by Selina Allerstorfer -

#04 Impact of Loneliness on Health

Social connection and satisfying relationships are fundamental for development, reproduction and survival. The impact of social influences on health and well-being has been extensively investigated through diverse scientific methodologies like epidemiological studies, network analyses, clinical trials and controlled experiments. Consistent evidence indicates that loneliness and social isolation negatively affect mental, physical, and cognitive health, with the most compelling findings linking these factors to an increased risk of premature mortality. 1 Several meta-analyses find that the risk of all-cause mortality is increased by 26 %. Moreover, these findings were consistent across various factors, including age, gender, cause of death, country of origin, and baseline health status 2 

Existing research makes a difference in all-cause mortality and cause-specific mortality, particularly when talking about cardiovascular diseases or strokes. All-cause mortality refers to the collective risk of death from all conditions associated with loneliness, while cause-specific mortality focuses on the risk of dying from a specific condition closely linked to loneliness or social isolation. 

Research has explored the individual and combined effects of loneliness and social isolation on mortality risk. While both factors independently correlate with higher mortality, studies suggest that social isolation is the stronger predictor when both are analyzed together. For example, some studies show that only social isolation remained significant after controlling for demographic, socio-economic, and health factors. 3 Beller and Wagner observed that loneliness and social isolation interact synergistically: greater social isolation amplifies the impact of loneliness on mortality, while higher loneliness intensifies the effect of social isolation. 4

The impact of social relationships on mortality risk can be compared to other well-established lifestyle risk factors like physical activity, alcohol consumption, smoking cigarettes, air pollution or obesity. 5

Comparison of Decreased Mortality across social connection and leading health indicators 3

Physical health

In addition to their association with increased mortality risk, social isolation and loneliness are linked to various health issues, including cardiovascular diseases, stroke, functional decline, and, to some extent, reduced immune function and diabetes. 3

Cardiovascular diseases
Cardiovascular diseases include diseases affecting the heart or blood vessels like heart attacks or strokes. A meta-analysis which is based on 23 different studies shows that loneliness and social isolation are linked to a 29 % higher risk of coronary heart disease and a 32 % higher risk of stroke. These associations were observed in both genders and remained significant regardless of traditional heart disease risk factors. Studies show that loneliness is linked to an increased risk of high blood pressure, particularly among middle-aged and older adults, and inflammatory reactivity. 3

Functional and motor decline
Loneliness is linked to increased functional and motor decline, including greater difficulty with activities of daily living and reduced muscle strength, mobility, and motor performance. 6 It remains unclear whether loneliness contributes to functional decline directly or indirectly through processes like cardiovascular diseases or inflammation. 7 

Diabetes and cholesterol
Few studies have linked loneliness to developing diabetes for men. A cross-sectional study in Switzerland shows that lonely people have a 40 % higher chance of developing diabetes and 31 % higher chance to have higher cholesterol levels. 8

Cognitive Health

Cognitive function encompasses a range of mental processes that enable an individual to acquire knowledge, reason, and carry out plans. These processes include perception, memory, learning, attention, decision-making, and language skills. 9

Cognitive decline
Several studies have explored the relationship between loneliness and/or social isolation, and cognitive decline, especially in older adults. Even though some studies show a link between loneliness and cognitive decline, they cannot agree on what part of the cognitive function is affected. 3

Alzheimer’s and Dementia
Most evidence suggests a correlation between loneliness and dementia, comparable to the other dementia risk factors like physical activity, low education and late-life-depression. 10 While a study from 2018 found no association between loneliness and dementia, there are other studies showing that there is a link between loneliness and developing dementia. To address the potential problem of reversed causality – where early-stage dementia leads to difficulties engaging in social interactions and therefore people feeling lonely – the study doesn’t include people in those early stages. 3

Mental health

A wide range of literature shows a significant relationship between loneliness and mental health issues like depression and anxiety as well as suicide and suicidal ideations. 3

Depression and Anxiety
Lonely individuals tend to experience more depressive symptoms and report being less happy, less satisfied, and more pessimistic. Additionally, loneliness and depression share common features, such as feelings of helplessness and emotional pain. 11 Another study also shows an association between poor social connection and social anxiety in both adolescents and adults. 1

Suicide and Suicidal Ideation
Studies indicate a connection between loneliness and suicide. A study of individuals who have attempted suicide found that loneliness is frequently cited as a contributing factor. 12

Taking loneliness seriously

Research shows that loneliness affects health, but the relationship is also bidirectional – some health conditions such as poor physical health, disabilities, or hearing loss, can also increase the likelihood of loneliness. The reported evidence highlights that loneliness should be taken more seriously as a risk factor for various health problems. 3

Sources

[1] J. Holt-Lunstad und Department of Psychology, Brigham Young University, Provo, Utah, USA, „Social Connection as a Public Health Issue: The Evidence and a Systemic Framework for Prioritizing the “Social” in Social Determinants of Health“, 2022. [Online]. Verfügbar unter: https://doi.org/10.1146/annurev-publhealth-052020-110732

[2] J. Holt-Lunstad, T. B. Smith, M. Baker, T. Harris, and D. Stephenson, “Loneliness and social isolation as risk factors for mortality: A meta-analytic review,” *Perspect. Psychol. Sci.*, vol. 10, no. 2, pp. 227–237, Mar. 2015, doi: 10.1177/1745691614568352. PMID: 25910392.

[3] J. Baarck, M. Kovacic und Joint Research Centre (JRC), „The Relationship between Loneliness and Health“, Publications Office of the European Union, literature review, 2022. doi: 10.2760/90915.

[4] J. Beller and A. Wagner, “Loneliness, social isolation, their synergistic interaction, and mortality,” Health Psychol., vol. 37, no. 9, pp. 808–813, Sep. 2018, doi: 10.1037/hea0000605. PMID: 30138019.

[5] J. Holt-Lunstad, T. F. Robles und D. A. Sbarra, „Advancing social connection as a public health priority in the United States.“, American Psychologist, Bd. 72, Nr. 6, S. 517–530, Sep. 2017, doi: 10.1037/amp0000103.

[6] K. Beaton and K. Grimmer, “Tools that assess functional decline: systematic literature review update,” Clin. Interv. Aging, vol. 8, pp. 485–494, 2013. Available at: https://doi.org/10.2147/CIA.S42528.

[7] A. S. Buchman et al., “Loneliness and the rate of motor decline in old age: the Rush Memory and Aging Project, a community-based cohort study,” BMC Geriatr., vol. 10, no. 1, p. 77, 2010. Available at: https://doi.org/10.1186/1471-2318-10-77. 

[8] R. A. Richard, S. Rohrmann, C. L. Vandeleur, M. Schmid, J. Barth, and M. Eichholzer, “Loneliness is adversely associated with physical and mental health and lifestyle factors: Results from a Swiss national survey,” PLoS One, vol. 12, no. 7, p. e0181442, Jul. 2017, doi: 10.1371/journal.pone.0181442. PMID: 28715478; PMCID: PMC5513556.

[9] K. Kiely, “Cognitive function,” in Encyclopedia of Quality of Life and Well-Being Research, A. C. Michalos, Ed., Dordrecht: Springer Netherlands, 2014, pp. 483–484. Available at: https://doi.org/10.1007/978-94-007-0753-5_2939.

[10] J. S. Kuiper, M. Zuidersma, R. C. Oude Voshaar, S. U. Zuidema, E. R. van den Heuvel, R. P. Stolk, and N. Smidt, “Social relationships and risk of dementia: A systematic review and meta-analysis of longitudinal cohort studies,” Ageing Res. Rev., vol. 22, pp. 39–57, Jul. 2015, doi: 10.1016/j.arr.2015.04.006. PMID: 25956016. 

[11] R. Mushtaq, S. Shoib, T. Shah und S. Mushtaq, „Relationship Between Loneliness, Psychiatric Disorders and Physical Health ? A Review on the Psychological Aspects of Loneliness“, JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH, Jan. 2014, doi: 10.7860/jcdr/2014/10077.4828.

[12] L. M. Heinrich, E. Gullone und School of Psychology, Psychiatry, and Psychological Medicine, Faculty of Medicine, Nursing, and Health Sciences, Monash University, VIC 3800, Australia, „The clinical significance of loneliness: A literature review“, 2006. [Online]. Verfügbar unter: https://doi.org/10.1016/j.cpr.2006.04.002

by victoria.bremer -

Loneliness – a quick overview

„The loneliness epidemic“ – a buzzword that has been coming up more and more in recent years. It seems to be an increasingly relevant topic, which is quite interesting and somewhat paradox, considering the parallel increase of innovative technology for creating connections between millions of people, no matter the time of day or location on the planet. However, something seems to be wrong. Reports show that around a third of the population of industrialized countries are affected by loneliness [1]. The group most affected by loneliness are young adults between 16 and 24 [5] and what is even more concerning – this number has been rising over the past few years [6]. The WHO has even declared loneliness a global public health concern in 2023 and launched and international commission to study the problem [2]. How can loneliness be such a prominent topic and increasing issue, when we are more connected than ever? This makes for an interesting research topic in which I will be asking the question of how interaction design can combat loneliness.

First of all, to better understand the topic of loneliness, the term has to be defined and differentiated from similar ones such as aloneness, solitude and social isolation, as these mean slightly different things. Aloneness and social isolation describe qualitative, objective measures in which an individual has no one around them. More subjective measures include solitude and loneliness. While solitude describes a feeling of voluntary aloneness, which is mostly a positive experience, loneliness is the opposite and describes a negative experience of the state of being alone [3]. There is no one definition of what loneliness is exactly, generally it is agreed that it can be described as the subjective discrepancy between an individual’s existing versus desired social relationships [1]. When looked at more closely, loneliness can be further categorized into three types. Social loneliness means the feeling of isolation from a social network or community. Simply put: the missing sense of belonging. Emotional loneliness describes the sense of lacking close, intimate, emotional connections. Finally, existential loneliness refers to a deeper inner feeling of being fundamentally alone in life. Further categorizations include transient, situational and chronic loneliness [3].

Since loneliness is for the most part a subjective feeling, it can be quite tricky to measure it for studies and observation. One of the most prominent attempts to measure loneliness is the UCLA loneliness scale which has bee revised several times and works like a relatively simple questionnaire [4].

Loneliness has a significant impact on mental and physical health. It can contribute, as well as cause depression. This vicious cycle has a high risk of increasing early mortality. With depression being the most common mental health issue, loneliness is a topic that should not be overlooked, since they are often intertwined [7]. Loneliness can also harm the body physically. Diabetes, autoimmune disorders, cardiovascular diseases, obesity, physiological aging, cancer, poor hearing and overall poor health have been found to be caused by loneliness [1,7]. Addressing loneliness could be an important step in the battle against the mental health crisis and improvement of physical wellbeing.
Besides mental and physical health loneliness can even impact the economy. Poorer work performance and lower educational attainment have been associated with loneliness and its accompanying symptoms. This is estimated to cost employers millions per year due to employee sickness, caring activity, productivity, and voluntary staff turnover [8].

It is clear that we need to better understand the loneliness epidemic in order to work on solutions that bring us together.

Sources

  1. C. Park et al., „The Effect of Loneliness on Distinct Health Outcomes: A Comprehensive Review and Meta-Analysis“, December 2020, doi: https://doi.org/10.1016/j.psychres.2020.113514
  2. „WHO Commission on Social Connection“, World Health Organization [Online], Available: https://www.who.int/groups/commission-on-social-connection, Accessed: December 2024
  3. „Definitions of lonely, isolated, alone, and solitude“, what works wellbeing, [Online], Available: https://whatworkswellbeing.org/resources/definitions-of-lonely-isolated-alone-and-solitude/, Accessed: December 2024
  4. D. Russell, UCL Loneliness Scale, Fetzer Institute, Available: https://fetzer.org/sites/default/files/images/stories/pdf/selfmeasures/Self_Measures_for_Loneliness_and_Interpersonal_Problems_UCLA_LONELINESS.pdf
  5. „16 to 24 year olds are the loneliest generation“, UKOnward, Available: https://www.ukonward.com/data/how-often-do-you-feel-lonely/, Accessed: January 2025
  6. „Community Life Survey 2023/24: Loneliness and support networks“, gov.uk, Available: https://www.gov.uk/government/statistics/community-life-survey-202324-annual-publication/community-life-survey-202324-loneliness-and-support-networks–2, December 2024
  7. R. Mushtaq, „Relationship Between Loneliness, Psychiatric Disorders and Physical Health ? A Review on the Psychological Aspects of Loneliness“, September 2014, doi: 10.7860/JCDR/2014/10077.4828
  8. Campaign to End Loneliness, “Facts and Statistics – Campaign to end loneliness,” Campaign to End Loneliness, May 10, 2024. https://www.campaigntoendloneliness.org/facts-and-statistics/