Some approximation problems in the theory of stationary processes

AbstractIn this paper, necessary and sufficient conditions for the regularity of a general (multivariate) stationary process are obtained. These subsume all the known criteria of regularity for such processes

Promotion of healthy aging within a community center through behavior change: health and fitness findings from the AgeWell pilot randomized controlled trial

The purpose of this randomized controlled trial was to determine if behavior change through individual goal setting (GS) could promote healthy aging, including health and fitness benefits in older adults who attended a community “AgeWell” Center for 12 months. Seventy-five older adults were randomly allocated to either a control or a GS group. Health outcomes were measured at baseline and after 12 months of the participants’ having access to the exception of Agewell Center facilities. The findings demonstrate that participation in the Center in itself was beneficial, with improved body composition and reduced cardiovascular risk in both groups (p < .05), and that this kind of community-based resource offers valuable potential for promoting protective behaviors and reducing health risk. However, a specific focus on identifying individual behavior change goals was required in order to achieve increased activity engagement (p < .05) and to bring about more substantial improvements in a range of health, diet, and physical function measures (p < .05)

Cost-effectiveness findings from the Agewell pilot study of behaviour change to promote health and wellbeing in later life

Background: Participation in cognitive and physical activities may help to maintain health and wellbeing in older people. The Agewell study explored the feasibility of increasing cognitive and physical activity in older people through a goal-setting approach. This paper describes the findings of the cost-effectiveness analysis.Method: Individuals over the age of 50 and attending an Agewell centre in North Wales were randomised to one of three conditions: control (IC), goal-setting (GS), or goal-setting with mentoring (GM). We undertook a cost-effectiveness analysis comparing GS vs. IC, GM vs. IC and GM vs. GS. The primary outcome measure for this analysis was the QALY, calculated using the EQ-5D. Participants’ health and social care contacts were recorded and costed using national unit costs.Results: Seventy participants were followed-up at 12 months. Intervention set up and delivery costs were £252 per participant in the GS arm and £269 per participant in the GM arm. Mean health and social care costs over 12 months were £1,240 (s.d. £3,496) per participant in the IC arm, £1,259 (s.d. £3,826) per participant in the GS arm and £1,164 (s.d. £2,312) per participant in the GM arm. At a willingness to pay threshold of £20,000 per QALY there was a 65% probability that GS was cost-effective compared to IC (ICER of £1,070). However, there was only a 41% probability that GM was cost-effective compared to IC (ICER of £2,830) at a threshold of £20,000 per QALY.Conclusion: Setting up and running the community based intervention was feasible. Due to the small sample size it is not possible to draw a firm conclusion about cost-effectiveness; however, our preliminary results suggest that goalsetting is likely to be cost-effective compared to the control condition of no goal-setting, the addition of mentoring was effective but not cost-effective

Self-esteem, self-efficacy and optimism as psychological resources among family caregivers of people with dementia: findings from the IDEAL study

YesBeing a family caregiver, and in particular giving care to someone with dementia, impacts upon mental and physical health, and potentially reduces the ability of caregivers to ‘live well’. This paper examines whether three key psychological resources, self-efficacy, optimism and self-esteem, are associated with better outcomes for caregivers of people with dementia. Design and Participants Caregivers of 1283 people with mild-to-moderate dementia in the Improving the experience of Dementia and Enhancing Active Life (IDEAL) project responded to measures of selfefficacy, optimism and self-esteem, and ‘living well’ (quality of life, life satisfaction and well-being). Multivariate linear regression was used to examine the association between psychological resources and ‘living well’. Results Self-efficacy, optimism and self-esteem were all independently associated with better capability to ‘live well’ for caregivers. This association persisted when accounting for a number of potential confounding variables (age group, sex, and hours of caregiving per day). Conclusions Low self-efficacy, optimism and self-esteem might present a risk of poor outcomes for caregivers of people with dementia. These findings encourage us to consider how new or established interventions might increase the psychological resilience of caregivers

Exploring longitudinal changes in implicit awareness of dementia: An investigation of the emotional Stroop effect in healthy ageing and mild dementia

The aim of the study was to investigate responses to dementia‐relevant words in healthy older people and to investigate changes in response over 20‐months in people with early‐stage dementia. An emotional Stroop task, using colour‐naming dementia‐relevant words, was used as an indicator of implicit awareness of dementia. Overall, 24 people with dementia and 24 healthy older people completed an emotional Stroop task (T1). People with dementia completed the same task again after 12 (T2) and 20 (T3) months. For people with dementia emotional Stroop performance was contrasted with ratings of explicit awareness based on a detailed interview at T1 and at T2. For healthy older people and people with dementia response times to dementia‐relevant words were significantly longer than those for neutral words. The effect was absent for people with dementia at T3. This decline in the emotional Stroop effect was not associated with cognitive decline as measured by the MMSE. Ratings of explicit awareness showed no significant change over time. There was no association between explicit awareness and implicit awareness. Implicit awareness of the condition is evident in early‐stage dementia and can be elicited even where there is reduced explicit awareness. The emotional Stroop effect for dementia‐relevant words in people with dementia appears to decline over time, independently of changes in MMSE score, suggesting that implicit awareness fades as time progresses

Caregivers' beliefs about dementia: findings from the IDEAL study

YesObjective: Informal caregivers of people with dementia develop their own beliefs about the condition, referred to as Dementia Representations (DRs), as they try to make sense of the changes they are observing. The first aim of this study was to provide a profile of the types of DRs held by caregivers. The second aim was to examine the impact of caregivers’ DRs on their well-being, satisfaction with life (SwL) and caregiving stress. Methods: Participants were 1264 informal caregivers of people in the mild-to-moderate stages of dementia from time-point 1 of the IDEAL cohort study. Measures: DRs were measured using questionnaire items covering: Identity, Cause, Control, and Timeline. Results: Almost half (49.2%) of caregivers used a diagnostic term to describe the person’s condition, although 93.4% of caregivers stated they were aware of the diagnosis. Higher well-being, SwL, and lower caregiving stress were associated with the use of an identity term relating to specific symptoms of dementia, attributing the cause to ageing or not knowing the cause, and believing the condition would stay the same. Lower well-being, SwL, and higher caregiving stress were associated with believing there was little that could be done to control the effects of the condition. Conclusion: Healthcare professionals should assess and gain an understanding of caregivers’ DRs in order to provide more tailored information and support.The IDEAL study is funded by the Economic and Social Research Council (UK) and the National Institute for Health Research (UK) through grant ES/L001853/2 ‘Improving the experience of dementia and enhancing active life: living well with dementia’

Longitudinal trajectories of quality of life among people with mild-to-moderate dementia: a latent growth model approach with IDEAL cohort study data

Objectives We aimed to examine change over time in self-rated quality of life (QoL) in people with mild-to-moderate dementia and identify sub-groups with distinct QoL trajectories. Method We used data from people with mild-to-moderate dementia followed up at 12 and 24 months in the IDEAL cohort study (baseline n=1537). A latent growth model approach examined mean change over time in QoL, assessed with the QoL-AD scale, and investigated associations of baseline demographic, cognitive and psychological covariates with the intercept and slope of QoL. We employed growth mixture modelling to identify multiple growth trajectories. Results Overall mean QoL scores were stable and no associations with change over time were observed. Four classes of QoL trajectories were identified: two with higher baseline QoL scores, labelled Stable (74.9%) and Declining (7.6%), and two with lower baseline QoL scores, labelled Stable Lower (13.7%) and Improving (3.8%). The Declining class had higher baseline levels of depression and loneliness, and lower levels of self-esteem and optimism, than the Stable class. The Stable Lower class was characterised by disadvantage related to social structure, poor physical health, functional disability, and low psychological well-being. The Improving class was similar to the Stable Lower class but had lower cognitive test scores. Discussion Understanding individual trajectories can contribute to personalised care planning. Efforts to prevent decline in perceived QoL should primarily target psychological well-being. Efforts to improve QoL for those with poorer QoL should additionally address functional impairment, isolation, and disadvantage related to social structure

A comprehensive model of factors associated with subjective perceptions of living well with dementia: findings from the IDEAL study

Background: The concept of ‘living well’ is increasingly used to indicate that it is, or should be, possible for a person living with dementia to experience a subjective sense of ‘comfort, function and contentment with life.’ We used a theoretically-derived conceptual framework to investigate capability to ‘live well’ with dementia through identifying the relative contribution of domains associated with the subjective experience of living well. Methods: We analysed data from 1550 community-dwelling individuals with mild to moderate dementia participating in the baseline wave of the Improving the experience of Dementia and Enhancing Active Life (IDEAL) cohort study. Subjective perceptions of ability to live well were obtained by generating a living well latent factor from responses on the Quality of Life in Alzheimer’s disease (QoL-AD), Satisfaction with Life and WHO-5 Well-being scales. Multivariate modelling and structural equation modelling was used to investigate variables potentially associated with living well. Variables were grouped into five domains, latent variables were constructed representing Social Location, Capitals, Assets and Resources, Psychological Characteristics and Psychological Health, Physical Fitness and Health, and Managing Everyday Life with Dementia, and associations with living well were examined. All models were adjusted for age, sex and dementia sub-type. Results: Considering the domains singly, the Psychological Characteristics and Psychological Health domain was most strongly associated with living well (3.56; 95% CI: 2.25, 4.88), followed by Physical Fitness and Physical Health (1.10, 95% CI: -2.26, 4.47). Effect sizes were smaller for Capitals, Assets and Resources (0.53; 95% CI: -0.66, 1.73), Managing Everyday Life with Dementia (0.34; 95% CI: 0.20, 0.87), and Social Location (-0.12; 95% CI: -5.72, 5.47). Following adjustment for the Psychological Characteristics and Psychological Health domain, other domains did not show independent associations with living well. Conclusions: Psychological resources are central to subjective perceptions of living well and offer important targets for immediate intervention. Availability of social and environmental resources, and physical fitness, underpin these positive psychological states, and also offer potential targets for interventions and initiatives aimed at improving the experience of living with dementia

A comprehensive model of factors associated with subjective perceptions of living well with dementia: findings from the IDEAL study

Background: The concept of ‘living well’ is increasingly used to indicate that it is, or should be, possible for a person living with dementia to experience a subjective sense of ‘comfort, function and contentment with life.’ We used a theoretically-derived conceptual framework to investigate capability to ‘live well’ with dementia through identifying the relative contribution of domains associated with the subjective experience of living well. Methods: We analysed data from 1550 community-dwelling individuals with mild to moderate dementia participating in the baseline wave of the Improving the experience of Dementia and Enhancing Active Life (IDEAL) cohort study. Subjective perceptions of ability to live well were obtained by generating a living well latent factor from responses on the Quality of Life in Alzheimer’s disease (QoL-AD), Satisfaction with Life and WHO-5 Well-being scales. Multivariate modelling and structural equation modelling was used to investigate variables potentially associated with living well. Variables were grouped into five domains, latent variables were constructed representing Social Location, Capitals, Assets and Resources, Psychological Characteristics and Psychological Health, Physical Fitness and Health, and Managing Everyday Life with Dementia, and associations with living well were examined. All models were adjusted for age, sex and dementia sub-type. Results: Considering the domains singly, the Psychological Characteristics and Psychological Health domain was most strongly associated with living well (3.56; 95% CI: 2.25, 4.88), followed by Physical Fitness and Physical Health (1.10, 95% CI: -2.26, 4.47). Effect sizes were smaller for Capitals, Assets and Resources (0.53; 95% CI: -0.66, 1.73), Managing Everyday Life with Dementia (0.34; 95% CI: 0.20, 0.87), and Social Location (-0.12; 95% CI: -5.72, 5.47). Following adjustment for the Psychological Characteristics and Psychological Health domain, other domains did not show independent associations with living well. Conclusions: Psychological resources are central to subjective perceptions of living well and offer important targets for immediate intervention. Availability of social and environmental resources, and physical fitness, underpin these positive psychological states, and also offer potential targets for interventions and initiatives aimed at improving the experience of living with dementia

The impact of relationship quality on life satisfaction and well-being in dementia caregiving dyads: findings from the IDEAL study

Objectives: The quality of the relationship between people with dementia and their informal caregiver maybe an important determinant of life satisfaction and well-being for both members of the dyad. Taking a dyadic perspective, the aim of this study was to examine whether self- and partner-rated relationship quality influences life satisfaction and well-being for both people with dementia and their caregivers. Design and methods: Using data from 1283 dyads in the Improving the Experience of Dementia and Enhancing Active Life (IDEAL) cohort, we examined the impact of current relationship quality on life satisfaction and well-being in dementia caregiving dyads. Data were analysed using the Actor–Partner Interdependence Model (APIM) framework. Results: Self-rated relationship quality was associated with own life satisfaction and well-being for both people with dementia and caregivers. Partner-rated relationship quality did not influence own life satisfaction or well-being for either member of the dyad. Conclusion: This study is the first to use the APIM framework to explore the dyadic associations between relationship quality and life satisfaction and well-being in a large cohort of dementia caregiving dyads. The obtained findings suggest that the individual perception of the quality of the caregiving relationship held by each member of the caregiving dyad is an important factor for that member’s life satisfaction and well-being, while the partner’s perception of relationship quality is not. The findings highlight the importance of considering the individual perspective of both the person with dementia and the caregiver and enabling each to maintain positive perceptions of relationship quality