Understanding loneliness in the twenty-first century: an update on correlates, risk factors, and potential solutions.

PURPOSE: Loneliness is increasingly recognised as the next critical public health issue. A plausible reason for this concern may be related to emerging societal trends affecting the way we relate, communicate, and function in our social environment. In 2006, a prominent review of the clinical significance of loneliness was published. However, there has not been a comprehensive update on known and emerging risk factors and correlates of loneliness since then. Furthermore, there is no conceptual model that has been developed to better account for the complexity of loneliness and to inform the development of evidence-based solutions as we challenge the issues of the twenty-first century. METHODS: We reviewed the current literature to identify either known or emerging risk factors and correlates of loneliness since 2006. This includes new or known evidence on: (1) demography; (2) health, including physical health; mental health; cognitive health; brain, biology, and genetics; and (3) socio-environmental factors including digital communication and the workplace. RESULTS: We synthesized the literature according to a new proposed conceptual model of loneliness which showed the interplay between known and emerging correlates and risk factors from demography, health, to socio-environmental factors. In the conceptual model of loneliness, we illustrated how solutions can be delivered and tailored to an individual based on their life circumstances and preferences. CONCLUSION: We concluded by making specific recommendations in advancing our scientific understanding of loneliness. Our knowledge can only be deepened if we increase scientific rigour via accounting for confounding variables and using longitudinal, multi-disciplinary, and multiple methodologies in research. We also call for the rigorous evaluation of programs targeting loneliness.

Investigating the relationship between early cardiovascular disease markers and loneliness in young adults.

Loneliness is recognised as a risk factor for cardiovascular disease development. However, it is unclear whether loneliness itself or other closely related mental health symptoms, such as depression and social anxiety, are associated with the development of cardiovascular disease. In the present study, we examined the relationship between loneliness and several early cardiovascular disease markers in young adults, after controlling for depression and social anxiety. Sixty-six young adults (18-35 years old, Mage = 22.70; 75.8% females) completed psychological questionnaires and took part in several physiological tests assessing cardiovascular health (e.g., vascular function). Results revealed higher loneliness was significantly associated with shorter pulse transit time (ß = - 0.70, p = 0.002; shorter pulse transit time is a subclinical marker for arterial stiffness). Additionally, results show that while loneliness and depression were both related to vascular dysfunction in young adults, the underlining physiological mechanisms through which they affect vascular function may be different. Specifically, higher loneliness was associated with increased arterial stiffness, whereas depression was associated with increased endothelial dysfunction (ß = - 0.43, p = 0.04). Our findings indicate that presence of loneliness and depression in young adults may be accompanied by early indicators of poor cardiovascular health, such as arterial stiffness and endothelial dysfunction. Results from the study further support the link between loneliness and cardiovascular disease development.

Evaluating the impact of loneliness and social isolation on health literacy and health-related factors in young adults.

Objectives: In current study, we aim to extend previous research by investigating the unique impact of loneliness on health literacy and health-related factors of young adults, after controlling for social isolation, depressive symptomology, and social anxiety, as well as evaluate how social isolation and loneliness differ in their impact on health literacy, and health-related factors among young adults, after accounting for abovementioned concomitant variables. Methods: Using a cross-sectional study design, 521 young adults completed an online survey in 2020, where they self-reported their loneliness, social isolation, health-related factors, and health literacy data. Results: Increased loneliness was associated with decrease in several health literacy domains (e.g., poorer social support for health, lower appraisal of health information, among others) and increase in some health-related factors (e.g., higher perceived stress, higher negative affect), among young adults, even after controlling for social anxiety, depressive symptomology, and social isolation. Contrastingly, increase in social isolation was associated with changes in some health-related factors - more somatic health complaints, higher alcohol use, poorer cognitive and physical functioning, and lower scores for only one health literacy domain (i.e., social support for health) among young adults, after adjusting for the influence of social anxiety, depressive symptomology, and loneliness. Conclusion: Even after accounting for the influence of several co-occurring social and mental health symptoms, higher loneliness was associated poorer health literacy and health-related factors in young adults. We also found loneliness and social isolation may differ in the mechanisms through which they impact health literacy and health-related factors in young adults.

Stress and social isolation, and its relationship to cardiovascular risk in young adults with intellectual disability.

PURPOSE: Stress produces many physiological changes, some of which may contribute to the development of cardiovascular disease (CVD). Individuals with intellectual disability (ID) are exposed to multiple and stressful challenges everyday which may put them at increased cardiovascular risk. This current study aimed to establish whether adults with ID experience higher levels of subjective stress and encounter different stressors (including social isolation) than the general population, and whether there is a relationship between stress and cardiometabolic profile in this population. METHODS: Adults with ID (n = 35) aged 18-45 years completed the Subjective Stress Survey, and underwent a physiological assessment to measure blood pressure, metabolic profile and subclinical CVD risk factors, and were compared to a control group (n = 29). Multiple regression was used to investigate whether cardiometabolic parameters were predicative of SSS scores. RESULTS: Findings showed adults with ID have higher perceived stress levels (total score ID: 21.3 ± 11.4 vs control: 13.9 ± 9.0, p = 0.006), which is elicited by unique stressors, when compared to people without ID. Stress was strongly associated with increased social isolation (r = -0.38, p = 0.002) and with obesity in females with mild ID (r = 0.72). Regression showed that arterial stiffness was predictive of total SSS score (p = 0.038). CONCLUSIONS: Adults with ID aged 18-45 years report higher levels of perceived stress when compared to people without ID.Implications for RehabilitationReducing stress in this young population may prevent development of arterial stiffness, and consequently lower the risk of cardiometabolic morbidity and mortality.There are unique targets for stress management in young adults with intellectual disability, including supporting decision-making and improving self-efficacy.Improving community integration and reducing social isolation may decrease perceived stress in young adults with intellectual disability.

Loneliness and Cognitive Function in Older Adults Without Dementia: A Systematic Review and Meta-Analysis.

BACKGROUND: Loneliness has been highlighted as a risk factor for dementia. However, the nature of the relationship between loneliness and cognitive function prior to onset of dementia is unclear. OBJECTIVE: The aim of this systematic review and meta-analysis was to examine the relationship between loneliness and cognitive function in samples screened for dementia at study commencement. METHODS: Five electronic databases (PubMed, PsycNET, Web of Science, EBSCOhost, Scopus) were searched from inception to August 31, 2021. A narrative review and random-effects meta-analysis were conducted on studies meeting search criteria. PROSPERO registration number: CRD42020155539. RESULTS: The sixteen studies that met inclusion criteria involved 30,267 individuals, with mean age ranging from 63.0 to 84.9 years. Studies varied in dementia screening criteria, measurement of loneliness and cognitive function, and statistical modeling approach. The narrative review indicated that loneliness was associated with poorer global cognition, episodic memory, working memory, visuospatial function, processing speed, and semantic verbal fluency. Results of the meta-analysis indicated that loneliness was negatively associated with global cognitive function (overall r = -0.08; 95% CI = -0.14, -0.02; n = 6). Due to lack of sufficient data and heterogeneity between studies, we were unable to explore associations with other cognitive domains or longitudinal associations. CONCLUSION: Loneliness is associated with subtle impairment across multiple cognitive domains in older adults who were screened for dementia. Better characterization of this relationship will provide important information about how loneliness contributes to the clinical and pathological sequalae of AD and be informative for risk reduction and early detection strategies.

Impact of loneliness on health-related factors in Australia during the COVID-19 pandemic: A retrospective study.

COVID-19 pandemic and its associated social and physical distancing restrictions may have had a severe impact on health. In the present study, we investigate the changes in physical, social and mental health, as well as the health literacy of Australians subsequent to the onset of COVID-19 pandemic, and examine the influence of loneliness on these health-related factors. Using a retrospective cross-sectional study design, 607 Australian adults completed a self-report online survey which assessed their health-related factors before and after onset of the COVID-19 pandemic (data collected between June 2020 to November 2020). Australians reported statistically significant increase in a number of (poorer) health-related factors (e.g., weight gain, sleeping difficulties, poor somatic health, higher loneliness, more issues navigating the healthcare system) post onset of COVID-19 pandemic. Further, after adjusting for covariates, higher loneliness during pandemic predicted poorer health-related outcomes (e.g., more somatic health complaints, poorer quality of diet, poorer social support for health). The COVID-19 pandemic and its associated social and physical distancing restrictions may have contributed towards poorer health-related factors among Australian adults. Further, increased loneliness during the pandemic may have further worsened physical health and health literacy outcomes among Australians.