 vs -0.45) and attenuated increases in waist circumference (+2.30 cm vs +7.96 cm) in the gardening vs control arms (P=0.02). Vegetable and fruit consumption increased by approximately 1 serving/day within the gardening arm from baseline to follow-up (mean [standard error]=1.34 [1.2] to 2.25 [1.9] servings/day; P=0.02)] compared to controls (1.22 [1.1] to 1.12 [0.7]; P=0.77; between-arm P=0.06).

CONCLUSIONS

The home vegetable gardening intervention among older cancer survivors was feasible and suggested improvements in vegetable and fruit consumption and reassurance of worth; data also suggest attenuated increases in waist circumference. Continued study of vegetable gardening interventions is warranted to improve health, health behaviors, and well-being of older cancer survivors.

Risk factors associated with residential aged care, respite and transitional aged care admission for older people following an injury-related hospitalisation

OBJECTIVES

To identify factors associated with admission to residential aged care (RAC), respite RAC and transitional care (TC) for older individuals following an injury hospitalisation.

METHOD

A retrospective analysis was conducted of individuals aged ≥65 years who had an injury hospitalisation and who were admitted to RAC during 1 July 2008 and 30 June 2013 in New South Wales, Australia. Multinominal logistic regression was used to examine the factors associated with admissions to aged care services compared to returning to the community.

RESULTS

Of 191,301 injury hospitalisations, 41,085 (21.5%) individuals either returned or were new admissions to long-term or respite RAC and 3,218 individuals were admitted to TC. Older individuals newly admitted to long-term RAC were four times more likely (OR: 4.36; 95%CI 4.15-4.57), those admitted to respite RAC were twice as likely (OR: 2.37; 95%CI 2.21-2.54) and people admitted to TC were less likely (OR: 0.60; 95%CI 0.53-0.68) to have dementia compared to individuals who returned to the community. Overall, individuals who were admitted to long-term or respite RAC had a higher likelihood of experiencing limitations associated with their physical, cognitive or social abilities, with individuals admitted to TC having a higher likelihood of issues with hygiene and mobility, compared to individuals returning to the community.

CONCLUSION

Understanding the profile and predictive risk factors for injured older individuals using RAC (long-term, respite or TC services) can inform current and future aged care service resource use needs and can be used to understand factors associated with service use.

Management of Relocation in Cognitively Intact Older Adults

Relocation, a major life transition that can affect health positively and negatively, is moving from one permanent home to another. Many older adults will relocate at some time during their life. Relocation is also a complex process that requires careful consideration and planning before the move (i.e., pre-location) and adjustment to the new home after the move (i.e., post-relocation). The current article is a summary of content based on a comprehensive evidence-based practice guideline focused on management of relocation in cognitively intact older adults. The guideline was designed to be used across diverse settings by nurses and other providers. Pre-relocation guidelines include assessment for the need for relocation, interventions prior to moving, and outcomes for evaluation of the pre-relocation process. For post-relocation, content focuses on assessment of risks for not adjusting after the move as well as intervention guidelines to promote adjustment and outcomes for evaluation. Implications include advocacy for older adults by using the guideline, disseminating it, and conducting future research. [Journal of Gerontological Nursing, 42(11), 14-23.].

The long-term association between physical activity and risk of dementia in the community: the Hisayama Study

We investigated the long-term influence of physical activity on the risk of dementia in an elderly Japanese population. A total of 803 community-dwelling elderly Japanese individuals without dementia aged ≥65 years were followed prospectively for 17 years. Physically active status was defined as engaging in exercise at least one or more times per week during leisure time, and participants were divided into an active group and an inactive group by the presence or absence of such physical activity. The risk estimates of physical activity on the development of all-cause dementia and its subtypes were computed using a Cox proportional hazards model. During the follow-up, 291 participants developed all-cause dementia. Of these, 165 had Alzheimer's disease (AD), 93 had vascular dementia (VaD), and 47 had other dementia. Compared with the inactive group, the active group showed significantly lower crude incidence of AD (21.8 vs. 14.2 per 1000 person-years, p = 0.01), but no significant differences were observed for all-cause dementia (35.6 vs. 30.5, p = 0.17), VaD (11.3 vs. 9.8, p = 049), and other dementia (4.6 vs. 7.1, p = 0.15). After adjusting for potential confounders, the relationship between physical activity and risk of AD remained significant (adjusted hazard ratio 0.59, 95% confidence interval 0.41-0.84, p = 0.003). Our findings suggest that physical activity reduces the long-term risk of dementia, especially AD, in the general Japanese population.

Physical and Cognitive Activities as Deterrents of Cognitive Decline in a Biracial Population Sample

OBJECTIVE

Physical and cognitive activities are associated with slower cognitive decline. Few studies have examined racial differences in these associations, however. The aim of this study was to examine the association of physical and cognitive activities with level and change in cognitive function among black and white participants. A secondary aim was to explore observed differences between black and white participants using post hoc analyses based on education and cognitive function levels.

METHODS

Data came from a longitudinal study of 7,742 (63% black and 61% female) participants assessed three times over an average of 9.5 years. At baseline, each participant reported number of hours of leisure time physical activity (categorized using quartiles) and rated frequency of participation in cognitively stimulating activities (range: 0-4). A standardized measure of cognition was derived from tests of memory, perceptual speed, and orientation.

RESULTS

Of the 7,742 participants, 2,322 (30%) reported no physical activity. Cognitive decline was slower by about 20% (95% CI: 13%-27%) among whites with physical activity above 1.25 hours compared with those with no physical activity, but showed no significant decrease in cognitive decline relative to those with no physical activity among blacks. Further post hoc analysis revealed cognitive decline to be slower by about 29% (95% CI: 20%-38%) among blacks and whites with higher education and above average baseline cognition. A 1-point increase in cognitive activity frequency decreased cognitive decline by 8% (95% CI: 3%-14%) among blacks and by 14% (95% CI: 7%-20%) among whites.

CONCLUSIONS

The benefits of higher physical activity on cognitive decline was observed among whites, and among blacks with higher education and above average baseline cognitive function. Nevertheless, the protective effect of cognitive activity seems to be independent of education and baseline cognitive function among both blacks and whites.

Does physical activity prevent cognitive decline and dementia?: A systematic review and meta-analysis of longitudinal studies

BACKGROUND

By 2050, it has been estimated that approximately one-fifth of the population will be made up of older adults (aged ≥60 years). Old age often comes with cognitive decline and dementia. Physical activity may prevent cognitive decline and dementia.

METHODS

We reviewed and synthesised prospective studies into physical activity and cognitive decline, and physical activity and dementia, published until January 2014. Forty-seven cohorts, derived from two previous systematic reviews and an updated database search, were used in the meta-analyses. Included participants were aged ≥40 years, in good health and/or randomly selected from the community. Studies were assessed for methodological quality.

RESULTS

Twenty-one cohorts on physical activity and cognitive decline and twenty-six cohorts on physical activity and dementia were included. Meta-analysis, using the quality-effects model, suggests that participants with higher levels of physical activity, when compared to those with lower levels, are at reduced risk of cognitive decline, RR 0.65, 95% CI 0.55-0.76, and dementia, RR 0.86, 95% CI 0.76-0.97. Sensitivity analyses revealed a more conservative estimate of the impact of physical activity on cognitive decline and dementia for high quality studies, studies reporting effect sizes as ORs, greater number of adjustments (≥10), and longer follow-up time (≥10 years). When one heavily weighted study was excluded, physical activity was associated with an 18% reduction in the risk of dementia (RR 0.82; 0.73-0.91).

CONCLUSIONS

Longitudinal observational studies show an association between higher levels of physical activity and a reduced risk of cognitive decline and dementia. A case can be made for a causal interpretation. Future research should use objective measures of physical activity, adjust for the full range of confounders and have adequate follow-up length. Ideally, randomised controlled trials will be conducted. Regardless of any effect on cognition, physical activity should be encouraged, as it has been shown to be beneficial on numerous levels.

Predictors of institutionalization of dementia patients in mild and moderate stages: a 4-year prospective analysis

Background

Institutionalization is the most important milestone in the care of dementia patients. This study was aimed at identifying relevant predictors of institutionalization in a broad empirical context and interpreting them on the basis of the predictor model proposed by Luppa et al. [Dement Geriatr Cogn Disord 2008;26:65-78].

Methods

At the start of this study, 357 patients with mild to moderate dementia were examined by their general practitioners, and a telephone interview was conducted with their caregivers. Four years later, the outcomes ‘institutionalization’ and ‘death’ were determined from health insurance data. Forty-one variables were examined for their predictive influence by univariate and multivariate Cox regression.

Results

The risk of institutionalization increased significantly (p ≤ 0.05) with older ages of patients [hazard ratio (HR) = 1.05] and caregivers (HR = 1.03), a higher educational level of the caregiver (HR = 1.83), greater use of community health services (HR = 1.59), greater caregiver burden (HR = 1.02), and when the caregiver and patient lived apart (HR = 1.97).

Conclusion

The results show that there is a multifactorial influence on institutionalization of dementia patients by sociodemographic, health-related, and psychological aspects as well as the care situation, thus validating the predictor model by Luppa et al. [Dement Geriatr Cogn Disord 2008;26:65-78]. Caregiver burden was found to be the strongest predictor accessible to interventions.

ACTIVE cognitive training and rates of incident dementia

Systematic cognitive training produces long-term improvement in cognitive function and less difficulty in performing activities of daily living. We examined whether cognitive training was associated with reduced rate of incident dementia. Participants were from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study (n = 2,802). Incident dementia was defined using a combination of interview- and performance-based methods. Survival analysis was used to determine if ACTIVE treatment affected the rate of incident dementia during 5 years of follow-up. A total of 189 participants met criteria for incident dementia. Baseline factors predictive of incident dementia were older age, male gender, African American race, fewer years of education, relationship other than married, no alcohol use, worse MMSE, worse SF-36 physical functioning, higher depressive symptomatology, diabetes, and stroke (all p < .05). A multivariable model with significant predictors of incident dementia and training group revealed that cognitive training was not associated with a lower rate of incident dementia. Cognitive training did not affect rates of incident dementia after 5 years of follow-up. Longer follow-up or enhanced training may be needed to fully explore the preventive capacity of cognitive training in forestalling onset of dementia.

Moderate alcohol consumption and cognitive risk

We reviewed 143 papers that described the relationship between moderate drinking of alcohol and some aspect of cognition. Two types of papers were found: (1) those that provided ratios of risk between drinkers and nondrinkers (74 papers in total) and (2) those that, although they did not provide such ratios, allowed cognition in drinkers to be rated as "better," "no different," or "worse" than cognition in nondrinkers (69 papers in total). The history of research on moderate drinking and cognition can be divided into two eras: 1977-1997 and 1998-present. Phase I (1977-1997) was the era of neuropsychological evaluation involving mostly young to middle-aged (18-50 years old) subjects. Although initial studies indicated moderate drinking impaired cognition, many later studies failed to confirm this, instead finding no difference in cognition between drinkers and nondrinkers. Phase II (1998-present) was and is the era of mental status exam evaluation involving mostly older (≥55 years old) subjects. These studies overwhelmingly found that moderate drinking either reduced or had no effect on the risk of dementia or cognitive impairment. When all the ratios of risk from all the studies in phase II providing such ratios are entered into a comprehensive meta-analysis, the average ratio of risk for cognitive risk (dementia or cognitive impairment/decline) associated with moderate "social" (not alcoholic) drinking of alcohol is 0.77, with nondrinkers as the reference group. The benefit of moderate drinking applied to all forms of dementia (dementia unspecified, Alzheimer's disease, and vascular dementia) and to cognitive impairment (low test scores), but no significant benefit against cognitive decline (rate of decline in test scores) was found. Both light and moderate drinking provided a similar benefit, but heavy drinking was associated with nonsignificantly higher cognitive risk for dementia and cognitive impairment. Although the meta-analysis also indicated that wine was better than beer or spirits, this was based on a relatively small number of studies because most studies did not distinguish among these different types of alcohol. Furthermore, a number of the studies that did make the distinction reported no difference among the effects of these different types of alcohol. Therefore, at present this question remains unanswered. Analysis also showed that the presence of the apolipoprotein E epsilon 4 allele eliminated the benefit of moderate drinking. However, this was based on a relatively small number of studies and several other studies have found a beneficial effect of the epsilon e4 allele. Further studies are necessary to settle this question. The benefit of moderate alcohol for cognition was seen in both men and women, although the amount and pattern of drinking is very different between the two sexes. Lastly, the finding of unaffected or significantly reduced cognitive risk in light to moderate drinkers was seen in 14/19 countries for which country-specific ratio data were available, with three of the five remaining countries showing nonsignificant reductions as well. Overall, light to moderate drinking does not appear to impair cognition in younger subjects and actually seems to reduce the risk of dementia and cognitive decline in older subjects.

Is physical activity a potential preventive factor for vascular dementia? A systematic review

BACKGROUND

Physical exercise has several beneficial effects, including reduced risk for Alzheimer's disease. Although several studies of potential risk factors for vascular dementia (VaD) exist, including physical activity, the studies have usually included few participants and there are no meta-analyses addressing this key topic.

METHODS

The MEDLINE database was searched using the key words 'physical exercise' 'activity' or 'walking' in combination with 'dementia' and 'vascular dementia'. Potentially relevant studies were assessed and summarised by two of the authors, and longitudinal studies with operationalized definition of physical activity providing risk for VaD in both groups were included in the meta-analysis using pooled estimates from a random effects model.

RESULTS

A total of 24 longitudinal studies, including 1378 patients with VaD, were included in the review. The majority of individual studies did not report significant associations. Five studies fulfilled criteria for meta-analysis, including 10,108 non-demented control subjects and 374 individuals with VaD. The meta-analysis demonstrated a significant association between physical exercise and a reduced risk of developing VaD: OR 0.62 (95% CI 0.42-0.92).

CONCLUSIONS

We conclude that there is evidence supporting the hypothesis that physical activity is likely to prevent the development of VaD, and should be highlighted as part of secondary prevention programmes in people at risk for cerebrovascular disease.

Home care patients in four Nordic capitals - predictors of nursing home admission during one-year followup

The aim was to predict nursing home admission (NHA) for home care patients after a 12-month follow-up study. This Nordic study is derived from the aged in home care (AdHOC) project conducted in 2001–2003 with patients at 11 sites in Europe. The participants in the cohort study were randomly selected individuals, aged 65 years or older, receiving homecare in Oslo, Stockholm, Copenhagen, and Reykjavik. The Resident Assessment Instrument for Home Care (version 2.0) was used. Epidemiological and medical characteristics of patients and service utilization were recorded for 1508 home care patients (participation rate 74%). In this sample 75% were female. The mean age was 82.1 (6.9) years for men and 84.0 (6.6) for women. The most consistent predictor of NHA was receiving skilled nursing procedures at baseline (help with medication and injections, administration or help with oxygen, intravenous, catheter and stoma care, wounds and skin care) (adjusted odds ratio = 3.7, 95% confidence interval: 1.7–7.8; P < 0.001). In this Nordic material, stronger emphasizing on higher qualified nurses in a home care setting could prevent or delay NHA.

Prediction of institutionalization in the elderly. A systematic review

OBJECTIVE

in the past decades, many studies have examined predictors of nursing home placement (NHP) in the elderly. This study provides a systematic review of predictors of NHP in the general population of developed countries.

DESIGN

relevant articles were identified by searching the databases MEDLINE, Web of Science, Cochrane Library and PSYNDEXplus. Studies based on population-based samples with prospective study design and identification of predictors by multivariate analyses were included. Quality of studies and evidence of predictors were determined.

RESULTS

thirty-six studies were identified; one-third of the studies were of high quality. Predictors with strong evidence were increased age, low self-rated health status, functional and cognitive impairment, dementia, prior NHP and a high number of prescriptions. Predictors with inconsistent results were male gender, low education status, low income, stroke, hypertension, incontinence, depression and prior hospital use.

CONCLUSIONS

findings suggested that predictors of NHP are mainly based on underlying cognitive and/or functional impairment, and associated lack of support and assistance in daily living. However, the methodical quality of studies needs improvement. More theoretical embedding of risk models of NHP would help to establish more clarity in complex relationships in using nursing homes.

The reasons for nursing home entry in an adult day care population: caregiver reports versus regression results

This article aims to compare reasons for nursing home entry determined through a regression of baseline predictors to relatives' perceptions of reasons for entry. Participants included 201 community-residing members of 5 senior day care centers in Maryland. Through a prospective design, statistical predictors using Cox regressions were compared to the relatives' reports of reasons for nursing home entry. These reports identified the most common reasons for nursing home entry as deterioration of independence and confusion. Behavior problems were also reported for almost half of the participants. In contrast, strong baseline statistical predictors of institutionalization were depressed affect, number of psychiatric diagnoses, a diagnosis of dementia, and age. Because of its strong significance within the baseline predictors, the meaning of depressed affect and why it was such a potent predictor of nursing home entry, yet still not reported by caregivers, should be studied further.