An overview of systematic reviews on the public health consequences of social isolation and loneliness

In the paper

“Eight reviews were undertaken in two or more countries, while the rest were carried out by teams from single countries, all from the developed world except one.”

In the paper

“Seven of the metaanalyses were of moderate or high quality (score 8-10); the majority were also assessed as containing evidence of moderate GRADE quality (Table 3).”

In the paper

“For forty-nine measures, information could be sourced which allowed mapping using a two-dimensional framework 18 (Figure 2).”

What the sources say

• Not checked yetcites [18] Valtorta, 2016, Loneliness, social isolation and social relationships: what are we measuring? A novel framework for classifying and comparing tools, BMJ Open

In the paper

“When assessed using the AMSTAR checklist, seventeen of the systematic reviews were of moderate quality (score 5-7) and thirteen of low quality (score 0-4).”

In the paper

“Of the forty systematic reviews included in this overview, ten involved a meta-analysis.”

In the paper

“Narrative systematic reviews suggest associations with poorer mental health outcomes, with less strong evidence for behavioural and other physical health outcomes.”

In the paper

“Forty systematic reviews of mainly observational studies were identified, largely from the developed world.”

In the paper

“Loneliness of parents and social isolation of adolescent sex offenders have been associated with child abuse in another systematic review and a meta-analysis 35, 36”

What the sources say

• Not checked yetcites [35] Black, 2001, Risk factors for child physical abuse, Aggress Violent Behav source
• Not checked yetcites [36] Seto, 2010, What is so special about male adolescent sexual offending? A review and test of explanations through meta-analysis, Psychol Bull source

In the paper

“One review found that a low sense of belonging was associated with a higher risk of suicidal ideation and suicide attempts”

What the sources say

• Not checked yetcites [52] Hatcher, 2013, Sense of belonging and suicide: a systematic review, Can J Psychiatry Revue Can De Psychiatrie source

In the paper

“shows that there is strong evidence that both social isolation and loneliness are associated with increased all-cause mortality, and social isolation with cardiovascular disease and depression (Table 4).”

• Also stated in: § Main findings · boosted

  “This overview has identified that there is strong evidence that both social isolation and loneliness are associated with increased all-cause mortality.”

In the paper

“in one of these reviews a positive association between loneliness and tobacco use was reported in half of the included studies, whereas the other half reported no association or a negative association 27 .”

What the sources say

• Not checked yetcites [27] Dyal, 2015, A systematic review of loneliness and smoking: small effects, big implications, Subst Use Misuse source

In the paper

“with individuals with stronger social relationships having a 50% increased likelihood of survival, with no variation between gender 41”

What the sources say

• Not checked yetcites [41] Glozier, 2013, Psychosocial risk factors for coronary heart disease, Med J Aust source

In the paper

“one suggested that social isolation may lead to reduced interaction and increased use of online sources of advice, potentially leading to sub-optimal adherence to treatments 37”

What the sources say

• Not checked yetcites [37] De Freitas, 2013, Vulnerabilities to misinformation in online pharmaceutical marketing, J R Soc Med source

In the paper

“One meta-analysis found an association between subjective mental wellbeing and social relationships, with the quality of relationships more important than the quantity of them 25 .”

What the sources say

• Not checked yetcites [25] Pinquart, 2000, Influences of socioeconomic status, social network, and competence on subjective well-being in later life: a meta-analysis, Psychol Aging source

In the paper

“A meta-analysis identified an association between social isolation and social anxiety disorder, though causality was unclear 51 .”

What the sources say

• Not checked yetcites [51] Teo, 2013, The role of social isolation in social anxiety disorder: a systematic review and meta-analysis, J Anxiety Disord source

In the paper

“Two systematic reviews identified that loneliness and low social participation were associated with an increased risk of dementia”

What the sources say

• Not checked yetcites [57] Boss, 2015, Loneliness and cognitive function in the older adult: a systematic review, Int Psychogeriatr source
• Not checked yetcites [58] Kuiper, 2015, Social relationships and risk of dementia: a systematic review and meta-analysis of longitudinal cohort studies, Ageing Res Rev source

In the paper

“| Suicide (Fassberg et al 2012, Hatcher et al 2013, Mezuk et al 2014, Mollinson et al 2014, Pompili 2012) | + | + | + |”

What the sources say

• Not checked yetcites Fassberg et al 2012 source
• Not checked yetcites Hatcher et al 2013 source
• Not checked yetcites Mezuk et al 2014 source

In the paper

“| Other physical health (Barton et al 2015, Steenstra et al 2005) | + | | + |”

What the sources say

• Not checked yetcites Barton et al 2015
• Not checked yetcites Steenstra et al 2005 source

In the paper

“| Depression and anxiety (Ouimet et al 2001, Kita et al 2015, Santini et al 2015, Schwarzbach et al 2014, Teo et al 2013) | ++ | | + |”

What the sources say

• Not checked yetcites Ouimet et al 2001 source
• Not checked yetcites Kita et al 2015 source
• Not checked yetcites Santini et al 2015 source

In the paper

“| Physical activity (Vancampfort et al 2012a, Vancampfort et al 2012b) | + | | |”

What the sources say

• Not checked yetcites Vancampfort et al 2012a
• Not checked yetcites Vancampfort et al 2012b

In the paper

“| Diet (Van der Pols-Vijlbrief et al 2014) | | + | |”

What the sources say

• Not checked yetcites Van der Pols-Vijlbrief et al 2014 source

In the paper

“| Other physical health (Barton et al 2015, Steenstra et al 2005) | + | | + |”

What the sources say

• Not checked yetcites Barton et al 2015
• Not checked yetcites Steenstra et al 2005 source

In the paper

“a number of non-systematic reviews have identified associations with changes to brain structure and processes, sympathetic neural tone, vascular stress responses, altered sleep and reduced sleep quality, cortisol secretion patterns, impaired cellular and humoral immunity, and reduced inflammatory responses 61, 80, 96, 102-106 .”

What the sources say

• Not checked yetcites [61] Hawkley, 2010, Loneliness matters: a theoretical and empirical review of consequences and mechanisms, Ann Behav Med source
• Not checked yetcites [80] Hawkley, 2003, Loneliness and pathways to disease, Brain Behav Immun source
• Not checked yetcites [96] West, 1986, The effects of loneliness – a review of the literature, Compr Psychiatry source
• Not checked yetcites [102] Cacioppo, 2014, Toward a neurology of loneliness, Psychol Bull source
• Not checked yetcites [103] Cacioppo, 2011, Social isolation
• Not checked yetcites [104] Hawkley, 2012, Effects of social isolation on glucocorticoid regulation in social mammals, Horm Behav source
• Not checked yetcites [105] Knutson, 2013, Sociodemographic and cultural determinants of sleep deficiency: implications for cardiometabolic disease risk, Soc Sci Med source
• Not checked yetcites [106] Local Government Association and Improvement and Development Agency, 2010

In the paper

“| Tobacco use (Barbosa et al 2012, Dyal & Valente 2015, Seo et al 2012) | + | + | |”

What the sources say

• Not checked yetcites Barbosa et al 2012 source
• Not checked yetcites Dyal & Valente 2015 source
• Not checked yetcites Seo et al 2012 source

In the paper

“| Sexual health behaviours (Black et al 2000, Herbst et al 2008, Seto & Lalumiere 2010*) | + | + | |”

What the sources say

• Not checked yetcites Black et al 2000
• Not checked yetcites Herbst et al 2008 source
• Not checked yetcites Seto & Lalumiere 2010* source

In the paper

“| Tobacco use (Barbosa et al 2012, Dyal & Valente 2015, Seo et al 2012) | + | + | |”

What the sources say

• Not checked yetcites Barbosa et al 2012 source
• Not checked yetcites Dyal & Valente 2015 source
• Not checked yetcites Seo et al 2012 source

In the paper

“| General health & wellbeing (Aminzadeh & Dalziel 2002, Annear et al 2014, Chen et al 2014, Pinquart & Sorensen 2000) | + | + | |”

What the sources say

• Not checked yetcites Aminzadeh & Dalziel 2002 source
• Not checked yetcites Annear et al 2014 source
• Not checked yetcites Chen et al 2014 source

In the paper

“| Sexual health behaviours (Black et al 2000, Herbst et al 2008, Seto & Lalumiere 2010*) | + | + | |”

What the sources say

• Not checked yetcites Black et al 2000
• Not checked yetcites Herbst et al 2008 source
• Not checked yetcites Seto & Lalumiere 2010* source

In the paper

“while the other 19 found a stronger effect for individuals aged less than 65 years.”

What the sources say

• Not checked yetcites [19] Holt-Lunstad, 2015, Loneliness and social isolation as risk factors for mortality: a meta-analytic review, Perspect Psychol Sci source

In the paper

“| Cardiovascular disease (Bunker et al 2003, Cuffee et al 2015, Glozier et al 2013, Mookadam et al 2004, Steptoe et al 2013) | ++ | | |”

What the sources say

• Not checked yetcites Bunker et al 2003 source
• Not checked yetcites Cuffee et al 2015
• Not checked yetcites Glozier et al 2013 source

In the paper

“| All-cause mortality (Holt Lunstad et al 2010*, Holt Lunstad et al 2015*, Nyqvist et al 2013*, Shor & Roelfs 2015) | ++ | ++ | ++ |”

What the sources say

• Not checked yetcites Holt Lunstad et al 2010* source
• Not checked yetcites Holt Lunstad et al 2015* source
• Not checked yetcites Nyqvist et al 2013*

In the paper

“| Adherence to treatment (De Freitas et al 2013, Denhaerynck et al 2009) | + | | |”

What the sources say

• Not checked yetcites De Freitas et al 2013 source
• Not checked yetcites Denhaerynck et al 2009

In the paper

“| All-cause mortality (Holt Lunstad et al 2010*, Holt Lunstad et al 2015*, Nyqvist et al 2013*, Shor & Roelfs 2015) | ++ | ++ | ++ |”

What the sources say

• Not checked yetcites Holt Lunstad et al 2010* source
• Not checked yetcites Holt Lunstad et al 2015* source
• Not checked yetcites Nyqvist et al 2013*

In the paper

“| General health & wellbeing (Aminzadeh & Dalziel 2002, Annear et al 2014, Chen et al 2014, Pinquart & Sorensen 2000) | + | + | |”

What the sources say

• Not checked yetcites Aminzadeh & Dalziel 2002 source
• Not checked yetcites Annear et al 2014 source
• Not checked yetcites Chen et al 2014 source

In the paper

“| All-cause mortality (Holt Lunstad et al 2010*, Holt Lunstad et al 2015*, Nyqvist et al 2013*, Shor & Roelfs 2015) | ++ | ++ | ++ |”

What the sources say

• Not checked yetcites Holt Lunstad et al 2010* source
• Not checked yetcites Holt Lunstad et al 2015* source
• Not checked yetcites Nyqvist et al 2013*

In the paper

“| Behaviour change (Murray et al 2012) | | | + |”

What the sources say

• Not checked yetcites Murray et al 2012 source

In the paper

“| Depression and anxiety (Ouimet et al 2001, Kita et al 2015, Santini et al 2015, Schwarzbach et al 2014, Teo et al 2013) | ++ | | + |”

What the sources say

• Not checked yetcites Ouimet et al 2001 source
• Not checked yetcites Kita et al 2015 source
• Not checked yetcites Santini et al 2015 source

In the paper

“| Cancer (Pinquart & Duberstein 2010*) | | | + |”

What the sources say

• Not checked yetcites Pinquart & Duberstein 2010* source

In the paper

“though social isolation and loneliness of children may be associated with abuse or poorer developmental and educational outcomes 65, 87, 97, 99-101 .”

What the sources say

• Not checked yetcites [65] Public Health England, 2015
• Not checked yetcites [87] Merrick, 2006, A review of suicidality in persons with intellectual disability, Israel J Psychiatry Relat Sci
• Not checked yetcites [97] Anooshian, 2005, Violence and aggression in the lives of homeless children: a review, Aggress Violent Behav source
• Not checked yetcites [99] Vizard, 1995, Child and adolescent sex abuse perpetrators – a review of the research literature, J Child Psychol Psychiatry Allied Discip source
• Not checked yetcites [100] Whittle, 2013, A review of young people's vulnerabilities to online grooming, Aggress Violent Behav source
• Not checked yetcites [101] Normand, 2016, Cybervictimization of young people with an intellectual or developmental disability: risks specific to sexual solicitation, J Appl Res Intellect Disabil source

In the paper

“| Suicide (Fassberg et al 2012, Hatcher et al 2013, Mezuk et al 2014, Mollinson et al 2014, Pompili 2012) | + | + | + |”

What the sources say

• Not checked yetcites Fassberg et al 2012 source
• Not checked yetcites Hatcher et al 2013 source
• Not checked yetcites Mezuk et al 2014 source

In the paper

“Less is known on the role of other conditions and wider socio-economic consequences”

In the paper

“| Dementia (Boss et al 2015, Kuiper et al 2015*) | | + | |”

What the sources say

• Not checked yetcites Boss et al 2015 source
• Not checked yetcites Kuiper et al 2015* source

In the paper

“| Suicide (Fassberg et al 2012, Hatcher et al 2013, Mezuk et al 2014, Mollinson et al 2014, Pompili 2012) | + | + | + |”

What the sources say

• Not checked yetcites Fassberg et al 2012 source
• Not checked yetcites Hatcher et al 2013 source
• Not checked yetcites Mezuk et al 2014 source

In the paper

“While loneliness may be more common in the elderly, it also affects younger age groups 6 .”

What the sources say

• Not checked yetcites [6] Griffin, 2010

In the paper

“the quality of evidence within these reviews using the GRADE approach”

• Also stated in: § Methods · plain

  “the quality of the evidence in these reviews was assessed using the GRADE approach 17 .”

What the sources say

• Not checked yetcites [17] GRADE working group, 2011

In the paper

“Surveys in Europe and the USA estimate the prevalence of loneliness ranges from 5% to 43% in the elderly 1-4 , with similar figures for China 5 .”

What the sources say

• Not checked yetcites [1] Office of National Statistics, 2013
• Not checked yetcites [2] Dykstra, 2009, Older adult loneliness: myths and realities, Eur J Ageing source
• Not checked yetcites [3] Sörensen, 2000, Vulnerability and access to resources as predictors of preparation for future care needs in the elderly, J Aging Health source
• Not checked yetcites [4] Perissinotto, 2012, Loneliness in older persons: a predictor of functional decline and death, Arch Intern Med source

In the paper

“Data were extracted from the selected reviews using a pre-designed data extraction sheet to standardise reporting of results across the included reviews.”

In the paper

“Differences of opinion were discussed and consensus reached over inclusion or exclusion of the study.”

In the paper

“but determining causality is difficult as much of the research in this area involves observational studies.”

In the paper

“Methodology for this overview followed recognised guidance for conducting systematic overviews 14, 15 .”

What the sources say

• Not checked yetcites [14] Becker, 2011
• Not checked yetcites [15] Smith, 2011, Methodology in conducting a systematic review of systematic reviews of healthcare interventions, BMC Med Res Methodol source

In the paper

“the methodological quality of included systematic reviews assessed using the AMSTAR checklist”

• Also stated in: § Methods · plain

  “The methodological quality of the reviews selected for inclusion was also assessed by two reviewers for each review, using the AMSTAR checklist 16”

What the sources say

• Not checked yetcites [16] Shea, 2007, Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews, BMC Med Res Methodol source

In the paper

“Suitability for inclusion was determined by two or more reviewers”

• Also stated in: § Methods · plain

  “The process was confirmed by a second reviewer to ensure validity of inclusion.”

In the paper

“with similar figures for China 5 .”

What the sources say

• Not checked yetcites [5] Yang, 2008, The prevalence of and risk factors for loneliness among older people in China, Ageing Soc source

In the paper

“The role of social isolation and loneliness in other conditions and their socio-economic consequences is less clear.”

In the paper

“though causality could not be proven and other variables may have confounded the relationship 29 .”

What the sources say

• Not checked yetcites [29] Seo, 2012, Systematic review of social network analysis in adolescent cigarette smoking behavior, J Sch Health source

In the paper

“While proof of causality cannot be confirmed, this may be mediated through the cardiovascular system and mental health.”

In the paper

“Most of the research in this overview came from developed countries and only English language publications were considered, so this may limit applicability of findings elsewhere.”

In the paper

“very few of the reviews contained longitudinal studies so causality cannot be inferred from the associations identified.”

In the paper

“As all of the tools used in the reviews were self-report measures which depend on the degree of subjectivity from respondents, findings should also be considered with caution.”

In the paper

“No reviews considered health economic considerations, so this review is not able to give insight into wider socio-economic consequences of social isolation and loneliness.”

In the paper

“Most of the systematic reviews were of moderate quality but none were of high quality, which most likely is a reflection of them containing predominantly observational studies”