Loneliness, Social Isolation, and Cardiovascular Health

Voluntary exercise is a moderately effective mitigator of chronic social isolation stress in two female rodent models

Depression is a common mood disorders, particularly among women, and often with social stress precursors. Exercise, in addition to the known physical benefits, can have psychological benefits, potentially alleviating certain symptoms of stressors. This study investigated the impact of chronic social isolation stress in two female rodent models - mice and prairie voles. To assess the mitigating impact of exercise, paired and isolated animals were either provided 24-hour access to running wheels in their cages or remained sedentary. In mice, only animals that remained paired and had access to exercise wheels retained adaptive levels of active behaviors in the forced-swim test. However, either remaining paired or having access to a running wheel prevented increased corticosterone levels in mice. By contrast, in voles, either being paired or having access to a running wheel promoted adaptive levels of active behaviors in the forced-swim test. Similar to mice, either being paired or having access to a running wheel also prevented increased corticosterone levels in prairie voles. Body weight and adrenal:body mass ratios were not affected by either isolation or exercise in either species. Together these findings highlight the important differences between female rodents of different species in responses to chronic social stress. They also allude to differences between female and male rodent models. Lastly, these results indicate that for female rodents, exercise can provide certain mitigating effects against chronic social stress consequences.

Heart rate increases during social isolation: matter of depressive mood and self-reported infection symptoms

While the mental health challenges posed by quarantine are well-documented, its physiological effects remain less understood. We examined cardiovascular trajectories over a 6-day quarantine following common cold infection, utilizing data from the Pittsburgh Cold Study 3 (n=213, 2007-2011). Specifically, we explored the relationship between depressive mood and heart rate (HR) patterns, hypothesizing that individuals prone to depressive mood might experience altered arousal during quarantine. We conducted similar analyses for blood pressure (BP) as well. Our findings revealed that, on average, HR increased during quarantine. Notably, individuals reporting higher depressive mood levels exhibited lower initial HR but experienced a sharper increase throughout the quarantine period. In contrast, no significant linear or quadratic changes were observed in systolic blood pressure (SBP). However, initial analyses did identify significant linear changes in diastolic blood pressure (DBP) and mean arterial pressure (MAP). These changes in DBP and MAP were not influenced by depressive mood and lost significance in sensitivity analyses that accounted for infection-related factors, health behaviors, and socio-demographic variables. Interestingly, HR trajectories remained significant in sensitivity analyses but lost significance when self-reported symptoms were included. Self-reported symptoms partially mediated the relationship between depressive mood and HR increases, suggesting that individuals with higher depressive tendencies also reported more infection-related symptoms, contributing to increased HR. These findings highlight how midterm social isolation can elevate HR, particularly in individuals prone to depressive mood. However, the absence of a control group limits broader interpretations, emphasizing the need for further research.

Combined effects of social health and long-term exposure to fine particulate matter on cardiovascular disease in Chinese middle-aged and older adults

PURPOSE

Social isolation, loneliness, and fine particulate matter (PM2.5) exposure are significant social and environmental factors that frequently cooccur in vulnerable populations. The joint effects of these factors on the risk of cardiovascular disease (CVD), however, are not well supported by data. This study aimed to evaluate the independent and combined effects of social isolation, loneliness, and long-term PM2.5 exposure on CVD risk and to assess the interactions between social isolation or loneliness and PM2.5 exposure on CVD risk.

METHODS

We used Cox proportional hazards models to estimate the independent and combined effects of loneliness, social isolation, and long-term PM2.5 exposure on CVD incidence. We also conducted interaction analyses to investigate whether the effects of social factors on CVD are modified by the level of PM2.5 exposure.

RESULTS

This study included 12,544 participants, with mean age of 58.7 ± 9.4 years. The median follow-up was 7 years, with 1761 CVD events occurred. Individuals with loneliness presented a 29% increased risk of CVD (hazard ratio [HR] = 1.290, 95% confidence intervals [CI]: 1.165-1.428). A 10 µg/m3 increase in PM2.5 exposure was associated with a 6% increase in CVD risk (HR = 1.060, 95% CI: 1.028-1.092). A significant additive interaction effect was observed between loneliness and PM2.5 on CVD (P for additive interaction = 0.042).

CONCLUSION

Among Chinese middle and older adults, loneliness and long-term PM2.5 exposure had combined effects on CVD risk. The public health consequences of high PM2.5 exposure are more pronounced among individuals who experience feelings of loneliness.

Association of social isolation and loneliness with incident cardiovascular diseases: results from a nationally prospective cohorts in China

AIMS

Social isolation and loneliness are associated with increased risk of cardiovascular disease (CVD). Most research examining the effects of social isolation and loneliness on CVD is based in Western countries. This study examined the effects of loneliness and social isolation on cardiovascular disease in China.

METHODS

Data were derived from the China Health and Retirement Longitudinal Study (CHARLS). Social isolation, loneliness and CVD were measured at baseline. The analytical sample size was 6,860 for the analysis of self-reported CVD. Cox proportional-hazard regression adjusted for confounding factors were used to assess the association between baseline isolation, loneliness, and CVD.

RESULTS

Incident CVD was followed-up from 2011 to 2018. During the 7 years of follow-up, we found that loneliness was associated with an increased risk of CVD events (adjusted HR, 1.24; 95% CI, 1.06-1.44). In the moderately isolated group, loneliness was significantly associated with an elevated risk of incident CVD after adjusting for all confounders (adjusted HR, 1.40; 95% CI, 1.13-1.73). Loneliness was significantly associated with an increased risk of incident CVD among female participants (adjusted HR, 1.29; 95% CI, 1.07-1.56).

CONCLUSIONS

Loneliness significantly increased the risk of incident CVD, while social isolation did not exhibit a similar correlation. Our findings suggest that targeted and practical social interventions could improve the accuracy and efficiency of identifying individuals at high risk.

Exome sequencing identifies protein-coding variants associated with loneliness and social isolation

BACKGROUND

Loneliness and social isolation are serious yet underappreciated public health problems, with their genetic underpinnings remaining largely unknown. We aimed to explore the role of protein-coding variants in the manifestation of loneliness and social isolation.

METHODS

We conducted the first exome-wide association analysis on loneliness and social isolation, utilizing 336,115 participants of white-British ancestry for loneliness and 346,115 for social isolation. Sensitivity analyses were performed to validate the genetic findings. We estimated the genetic burden heritability of loneliness and social isolation and provided biological insights into them.

RESULTS

We identified six novel risk genes (ANKRD12, RIPOR2, PTEN, ARL8B, NF1, and PIMREG) associated with loneliness and two (EDARADD and GIGYF1) with social isolation through analysis of rare coding variants. Brain-wide association analysis uncovered 47 associations between identified genes and brain structure phenotypes, many of which are critical for social processing and interaction. Phenome-wide association analysis established significant links between these genes and phenotypes across five categories, mostly blood biomarkers and cognitive measures.

LIMITATIONS

The measurements of loneliness and social isolation in UK Biobank are brief for these multi-layer social factors, some relevant aspects may be missed.

CONCLUSIONS

Our study revealed 13 risk genes associated with loneliness and 6 with social isolation, with the majority being novel discoveries. These findings advance our understanding of the genetic basis of these two traits. The study provides a foundation for future studies aimed at exploring the functional mechanisms of these genes and their potential implications for public health interventions targeting loneliness and social isolation.

Gender differences in the mediating effects of social participation and number of children on psychological resilience and cognitive function in older adults

The aim of this study is to explore the relationship between the number of children of older adults in China and their cognitive function. A total of 15862 older adults were included in the 2017-2018 China Health and Longevity Longitudinal Survey(CLHLS), and were explored using Structural Equation Modeling(SEM) and restricted cubic splines(RCS). Research has found that social participation and psychological resilience have a moderating effect on the impact of child numbers on cognitive function, with a greater impact observed in female participants. RCS shows a U-shaped relationship between the number of children and poorer cognitive outcomes, but low fertility rates are only associated with poorer cognitive function in women. Cognitive function decreases with decreasing social participation and psychological resilience. To combat cognitive decline in older adults with multiple children, it is imperative to take into account the societal and psychological impacts and to integrate a suite of complementary intervention strategies.

Loneliness and repetitive negative thinking mediate the link between social health and cardiac distress in heart disease patients

Cardiovascular diseases are the leading cause of mortality worldwide, contributing to one-third of global deaths. Beyond physical health, heart disease is associated with cardiac distress, an emotional response that can negatively impact recovery and well-being. Understanding the psychological and social mechanisms underlying cardiac distress is crucial for improving patient outcomes. This study examines how social health (social support and social isolation) influences cardiac distress, with loneliness and repetitive negative thinking as mediators. To evaluate a theoretical model linking social health to cardiac distress, mediated by loneliness and repetitive negative thinking in patients with heart disease. A cross-sectional, correlational study was conducted in 2024 with 400 cardiac patients from two hospitals and one private clinic in Amol, Iran. Participants completed validated questionnaires assessing cardiac distress, social support, social isolation, loneliness, and repetitive negative thinking. Structural equation modeling was used for data analysis. Social isolation (r = 0.47, p < 0.001) and repetitive negative thinking (r = 0.50, p < 0.001) were significantly associated with greater cardiac distress. Social support negatively predicted both loneliness (β = - 0.32, p < 0.001) and cardiac distress (β = - 0.25, p < 0.01). Indirect effects showed that social support reduced cardiac distress by decreasing loneliness and repetitive negative thinking (β = - 0.23, p < 0.01), while social isolation increased cardiac distress through its influence on loneliness and repetitive negative thinking (β = 0.18, p = 0.05). The model explained 47.4% of the variance in cardiac distress. These findings highlight the importance of social health in managing cardiac distress among heart disease patients. Strengthening social support may alleviate loneliness and reduce repetitive negative thinking, ultimately improving emotional well-being and health outcomes. Future research should explore targeted interventions addressing these psychosocial factors to effectively reduce cardiac distress.

Loneliness, Methamphetamine Use, and Cardiovascular Risk Factors Among Sexual Minority Men in the COVID-19 Era

BACKGROUND

Important gaps exist in our understanding of loneliness and biobehavioral outcomes among sexual minority men (SMM), such as faster HIV disease progression. At the same time, SMM who use methamphetamine are approximately one-third more likely than non-users to develop cardiovascular disease. This study examined associations of loneliness, stimulant use, and cardiovascular risk in SMM with and without HIV.

METHOD

Participants were enrolled from August 2020 to February 2022 in a 6-month prospective cohort study. The study leveraged self-report baseline data from 103 SMM, with a subset of 56 SMM that provided a blood sample to measure markers of cardiovascular risk.

RESULTS

Loneliness showed negative bivariate associations with total cholesterol and LDL cholesterol in the cardiometabolic subsample (n = 56). SMM with methamphetamine use (t(101) = 2.03, p < .05; d = .42) and those that screened positive for a stimulant use disorder (t(101) = 2.07, p < .05; d = .46) had significantly higher mean loneliness scores. In linear regression analyses, negative associations of loneliness with LDL and total cholesterol were observed only among SMM who used methamphetamine.

CONCLUSION

We observed lower cholesterol in SMM reporting loneliness and methamphetamine use. Thus, in addition to the observed associations of loneliness with cholesterol, there are important medical consequences of methamphetamine use including cardiovascular risk, higher HIV acquisition risk and progression, as well as stimulant overdose death. This cross-sectional study underscores the need for clinical research to develop and test interventions targeting loneliness among SMM with stimulant use disorders.

Chronic loneliness and longitudinal changes in cognitive functioning

BACKGROUND

Loneliness is a worldwide concern with significant health implications that may be a significant risk factor for Alzheimer's disease and related dementias. In light of the importance of detecting early cognitive changes and risk factors influencing cognitive health, this study examined whether chronic loneliness predicted cognitive changes among young and middle-aged adults.

METHODS

This study utilizes data from a longitudinal measurement burst study spanning over two years, comprising three waves of data collection. A systematically recruited young to mid-life adult sample (25- 65 years) included 172 racially and economically diverse participants who provided information about loneliness for at least two consecutive waves. Chronic loneliness was defined based on the validated multi-item PROMIS Social Isolation scale. We assessed working memory, processing speed, and spatial memory in a measurement burst design using mobile cognitive assessments. Multilevel growth models were conducted to examine whether chronic loneliness was associated with changes in cognitive performance during the study period of up to two years.

RESULTS

Results revealed that chronic loneliness was not associated with baseline performance of working memory, processing speed, spatial memory or global cognitive performance, but chronic loneliness was associated with differential cognitive trajectories, specifically a lack of retest related improvement. There were no significant changes in cognitive performance for the chronic loneliness group across waves, whereas significant improvements were observed in those who were not chronically lonely.

CONCLUSIONS

This study offers insights into the impact of chronic loneliness on cognitive changes in young and middle-aged adults, revealing that chronically lonely individuals did not exhibit the practice-related improvements that are commonly observed in longitudinal studies. Findings suggest the potential significance of identifying and addressing chronic loneliness promptly to prevent potential cognitive consequences of chronic loneliness.

The mediating effects of sleep quality in the relationship between loneliness and depression among middle-aged and older adults

Loneliness has long been recognized as a key predictor of depression in older adults, and both are related to sleep quality. However, to this day, less is known about whether sleep quality mediates their relationship. This study aimed to examine the relationship between loneliness, sleep quality, and depressive symptoms, and to further explore whether sleep quality mediates the relationship between loneliness and depressive symptoms. Using the random cluster sampling method, 1016 permanent residents aged 45 and above in Ankang City, Shaanxi Province were selected. The relationship between loneliness, sleep quality, and depressive symptoms was analyzed using binary logistic regression, and the mediating role of sleep quality between loneliness and depressive symptoms was analyzed using the PROCESS macro in SPSS 25.0 software. The average age of the participants in this study was 60.39 ± 8.50. Regression analyses showed that individuals with loneliness (OR 7.161, 95%CI: 4.889-10.490, P < 0.001) and those with poor sleep quality (OR 4.777, 95%CI: 3.301-6.913, P < 0.001) were more likely to experience depressive symptoms than individuals without loneliness and with good sleep quality. This study also found a significant mediating effect of sleep quality between loneliness and depressive symptoms [effect value = 0.066, bootstrap 95% CI: (0.037, 0.093)] with an effect size of 13.31%. Loneliness may lead to reduced sleep quality in individuals, which in turn may lead to or exacerbate depressive symptoms. Therefore, this study highlights the importance of assessing and improving sleep quality in lonely people.

The regulatory role of ACP5 in the diesel exhaust particle-induced AHR inflammatory signaling pathway in a human bronchial epithelial cell line

Exposure to diesel exhaust particles (DEPs), which are major constituents of urban air pollution, is associated with adverse health outcomes. Previous studies have shown that DEPs enhance the expression of pro-inflammatory cytokines and immune responses. However, few studies have focused on genomic variants that regulate DEP-induced signaling. Here, we identify a frequently found genomic variant, ACP5, in allergic diseases, and establish an ACP5 knock-out (KO) human bronchial epithelial cell line (BEAS-2B) using CRISPR/Cas9 editing to mimic the ACP5 mutation. DEP-induced apoptosis and intracellular reactive oxygen species (ROS) were significantly increased in the ACP5 KO cells compared with controls, suggesting that ACP5 KO cells were at increased risk from DEP exposure. A gene expression profile revealed an activated aryl hydrocarbon receptor (AHR)-CYP1A1 axis followed by upregulated pro-inflammatory signaling. Treatment of a DEP-exposed ACP5 KO BEAS-2B conditioned medium (CM) supernatant induced an inflammatory response and tissue damage in mice, and AHR inhibition effectively prevented inflammation-induced damage, suggesting that AHR-CYP1A1-inflammatory signaling is a prominent mechanism responsible for detrimental effects. Collectively, our findings reveal a novel link between ACP5 KO and the AHR-CYP1A1 inflammatory signaling pathway in DEP-exposed cells, and identify the AHR-CYP1A1 axis as a potential therapeutic target in individuals suffering from DEP-induced toxicity, particularly those with ACP5 mutations.

Association of polysocial risk score, cardiovascular health status, and the risk of premature mortality: Findings from the UK Biobank

BACKGROUND

Evidence of the cumulative effects of social risk factors on premature mortality is quite limited. We aimed to examine the association between cumulative social risk factors and premature mortality by constructing a polysocial risk score, and to explore the influence of cardiovascular health on this association.

METHODS

A polysocial risk score was constructed by summing 11 social determinants of health. A cardiovascular health (CVH) score was calculated following the algorithm of "Life's Essential 8". Premature mortality was defined as death at an age younger than 75. Cox proportional hazards model was conducted.

RESULTS

A total of 314,039 participants in the UK Biobank were included (median age 56.0 years, 53.1% women). During a median of 12.7 years of follow-up, 13,888 premature deaths were reported. Compared with participants who had a low polysocial risk score (≤3), participants with a high polysocial risk score (≥7) were more than twice as likely to die prematurely in the follow-up period (HR 2.18, 95% CI 2.06-2.30). Compared with participants with ideal CVH and low polysocial risk score, those with poor CVH and high polysocial risk score had the highest risk of premature mortality (HR 5.25, 95% CI 4.48-6.14). A significant interaction was found between CVH status and polysocial risk score on premature mortality risk (P for interaction <0.001).

CONCLUSIONS

Polysocial risk score was associated with an increased risk of premature mortality, the association was exacerbated by poor CVH. Our findings indicate that limiting social inequities and encouraging people to achieve an ideal CVH are essential to reducing the burden of premature mortality.

Recognising and addressing loneliness and social isolation in older people

Loneliness is widely recognised as a problematic issue in UK society. Older people are particularly vulnerable to loneliness and social isolation for various reasons, and the effects of these can be detrimental to their physical and mental health and well-being. Recognising the signs and symptoms associated with loneliness and social isolation is central to beginning the process of assessment and intervention. This article describes the concepts of loneliness and social isolation and explores their link to physical and mental health. The author also discusses some ways in which nurses can measure loneliness and provides some examples of interventions, such as health coaching and social prescribing, which can help to reduce the experiences of loneliness and social isolation in older people.

Understanding social integration and health outcomes among China's internal migrants: a systematic review

Background

The internal migrant populations in China have contributed significantly to the country's social and economic landscape, yet health disparities among migrants remain a pressing concern. Social integration is considered a critical factor influencing health outcomes, but evidence on this relationship is fragmented. This systematic review aims to synthesize existing studies to explore the association between social integration and health outcomes, including healthcare service utilization, self-reported health (SRH), and non-communicable disease (NCD), among internal migrants in China.

Methods

A systematic search was conducted across three databases (PubMed, EMBASE, PsycINFO) to identify studies published from January 2014 to November 2024 according to the protocol (INPLASY2024110085). The JBI assessment tool was used to assess the quality of the included studies.

Results

A total of 16 eligible cross-sectional studies were identified, focusing on the multidimensional aspects of social integration, including economic integration, acculturation, social networks and self-identity and their influence on health outcomes. Eleven papers focused on health service utilization, four concentrated on SRH and one discussed both NCDs and SRH. The majority of included studies indicated a significantly positive association between social integration and health outcomes of internal migrants.

Conclusion

Social integration plays a crucial role in addressing health disparities among internal migrants in China. This review emphasizes the need for initiatives at all levels to enhance economic inclusion, cultural adaptation, and social networks to foster better social integration for the migrant community. Addressing these gaps will promote equitable healthcare access and improve the wellbeing of internal migrants in China.

Systematic review registration

Identifier INPLASY2024110085, https://inplasy.com/inplasy-2024-11-0085/.

Relationship quality and educational attainment links to development of cardiometabolic morbidity and multimorbidity across middle adulthood

The prevalence of cardiometabolic morbidity (e.g., high blood pressure, heart attack, stroke, type 2 diabetes) and multimorbidity development (2 or more cardiometabolic morbidities) are rapidly growing in the US. Cardiometabolic morbidity and multimorbidity are linked to poor well-being outcomes, high healthcare costs, and mortality. There is little known about cardiometabolic multimorbidity health disparities, particularly regarding mutable factors that might be targeted in future health interventions. In the present study, using a biopsychosocial framework (Biobehavioral Family Model), we examine whether cardiometabolic morbidity and multimorbidity development are linked to premorbid family and marital relationships and if it differs depending on socioeconomic status (i.e., educational attainment) using three waves of Midlife in the US (N = 4951). We assessed cardiometabolic development with three conceptualizations: number of cardiometabolic morbidities (i.e., count variable), individual cardiometabolic morbidities (i.e., diabetes, high blood pressure, stroke, heart attack), and severity of cardiometabolic multimorbidity (e.g., 3+ vs. zero morbidities). Family strain increased the number of cardiometabolic morbidities (OR = 1.17) and the severity of multimorbidity (e.g., 3+ morbidities: OR = 1.38). People with a high school education experienced family support as a buffer to the negative health impact of education level. Generally, marital quality appeared less impactful on cardiometabolic morbidity and multimorbidity development compared to family strain. Positive and negative family characteristics appear to function differently across educational attainment. These findings indicate that adults' non-intimate family relationships predict important outcomes such as diabetes, heart attack, stroke, and cardiometabolic multimorbidity and should be considered targets for preventative health interventions.

The association between exercise, activities, and frailty in older Chinese adults: a cross-sectional study based on the Chinese Longitudinal Healthy Longevity Survey (CLHLS) data

OBJECTIVES

The purpose of this study was to evaluate the association between exercise/activities and frailty in older Chinese adults using the Chinese Longitudinal Healthy Longevity Survey (CLHLS).

METHODS

This cross-sectional study included 6862 participants aged 65 years or older from the CLHLS 2018. Frailty was assessed using a 38-variable frailty index (FI). Activities included Tai chi, square dance, garden work, raising animals/pets, playing cards/mah-jongg, social activity and housework. Multivariate logistic regression was used to assess the association between exercise/activities and frailty, adjusting for covariates such as gender, age, BMI, chronic diseases, residence, education, co-residence, economic status, smoking, drinking, physical labor history, and nutritional supplements.

RESULTS

The mean age of this study was 81.5 (SD = 10.3)years, with 3567 (52%) females. Frailty prevalence was 32.3%. The prevalence of exercise and daily activities was 31% and 78.6%, respectively. Multivariate logistic regression analysis showed that the likelihood of frailty increased with decreased exercise (OR = 1.85, 95% CI: 1.57, 2.18, P < 0.001) and activities (OR = 4.43, 95% CI: 3.74, 5.25, P < 0.001).

CONCLUSIONS

Participation in exercise/activities is associated with a lower likelihood of frailty. Regular housework may also contribute to reducing frailty risk.

Loneliness Within a Romantic Relationship: Do Gratitude and Forgiveness Moderate Between Loneliness and Relational and Sexual Well-Being?

Loneliness has a detrimental effect on relational and sexual well-being. Recent research indicates that gratitude and forgiveness are two qualities that may buffer negative factors in relationships. We examine whether these two qualities may moderate the negative association between loneliness and relational and sexual well-being. Using data from a nationally representative study of newlywed couples (N = 1,614) in the U.S. (CREATE), we evaluated whether actor and partner gratitude and forgiveness moderated the negative association between loneliness and sexual and relational well-being. Results indicated that both the husband's and wife's gratitude and forgiveness moderated the negative association between loneliness and relational well-being, but we found no moderation effect for sexual well-being. These findings may indicate that while gratitude and forgiveness protect the marriage relationship from feelings of loneliness, the sexual relationship is not protected from loneliness through forgiveness and gratitude alone. This study provides initial evidence that when spouses experience loneliness, forgiveness and gratitude may create pro-relational motivation attitudes and behaviors within the marriage relationship. Therapeutic implications are discussed.

Social isolation and loneliness increase the risk of coronary heart disease: Insights from a prospective cohort study

Social isolation and loneliness are associated with an increased risk of various diseases and all-cause mortality. Coronary heart disease (CHD) is the main cause of heart disease deaths worldwide, which affects people's quality of life and longevity. However, the causal relationship between social isolation, loneliness, and CHD remains uncertain. This study aims to explore the potential impacts of social isolation and loneliness on the risk of CHD, thereby helping identify those most susceptible to these conditions. A total of 442,811 individuals (mean and sd of age = 56.24 ± 8.07, 55.8% women, 91.5% white) were included in the study. The UK Biobank cohort study documented 25,120 CHD cases during a mean follow-up of 14.77 years. The relationship between loneliness, social isolation and CHD were first examined using the COX proportional risk model. A two-sample Mendelian randomization (MR) study was then conducted to further the association. We found that the hazard ratio (95% CI) of coronary heart disease (CHD) when comparing the most socially isolated groups to the least was 1.15 (1.05-1.26; P = 0.0017). Additionally, the hazard ratio (95% CI) for comparing the presence of loneliness to its absence was 1.15 (1.10-1.20; P < 0.001).Subgroup analyses showed that the risk of CHD was higher in individuals with low sleep quality who experienced social isolation and in women who experienced loneliness. MR analyses further revealed that individuals who felt lonely (OR = 1.03; 95% CI: 1.01,1.06) and those less involved in sports/social activities (OR = 1.02; 95% CI: 1.00,1.04) had a higher likelihood of developing CHD. MR provided further evidence supporting the causal relationship between social isolation, loneliness and CHD risk. Our findings suggest a significant association between social isolation, loneliness and increased risk of coronary heart disease. These findings suggest that both social isolation and loneliness are critical risk factors for CHD.

Association of Social Isolation and Plasma Metabolites With the Risk of Venous Thromboembolism

BACKGROUND

To explore the association of social isolation with venous thromboembolism (VTE) risk and the mediating role of metabolomics on this association.

METHODS

Overall, 236 026 participants free of VTE and with complete metabolomics data at baseline from the UK Biobank were included. Social isolation was constructed based on the frequency of friend/family visits, weekly group activities, and living alone. The study outcome was incident VTE, including deep vein thrombosis or pulmonary embolism. Least absolute shrinkage and selection operator regression was applied to create a social isolation-associated metabolic signature. We estimated hazard ratios of study outcomes in relation to social isolation/metabolic signature and calculated the proportion of social isolation-VTE association mediated by the metabolic signature.

RESULTS

During a median follow-up of 12.5 years, 6681 VTE cases were recorded. Social isolation was positively associated with VTE risk (versus without social isolation; hazard ratio, 1.17 [95% CI, 1.09-1.27]). A metabolic signature for social isolation was constructed using 28 metabolites. This metabolic signature showed significant association with VTE risk (per SD increment; hazard ratio, 1.16 [95% CI, 1.13-1.19]) and mediated 11.0% (95% CI, 7.0-19.8) of the increased VTE risk associated with social isolation. 11 metabolites in the metabolic signature also significantly mediated the association between social isolation and VTE risk, with mediation proportions ranging from 0.5% to 2.6%. Similar results were found for incident deep vein thrombosis and pulmonary embolism, respectively.

CONCLUSIONS

Social isolation was positively associated with VTE risk. The metabolic signature for social isolation, especially the 11 major metabolites included, significantly mediated the association between social isolation and VTE risk.

The Role of Beauty Salons in Community Health Promotion: Exploring Health Engagement and Social Connectivity in Japanese Hair Salons

Introduction Beauty salons serve as more than just spaces for personal grooming; they are social hubs that facilitate interpersonal connections. Given the increasing importance of social engagement in public health, beauty salons may have a role in promoting health awareness and reducing social isolation. While international studies have demonstrated the effectiveness of salon-based health interventions, there is limited research on the role of Japanese beauty salons in community health promotion. This study aims to explore health-related conversations and awareness among hairstylists in Japan. Method A survey-based study was conducted at Hair Lab En Luce, a beauty salon in Matsue City, Japan. Five hairstylists and assistants recorded customer interactions over one month in June 2022. The survey collected data on customer demographics, conversation topics, hairstylists' emotional responses, and perceived actions for future engagement. Thematic analysis was employed to identify key themes related to health engagement. Results A total of 127 survey responses were analyzed. Health-related topics constituted 27.6% of conversations, demonstrating hairstylists' engagement in customers' well-being. Thematic analysis revealed three key themes: continuity with customers, trust-based customer-hairstylist relationships, and the expanding role of beauty salons in health promotion. Hairstylists often provided informal health advice and observed scalp and skin conditions, occasionally referring customers to healthcare professionals. Conclusion Japanese beauty salons function as spaces for both personal care and social support. Strengthening collaborations between hairstylists and healthcare providers may enhance their role in community health promotion. Future research should assess the effectiveness of salon-based health interventions in Japan.

Interventions by Cardiovascular Drugs Against Aircraft Noise-Induced Cardiovascular Oxidative Stress and Damage

Noise pollution is a known health risk factor and evidence for cardiovascular diseases associated with traffic noise is growing. At least 20% of the European Union's population lives in noise-polluted areas with exposure levels exceeding the recommended limits of the World Health Organization, which is considered unhealthy by the European Environment Agency. This results in the annual loss of 1.6 million healthy life years. Here, we investigated the protective effects of cardiovascular drug interventions against aircraft noise-mediated cardiovascular complications such as elevated oxidative stress or endothelial dysfunction. Using our established mouse exposure model, we applied mean sound pressure levels of 72 dB(A) for 4 d. C57BL/6 mice were treated with the beta-blocker propranolol (15 mg/kg/d s.c. for 5 d) or the alpha-blocker phenoxybenzamine (1.5 mg/kg/d s.c. for 5 d) and noise-exposed for the last 4 d of the drug administration. Short-term noise exposure caused hypertension (measured by tail-cuff blood pressure monitoring) and impaired endothelial function (measured by isometric tension recording in the aorta and video microscopy in cerebral arterioles in response to acetylcholine). Noise also increased markers of oxidative stress and inflammation. Treatment of mice with propranolol and phenoxybenzamine prevented endothelial and microvascular dysfunction, which was supported by a decrease in markers of inflammation and oxidative stress in heart tissue and the brain. Amelioration of noise-induced hypertension (systolic blood pressure) was not observed, whereas pulse pressure was lowered by trend. This study provides a novel perspective mitigating the adverse effects of noise pollution, especially in vulnerable groups with medication, a rationale for further pharmacological human studies.

Psychosocial wellbeing and risk perception of older adults during COVID-19 pandemic in Nigeria: perspectives on the role of social workers

Background

The COVID-19 pandemic presented a 'double-edged sword' for older adults: not only were they more susceptible to the virus, but its broader consequences also exacerbated other challenges, particularly those related to psychosocial well-being. Limited evidence exists on how older adults perceive the pandemic and its impact on their well-being and the role of social workers in addressing these challenges, particularly in resource-limited settings like Nigeria.

Aim

This study explored older adults' perceived risks regarding COVID-19, its impact on their psychosocial well-being, and the role of social workers in addressing these challenges in Nigeria.

Methods

A phenomenological and exploratory research design was used. In-depth interviews (IDIs) were conducted with 16 older adults and 4 social workers in Onitsha metropolis, Anambra State, Southeast Nigeria. Data were analyzed through reflexive thematic analysis.

Results

The findings revealed that the COVID-19 restrictive measures negatively impacted the psychosocial well-being of older adults, where social isolation, lack of support, the inability to engage in wellbeing activities, and emotional trauma collectively contributed to a significant decline in their mental and emotional health. Additionally, widespread misconceptions about the origin of COVID-19 led to reluctance in adopting preventive measures. While social workers provided some awareness and counselling sessions, their involvement was limited. Social workers were not recognized as part of the frontline response team, and their efforts were primarily constrained by governmental and institutional neglect.

Conclusion

The findings highlight the need for policy initiatives to enhance social workers involvement in strengthening the psychosocial resilience of older adults and addressing misconceptions during public health emergencies. Comprehensive strategies are essential for safeguarding the psychosocial well-being of older adults in future pandemics or similar crises.

Social Bonds Retain Oxytocin-Mediated Brain-Liver Axis to Retard Atherosclerosis

BACKGROUNDS

Social interaction with others is essential to life. Although social isolation and loneliness have been implicated as increased risks of cardiometabolic and cardiovascular diseases and all-cause mortality, the cellular and molecular mechanisms by which social connection maintains cardiometabolic and cardiovascular health remain largely unresolved.

METHODS

To investigate how social connection protects against cardiometabolic and cardiovascular diseases, atherosclerosis-prone, high-fat diet-fed Apoe-/- mouse siblings were randomly assigned to either individual or grouped housing for 12 weeks. Histological, flow cytometric, biochemical, gene, and protein analyses were performed to assess atherosclerotic lesions, systemic metabolism, inflammation, and stress response. The effects of oxytocin on hepatocytes and subsequent cardiometabolic and cardiovascular function were investigated by in vivo and in vitro approaches.

RESULTS

Apoe-/- mice housed individually developed larger vulnerable atherosclerotic lesions by disrupted lipid metabolism compared with those of mice in regular group housing, irrespective of body weight, eating behavior, feeding conditions, sympathetic nervous activity, glucocorticoid response, or systemic inflammation. Mechanistically, the chronic isolation reduced the hypothalamic production of oxytocin, which controls bile acid production and LPL (lipoprotein lipase) activity through the peripheral OXTR (oxytocin receptor) in hepatocytes, whose downstream targets include Cyp7a1, Angptl4, and Angptl8. While hepatocyte-specific OXTR-null mice and mice receiving adeno-associated virus targeting OXTR on hepatocytes led to severe dyslipidemia and aggravated atherosclerosis, oral oxytocin supplementation to socially isolated mice, but not to hepatocyte-specific OXTR conditional knockout mice, improved lipid profiles and retarded atherosclerosis development.

CONCLUSIONS

These results identify a novel brain-liver axis that links sociality to hepatic lipid metabolism, thus proposing a potential therapeutic strategy for loneliness-associated atherosclerosis progression.

Social isolation increases impulsive choice with minor changes on metabolic function in middle-aged rats

The effects of social isolation (SI) during middle age remain unclear, so we tested the hypothesis that SI would lead to an increase in impulsive choice (IC), anxiety-like behavior, and metabolic dysfunction in middle-aged rats. Male and female rats were housed individually or in groups of four with same-sex housing mates at 11 months of age. Two months later, IC behavior was assessed using a delay-discounting task and anxiety-like behavior through a novelty-suppressed feeding (NSF) task. Lastly, glucose tolerance and insulin sensitivity following exposure to a high-fat diet were assessed using an oral glucose tolerance test (OGTT) and an insulin tolerance test (ITT). The results showed that socially isolated rats displayed more IC behavior than did group-housed rats of both sexes. However, no significant effect of housing was evident in the NSF task, OGTT, or ITT. Male rats had a higher plasma insulin concentration and insulin resistance index compared to females. Our findings demonstrate that SI in middle age is sufficient to increase IC behavior and highlight inherent sex-specific differences in metabolic profiles. These findings underscore the importance of investigating mechanisms that underlie the effects of social isolation during different stages of life.

Deleterious effects of social isolation on neuroendocrine-immune status, and cancer progression in rats

Accumulating evidence indicates that social isolation (SI) in humans and rodents is associated with increased cancer incidence and mortality, yet mediating mechanisms remain elusive. Here, we examine the neuroendocrine and immunological consequences of SI and its short- and long-term physiological impacts in naïve and cancer-bearing rats. Findings indicate that isolated animals experienced a significant decrease in weight compared to controls. Specifically, females showed a marked weight decrease during the first week of isolation. Isolated rats had significantly higher numbers of MADB106 experimental pulmonary metastases. Although mortality rates were higher in isolated tumor-bearing rats, unexpectedly, they exhibited a reduced growth rate of orthotopically implanted MADB106 tumors. Transcriptomic analyses of these excised tumors indicated a major downregulation in the expression of various genes, including those associated with pro-metastatic processes (e.g., EMT). In naïve rats (no cancer), levels of IL-6 increased, and total IgG levels decreased under SI conditions. A mixed effect was found for TNFα, which increased in females and decreased in males. In the central nervous system, isolated rats showed altered gene expression in key brain regions associated with stress responses and social behavior. The paraventricular nucleus of the thalamus emerged as a significantly affected region, along with the bed nucleus of the stria terminalis. Changes were observed in the expression of oxytocin, serotonin, and dopamine receptors. Isolated rats also exhibited greater alterations in hypothalamic-pituitary-adrenal (HPA) axis-related regulation and an increase in plasma CORT levels. Our study highlights the profound impact of SI on metastatic processes. Additionally, the potential detrimental effects of SI on thermoregulation were discussed, emphasizing the importance of social thermoregulation in maintaining physiological stability and highlighting the need to avoid single-caging practices in research. We report neuro-immune interactions and changes in brain gene expression, highlighting the need for further research into these underlying processes to improve outcomes in animal models and potential interventions for cancer patients through increased social support.

Social isolation promotes tumor immune evasion via β2-adrenergic receptor

Social isolation is a recognized risk factor for tumor initiation and mortality, but the role and mechanisms responsible for social isolation on tumor progression are poorly understood. In this study, we found that social isolation contributed to accelerated tumor growth and induced a remodeling of the tumor immune microenvironment, resulting in immunosuppression. Mechanistically, social isolation triggered the activation of the sympathetic nervous system, leading to impaired CD8+ T cell antitumor immune responses by activating β-adrenergic receptor 2 (β2-AR), which highly expressed on tumor-infiltrating CD8+ T cells. Pharmacological inhibition of β2-AR signaling effectively enhanced CD8+ T cell anti-tumor immune responses and improved the efficacy of anti-PD-1 immunotherapy in the context of social isolation. Thus, our study uncovers a mechanism through which social isolation induces tumor immune evasion and offers potential directions for cancer immunotherapy in socially isolated patients.

Development of loneliness and social isolation after spousal loss: A systematic review of longitudinal studies on widowhood

BACKGROUND

Spousal loss is a stressful life event that is associated with loneliness and social isolation, both of which affect mental and physical health. The primary objective of this paper was to synthesize longitudinal studies that investigated loneliness and social isolation in widowhood.

METHODS

A systematic search of the literature was conducted using three electronic databases. 26 longitudinal studies published through June 2024 were included for further analysis. Participant characteristics, study design, and key findings were extracted.

RESULTS

Most studies were from the United States or Europe, included more widows than widowers, and assessed loneliness in older adults aged >60 years. Loneliness peaked directly following spousal death, but findings were inconsistent regarding the lasting effects of widowhood. Heterogeneity in the longitudinal trajectories of loneliness was noted, with studies showing linear increases, decreases, or curvilinear relationships over time. Several factors modified the relationship between widowhood and loneliness, including volunteerism, military experience, income, and age. Widowers consistently reported greater loneliness and worse social isolation when compared with widows. Few studies investigated social isolation specifically, but those that did found that social isolation may decrease in widowhood.

CONCLUSIONS

As the world grapples with a social pandemic of loneliness and social isolation, widowed adults may be uniquely affected. Few studies investigated the longitudinal trajectory of loneliness and especially social isolation in widowhood, and those that did found heterogenous results. Future work is needed to understand why some widowed adults are uniquely affected by feelings of loneliness and social isolation while others are not, and whether potentially modifiable factors that moderate or mediate this relationship could be leveraged by psychosocial interventions.

"Loneliness is killing me?!": the subjective emotional experience of loneliness during the COVID-19 pandemic: results of a cross-sectional study in patients with a psychiatric disorder

PURPOSE

During the COVID-19 pandemic, an increase in loneliness as well as mental health issues was detected. However, research on the association between loneliness and mental disorders is sparse. The aim of this study was to examine loneliness and associated social and emotional factors in patients with a psychiatric disorder and to investigate potential predictors of loneliness.

METHODS

Participants were N = 230 patients currently receiving psychiatric treatment at the Department of Psychiatry and Psychotherapy, University Hospital Leipzig, Germany. A cross-sectional survey included questionnaires on loneliness, life satisfaction, need to belong, interpersonal trust, stress, and resilience.

RESULTS

Most participants (n = 91, 39.6%) suffered from depression, followed by anxiety disorder (n = 43, 18.7%). Significantly higher loneliness levels compared to norm samples were detected in all three loneliness questionnaires (all p <.05), and overall n = 128 (57.7%) reported to feel lonely. In addition, participants reported lower life satisfaction, lower interpersonal trust, and lower resilience than the general population (all p <.05). No significant differences in loneliness levels between different psychiatric diagnoses were revealed. It was found that lower satisfaction with life, lower interpersonal trust and lower resilience were significantly associated with higher loneliness (all p <.05).

CONCLUSION

This study underlines the importance to continue research on loneliness in people with mental disorders after the COVID-19 pandemic since the majority of patients reported to feel lonely. Further, tailored therapy-accompanying interventions to prevent loneliness in patients with a psychiatric disorder should be designed and evaluated to meet patients' diverse needs e.g., through online programs.

TRIAL REGISTRATION

German Clinical Trial Registration: DRKS00023741 (registered on April 6, 2021).

Interventions to reduce social isolation and loneliness among minority ethnic populations in OECD countries: A scoping review

BACKGROUND

Social isolation and loneliness (SIL) are complex issues that impact mental and physical wellbeing and are significant public health concerns. People from minority ethnic backgrounds living in Organisation for Economic Cooperation and Development (OECD) member states may be particularly vulnerable to experiencing SIL. This is due to various challenges associated with life in foreign countries, including cultural differences, settlement issues, low incomes, and discrimination. While many interventions have been developed to address SIL in the general population, there is little information about interventions designed for minority ethnic populations in OECD countries. Our study aimed to 1) Investigate existing interventions for minority ethnic communities in OECD countries; 2) Assess how these interventions are conceptualised to increase awareness of SIL risks on health factors.3) Explore culturally sensitive approaches in these interventions, and 4) Identify the most effective interventions in reducing SIL in minority ethnic populations.

METHODS AND FINDINGS

We searched Medline, APA PsycINFO, Psychology and Behavioural Sciences Collection, CINAHL, Web of Science, and Scopus from their inception to September 19th, 2023, and registered the scoping review at https://osf.io/fnrvc. Our search yielded 10,479 results, of which 12 studies were included: five RCTs, six non-randomized quasi-experimental studies, and one qualitative study. Interventions were grouped into four main categories: social facilitation, befriending, leisure and skills development, and health education programmes. While only a few interventions targeted minority ethnic populations specifically, our findings highlight the potential of culturally sensitive interventions in reducing social isolation and loneliness among minority ethnic communities in OECD countries. However, given the type and extent of evidence, it is still unclear which interventions are superior in reducing SIL in minority ethnic populations in OECD countries. Further research is necessary to understand which activities may be most effective for which communities. Such interventions should be designed and tailored to account for the broader risk implications of SIL to raise awareness of the population's peculiar health risk profile.

DISCUSSION

Interventions designed to address SIL among minority ethnic groups in OECD member states are scarce and have not been designed to account for the health risks profile of the population. Integrated research designs involving groups linked with minority ethnic populations are needed to link individual, community, and societal factors alongside population risk profiles for increased recognition of SIL as an important health factor.

Comparing network structures of depressive and anxiety symptoms between demographically-matched heart disease and heart disease free samples using propensity score matching: Findings from the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

BACKGROUND

Older adults with heart disease often experience higher rates of comorbid anxiety and depression. This study examined depression and anxiety network structures among older adults with heart disease and their heart disease free peers.

METHODS

Network analyses of secondary cross-sectional data from the 2017 to 2018 wave of CLHLS were used to construct groups of older adults with and without heart disease using propensity score matching. Depression and anxiety symptoms were assessed using Center for Epidemiological Studies Depression Scale and Generalized Anxiety Disorder Scale, respectively. Central symptoms and bridge symptoms were identified using expected influence.

RESULTS

1689 older adults with heart disease and matched control sample of 1689 older adults without heart disease were included. The prevalence and severity of depression and anxiety were significantly higher in older adults with heart disease compared to the control group. There was no significant difference in overall structures of depression and anxiety network models between two the groups. Key central symptoms and bridge symptoms within these groups were highly similar; GAD 2 "Uncontrollable worrying" and GAD 4 "Trouble relaxing" were identified as the most central symptoms, while GAD 1 "Nervousness" and CESD 1 "Feeling bothered" were identified as key bridge symptoms across both network models.

CONCLUSION

Depression and anxiety are more prevalent in older adults with heart disease than demographically-matched heart disease free controls. However, network structures of these symptoms do not differ between two groups. Accordingly, depression and anxiety psychosocial interventions developed for older adults without heart disease may also benefit older adults with heart disease.

Physical activity and heart rate in PTSD inpatients: Moderation by custody of a service dog

Posttraumatic stress disorder is associated with autonomic hyperarousal often shown to involve elevated resting heart rate and, simultaneously if somewhat paradoxically, reduced physical activity. Both are risk factors for cardiovascular disease and so may contribute to its elevated prevalence in persons with this diagnosis. Epidemiological studies have observed dog owners to exhibit lower rates of cardiovascular disease. Non-randomized between-group studies have found service dog companionship to be associated with increased physical activity and with lower resting heart rate. A challenge to research in this area is its vulnerability to selection biases in group assignment which could lead to over-estimation of advantages or disadvantages associated with pet or service dog contact and companionship. The current study executed a within-subjects design investigating physical activity and heart rate in a sample of U.S. military Veterans engaged in residential treatment for PTSD and a concurrent service animal training intervention. A mean of 37 days of continuously-recorded day-time physical activity and heart rate were obtained from 45 participants. On days when they had custody of a familiar service-dog-in-training, participants exhibited increased physical activity accompanied by a small reduction in concurrent, activity-adjusted heart rate. Though observed in a specialized context, these short-term findings align with prior observations of lowered risk of cardiovascular disease in association with pet dog ownership. Extended longitudinal designs will be necessary to determine whether such short-term effects truly mediate lowered long-term risk.

All-cause and cause-specific mortality risks in individuals with diabetes living alone: A large-scale population-based cohort study

AIMS

The rise in one-person households is a global trend. We aimed to investigate mortality risk in individuals with diabetes living alone (IDLA) using a large-scale population-based database.

METHODS

A total of 2,447,557 adults with type 2 diabetes were identified from the Korean National Health Information Database. One-person households were defined based on the number of registered family members. The risks of all-cause and cause-specific mortalities were estimated using a multivariable Cox proportional hazards regression model.

RESULTS

During a median follow-up period of 6.0 years, 191,084 deaths (7.8 %) occurred. IDLA had a higher risk of mortality compared to those not living alone after adjusting for potential confounders (HR 1.20, 95 % CI: 1.18-1.22). This association was more prominent in younger individuals, men, and those with low income, and it was dependent on the duration of living alone. The risks of cause-specific mortality were all significantly higher in the IDLA group compared with the non-IDLA group. Adherence to favorable lifestyle behaviors was associated with a significant reduction in all-cause mortality, particularly in IDLA.

CONCLUSIONS

The elevated risk of mortality in IDLA highlights the need for tailored medical interventions and social assistance, particularly for those with unhealthy lifestyles or low income.

The impact of social partners: investigating mixed-strain housing effects on aging in female mice

Aging is a multifaceted process characterized by the gradual decline of physiological functions and can be modulated by various internal and external factors. While social interactions have been shown to affect behaviors and physiology in different species, the impact of social partners on aging-related phenotypes and lifespan in mice remains understudied. To address this question, we investigated various aging-related traits and lifespan in two mouse strains, C57BL/6J and BALB/c, under two different housing conditions: mixed-strain and same-strain housing. Analyses using a Generalized Linear Model revealed significant differences between the two strains in several phenotypes, including metabolic, anxiety-like, and electrocardiographic traits. However, surprisingly, housing conditions did not significantly affect most of the examined parameters, including overall lifespan. Only 3 out of 25 traits-body weight change in a metabolic cage, running wheel activity, and survival days of a quartiles of mice with middle lifespans-were influenced by housing conditions in a strain-dependent manner. Together, our study suggested a minimal influence of co-housing with social partners from different genetic backgrounds on aging-related phenotypes. This result demonstrates the feasibility of mixed housing for mouse husbandry and, more importantly, provides valuable insights for future research on the social influences on the aging process in mice.

Prevalence and burden of loneliness in COPD: A systematic review and meta-analysis

BACKGROUND

Loneliness poses significant public health concerns on a global scale. Being alone and lacking social connections have been proven to impact prognosis and response to treatment in different diseases, including COPD. Yet, the prevalence and burden of loneliness on COPD outcomes remain unclear.

METHODS

Various relevant databases were systematically searched in March 2024. The quality of the studies included was assessed using a modified Newcastle-Ottawa Scale. The random effect model was used to compute the pooled prevalence and associated 95 % confidence intervals (95%CI) of loneliness and living alone in COPD patients.

RESULTS

After reviewing 256 studies, 11 studies, including 4644 COPD patients, met the inclusion criteria and were included in the systematic review. Of the included studies, 5/11 (45.5%) reported the prevalence of loneliness or lone living among COPD patients and were included in the meta-analysis. The prevalence of loneliness and lone living among COPD patients was 32% (95% CI = 16%-48%) and 29% (95% CI = 16%-41%), respectively. The Three-item UCLA loneliness scale was the most often used loneliness assessment tool (5/11, 45.5%). Loneliness and lone living were associated with poor outcomes, including emergency department visits, readmissions, depression, and reduced pulmonary rehabilitation response.

CONCLUSION

Despite one-third of COPD patients experiencing loneliness, researchers have not consistently documented its impact on COPD outcomes. More studies are needed to assess the impact of loneliness on COPD and how to mitigate the negative effects on patients' outcomes.

Chronic stress in adulthood results in microvascular dysfunction and subsequent depressive-like behavior

Depression is a prevalent mental disorder characterized by unknown pathogenesis and challenging treatment. Recent meta-analyses reveal an association between cardiovascular risk factors and an elevated risk of depression. Despite this, the precise role of vascular injury in depression development remains unclear. In this investigation, we assess vascular system function in three established animal models of depression- chronic unpredictable mild stress (CUMS), chronic social defeat stress (CSDS) and maternal separation (MS)-utilizing ultrasonography and laser Doppler measurement. All three model animals exhibit anhedonia and despair-like behavior. However, significant microvascular dysfunction (not macrovascular) is observed in animals subjected to CUMS and CSDS models, while such dysfunction is absent in the MS model. Statistical analysis further indicates that microcirculation dysfunction is not only associated with depression-like behavior but is also intricately involved in the development of depression in the CUMS and CSDS models. Furthermore, our study has proved for the first time that endothelial nitric oxide synthase-deficient (eNOS+/-) mice, which is a classic model of vascular endothelial injury, showed depression-like behavior which occurred two months later than microvascular dysfunction. Notably, the mitigation of microvascular dysfunction successfully reverses depression-like behavior in eNOS+/- mice by enhancing nitric oxide production. In conclusion, this study unveils the pivotal role of microvascular dysfunction in the onset of depression induced by chronic stress in adulthood and proposes that modulating microvascular function may serve as a potential intervention in the treatment of depression.

N-Pep-Zn Improves Cognitive Functions and Acute Stress Response Affected by Chronic Social Isolation in Aged Spontaneously Hypertensive Rats (SHRs)

BACKGROUND/OBJECTIVES

Aging and chronic stress are regarded as the most important risk factors of cognitive decline. Aged spontaneously hypertensive rats (SHRs) represent a suitable model of age-related vascular brain diseases. The aim of this study was to explore the effects of chronic isolation stress in aging SHRs on their cognitive functions and response to acute stress, as well as the influence of the chronic oral intake of N-Pep-Zn, the Zn derivative of N-PEP-12.

METHODS

Nine-month-old SHRs were subjected to social isolation for 3 months (SHRiso group), and one group received N-pep-Zn orally (SHRisoP, 1.5 mg/100 g BW). SHRs housed in groups served as the control (SHRsoc). The behavioral study included the following tests: sucrose preference, open field, elevated plus maze, three-chamber sociability and social novelty and spatial learning and memory in a Barnes maze. Levels of corticosterone, glucose and proinflammatory cytokines in blood plasma as well as salivary amylase activity were measured. Restraint (60 min) was used to test acute stress response.

RESULTS

Isolation negatively affected the SHRs learning and memory in the Barnes maze, while the treatment of isolated rats with N-Pep-Zn improved their long-term memory and working memory impairments, making the SHRisoP comparable to the SHRsoc group. Acute stress induced a decrease in the relative thymus weight in the SHRiso group (but not SHRsoc), whereas treatment with N-Pep-Zn prevented thymus involution. N-pep-Zn mitigated the increment in blood cortisol and glucose levels induced by acute stress.

CONCLUSIONS

N-pep-Zn enhanced the adaptive capabilities towards chronic (isolation) and acute (immobilization) stress in aged SHRs and prevented cognitive disturbances induced by chronic isolation, probably affecting the hypothalamo-pituitary-adrenal, sympathetic, and immune systems.

Korean Red Ginseng and Rb1 restore altered social interaction, gene expressions in the medial prefrontal cortex, and gut metabolites under post-weaning social isolation in mice

Background

Post-weaning social isolation (SI) reduces sociability, gene expressions including myelin genes in the medial prefrontal cortex (mPFC), and alters microbiome compositions in rodent models. Korean Red Ginseng (KRG) and its major ginsenoside Rb1 have been reported to affect myelin formation and gut metabolites. However, their effects under post-weaning SI have not been investigated. This study investigated the effects of KRG and Rb1 on sociability, gene expressions in the mPFC, and gut metabolites under post-weaning SI.

Methods

C57BL/6J mice were administered with water or KRG (150, 400 mg/kg) or Rb1 (0.1 mg/kg) under SI or regular environment (RE) for 2 weeks during the post-weaning period (P21-P35). After this period, mice underwent a sociability test, and then brains and ceca were collected for qPCR/immunohistochemistry and non-targeted metabolomics, respectively.

Results

SI reduced sociability compared to RE; however, KRG (400 mg/kg) and Rb1 significantly restored sociability under SI. In the mPFC, expressions of genes related to myelin, neurotransmitter, and oxidative stress were significantly reduced in mice under SI compared to RE conditions. Under SI, KRG and Rb1 recovered the altered expressions of several genes in the mPFC. In gut metabolomics, 313 metabolites were identified as significant among 3027 detected metabolites. Among the significantly changed metabolites in SI, some were recovered by KRG or Rb1, including metabolites related to stress axis, inflammation, and DNA damage.

Conclusion

Altered sociability, gene expression levels in the mPFC, and gut metabolites induced by two weeks of post-weaning SI were at least partially recovered by KRG and Rb1.

Evaluation of Changes in Social Isolation and Loneliness with Incident Cardiovascular Events and Mortality

BACKGROUND

It remains unknown how the patterns of change of social isolation and loneliness are associated with the onset of cardiovascular disease (CVD) and mortality. We aimed to investigate the longitudinal association of changes in social isolation and loneliness with incident CVD, all-cause mortality, CVD mortality and subsequent cardiac function.

METHODS

This prospective cohort study included 18,258 participants aged 38-73 years who participated in visit 0 (2006-2010) and visit 1 (2012-2013) using UK Biobank (mean age 57.1, standard deviation [SD] 7.4; 48.7% males). Social isolation or loneliness was categorized into four patterns: never, transient, incident, and persistent. Incident CVD, all-cause and CVD mortality were ascertained through linkage data. Cardiac function was assessed by cardiovascular magnetic resonance imaging in a subsample (N = 5188; visit 2, since 2014).

RESULTS

Over a median follow-up of 8.3 (interquartile range [IQR] 8.1-8.6) years, compared with never social isolation, persistent social isolation was associated with the higher risk of incident CVD (hazard ratio [HR] 1.17, 95% confidence interval [CI] 1.03-1.33), all-cause (1.42, 1.12-1.81) and CVD (1.53, 1.05-2.23) mortality. Likewise, persistent loneliness was strongly associated with the greater risk of incident CVD (1.13, 1.00-1.27), all-cause (1.28, 1.02-1.61) and CVD mortality (1.52, 1.06-2.18).

CONCLUSIONS

Persistent social isolation and loneliness posed a substantially higher risk for incident CVD, all-cause and CVD mortality, and cardiac dysfunction than other patterns. Persistent social isolation and loneliness, along with an increasing cumulative score, are associated with lower cardiac function.

Extension of the theory of adherence to treatment in patients with coronary heart disease

Background

Increased knowledge of the concept of adherence is needed for development patient-centered care, nursing interventions, and guidelines for patients with coronary heart disease (CHD). The aim of this study was to test and extend the Theory of Adherence to Treatment regarding informational support in patients with CHD.

Methods

The study utilized an explanatory and descriptive survey. The study was conducted in 2013 and involved 416 patients in five hospitals in Finland. The Adherence of Patients with Chronic Disease instrument and the Social Support for People with CHD instrument were used. The model was tested using structural equation modeling (SEM).

Results

SEM confirmed direct associations between motivation (β = 0.49, p < 0.001) and results of care (β = 0.29, p < 0.01), and indirect associations between sense of normality, fear of complications, support from nurses and next of kin, and informational support to adherence to a healthy lifestyle and medication. Informational support included information and advice on CHD risk factors, physical exercise, chest pain, medication, continuum of care, and rehabilitation. Indirect standardized path coefficients varied between 0.14 and 0.45. The model explained 45% of adherence to a healthy lifestyle and medication.

Conclusion

The results of this study showed that informational support is a justified extension to the original Theory of Adherence to Treatment in Patients with CHD. Informational support seems to offer a new perspective that can be used to develop patient-centered nursing interventions and thus support adherence to treatment by patients with a lifelong disease such as CHD.

The impact of the COVID-19 pandemic on the socioeconomic gradient of hypertension

The COVID-19 pandemic has brought into sharp focus the impact of socioeconomic factors on hypertension outcomes. This review examines the implications of the pandemic on the socioeconomic gradient of hypertension and explores the physiological and pathophysiological processes underlying this relationship. Changes in socioeconomic factors have disproportionately affected individuals with lower socioeconomic status, leading to adverse hypertension outcomes. The pandemic-related stressors, coupled with social isolation and disrupted daily routines, have contributed to elevated stress levels among individuals, particularly those with lower socioeconomic status. Equitable access to healthcare, enhancing health literacy and patient empowerment, and addressing social determinants of health are essential components of hypertension management strategies. By recognizing the specific challenges faced by individuals with lower socioeconomic status and implementing targeted interventions, public health efforts can help reduce the socioeconomic gradient of hypertension.

Psycho-social dimensions of cardiovascular risk: exploring the impact of social isolation and loneliness in middle-aged and older adults

BACKGROUND

Cardiovascular disease (CVD) is a major health concern for middle-aged and older adults, with lifestyle and metabolic risk factors well-studied. However, the role of psychosocial factors in CVD remains underexplored.

OBJECTIVE

This study aims to delve into the connection between psychosocial factors and the occurrence of CVD.

METHODS

We utilized data from the UK Biobank, a large-scale study covering adults aged 38 to 73 recruited from various centers across the UK between 2006 and 2010. We employed Cox proportional hazards models to analyze the relationship between social isolation, loneliness, and incident CVD. CVD diagnoses were confirmed through hospital records and death-register data. Additionally, we conducted mediation analyses to assess the impact of low-grade inflammation.

RESULTS

The study encompassed 427,942 participants free from CVD, 55.8% of whom are women. High levels of social isolation and loneliness were linked to a higher risk of CVD (HRs 1.11, 95% CI 1.06-1.16; HRs 1.17, 95% CI 1.11-1.23). Depression also emerged as a predictor of CVD onset (HRs 1.25, 95% CI 1.19-1.31), with each psychosocial factor independently contributing to increased CVD risk. Mediation analyses pinpointed inflammation as a crucial mediator, especially for loneliness (indirect effect proportion: 4.7%).

CONCLUSIONS

This study underscores the significance of psychosocial factors in relation to CVD. Integrating assessments for social isolation, loneliness, and depression into routine healthcare could potentially aid in CVD prevention among middle-aged and elderly individuals. This study underscores the significance of psychosocial factors in relation to CVD, emphasizing the association between social isolation or loneliness and the heightened risk of CVD.

Effects of Electroencephalogram Neurofeedback Intervention on Blood C-Reactive Protein Levels in Astronauts Attending 2-Week Long Analog Moon Mission

The human organism is affected by multiple stressors every single day, especially during extremely demanding activities. It needs a method to regulate itself better. One of the stressors that is affecting humans is social isolation. The state of prolonged isolation happens during space missions. In this study, 40 analog astronauts attended a two-week-long mission. The experimental group had EEG neurofeedback training intervention performed on a daily basis, while the control group remained isolated without neurofeedback. The results let us take this non-invasive intervention under consideration, while debating the methods to lower the physiological stress reaction in humans that are exposed to extremely hard circumstances. Although not statistically significant, the trends observed give us direction towards other research to confirm EEG neurofeedback as a method to lower cell stress response levels.

Community Health Dialogue Implementation for the Solution of Loneliness in Rural Communities: Autoethnography

INTRODUCTION

Isolation and loneliness among older adults in rural communities pose significant risks to physical and mental health, leading to higher rates of morbidity and mortality. This study investigates the impact of continual rural health dialogues facilitated by family physicians on reducing loneliness and enhancing community health in Unnan City, Shimane Prefecture, Japan.

METHOD

Using a constructivist grounded theory approach, we conducted a qualitative study involving 165 participants over 65 from five rural communities between April 2022 and March 2024. Monthly health dialogues covered chronic diseases, exercise, and polypharmacy. Data were collected through ethnographic observations, focus group interviews, and field notes, with iterative coding and analysis to identify themes and concepts.

RESULTS

Three primary themes emerged: the existence of loneliness and its impact on health, motivation to address loneliness through a sense of security, and recognition of the importance of community engagement in reducing loneliness. Participants reported increased health awareness, enhanced community interaction, and recognition of loneliness's prevalence and health impacts. Regular dialogues fostered trust with healthcare professionals, encouraged proactive health management, and facilitated supportive community connections. These interactions significantly reduced feelings of loneliness and improved health outcomes.

CONCLUSION

Continual rural health dialogues effectively mitigate loneliness and enhance health outcomes in rural communities by fostering regular interactions and building supportive networks. These findings underscore the importance of community engagement and continuous relationships with healthcare professionals in addressing loneliness. Policymakers and healthcare providers should consider integrating such dialogues into rural health strategies to promote healthier, more connected communities. Future research should explore these interventions' long-term sustainability and broader applicability across diverse rural settings.

Unshared Minds, Decaying Worlds: Towards a Pathology of Chronic Loneliness

The moment when a person's actual relationships fall short of desired relationships is commonly identified as the etiological moment of chronic loneliness, which can lead to physical and psychological effects like depression, worse recovery from illness and increased mortality. But, this etiology fails to explain the nature and severe impact of loneliness. Here, we use philosophical analysis and neuroscience to show that human beings develop and maintain our world-picture (our sense of what is true, important, and good) through joint attention and action, motivated by friendship, in the Aristotelian sense of "other selves" who share a sense of the true and the good, and desire the good for each other as much as for themselves. The true etiological event of loneliness is the moment one's world-picture becomes unshared. The pathogenesis is a resultant decay of our world-picture, with brain and behavior changes following as sequelae.

A machine-learning approach to model risk and protective factors of vulnerability to depression

There are multiple risk and protective factors for depression. The association between these factors with vulnerability to depression is unclear. Such knowledge is an important insight into assessing risk for developing depression for precision interventions. Based on the behavioral data of 496 participants (all unmarried and not cohabiting, with a college education level or above), we applied machine-learning approaches to model risk and protective factors in estimating depression and its symptoms. Then, we employed Random Forest to identify important factors which were then used to differentiate participants who had high risk of depression from those who had low risk. Results revealed that risk and protective factors could significantly estimate depression and depressive symptoms. Feature selection revealed four key factors including three risk factors (brooding, perceived loneliness, and perceived stress) and one protective factor (resilience). The classification model built by the four factors achieved an ROC-AUC score of 75.50% to classify the high- and low-risk groups, which was comparable to the classification performance based on all risk and protective factors (ROC-AUC = 77.83%). Based on the selected four factors, we generated a mood vulnerability index useful for identifying people's risk for depression. Our findings provide potential clinical insights for developing quick screening tools for mood disorders and potential targets for intervention programs designed to improve depressive symptoms.

The role of loneliness in the association between sexual orientation and depressive symptoms among older adults: A prospective cohort study

BACKGROUND

This study aims to understand the mechanisms contributing to the elevated risk of depression among sexual minority older adults compared to heterosexuals. Specifically, the role of loneliness as a potential mediator is investigated to inform targeted interventions for preventing depression in sexual minority populations.

METHODS

Data from the English Longitudinal Study of Ageing, focusing on adults aged over 50, were analysed. Sexual orientation (sexual minority or heterosexual) and loneliness scores (UCLA scale) were assessed at wave six (2010-2011), while depressive symptoms (CESD) were assessed at wave seven (2013-14). Linear regression models and mediation analyses, using g-computation formula and adjusted for confounders, were conducted.

RESULTS

The sample included 6794 participants, with 478 (7.0 %) identifying as sexual minorities. After adjustments, sexual minorities scored higher on depressive symptoms at wave seven (mean difference): 0.23, 95 % CI 0.07 to 0.39) and loneliness at wave six (MD: 0.27, 95 % CI 0.08 to 0.46). Loneliness was positively associated with depressive symptoms (coefficient: 0.27, 95 % CI 0.26 to 0.29). In mediation analyses, loneliness explained 15 % of the association between sexual orientation and subsequent depressive symptoms.

LIMITATIONS

The dataset used sexual behaviour rather than desire and identity, potentially skewing representation of sexual minorities. Additionally, transgender older adults were not included due to limited gender diversity reported within the ELSA dataset.

CONCLUSIONS

Loneliness appears to be a significant modifiable mechanism contributing to the heightened risk of depressive symptoms in sexual minority older adults compared with their heterosexual counterparts.

Chronic loneliness and the risk of incident stroke in middle and late adulthood: a longitudinal cohort study of U.S. older adults

Background

Loneliness has been implicated as a stroke risk factor, yet studies have examined loneliness at only one time point. The association of loneliness changes and risk of incident stroke remains understudied. Our aim was to examine the association of loneliness with incident stroke, particularly the role of loneliness chronicity.

Methods

This prospective cohort study examined data from the Health and Retirement Study during 2006-2018. For analyses examining baseline loneliness only, we included U.S. adults aged 50 years or older and stroke-free at baseline and excluded individuals missing data on loneliness and those who experienced death at baseline. For analyses examining loneliness changes over two time points, we included those aged 50 years or older at baseline and stroke-free through the exposure measurement period. Individuals missing a loneliness scale measure or those who experienced death during the exposure measurement period were excluded. Loneliness was measured with the 3-item Revised UCLA Loneliness Scale. We constructed loneliness scores (range 3-9), dichotomized loneliness measures (high vs low using a >6 cutoff), and loneliness patterns across two time points (consistently low, remitting, recent onset, consistently high). Cox regression models estimated associations of baseline loneliness (N = 12,161) with incident stroke over a 10-12-year period, and loneliness change patterns (N = 8936) with incident stroke over a subsequent 6-8-year period, adjusting for demographics, health behaviors and health conditions.

Findings

Higher loneliness scores at baseline were associated with incident stroke for continuous (hazard ratio [HR]: 1.05, 95% confidence interval [CI]: 1.01-1.08) and dichotomized (HR: 1.25, 95% CI: 1.06-1.47) loneliness measures, and persisted after adjustment for social isolation but not depressive symptoms. Only individuals with a consistently high loneliness pattern over time (vs consistently low) had significantly higher incident stroke risk (HR: 1.56, 95% CI: 1.11-2.18) after adjusting for depressive symptoms and social isolation.

Interpretation

Chronic loneliness was associated with higher stroke risk independent of depressive symptoms or social isolation. Addressing loneliness may have an important role in stroke prevention, and repeated assessments of loneliness over time may help identify those particularly at risk.

Funding

National Institute on Aging (NIA U01AG009740).

Social Isolation Changes and Long-Term Outcomes Among Older Adults

Importance

While the association between cross-sectional measures of social isolation and adverse health outcomes is well established, less is known about the association between changes in social isolation and health outcomes.

Objective

To assess changes of social isolation and mortality, physical function, cognitive function, cardiovascular disease (CVD), and stroke.

Design, Setting, and Participants

In a cohort design, social isolation changes in 4 years and subsequent risk of mortality and other outcomes were assessed using the 13 649 eligible Health and Retirement Study (HRS) respondents from the 2006 to 2020 waves. Data were analyzed from October 11, 2023, to April 26, 2024.

Exposure

The main exposure was the change in social isolation measured by the Steptoe 5-item Social Isolation Index from the initial assessment to a second assessment conducted 4 years later. Participants were classified into decreased isolation, stable, or increased isolation groups, stratified by their baseline isolation status.

Main Outcomes and Measures

The primary outcomes were mortality, self-reported dependencies in activities of daily living, Alzheimer disease and Alzheimer disease-related dementia, CVD, and stroke. Dementia, CVD, and stroke were assessed using HRS-linked Medicare records. Incidence rates (IRs) of each group were estimated and a Cox proportional hazards regression model was used, with inverse-probability treatment weighting to adjust for confounders.

Results

Among 13 649 participants (mean [SD] age at baseline, 65.3 [9.5] years; 8011 [58.7%] women) isolated at baseline, those with increased isolation had higher mortality (n = 693; IR = 68.19; 95% CI, 60.89-76.36 per 1000 person-years) than those who were stable (n = 1796; IR = 44.02; 95% CI, 40.47-47.88 person-years) or had decreased isolation (n = 2067; IR = 37.77; 95% CI, 34.73-41.09 person-years) isolation. Increased isolation was associated with higher risks of mortality (adjusted hazard ratio [AHR], 1.29; 95% CI, 1.09-1.51), disability (AHR, 1.35; 95% CI, 1.09-1.67), and dementia (AHR, 1.40; 95% CI, 1.02-1.93) compared with stable isolation. Similar findings were observed among socially nonisolated participants at baseline.

Conclusions and Relevance

In this cohort study, increased isolation was associated with elevated risks of mortality, disability, and dementia, irrespective of baseline isolation status. These results underscore the importance of interventions targeting the prevention of increased isolation among older adults to mitigate its adverse effects on mortality, as well as physical and cognitive function decline.

Adaptation and Implementation of a Volunteer-Delivered, Telephone-Based, Social Support Program HOW-R-U? During the COVID-19 Pandemic: A Pragmatic Study

BACKGROUND AND OBJECTIVES

Public health concerns surrounding social isolation and loneliness heightened during the coronavirus disease 2019 (COVID-19) pandemic, as infection prevention measures led to increased feelings of loneliness and depression. Our objective was to evaluate the implementation of the HOW-R-U? program, during the pandemic (March 2020-December 2021). HOW-R-U? is a weekly volunteer-delivered telephone program designed to facilitate social connection and ease feelings of social isolation, loneliness, and depression in older people.

RESEARCH DESIGN AND METHODS

This pragmatic study used the Implementation Framework for Aged Care to adapt and implement HOW-R-U? in an Australian aged and community care organization and a tertiary health service in Melbourne. The evaluation involved analysis of program data, semistructured interviews, and surveys with program recipients, volunteers, and referrers. A process evaluation was conducted alongside an assessment of outcomes including pre- and post-symptoms of isolation, depression, and loneliness.

RESULTS

The implementation evaluation indicated that codesigned systems and processes effectively supported the ongoing implementation of HOW-R-U? with transition into business as usual across both organizations. Recipients reported that telephone calls had a positive impact on their lives, whereas volunteers reported enjoyment of supporting others. Several challenges were identified, namely in program reach and fidelity.

DISCUSSION AND IMPLICATIONS

HOW-R-U? was well regarded by all involved, and evaluation learnings have informed implementation into business as usual by both organizations.

The association between loneliness with health service use and quality of life among informal carers in Australia

OBJECTIVE

The demanding nature of caregiving and limited social support can lead to informal carers experiencing loneliness, which can impact their well-being and overall health service use (HSU). The study aims to examine the association between loneliness with HSU and Health state utility values among informal carers in Australia.

METHODS

Data were derived from three waves (2009, 2013, and 2017) of the nationally representative longitudinal Household Income and Labour Dynamics of Australia (HILDA) survey, focusing on adult informal carers. Outcome measures included visits to the General Practitioner, the number of hospital admissions, and the SF-6D score. Generalized Estimating Equations (GEE) analysis was conducted to explore the associations between loneliness and HSU, as well as loneliness and utility values (based on SF-6D) while adjusting for age, sex, education, marital status, income, and physical/mental health conditions.

RESULTS

After controlling for covariates, lonely carers reported lower utility values (IRR = 0.91, 95%CI [0.89, 0.93], p < 0.001) compared to non-lonely carers. Lonely carers reported a higher number of GP visits (IRR = 1.18, 95% CI [1.04, 1.36], p < 0.05) as well as a higher likelihood of visiting specialists (AOR = 1.31, p = 0.046) and hospital doctors (AOR = 1.42, p = 0.013) compared to the non-lonely carers.

CONCLUSIONS

The findings of this study highlight the relationship between loneliness on both healthcare utilization and carers' overall well-being. Addressing loneliness through targeted interventions and social support systems can help improve health outcomes and potentially reduce the overall healthcare costs among informal carers in Australia.