Spousal interrelations in self-reports of cognition in the context of marital problems

Occurrence and Risk Factors for Cognitive Decline Shared by Couples: A Systematic Review and Meta-Analysis

Background

To date, the magnitude of association and the quality of evidence for cognitive decline (mild cognitive impairment, Alzheimer's disease, and dementia) in couples and risk factors for outcomes have not been reviewed and analyzed systematically.

Objective

The aim of this study was to investigate the concordance of cognitive impairment in unrelated spouses and to qualitatively describe potential risk factors.

Methods

Eight databases were searched from inception to October 20, 2023. Eligible studies were independently screened and assessed for quality. Statistical analysis was conducted using Stata 15.1 software. The study was preregistered with PROSPERO (CRD42023488024).

Results

Eleven studies involving couples were included, with moderate to high evidence quality. Compared to controls, spouses of individuals with cognitive impairment had lower cognitive scores (Cohen's d: 0.18-0.62) and higher risk of cognitive decline (OR = 1.42, 95% CI: 1.15-1.76). The consistency of cognitive impairment between spouses was attributed to three theories: 1) the impact of caregiving stress experienced by the spouse; 2) assortative mating, which suggests that individuals select partners with similar characteristics; and 3) the influence of shared living environments and lifestyles.

Conclusions

The cognitive status of one spouse can affect the cognitive function of the other spouse. It is important to consider shared lifestyle, environmental, and psychobehavioral factors, as they may contribute to the risk of cognitive decline by couples. Identifying these factors can inform the development of targeted recommendations for interventions and preventive measures.

Spousal Synchrony in Allostatic Load Among Older Couples in the Health and Retirement Study

OBJECTIVE

Using national data from the Health and Retirement Study, this study examined interpartner associations of allostatic load (AL) among 2338 different-sex couples ( N = 4676 individuals) over a 4-year period among older American couples from a dyadic approach.

METHODS

AL was indexed by immune (C-reactive protein), metabolic (high-density lipoprotein cholesterol, total cholesterol, and glycosylated hemoglobin), renal (cystatin C), cardiovascular (systolic and diastolic blood pressures, pulse rate), and anthropometric (waist and body mass index) parameters using the traditional count-based formulation. Actor-partner interdependence models were used to assess interpartner concordance in AL.

RESULTS

Higher partners' baseline AL was significantly associated with higher own AL both at baseline and 4 years later. In addition, partners' baseline AL was significantly associated with own AL 4 years later only in women but not men. Lastly, we did not observe any significant moderating effect of relationship quality on interpartner AL concordance.

CONCLUSIONS

The findings suggest that older couples' physiological responses to environmental stress are not only linked concurrently, but the associations persist after 4 years, alluding to long-term impacts of couples' psychosocial context and physiology on each other.

Cognition and Financial Decision-Making in Older Adult Spouses

INTRODUCTION

Age-related decline in executive functioning has been found to negatively impact one's capacity to make prudent financial decisions. The broader literature also speaks to the importance of considering interrelatedness in older spouses' functioning, as these individuals typically represent one's longest and closest relationship that involves an extended history of shared experiences. Accordingly, the aim of the present study was to provide the first examination of whether older adults' financial decision-making capacity is impacted not only by their own but also by their partner's, level of cognitive functioning.

METHOD

Sixty-three heterosexual spousal dyads comprising older adults aged 60-88 participated. The contribution of executive functioning and perceptions of partner's cognitive decline on financial decision-making behavior and financial competency was assessed through two actor-partner interdependence models.

RESULTS

As predicted, for both genders, one's own executive functioning was predictive of one's own financial decision-making capacity. However, of particular interest was the finding that for females (but not males) perceiving greater cognitive decline in their spouse predicted their own (greater) financial competency.

CONCLUSION

Examining whether partner interdependence extends to the realm of financial decision-making is not only a theoretically but also practically important question. These data provide initial insights that such a relationship does exist and highlight further important avenues for future research.

Exploration of Cognitive Outcomes and Risk Factors for Cognitive Decline Shared by Couples

Importance

Although couples could share many risk factors of cognitive disorders in their lifetime, whether shared risk factors mediate the shared risk of cognitive disorders has rarely been investigated.

Objective

To identify the risk factors of cognitive decline shared within couples and investigate their mediating roles in the shared risk of cognitive disorders and cognitive functions within couples.

Design, Setting, and Participants

A prospective cohort study was launched in November 1, 2010, and 784 participants were followed up every 2 years until December 31, 2020. This nationwide, multicenter, community-based study included older couples from the Korean Longitudinal Study on Cognitive Aging and Dementia (KLOSCAD) and a cohort of their spouses (KLOSCAD-S).

Exposures

The cognitive disorder of a spouse was defined as mild cognitive impairment or dementia.

Main Outcomes and Measures

The mediating roles of factors shared within couples on the association between one spouse's cognitive disorder and the other's risk of cognitive disorders was examined with structural equation modeling.

Results

Included were 784 KLOSCAD participants (307 women [39.2%] and 477 men [60.8%]; mean [SD] age, 74.8 [4.8] years) and their spouses (477 women [60.8%] and 307 men [39.2%]; mean [SD] age, 73.6 [6.2] years). The cognitive disorder of the KLOSCAD participants was associated with almost double the risk of cognitive disorder of their spouses in the KLOSCAD-S cohort (odds ratio, 1.74; 95% CI, 1.12-2.69; P = .01). History of head injury (β = 0.50; 95% CI, 0.09-0.90; P = .02) and age (β = 2.57; 95% CI, 1.37-3.76; P < .001) mediated the association between cognitive disorder in the KLOSCAD participants and their spouses' risk of cognitive disorder. Physical inactivity mediated the association through major depressive disorder (β = 0.33, 95% CI, 0.09-0.57, P = .006 for physical inactivity; β = 0.28, 95% CI, 0.13-0.44, P < .001 for major depressive disorder). These factors similarly mediated the association between spousal cognitive disorder and cognitive functions such as memory and executive function.

Conclusions and Relevance

These findings suggest that the risk factors shared within couples may mediate approximately three-quarters of the spousal risk of cognitive disorders. Identification of and intervention in the shared risk factors of dementia within couples may reduce the risk of cognitive disorders in the spouses of people with dementia.

Similarities in cognitive abilities in older couples: a study of mutual influences

Objective: Similarities between spouses in cognitive functions have been mainly explained by the assortative mating phenomenon and the convergence for age and education. The mutual influence between spouses is another explanation particularly relevant in the elderly population. Today, it remains difficult to determine whether cognitive similarities exclusively result from the convergence effect or from the mutual influence. Using a novel methodology, the present study aimed to assess the impact of the marital relationship on cognitive similarities among elderly couples.Methods: 1723 couples from the Three-City Cohort Study were classified in two groups of couples with homogeneous and heterogeneous age and education. We also constituted two groups of pseudo-couples by a random association of individuals, with homogeneous and heterogeneous age and education. Dyadic analyses were conducted in the four groups, regarding the similarities in lexicosemantic abilities, executive functions, memory and global cognitive functioning.Results: Similarities were found on lexicosemantic abilities both in mate-assorted couples and in couples heterogeneous in age and education but no similarity was found in pseudo-couples.Discussion: Beyond the convergence effect, the fact that the spouses co-construct their lifestyles may contribute to cognitive similarities in the lexicosemantic domain.

Dyadic interrelations in lifespan development and aging: how does 1 + 1 make a couple? - introduction

Lifespan development and aging do not take place in a vacuum. It is increasingly recognized that others, who may be very familiar such as marital partners, often play a key role in shaping the developmental trajectories of their spouses. Further, this shaping seems at least partially dependent on the prolonged interactions that result in a high level of familiarity that is conducive to affecting the feelings, actions and reactions of the other member of the dyad. The studies comprising this special series on dyadic relationships tackle a number of specific mechanisms by targeting 2 domains of functioning that are central to successful aging, namely aspects of cognitive functioning and subjective well-being. The 4 papers adopt a range of methodologies, from an experimental session to short- and longer-term longitudinal observational studies. The authors of these articles offer novel insights into the theoretical underpinnings of spousal interrelations as well as how to approach such issues analytically. The closing discussion article draws out some of the underlying themes and highlights the important promises, but also the distinct challenges, of research on couples and dyads. Key avenues for future research are outlined, especially adapting principles of an epidemiological approach to understanding cognitive aging, broadly defined. These promise to extend our understanding of dyadic interrelations in lifespan development and aging.

Evaluating everyday competence in older adult couples: epidemiological considerations

Among older adults, everyday competence is often expressed in the context of other participating individuals. Although this active human context may be occasionally comprised of mere acquaintances, long-term partners (such as couples) often act as a unit in engaging in everyday actions or reporting on familiar domains. This special section reflects an important movement in aging research to examine couples as an alternative but normatively common unit of analysis. My discussion focuses on 2 main issues. First, I sketch the rationale, logic, expectation and evidence that long-term couples might develop and display unique advantages in everyday competence. Second, I explore the possibilities that epidemiological principles - thus far applied primarily to individual-level aging, decline and disease - may provide concepts or models for research on long-term changes in couple-level adaptation.