Depressive symptoms in later life: differential impact of social support and motivational processes on depression in individuals with and without cognitive impairment

Control Beliefs among People with Dementia: A Systematic Review

INTRODUCTION

Dementia diseases are still incurable, and in order to assist in living well with the disease, researchers are increasing their attention to the value of control beliefs. Control beliefs are associated with coping and psychological well-being; however, knowledge on how they relate to well-being outcomes in people with dementia is limited. This review aimed to synthesize knowledge about control beliefs in this group to guide future interventions and research.

METHOD

A systematic search of 6 databases (MEDLINE, CINAHL, PsychINFO, AgeLine, Embase, and the Cochrane Library) with broad search terms related to dementia, control, and coping was conducted. Studies that investigated people with a confirmed dementia diagnosis and that used a questionnaire to measure control beliefs quantitatively were included.

RESULTS

Eighteen studies were identified, examining self-efficacy, personal control/mastery, or locus of control. The studies varied in aim and design, with fair to good methodological quality. However, 10 studies included <50 participants with dementia, leaving findings unreliable due to low power. Participants with dementia in the mild to moderate stages were included, with average age in the seventies. Except for one validation study, the control belief questionnaires had not been validated for people with dementia.

CONCLUSION

There is a lack of knowledge about control beliefs among people with dementia, due to few and low-powered studies. Although we cannot conclude regarding control beliefs, our findings support the feasibility of quantitative research on control beliefs among people with dementia and we recommend that they be included in this type of research.

Locus of Control and Its Associations with Depressive Symptoms amongst People with Dementia

INTRODUCTION

Depression is common amongst people with dementia. This study examines whether locus of control (LoC), a perceived control construct influential in the coping process, is related to depressive symptoms in this population.

METHODS

In this prospective observational study, 257 community-dwelling older adults with a confirmed dementia diagnosis were included. At baseline, measures of depressive symptoms, LoC, cognition, independent functional ability, general health, dementia severity, and dementia disease insight were collected. At follow-up, measures of depressive symptoms and cognition were collected. Multiple linear regression using degree of depressive symptoms as measured with Montgomery-Asberg Depression Rating Scale as a dependent variable was applied to assess whether LoC was associated with depressive symptoms at baseline and follow-up while controlling for covariates.

RESULTS

LoC (p < 0.001), general health (p = 0.003), and insight (p = 0.010) were associated with severity of depressive symptoms at baseline, accounting for 28% of the variance. LoC (p = 0.025) and depressive symptoms (p < 0.001) at baseline were associated with severity of depressive symptoms at follow-up, accounting for 56.3% of the variance.

CONCLUSION

LoC was significantly associated with severity of depressive symptoms in people with dementia at baseline and at follow-up. Attention to LoC may be valuable for our understanding of depression in people with dementia, and interventions targeting depression could benefit from including a focus on internalizing perceived control. However, these findings are novel, and more research is needed.

The development of positive psychology outcome measures and their uses in dementia research: A systematic review

Positive psychology is gaining credence within dementia research but currently there is a lack of outcome measures within this area developed specifically for people with dementia. Authors have begun adopting positive psychology measures developed with other populations but there is no consensus around which are more appropriate or psychometrically robust. A systematic search identified measures used between 1998 and 2017 and an appraisal of the development procedure was undertaken using standardised criteria enabling the awarding of scores based on reporting of psychometric information. Twelve measures within the constructs of identity, hope, religiosity/spirituality, life valuation, self-efficacy, community and wellbeing were identified as being used within 17 dementia studies. Development procedures were variable and scores on development criterion reflected this variability. Of the measures included, the Herth Hope Index, Systems of Belief Inventory and Psychological Wellbeing Scale appeared to be the most robustly developed and appropriate for people with dementia.

Evidence for Different Trajectories of Delay Discounting in Older Adults With Mild Cognitive Impairment and Mild Alzheimer's Disease

Objectives

To examine whether delay discounting (DD) develops differently within individuals diagnosed with mild cognitive impairment (MCI) or mild Alzheimer's disease (AD).

Method

We set out to study trajectories of DD in N = 111 older adults (Mage = 75.2 years, range: 55-94, 53% female) with MCI (n = 64) or mild AD (n = 47). Data were repeatedly assessed on three measurement times over a period of 2 years.

Results

Results indicated a meaningful difference in the trajectories of DD between MCI and mild AD (t = 2.99, p = .004), with AD patients displaying higher DD rates compared with MCI. Lower intelligence (t = -2.50, p = .013) was related to higher DD. We also found reward-dependent group differences in DD (small: p = .079; medium: p = .258; large: p = .007). Age, functional ability, general cognitive ability, living situation, and marital status were not meaningfully linked to DD (all non significant). Further explorative analyses revealed an increase in DD in patients whose cognitive symptoms had progressed at time 2, compared with more stable courses of mild AD or MCI (diagnosed at time 2).

Discussion

Our results point toward an increase in DD as a function of advanced cognitive decline.

Caregiver perception of apathy in persons with mild cognitive impairment or Alzheimer's disease: a longitudinal study

OBJECTIVE

Discrepancy between self- and caregiver apathy ratings was examined longitudinally for persons with mild cognitive impairment or Alzheimer's disease. Particular focus was on the distinction between the positive and negative caregiver bias and its predictive value for a clinical diagnosis of apathy.

METHOD

Apathy rating discrepancy was based on the apathy evaluation scale. Dyads were categorized depending on whether the caregiver reported fewer deficits (positive caregiver bias) or more deficits (negative caregiver bias) than the cognitively impaired person did.

RESULTS

Caregiver ratings and rating discrepancy showed a significant increase from baseline to follow-up. By contrast, self- and clinician ratings showed no change across the two time points. Ratings with a negative caregiver bias remained stable, while those with a positive caregiver bias showed a significant increase in the caregiver ratings but also a significant decrease in the self-ratings. A negative caregiver bias at baseline was significantly related to greater likelihood of having clinical apathy at follow-up, adjusted for an array of control variables.

CONCLUSION

Positive and negative caregiver bias should be distinguished, as they seem to reflect distinct dyadic processes and are relevant for clinical outcome. Furthermore, negative rating discrepancies can be considered a risk factor for developing apathy.