Loneliness is an aversive emotion occurring when a person feels their social relationships are deficient in some way. As a loneliness researcher and someone who, like many, has felt lonely at periods during their life, I have welcomed increasing public/political interest the area in the last few years.
For example, the UK has seen the creation of a Minister for Loneliness and a Loneliness Strategy (HM Government, 2018). While the creation of a minister whose remit is limited to a single emotion may seem unusual, research suggests that the focus is warranted; being lonely is associated with higher risk of physical health issues, like cardiac disease and immune deficiency and mental health issues, such as anxiety and depression (Cacioppo et al 2002). Furthermore, loneliness is common: in the UK over 9 million (or almost 1 in 5 people) say they are always or often lonely (British Red Cross and Co-Op, 2016). The recent global spread of self-isolation associated with COVID-19 has put an even stronger public focus in this area, hastening a need to better understand the risks of loneliness to formulate appropriate mental health responses.
In the paper that forms the focus of this blog, McClelland et al. (2020) explore the relationship between loneliness and suicide ideation and/or behaviour (SIB). Whilst previous systematic reviews have identified a link between the two (Calati et al, 2019; Mushtaq et al 2014), none have included a rigorous meta-analysis like this new review.
The paper has three aims:
- To explore whether loneliness was a significant predictor of later suicide ideation and/or behaviour (SIB)
- To identify if the loneliness – SIB relationship varied as a function of socio-demographics and/or geographic location
- To determine whether depression acts as a mediator.
Research suggests there may be a link between loneliness and later suicidal ideation and/or behaviour (SIB), but until now rigorous reviews have been lacking.
Methods
This study is a systematic review of 947 original empirical papers, of which 22 met the inclusion criteria.
Suicide ideation and loneliness were measured across studies using self-report standardised and non-standardised measures. Suicidal behaviour was measured broadly, mostly using self-report measures which combined self-harm/suicide attempts (i.e. asking about attempts to die by suicide) or separately (questions about suicide attempts or questions about self-harm), however one study used hospital records. No studies included death by suicide as an outcome measure.
Rigour was ensured through adherence to PRISMA guidelines and use of the Quality Assessment Tool for Systematic Observational studies (QATSO; Wong et al, 2008). Any uncertainty regarding inclusion/exclusion criteria was discussed between the authors and an inter-rater check was conducted. The authors first undertook a narrative review of included studies and then a meta analysis of a suitable subsample of the studies.
Results
Relationship between loneliness and suicide ideation and/or behaviour (SIB)
Most of the studies included in the review (14 of 22) suggested that loneliness was a significant predictor of later SIB. The authors’ meta-analysis including 17 of the studies confirmed that loneliness was a significant predictor of overall later suicide ideation and/or behaviour (SIB).
Based on a meta-analysis of a subsample of eligible studies, the authors found that loneliness appeared to have a stronger effect on suicidal behaviour than it did on suicidal ideation. The author’s narrative review found that each type of SIB varied in its relationship to loneliness. Suicide ideation was significantly associated with suicide ideation in majority (12 of 20) of studies. Within studies examining suicidal behaviours, there was evidence of a stronger relationship between loneliness and self-harm (3 of 7 studies) than there was between loneliness and suicide attempts (1 of 6 studies). There was evidence that the relationship between self-harm and loneliness was strongest when the self-harm had no suicidal intent or was not considered a suicide attempt.
The authors found several factors impacted the loneliness-SIB relationship:
- Loneliness tended to be more highly associated with SIB in the medium to longer term (between one month to five years post-baseline) rather than in short-term settings
- Studies that had a higher sample size (i.e. ≥ 186 participants) tended to be more likely to show a significant loneliness-SIB association
- Studies that showed significant associations between loneliness and SIB were most likely to be those that had primarily female participants in particular age groups (those between ages of 16-20 or over 58), suggesting there may be significant gender and age effects. However, the authors’ meta-analysis did not confirm that gender or age moderated the relationship between loneliness and SIB.
Role of depression
Mediation model analyses showed a significant indirect effect from loneliness to suicide ideation and/or behaviour (SIB) via depression.
Loneliness appears to predict future suicidal ideation and/or behaviour (SIB).
Conclusions
The authors concluded that loneliness appears to predict future suicide ideation and/or behaviour (SIB). There was some evidence that this effect was strongest in specific groups, including those aged between 16-20 or over 58 years at baseline and in samples that were predominantly female, but these effects were not confirmed when the authors tested them using meta-analysis techniques. There was also evidence that the effect of loneliness on SIB was strongest within the medium term (up to 5 years). Depression was found to mediate the relationship between loneliness and SIB, but more research is needed to understand the mechanisms of this relationship.
Depression was identified as a mediator between loneliness and SIB, meaning that loneliness can lead to depression, which in turn can lead to suicidal ideation and/or behaviours.
Strengths and limitations
A clear strength of this paper was its rigorous methodology. This was evident through the use of meta-analysis of eligible studies and stringent inclusion criteria in the analysis. For example, studies were only included if i) SIB was measured at a later time-point to baseline loneliness and cross-sectional associations were excluded, and ii) if they explicitly measured loneliness, excluding studies inferring loneliness through indirect measures like ‘living status’.
The paper self-identified several limitations. The fact that the meta-analysis did not find significant gender and age moderation effects, despite these being apparent in the narrative review may be reflective of the heterogeneity in the studies in the review, including an under-representation of male participants and a lack of studies looking at participants between the age of 24 and 55. Criteria excluding studies published in non-English languages constrained the authors’ ability to compare between non-English and often non-Western cultures, despite research finding that loneliness could differ between individualistic or collectivistic cultures (Lykes and Kemmelmeier, 2014). Limitations around how gender was measured in studies limited the capacity of the authors to make inferences beyond the gender binary. Also, because few of the studies were deemed to be generalisable to a general population and many had heterogeneous samples and diverse methodology, the authors noted that any generalisations should be made with caution.
This new systematic review included studies from Western cultures, meaning that few inferences can be made about how the relationship between loneliness and suicidal ideation and/or behaviours may differ across cultures.
Implications for practice
This research has several implications for how we think about the causes of suicide. For example, the Interpersonal Theory of Suicide (Van Orden et al, 2010) identifies thwarted belongingness, a concept very similar to loneliness, as a significant precursor of suicidal behaviours. Similarly, the Integrated Motivational-Volitional model of suicide (O’Connor and Kirtley, 2018) frames loneliness as a motivating factor in developing a sense of entrapment, which is a primary precipitant of suicidal intentions/ideation.
Mental health practitioners may be interested in learning about the potentially higher risk of SIB amongst lonely clients in specific age groups. The authors reasoned that younger adults and older adults may be lonelier because these are ages where substantial life events and changes in social status occur, such as transitioning from school into university/work or from work into retirement.
Social isolation and thwarted belongingness seem to motivate engagement in suicidal ideation and/or behaviours.
Statement of interests
None.
Links
Primary paper
McClelland, H., Evans, J. J., Nowland, R., Ferguson, E., & O’Connor, R. C. (2020). Loneliness as a predictor of suicidal ideation and behaviour: a systematic review and meta-analysis of prospective studies. Journal of Affective Disorders, 274, 880-896.
Other references
British Red Cross and Co-op. (2016). Trapped in a bubble: An investigation into triggers for loneliness in the UK. Retrieved from UK: https://www.co-operative.coop/campaigning/loneliness
Cacioppo, J. T., Hawkley, L. C., Crawford, L. E., Ernst, J. M., Burleson, M. H., Kowalewski, R. B., . . . Berntson, G. G. (2002). Loneliness and health: Potential mechanisms. Psychosomatic Medicine, 64(3), 407-417.
Calati, R., Ferrari, C., Brittner, M., Oasi, O., Olié, E., Carvalho, A. F., & Courtet, P. (2019). Suicidal thoughts and behaviors and social isolation: A narrative review of the literature. Journal of Affective Disorders, 245, 653-667.
HM Government (2018). A connected society: A Strategy for tackling loneliness – laying the foundations for change. London, UK: HM Government
Lykes, V. A., & Kemmelmeier, M. (2014). What Predicts Loneliness? Cultural Difference Between Individualistic and Collectivistic Societies in Europe. Journal of Cross-Cultural Psychology, 45(3), 468-490.
Mushtaq, R. (2014). Relationship Between Loneliness, Psychiatric Disorders and Physical Health ? A Review on the Psychological Aspects of Loneliness. JOURNAL OF CLINICAL AND DIAGNOSTIC RESEARCH.
O’Connor, R. C., & Kirtley, O. J. (2018). The integrated motivational-volitional model of suicidal behaviour.Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 373(1754).
Van Orden, K. A., Witte, T. K., Cukrowicz, K. C., Braithwaite, S. R., Selby, E. A., & Joiner, T. E., Jr. (2010). The interpersonal theory of suicide. Psychological review, 117(2), 575-600.
Wong, W. C., Cheung, C. S., & Hart, G. J. (2008). Development of a quality assessment tool for systematic reviews of observational studies (QATSO) of HIV prevalence in men having sex with men and associated risk behaviours. Emerging Themes in Epidemiology, 5(1), 23.
Photo credits
- Photo by Sasha Freemind on Unsplash
- Photo by Matthew Henry on Unsplash
- Photo by Papaioannou Kostas on Unsplash
HI my name is Norma, I once was a depressed person, nothing was going right in my life, I felt unloved by others, I wanted to crawl in a hole and die. Loneliness comes with depression. I no that for a fact. I was also lonely for a very long time, even when I was around others. I wanted to fit in with others, but that never happened. I wanted to be liked by others, that again never happened. I came from a family who my parents (well at least my mom) never meant it when she told us that she loved us. A person can tell it in their voice and by their actions, actions speak louder than words. I even had my mother to tell me that she wished she never had any kids, that she was supposed to have married a rich man, but instead married my dad. All through the time I was growing up , she never really loved us. So I know what it is not to be loved by anyone. I was depressed all my life, I was lonely as well. I over came this by reading my Bible, and found out that there is one person who loves me, and it took a long time before I realized it . I found out that God loves me. I have been on medication for my depression for a long time, and it works. Reading the Bible helps a person to be strong in everything, yes I have problems at times with loneliness, but I just open my Bible and read Gods love letter to us.
Being lonely is not fun, it only makes depression set in. I said this to say, depression comes with loneliness, we are humans, we need some affection from others, we were never meant to be alone. Oh one other thing, many years ago I was in an accident, my mind got confused of everything I was doing, my doctor would not send me my medication, I was coming down off of it, it was the worse downer I had ever been on. One day I was alone, I almost took my own life, I had called for help but the people did not really act like they cared about my situation. I wanted to end my life, I don’t no why, I guess cause I was depressed, lonely, confused about what was going on in my life, but God helped me through that situation. It took 3 months or so to come down off this sleeping medicine and it was the worse time of my life. My doctor gave me something to counter act the sleeping medicine and it finally made me get on the right track. I also fired my doctor, and got another one, which later on I found out she was not as good as I thought she was. Being depressed brings on loneliness, There are many lonely people in this world, and many think about taking their own life, not only at my age, but I am talking about the younger adults, there is no way anyone can reach the people who want to take their life, I find this so sad, People needs others to feel comfort with, but that is another subject. Not everyone will ask for help, People don’t trust doctors.
I am a single male in my mid 60s who has been alone since moving out of the family home at the age of 14. During those 14 years, I knew that I had depression, but back then it was never talked about. I also had learning difficulties and was a loner. This continues even today, because I keep to myself and the depression, loneliness, and poor self esteem that I have has followed me all of my life. Yes, loneliness hurts, but to receive continual rejection is much more painful. I like many others out there I expect pray that we may end this hurt and pain sooner rather than later.