Psychological resources and glucoregulation in Japanese adults: Findings from MIDJA

Associations of work-family conflict with changes in metabolic risk factors: a four-year longitudinal study

Cardiovascular disease (CVD) is becoming prevalent among younger people who have dual roles at both work and home. A possible contributor to CVD is conflict between work and home life. Thus, this study investigated the impact of work-to-family conflict (WFC) and family-to-work conflict (FWC) on metabolic risk factors. We used longitudinal data with a 4-yr interval from the Midlife in Japan study. 152 participants who were employed at baseline without missing variables of interest were included. We assessed the associations of baseline WFC and FWC with changes in metabolic risk factors between baseline and follow-up using Generalized Estimating Equations. After adjusting for baseline sociodemographic, work and family-related, and lifestyle factors, the fully adjusted model showed WFC was significantly associated with changes in low-density lipoprotein cholesterol (LDL-C) and Total cholesterol (TC)/high-density lipoprotein cholesterol (HDL-C) ratio. However, FWC was not significantly associated with changes in any metabolic risk factors. Our findings indicated a significant impact of WFC on LDL-C and TC/HDL-C ratio but no significant impact of FWC on metabolic health. Since these metabolic risk factors cause CVD, understanding the physiological responses to occupational psychosocial stress could help create primary prevention interventions and assess their effects on workers' metabolic health.

A review of the literature on wellbeing and modifiable dementia risk factors

Wellbeing-defined broadly as experiencing one's life as enjoyable and fulfilling-has been associated with lower risk for Alzheimer's disease and related dementias. The mechanisms underlying this association are largely unknown. However, prior research and theory suggest that wellbeing impacts health behaviors and biological systems that are relevant to cognitive and brain health. Several of these factors have also been identified by the 2020 Lancet Commission on Dementia Prevention, Intervention, and Care as modifiable dementia risk factors. In the current review, we summarize and evaluate the evidence for associations between wellbeing and each of the 12 Lancet Commission risk factors. We found relatively consistent evidence for associations between higher wellbeing and lower levels of most of the risk factors: physical inactivity, social isolation, smoking, depression, hypertension, diabetes, hearing loss, traumatic brain injury, and air pollution. By contrast, we found evidence for only modest associations between wellbeing and education and mixed evidence for associations of wellbeing with alcohol use and body weight. Although most of the reviewed evidence was observational, longitudinal and experimental evidence suggests that many of the observed associations are likely bidirectional. These findings suggest that modifiable dementia risk factors may be mediators (i.e., intermediate steps in the causal chain) and/or confounders (i.e., variables that impact both wellbeing and dementia, and thus could induce a spurious association) of the association between wellbeing and dementia. We conclude by discussing next steps to test mediation hypotheses and to account for potential confounding in the relation between wellbeing and dementia.

Associations for Sense of Purpose with Smoking and Health Outcomes Among Adults with Diabetes

BACKGROUND

Health complications from diabetes place major strain on individuals, financially and emotionally. The onset and severity of these complications are largely driven by patients' behaviors, making psychosocial factors that influence behaviors key targets for interventions. One promising factor is sense of purpose or the degree to which a person believes their life has direction.

METHOD

The current study investigated whether sense of purpose predicts self-rated health, cardiovascular disease, and smoking status among adults with diabetes concurrently and prospectively. Moreover, it tested whether these associations held across multiple samples and cultures. Coordinated analysis using 12 datasets cross-sectionally and eight longitudinally (total N = 7277) estimated the degree to which sense of purpose is associated with subjective health, smoking status, and cardiovascular disease among adults with diabetes. Coordinated analysis allows for greater generalizability of results across cultures, time periods, and measurement instruments. Datasets were included if they concurrently included a measure of sense of purpose and diabetes status and at least one health measure: self-rated health, current smoking status, or heart condition status.

RESULTS

Sense of purpose was associated with higher self-rated health, smoking status, and cardiovascular disease cross-sectionally and self-rated health prospectively. Purpose was unassociated with changes in health over time.

CONCLUSION

These results highlight the relationship of a key individual difference, sense of purpose, to the behaviors and outcomes of adults with diabetes. While more research is needed to determine the boundaries of this relationship, it seems sense of purpose may be considered in the future as a potential target for intervention.

Formulations of Job Strain and Psychological Distress: A Four-year Longitudinal Study in Japan

Background

Different job strain formulations based on the Job Demand-Control model have been developed. This study evaluated longitudinal associations between job strain and psychological distress and whether associations were influenced by six formulations of job strain, including quadrant (original and simplified), subtraction, quotient, logarithm quotient, and quartile based on quotient, in randomly selected Japanese workers.

Methods

Data were from waves I and II of the Survey of Midlife in Japan (MIDJA), with a 4-year follow-up period. The study sample consisted of 412 participants working at baseline and had complete data on variables of interest. Associations between job strain at baseline and psychological distress at follow-up were assessed via multivariable linear regression, and results were expressed as β coefficients and 95% confidence intervals including R2 and Akaike information criterion (AIC) evaluation.

Results

Crude models revealed that job strain formulations explained 6.93-10.30% of variance. The AIC ranged from 1475.87 to 1489.12. After accounting for sociodemographic and behavioral factors and psychological distress at baseline, fully-adjusted models indicated significant associations between all job strain formulations at baseline and psychological distress at follow-up: original quadrant (β: 1.16, 95% CI: 0.12, 2.21), simplified quadrant (β: 1.01, 95% CI: 0.18, 1.85), subtraction (β: 0.39, 95% CI: 0.09, 0.70), quotient (β: 0.37, 95% CI: 0.08, 0.67), logarithm quotient (β: 0.42, 95% CI: 0.12, 0.72), and quartile based on quotient (β: 1.22, 95% CI: 0.36, 2.08).

Conclusion

Six job strain formulations showed robust predictive power regarding psychological distress over 4 years among Japanese workers.

Contributions of Eudaimonic Well-Being to Mental Health Practice

Purpose

Synergies between a eudaimonic model of psychological well-being (Ryff, 1989) and mental health practice are examined. The model grew out of clinical, developmental, existential, and humanistic perspectives that emphasized psychological strengths and capacities, in contrast to the focus on emotional distress and dysfunction in clinical psychology.

Design/Approach

Conceptual foundations of the eudaimonic approach are described, along with the six components positive functioning that are used to measure well-being. These qualities may be important in facilitating the recovery experiences, which are of interest in Mental Health and Social Inclusion.

Findings

Four categories of empirical evidence about eudaimonia are reviewed: (1) how it changes with aging, (2) how it matters for health, (3) what are its biological and neurological underpinnings, and (4) whether it can be promoted. Major contemporary forces against eudaimonia are also considered, including ever-widening inequality, the enduring pandemic, and world-wide strife. In contrast, encounters with the arts and nature are put forth as forces for eudaimonia. The relevance of these ideas for mental health research and practice is considered.

Originality

Mental health is often defined as the absence of mental illness. The novelty of the eudaimonic approach is to define mental health as the presence of well-being, assessed with different components of positive functioning.

Practical Implications

Enormous suffering defines our contemporary world. Such realities call for greater attention to factors that undermine as well as nurture the realization of human potential, the core of eudaimonic well-being.

Healthy Eating as Potential Mediator of Inverse Association between Purpose in Life and Waist Circumference: Emerging Evidence from US and Chilean Cohorts

High sense of purpose in life, a fundamental domain of eudaimonic well-being, has been consistently associated with lower risk for various obesity-related chronic diseases. Although this psychological feature correlates with some health behaviors as potential mediators, its association with healthy eating remains less explored. In addition, studies of these psycho-behavioral and health relationships in the South American population are lacking. This research sought to assess: (1) the cross-sectional association between self-reported purpose in life and overall healthy eating patterns, and (2) healthy food intake as a potential mediator of the inverse relationship between purpose in life and waist circumference. Data collected of 2060 US adults from the MIDUS study (5 ± 12 years, 55% women, mostly white people, and 42.5% obese) and 223 Chilean adults from the CHILEMED study (46.6 ± 9 years, 58.3% women, and 71.3% obese) were used. Anthropometric and sociodemographic variables were collected. Sense of purpose was assessed using the purpose in life subscale of the Ryff's psychological well-being questionnaire. Diet quality was evaluated using healthy eating or low-fat diet indexes, according to extant food intake data in each cohort. The relationship between these variables was estimated by bivariate and multivariate linear regressions with appropriate adjustments. To establish whether a better diet quality could mediate a link of purpose in life and improved nutritional status (assessed by waist circumference), the association between these three variables was tested by bootstrapping-based mediation analysis. Our results show significant associations of sense of purpose with healthy eating and low-fat dietary patterns in both US and Chilean cohorts, respectively, even after adjusting for sociodemographic variables. According to the mediation analysis, the relationship between sense of purpose and waist circumference, as an indicator of abdominal obesity, appears to be partially mediated by healthier food intake in both samples. In conclusion, our findings suggest a plausible mechanism underlying the favorable impact of this well-being dimension on physical health. Given its protective effects, interventions aimed at increasing purpose in life may facilitate adherence to better dietary patterns, which, in turn, will reduce the risk for obesity-related chronic diseases.

Links of positive affect and stress to HbA1c: a prospective longitudinal study

While affect is linked to a number of diabetes outcomes, the specific role of positive affect (PA) in HbA1c remains unclear. The present study examined whether PA prospectively predicted lower HbA1c among adults with type 2 diabetes and whether this relation was moderated by stress. Participants were 123 adults (44.7% female; 60.2% White, 39.8% Black) recently diagnosed with type 2 diabetes. Perceived stress, diabetes-specific distress, and PA were assessed at baseline; HbA1c was assessed at baseline (T1), six months (T2), and five years (T3). PA was cross-sectionally associated with lower HbA1c at T1 and prospectively predicted lower HbA1c at T3. PA interacted with both measures of T1 stress to predict T1 HbA1c, and PA interacted with T3 perceived stress to predict T3 HbA1c. Interactions were consistent with stress buffering. Sensitivity analyses attentuated findings, but robust evidence remained for PA as a protective factor for blood glucose five years later and for a stress-buffering effect of PA on diabetes-specific distress. Findings suggest PA may be a clinically useful indicator among adults with type 2 diabetes and may be particularly important for those experiencing the greatest stress from their disease.

Purpose in life promotes resilience to age-related brain burden in middle-aged adults

BACKGROUND

Disease-modifying agents to counteract cognitive impairment in older age remain elusive. Hence, identifying modifiable factors promoting resilience, as the capacity of the brain to maintain cognition and function with aging and disease, is paramount. In Alzheimer's disease (AD), education and occupation are typical cognitive reserve proxies. However, the importance of psychological factors is being increasingly recognized, as their operating biological mechanisms are elucidated. Purpose in life (PiL), one of the pillars of psychological well-being, has previously been found to reduce the deleterious effects of AD-related pathological changes on cognition. However, whether PiL operates as a resilience factor in middle-aged individuals and what are the underlying neural mechanisms remain unknown.

METHODS

Data was obtained from 624 middle-aged adults (mean age 53.71 ± 6.9; 303 women) from the Barcelona Brain Health Initiative cohort. Individuals with lower (LP; N = 146) and higher (HP; N = 100) PiL rates, according to the division of this variable into quintiles, were compared in terms of cognitive status, a measure reflecting brain burden (white matter lesions; WMLs), and resting-state functional connectivity, examining system segregation (SyS) parameters using 14 common brain circuits.

RESULTS

Neuropsychological status and WMLs burden did not differ between the PiL groups. However, in the LP group, greater WMLs entailed a negative impact on executive functions. Subjects in the HP group showed lower SyS of the dorsal default-mode network (dDMN), indicating lesser segregation of this network from other brain circuits. Specifically, HP individuals had greater inter-network connectivity between specific dDMN nodes, including the frontal cortex, the hippocampal formation, the midcingulate region, and the rest of the brain. Greater functional connectivity in some of these nodes positively correlated with cognitive performance.

CONCLUSION

Expanding previous findings on AD pathology and advanced age, the present results suggest that higher rates of PiL may promote resilience against brain changes already observable in middle age. Furthermore, having a purposeful life implies larger functional integration of the dDMN, which may potentially reflect greater brain reserve associated to better cognitive function.

Optimism and Longevity Among Japanese Older Adults

BACKGROUND

Optimism has been linked to better physical health across various outcomes, including greater longevity. However, most evidence is from Western populations, leaving it unclear whether these relationships may generalize to other cultural backgrounds. Using secondary data analysis, we evaluated the associations of optimism among older Japanese adults.

METHODS

Data were from a nationwide cohort study of Japanese older adults aged ≥65 years (Japan Gerontological Evaluation Study; n = 10,472). In 2010, optimism and relevant covariates (i.e., sociodemographic factors, physical health conditions, depressive symptoms, and health behaviors) were self-reported. Optimism was measured using the Japanese version of the Life Orientation Test-Revised (LOT-R). Lifespan was determined using mortality information from the public long-term care insurance database through 2017 (7-year follow-up). Accelerated failure time models examined optimism (quintiles or standardized continuous scores) in relation to percent differences in lifespan. Potential effect modification by gender, income, and education was also investigated.

RESULTS

Overall, 733 individuals (7%) died during the follow-up period. Neither continuous nor categorical levels of optimism were associated with lifespan after progressive adjustment for covariates (e.g., in fully-adjusted models: percent differences in lifespan per 1-SD increase in continuous optimism scores= -1.2%, 95%CI: -3.4, 1.1 higher versus lower optimism quintiles= -4.1%, 95%CI: -11.2, 3.6). The association between optimism and lifespan was null across all sociodemographic strata as well.

CONCLUSION

Contrary to the existing evidence from Western populations, optimism was unrelated to longevity among Japanese older adults. The association between optimism, as evaluated by the LOT-R, and longevity may differ across cultural contexts.

Ikigai and subsequent health and wellbeing among Japanese older adults: Longitudinal outcome-wide analysis

BACKGROUND

Having a purpose in life has been linked to improved health and wellbeing; however, it remains unknown whether having "Ikigai"-a related but broader concept in Japan-is also beneficial for various physical and psychosocial outcomes.

METHODS

Using data from a nationwide longitudinal study of Japanese older adults aged ≥65 years, we examined the associations between having Ikigai in 2013 and a wide range of subsequent outcomes assessed in 2016 across two databases (n = 6,441 and n = 8,041), including dimensions of physical health, health behavior, psychological distress, social wellbeing, subjective wellbeing, and pro-social/altruistic behaviors. We adjusted for sociodemographic characteristics and the outcome values (whenever data were available) in the prior wave (2010).

FINDINGS

Having Ikigai (vs. not having Ikigai) was associated with a 31% lower risk of developing functional disability [95% confidence interval (CI) for risk ratio: 0.58, 0.82] and 36% lower risk of developing dementia [95% CI for risk ratio: 0.48, 0.86] during the three-year follow-up. Having Ikigai was associated with decreased depressive symptoms and hopelessness as well as higher happiness, life satisfaction, instrumental activity of daily living, and certain social outcomes (e.g., more frequent participation in hobby clubs). Some of these associations were stronger for men than women, and among individuals with high socioeconomic status (p-values for effect measure modification < 001).

INTERPRETATION

Having Ikigai may promote health and wellbeing outcomes among Japanese older adults, but particularly men and individuals with high socioeconomic status.

FUNDING

NIH, John Templeton Foundation, JSPS, AMED, MHLW, MEXT, and WPE Foundation.

Negative and Positive Psychosocial Factors in Relation to Cognitive Health in Older African Americans

Background and Objectives

Identifying potential intervention strategies to reduce cognitive decline, particularly among older African Americans at high risk for Alzheimer’s dementia, is critical. This study aimed to investigate whether depressive symptoms, purpose in life, and their interrelations are associated with cognitive decline in older African Americans.

Research Design and Methods

We included older African Americans from the Minority Aging Research Study (n = 748) and Rush Memory and Aging Project (n = 109), without dementia at baseline. We assessed associations of depressive symptoms, purpose in life, and their interrelations, with baseline levels and change in global cognition using linear mixed-effects models.

Results

At baseline, each unit increment in depressive symptoms was related to worse initial global cognition (mean difference = −0.03 standard unit; p = .003), while higher purpose in life was related to better cognition (mean difference = 0.12; p = .002). Further, participants with ≥1 depressive symptom who had a purpose in life score above the median appeared to have better global cognition (mean difference = 0.10; p = .01), compared to those with depressive symptoms but lower levels of purpose in life. However, we did not find relations of depressive symptoms or purpose in life with rates of cognitive decline over time, likely due to the modest follow-up.

Discussion and Implications

In older African Americans, we found that lower depressive symptoms and greater purpose in life were independently related to higher initial levels of global cognition, but not cognitive decline. Preliminary findings of higher global cognition in individuals with depressive symptoms but greater purpose in life merit further investigation if purpose may eventually be considered as an intervention.

Culture and Health: Recent Developments and Future Directions 1

Evidence of cultural differences in relationships and emotions has accumulated over the past few decades. As findings on cultural differences in psychological processes have accumulated, there has been growing interest in investigating whether they have implications for other phenomena such as health. Using scientific advances from the MIDUS and MIDJA studies, both publicly available, we examine links between culture and health. We first briefly review the accumulated evidence on cultural influences on health correlates of psychosocial factors. We then feature two recent developments - a more micro-level perspective on biological factors that may be involved in the culture and health linkage, and a more macro-level view of socioeconomic inequality, which also matters for health. Both perspectives inform the pathways through which health effects occur. Finally, we conclude our review by highlighting the changing historical contexts surrounding these cross-cultural investigations. Specifically, we draw attention to widening of economic inequality across cultures and the world-wide COVID-19 pandemic. These happenings bring notable implications for future research on health across cultural contexts.

Psychological Resources and Biomarkers of Health in the Context of Chronic Parenting Stress

Background

Epidemiological studies link psychological resources to better physical health. One reason may be that psychological resources are protective in stressful contexts. This study tested whether indeed psychological resources are protective against biological degradation for healthy mid-life women under the chronic stress of caring for a child with an autism spectrum disorder diagnosis (“caregivers”).

Methods

We tested whether five types of psychosocial resources (i.e., eudaimonic well-being, autonomy, purpose in life, self-acceptance, and mastery) were associated with biological indices of aging in a sample of mid-life women stratified by chronic stress; half were caregivers (n = 92) and half were mothers of neurotypical children (n = 91; controls). Selected stress and age related biological outcomes were insulin resistance (HOMA-IR), systemic inflammation (IL-6, CRP), and cellular aging (leukocyte telomere length). We tested whether each resource was associated with these biomarkers, and whether caregiving status and high parenting stress moderated that relationship.

Results

All the psychological resources except mastery were significantly negatively associated with insulin resistance, while none were related to systemic inflammation or telomere length. The relationships between eudaimonic well-being and HOMA-IR, and self-acceptance and HOMA-IR, were moderated by parental stress; lower resources were associated with higher insulin resistance, but only for women reporting high parental stress. The well-known predictors of age and BMI accounted for 46% of variance in insulin resistance, and psychological resources accounted for an additional 13% of variance. 

Conclusion

These findings suggest that higher eudaimonic well-being and greater self-acceptance may be protective for the metabolic health of mid-life women, and particularly in the context of high parenting stress. This has important implications given the rising rates of both parental stress and metabolic disease, and because psychological interventions can increase eudaimonic well-being and self-acceptance.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12529-021-10007-z.

Positive psychological well‐being and cardiovascular disease: Exploring mechanistic and developmental pathways

Empirical research regarding the health benefits of positive psychological well‐being (e.g., positive emotions, life satisfaction, purpose in life, and optimism) has flourished in recent years, particularly with regard to cardiovascular disease. This paper reviews the state of evidence for well‐being's association with cardiovascular disease in both healthy individuals and those diagnosed with a disease. Prospective studies consistently indicate well‐being reduces cardiovascular events in healthy and, to a lesser extent, patient populations. Potential pathways that link well‐being with cardiovascular disease are discussed (including health behaviors, physiological processes, and stress buffering), although the existing evidence is mostly cross‐sectional which limits conclusions about directionality. Issues related to development across the lifespan are considered and childhood is identified as a crucial period for establishing healthy cardiovascular trajectories. Outstanding questions for future research are provided with recommendations to focus on well‐powered and prospective study designs with rigorous assessment of both well‐being and cardiovascular‐related outcomes.

Resilient Aging: Psychological Well-Being and Social Well-Being as Targets for the Promotion of Healthy Aging

Population aging is one of the most important social trends of the 21st century and in the United States, the number of people aged ≥65 is projected to increase by nearly 50% in the next 15 years. Most biomedical and public health efforts have focused on reducing harmful risk factors when targeting chronic disease—an approach that has contributed greatly to prevention and treatment programs. However, evidence suggests that the number of years lost to disability is increasing and historic gains we have made in life expectancy are eroding, and even reversing in some groups. As our society ages and grapples with these issues, expanding the focus to include resilience, as well as psychosocial assets in our prevention and treatment programs might help inform the multidisciplinary response effort we need. Here we synthesize research evaluating associations between different dimensions of psychological well-being (e.g., purpose in life, optimism, life satisfaction) and social well-being (e.g., structural, functional, quality) with chronic conditions. We also evaluate evidence around three biopsychosocial pathways hypothesized to underlie these associations. These factors are meaningful, measurable, and potentially modifiable; thus, further pursuing this line of inquiry might unveil innovative paths to enhancing the health of our rapidly aging society.

Cross-Cultural Nomological Network of Gratitude: Findings From Midlife in the United States (MIDUS) and Japan (MIDJA)

Gratitude enhances prosocial behavior and is considered a positive trait in most cultures, yet relatively little is known about its relationship to other psychological constructs, nor how it varies across diverse cultural contexts. To investigate the cross-cultural consistency of the benefits of having a grateful disposition, the current study examined the nomological network of gratitude in the United States and Japan, using data from two longitudinal studies: Midlife in the United States (MIDUS Refresher Biomarker Project) and Midlife in Japan (MIDJA). Results showed significant positive bivariate associations between trait gratitude and positive psychological functioning (Satisfaction with Life, Sympathy, Anger Control, Cognition Control, and Support/Affectual Solidarity Given to Relational Network) in both the United States and Japan. On the other hand, trait gratitude was negatively correlated with constructs associated with maladaptive psychological processes (Perceived Stress, Social Anxiety, Loneliness, and Anger-In) in both countries. The present findings provide valuable guidance for the development and implementation of future interventions that may lead to positive outcomes in individuals from diverse cultural and ethnic backgrounds.

Poor glucose regulation is associated with declines in well-being among older men, but not women

Glucose regulation is a key aspect of healthy aging and has been linked to brain functioning and cognition. Here we examined the role of glucose regulation for within-person longitudinal trajectories of well-being. We applied growth models to data from the Berlin Aging Study II (N = 955), using insulin resistance as an index of glucoregulatory capacity. We found that poor glucose regulation (higher insulin resistance) was consistently associated with lower levels of well-being among older men but not women. Our study provides novel evidence for the relevance of glucose regulation for well-being among older men. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Culture moderates the link between perceived obligation and biological health risk: Evidence of culturally distinct pathways for positive health outcomes

RATIONALE

Although perceived obligations to meet the expectations of family, friends, and society can be detrimental to physical health, much research in this area has thus far been conducted exclusively on Western samples. Cross-cultural research importantly suggests that positive health can be dependent on whether one engages in modes of being that are sanctioned by one's culture. Specifically, studies show that better health is predicted when people from cultures that value independence are able to exercise their personal autonomy and when people from cultures that value interdependence are able to maintain relational harmony (Kitayama et al., 2010).

OBJECTIVE

Based on these lines of research, as the fulfillment of perceived obligations can facilitate relational harmony but infringe on personal autonomy, we posit that culture will moderate the impact of perceived obligations on health outcomes. To gain further insight, we additionally examined people's goal disengagement tendency as an individual difference that may influence their likelihood of shunning perceived obligations in order to avoid associated stressors.

METHOD

Drawing from the parallel biomarker projects of Midlife in the United States and Midlife in Japan, we examined the interaction between perceived obligations and goal disengagement tendency on health among American and Japanese middle-aged adults. Health outcomes were indexed by biomarkers of inflammation (interleukin-6 and C-reactive protein levels) and cardiovascular risk (systolic blood pressure and total/high-density lipoprotein cholesterol).

RESULTS

We found that a higher tendency to disengage from stressful social obligations is associated with better health for Americans. In contrast, we found poorer health outcomes amongst Japanese participants who tend to disengage from their perceived obligations.

CONCLUSIONS

Our results highlight the importance of examining how perceived obligations influence physical health from a cultural perspective. The current study supports the hypothesis that culturally distinct pathways underlie health outcomes.

Sense of Purpose in Life and Cardiovascular Disease: Underlying Mechanisms and Future Directions

PURPOSE OF REVIEW

In this review, we synthesize recent research that has reported associations of a higher sense of purpose in life with reduced risk of developing cardiovascular disease (CVD), and then explore mechanisms that might underlie these associations.

RECENT FINDINGS

Accumulating observational and experimental evidence suggests that having a higher sense of purpose might influence CVD risk through three pathways: (1) enhancement of other psychological and social resources that buffer against the cardiotoxic effects of overwhelming stress; (2) indirect effects through health behaviors; and (3) direct effects on biological pathways. A sense of purpose in life is emerging as an independent risk factor for incident CVD. A key remaining question is whether purpose causally effects CVD risk; in the "Future Research Directions" section, we focus on work needed to establish causality and provide suggestions for next steps.

Purpose in life and tobacco use among community-dwelling mothers of early adolescents

OBJECTIVES

The rising prevalence of tobacco use and tobacco-attributable deaths among women is of worldwide concern. In particular, smoking prevention for mothers in early midlife is a significant international public health goal. A higher sense of purpose in life (PIL) is thought to reduce detrimental health behaviours. However, little is known about the association between a sense of PIL and tobacco use. This study investigates this association among community-dwelling mothers of early adolescents.

DESIGN

This population-based cross-sectional study uses a self-reported questionnaire from the Tokyo Early Adolescence Survey, a large community-based survey conducted in Japan between 2012 and 2015.

SETTING

Participants were randomly recruited from the resident registries of three municipalities in Tokyo, Japan.

PARTICIPANTS

A total of 4478 children and their primary parents participated. Responses from 4063 mothers with no missing data were analysed (mean age=42.0 years (SD=4.2)).

MEASURES

Participants' tobacco use, including the number of cigarettes smoked per day, was documented using a questionnaire. PIL was assessed using a Purpose in Life scale derived from Ryff's Psychological Well-Being Scale.

RESULTS

Greater PIL was associated with a decreased likelihood of tobacco use, even when adjusted for confounders (OR=0.80, 95% CI 0.70 to 0.91). Multinomial logistic regression analyses revealed that PIL was inversely associated with tobacco consumption among mothers. These associations remained after controlling for psychological distress, socioeconomic factors and frequency of alcohol consumption among moderate to heavy smokers (OR=0.70, 95% CI 0.57 to 0.86), while attenuated among light smokers.

CONCLUSIONS

Increasing PIL may be a valuable intervention for reducing tobacco use among women in early midlife. This study can contribute to our understanding of the psychology of smoking behaviour and shed light on the targeted intervention to reduce tobacco use among early midlife mothers.

Psychometric properties and population norms of the positive mental health instrument in a representative multi-ethnic Asian population

Background

Measures of mental well-being and positive mental health (PMH) have been largely developed and used in Western populations, however, data on representative Asian communities are lacking. Using data from a population sample, this study sought to establish psychometric properties and norms of the PMH Instrument (PMH-I), a measure of positive mental health developed in Singapore.

Methods

We conducted a nationally representative survey among 1925 adults aged 18–79 years of Chinese, Malay, Indian or other ethnicity. Participants reported socio-demographic characteristics and completed the PMH-I along with measures of health-related quality of life (HRQoL) and psychological distress. Construct validity of the PMH-I was assessed using confirmatory factor analysis and concurrent validity was tested through correlation with other psychological measures. Normative PMH values and differences in population subgroups were estimated.

Results

The six-factor-higher-order structure of the PMH-I comprising six subscales of general coping, emotional support, spirituality, interpersonal skills, personal growth and autonomy and global affect was confirmed. Concurrent validity was shown through significant positive correlation of the total PMH score and its subscales with HRQoL and an inverse correlation with psychological distress. Weighted age, gender and ethnicity-specific norms were derived for the Singapore population. Total PMH was significantly higher in participants aged over 40 years as compared with 18–29 year olds and in non-Chinese ethnic groups as compared with Chinese. These differences were observed for all PMH-I subscales, with the exception of emotional support and interpersonal skills score differences by age. In contrast, gender, marital status, and education level were significantly associated with some of the subscales, but not with total PMH.

Conclusions

These results support the psychometric properties of the PMH-I in a multi-ethnic Asian population sample. The generalizable population-based norms support the application of the PMH-I for measuring mental health and assessing its determinants within the Singapore general population.

Electronic supplementary material

The online version of this article (10.1186/s12874-018-0487-9) contains supplementary material, which is available to authorized users.

Persistently high psychological well-being predicts better HDL cholesterol and triglyceride levels: findings from the midlife in the U.S. (MIDUS) longitudinal study

Background

Psychological correlates of blood lipid levels have been previously evaluated mostly in cross sectional studies. However, prospectively measured psychological factors might also predict favorable blood lipid profiles, thereby indicating a healthy mind/body interplay that is associated with less disease, better health and longer lives.

Methods

This paper examined whether longitudinal profiles of psychological well-being over 9–10 years are predictors of blood lipid profiles. Using the MIDUS (Midlife in the U.S.) biological subsample (n = 1054, aged 34 to 84, 55% female), cross-time trajectories of well-being were linked with three lipid outcomes (i.e., HDL cholesterol, triglycerides, and LDL cholesterol), measured for the first time at the 2nd wave of the study.

Results

Most adults showed largely stable profiles of well-being, albeit at different levels. Some showed persistently high well-being over time, while others revealed persistently low or moderate well-being. After adjusting for the effect of demographics, health behaviors, medications, and insulin resistance, adults with persistently high levels of environmental mastery and self-acceptance—two components of psychological well-being—had significantly higher levels of HDL as well as significantly lower levels of triglycerides compared to adults with persistently low levels of well-being. Converging with prior findings, no association was found between well-being and LDL cholesterol.

Conclusions

Over 9–10 years, persistently high levels of psychological well-being measures predicted high HDL cholesterol and low triglycerides. These findings add longitudinal evidence to the growing body of research showing that positive psychological factors are linked with better lipoprotein profiles. A better blood lipid profile, particularly higher HDL-C, may be key in mediating how psychological well-being positively impacts health and length of life. Additional research is required to further validate this hypothesis as well as to establish potential underlying mechanisms.

Association Between Purpose in Life and Objective Measures of Physical Function in Older Adults

IMPORTANCE

Higher purpose in life is hypothesized to reduce the likelihood of developing weak grip strength and slow walking speed because purpose has been linked with a range of positive health behaviors and biological processes that are potentially protective against declining physical function. However, the association between purpose in life and objective physical function has not been examined.

OBJECTIVE

To assess whether higher purpose in life among adequately functioning older adults is associated with lower risk of developing weak grip strength and slow walking speed over time.

DESIGN, SETTING, AND PARTICIPANTS

Data for a longitudinal cohort study were collected in 2006 and again in 2010 from the Health and Retirement Study, a nationally representative study of US adults older than 50 years. Data analysis was conducted from November 23, 2016, to June 2, 2017.

MAIN OUTCOMES AND MEASURES

The risk of developing weak grip strength (assessed as a binary yes or no outcome) or slow walking speed (yes or no) during the 4-year follow-up period. Grip strength was assessed using Smedley spring-type hand dynamometers, and walking speed was assessed by asking respondents to walk 2.5 m at their normal walking pace.

RESULTS

In this study, 4486 adults had grip scores at baseline indicating adequate function (2665 women and 1821 men; mean [SD] age, 63.0 [8.2] years) and 1461 adults had walking scores at baseline indicating adequate function (801 women and 660 men; mean [SD] age, 70.8 [6.5] years). After controlling for sociodemographic factors, each 1-SD increase in purpose was associated with a 13% decreased risk (95% CI, 1%-23%) of developing weak grip strength and a 14% decreased risk (95% CI, 8%-20%) of developing slow walking speed. Associations with walking speed were maintained in all covariate models (fully adjusted model: risk ratio, 0.89; 95% CI, 0.83-0.95), but associations with grip strength did not reach conventional levels of statistical significance after additionally adjusting for relevant baseline health factors, depressive symptoms, and health behaviors (fully adjusted model: risk ratio, 0.91; 95% CI, 0.80-1.04).

CONCLUSIONS AND RELEVANCE

Purpose in life was prospectively associated with a decreased risk of developing weak grip strength and slow walking speed, although the findings were more robust for walking speed than for grip strength. These findings suggest that a sense of purpose in life, a modifiable factor, may play an important role in maintaining physical function among older adults.