CoChat
Sign Up
Cited by 507Health disparities and outcomesCardiac Health and Mental HealthDeath Anxiety and Social Exclusion

The DOI matches its Crossref record; 149 of the 149 references it cites were found in a registry or an index; 6 of the 9 sources its claims cite were checked for support.

A systematic review and meta-analysis of 90 cohort studies of social isolation, loneliness and mortality

Open access
Wang, Fan, Gao, Yu, Han, Zhen, Yu, Yue, Long, Zhiping, Jiang, Xianchen, Wu, Yi, Pei, Bing, Cao, Yukun, Ye, Jingyu, Wang, Maoqing, Zhao, Yashuang·2023·Nature Human Behaviour
DOI 10.1038/s41562-023-01617-6

Published version of a preprint

Open this paper in CoChat — free accountOpen PDF

Abstract

Abstract Background We aimed to assess the associations between social isolation (SI) and the risk of mortality from all causes, cardiovascular disease, and cancer. Methods This was a systematic review and meta-analysis of prospective cohort studies.We searched electronic databases, including PubMed, Web of Science, and Embase, from inception until October 2021, as well as the references of retrieved articles. Prospective studies reporting risk estimates for the association between SI and mortality from all causes, cardiovascular diseases, and cancer in adults aged 18 or older were included in the analyses. Data were screened and extracted independently by two investigators. The fully adjusted effect sizes in the original studies were analyzed, and summary analyses were performed using a fixed-effects or random-effects model, according to the heterogeneity among studies. Subgroup analyses, meta-regression, and sensitivity analyses were performed to evaluate the heterogeneity and robustness of the findings. Simple linear regression was used to analyze the changing trends in social network index grade and risk of mortality. The risk of publication bias was tested using funnel plots and Egger’s and Begg’s tests (each significant at P < 0.05). The trim-and-fill method was used to adjust for the influence of potentially unpublished studies on pooled effect estimates when statistical tests indicated publication bias. The study protocol was registered with PROSPERO (reg. NO CRD42022299959) Results A total of 50 prospective cohort studies with 1,951,661 individuals were included for analysis. The duration of follow-up among included studies ranged from 6 months to 24.4 years. In pooled analyses, SI was significantly associated with an increased risk of mortality from all causes (pooled effect size, 1.22; 95% confidence interval [CI], 1.16 to 1.29; I2 = 77.6%), cardiovascular disease (1.35; 95% CI 1.25 to 1.45, I2 = 65.5%), and cancer (1.23; 95% CI 1.18 to 1.27, I2 = 44.2%) in the general population. Linear regression showed that social network index grade was significantly correlated with the risk of all-cause mortality (P < 0.001). Additionally, the pooled effect estimate for all-cause mortality in patients with breast cancer was 1.51 (95% CI 1.34 to 1.70), and that for cancer-specific mortality was 1.33 (95% CI 1.02 to 1.75). There was a 28% increased risk of all-cause mortality in socially isolated patients with cardiovascular disease (95% CI 1.10 to 1.48). There was no evidence of a positive association between SI and cancer-specific mortality in patients with colorectal cancer (1.07, 95% CI 0.96 to 1.20). Conclusions SI was associated with at least a 20% increased risk of all-cause mortality, cardiovascular disease mortality, and cancer mortality. We highlight that social isolation contributes to chronic disease and mortality, with efforts to improve social isolation likely to have benefits in well-being and survival.

Overview

AI snapshot

Written from the paper’s full text.

TL;DR

This systematic review and meta-analysis of 50 prospective cohort studies (1,951,661 individuals) found that social isolation was associated with increased mortality from all causes, cardiovascular disease, and cancer in the general population. The highest risk was for cardiovascular mortality, and associations were also observed in patients with cardiovascular disease and breast cancer.

Key findings

  • Social isolation was significantly associated with all-cause mortality (pooled effect estimate 1.31, 95% CI 1.23–1.38; I² = 77.6%), which remained after trim-and-fill adjustment (1.22, 95% CI 1.16–1.29).
  • Pooled estimates were 1.35 (95% CI 1.25–1.45, I² = 65.5%) for cardiovascular/circulatory disease mortality and 1.23 (95% CI 1.18–1.27, I² = 44.2%) for cancer mortality.
  • In patient populations: all-cause mortality was 1.28 (95% CI 1.10–1.48) in patients with CVD; in breast cancer, all-cause mortality was 1.51 (95% CI 1.34–1.70) and cancer-specific mortality 1.33 (95% CI 1.02–1.75). No significant association was found for cancer-specific mortality in colorectal cancer (1.07, 95% CI 0.96–1.20).
  • Social Network Index grade was significantly correlated with all-cause mortality risk (P < 0.001), with mortality increasing as isolation increased.

Methods

  • Systematic review and meta-analysis of prospective cohort studies; PubMed, Web of Science, and Embase searched from inception to October 2021, plus reference lists; protocol registered with PROSPERO (CRD42022299959).
  • 50 prospective cohort studies with 1,951,661 participants aged ≥18 years (most ≥50 years); follow-up ranged from 6 months to 24.4 years; 23 studies were from the United States.
  • Fully adjusted effect sizes (HR/RR/OR with 95% CIs) were pooled using fixed- or random-effects models according to heterogeneity (I² ≥ 50% random effects); subgroup analyses, meta-regression, sensitivity analyses, and publication bias tests (funnel plots, Egger's and Begg's tests, trim-and-fill) were performed.

Limitations

  • Stated: adjustment factors varied greatly across original studies, making the source of heterogeneity complex and difficult to trace; potential unknown confounders may remain; definitions and instruments for social isolation were not consistent across studies; most included studies came from high-income countries; and early deaths were not excluded in the original studies.
  • Evident from the text: significant publication bias was detected for the all-cause mortality analysis (Egger's P = 0.037; Begg's P = 0.036), and heterogeneity was substantial (I² = 77.6%).

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1038/s41562-023-01617-6

Cites

149 of 149 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Verification

Claims the paper makes

6 of 9 cited sources checked · 0 supported · 0 flagged · accuracy not yet measured

  • Premisecitation

    Socially isolated individuals are less likely to receive emergency and routine medical care owing to their smaller social network.

    “Finally, in terms of social factors, socially isolated individuals are less likely to receive emergency and routine medical care owing to their smaller social network if they need help and have no means of transportation 90 .”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [90] Tilvis, R. S., Laitala, V., Routasalo, P. E. & Pitkälä, K. H. Suffering from loneliness indicates significant mortality risk of older people. J. Aging Res. 2011, 534781 (2011). source

      The Introduction distinguishes social isolation from loneliness and mentions increased use of social and health services in studies of loneliness. Neither the Introduction nor the Discussion addresses whether socially isolated people receive less emergency or routine care because they lack contacts or transportation. Searches for those care-access and transportation claims found no supporting passage in our copy. (LLM, conf=0.77)

      Experimental — accuracy not yet measured
  • Premisecitation

    Bower et al. reported systematic upregulation of multiple prometastatic molecular processes in primary breast tumors among socially isolated patients with breast cancer.

    “Additionally, Bower et al. 91 reported systematic upregulation of multiple prometastatic molecular processes in primary breast tumors among socially isolated patients with breast cancer.”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [91] Shiovitz-Ezra, S. & Ayalon, L. Situational versus chronic loneliness as risk factors for all-cause mortality. Int. Psychogeriatr. 22, 455–462 (2010). source

      The Introduction discusses social isolation and health outcomes in older adults, while the Results address loneliness and all-cause mortality. Searches for Bower, primary breast tumors, and prometastatic processes found no passage in our copy addressing the claimed finding. (LLM, conf=0.76)

      Experimental — accuracy not yet measured
  • Findingown data

    Social isolation was significantly associated with an increased risk of cardiovascular disease mortality in the general population (pooled effect size 1.35; 95% CI 1.25 to 1.45; I2 = 65.5%).

    “cardiovascular disease (1.35; 95% CI 1.25 to 1.45, I 2 = 65.5%)”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Different methods used to assess social isolation in the included studies measure the same underlying exposure sufficiently to be pooled in a single meta-analysis.
    • Rests on an assumption: Hazard ratios, risk ratios, and odds ratios from the included studies are comparable and can be combined to produce pooled effect estimates.
    • Rests on an assumption: The most fully adjusted effect estimates from the included studies adequately control for confounding, so the pooled associations can be interpreted as independent effects of social isolation.
  • Findingown data

    Social isolation was significantly associated with an increased risk of cancer mortality in the general population (pooled effect size 1.23; 95% CI 1.18 to 1.27; I2 = 44.2%).

    “and cancer (1.23; 95% CI 1.18 to 1.27, I 2 = 44.2%) in the general population.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: Different methods used to assess social isolation in the included studies measure the same underlying exposure sufficiently to be pooled in a single meta-analysis.
    • Rests on an assumption: Hazard ratios, risk ratios, and odds ratios from the included studies are comparable and can be combined to produce pooled effect estimates.
    • Rests on an assumption: The most fully adjusted effect estimates from the included studies adequately control for confounding, so the pooled associations can be interpreted as independent effects of social isolation.
  • Findingown data

    In men, after trim-and-fill adjustment, the pooled effect estimate for all-cause mortality was 1.35 (95% CI 1.20 to 1.51).

    “and 1.35 (95% CI 1.20 to 1.51) after adjustment using the trim-and-ll method”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: Different methods used to assess social isolation in the included studies measure the same underlying exposure sufficiently to be pooled in a single meta-analysis.
    • Rests on an assumption: Hazard ratios, risk ratios, and odds ratios from the included studies are comparable and can be combined to produce pooled effect estimates.
    • Rests on an assumption: The most fully adjusted effect estimates from the included studies adequately control for confounding, so the pooled associations can be interpreted as independent effects of social isolation.
  • Probably not a substantial claim. 18
  • It may state two separate claims as one. 17

  • Probably not a substantial claim.

    Study design and conductreasoning

    The Newcastle-Ottawa quality assessment scale for cohort studies was used to evaluate methodological quality.

    “Because all eligible studies had a cohort study design, the Newcastle-Ottawa quality assessment scale for cohort studies was used to evaluate methodological quality 30 31 .”
    Quote in the paperSubstantial claim2 of 2 sources checked
    • cites [30] Kraav, S. L. et al. The effects of loneliness and social isolation on all-cause, injury, cancer, and CVD mortality in a cohort of middle-aged Finnish men: a prospective study. Aging Ment. Health 25, 2219–2228 (2021). source

      The Sample section describes a prospective study of Finnish men, supporting its identification as a cohort study. The Statistical Methods section describes the paper’s analyses but does not mention the Newcastle–Ottawa scale or an assessment of methodological quality. The paper therefore supports the cohort-design part of the sentence, not the scale-use part. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
    • cites [31] Crowe, C. L. et al. Associations of loneliness and social isolation with health span and life span in the U.S. Health and Retirement Study. J. Gerontol. A 76, 1997–2006 (2021). source

      The Statistical Analysis and Sensitivity Analysis sections describe analyses of the Health and Retirement Study cohort, not quality appraisal of a set of eligible studies (page numbers unavailable). Searches for the Newcastle–Ottawa scale and methodological quality assessment found no passage addressing their use. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductcitation

    The findings were reported based on the PRISMA guideline.

    “The ndings from this systematic review and meta-analysis were reported based on the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 23 guideline (Table S1).”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [23] Yu, B. et al. Social isolation, loneliness, and all-cause mortality in patients with cardiovascular disease: a 10-year follow-up study. Psychosom. Med. 82, 208–214 (2020). source

      The Methods and Figure 1 passages describe a follow-up analysis of Taiwanese survey and insurance-claims data, not the reporting of a systematic review. Searches of our copy for PRISMA and systematic-review reporting found no passage addressing whether the citing review followed that guideline. Page numbers were not available in our copy. (LLM, conf=0.75)

      Experimental — accuracy not yet measured

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. It may state two separate claims as one.

    Premisecitation

    Social isolation is more common among people with lower levels of education and those who are unemployed.

    “possibly because SI is more common among people with lower levels of education and those who are unemployed 17 .”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [17] Novak, M. et al. Cardiovascular and all-cause mortality attributable to loneliness in older Swedish men and women. BMC Geriatr. 20, 201 (2020). source

      The Results section (‘Loneliness and background characteristics’; page unavailable) reports that loneliness was more common among participants with poor economic status, but it does not report an association with lower education or unemployment. The Methods section (‘Assessment of loneliness’; page unavailable) measures self-reported loneliness rather than social isolation. Searches for education, employment, and social isolation found no passage establishing the claimed associations. (LLM, conf=0.76)

      Experimental — accuracy not yet measured

  • It may state two separate claims as one.

    Findingown data

    In subgroup analysis for cardiovascular disease mortality, no significant differences were observed for sex, country, follow-up duration, or adjustment for confounding, except for education level (P = 0.029).

    “According to the results of subgroup analysis, no signi cant differences were observed for sex, country, follow-up duration, or adjustment for confounding, except for education level (P = 0.029; Table S9).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Findingown data

    Social isolation (SI) is positively associated with mortality from all causes, cardiovascular or circulatory diseases, and cancer.

    “We demonstrated that SI is positively associated with mortality from all causes, cardiovascular or circulatory diseases, and cancer.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingown data

    The duration of follow-up among included studies ranged from 6 months to 24.4 years.

    “The duration of follow-up among included studies ranged from 6 months to 24.4 years.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Findingnone given

    Early deaths were not excluded in the original study.

    “Since early deaths were not excluded in the original study, which may confound the relationship between social isolation and mortality in the original study”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds. It may state two separate claims as one.

    Interpretationnone given

    SI may be exacerbated by post-cancer or CVD stress and less social contact as well as limited access to care, especially informal care from friends and family.

    “SI may be exacerbated by post-cancer or CVD stress and less social contact as well as limited access to care, especially informal care from friends and family.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductnone given

    Data were screened and extracted independently by two investigators.

    “Data were screened and extracted independently by two investigators.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it. The paper may give no reason why it holds.

    Interpretationreasoning

    In socially isolated patients with cancer, death is more often owing to inaccessibility of long-term medical services and basic care in the late stages of disease.

    “By contrast, in socially isolated patients with cancer, death is more often owing to inaccessibility of long-term medical services and basic care in the late stages of disease.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductnone given

    Although many confounders had been adjusted in the original studies, there were still potential unknown confounders.

    “Although many confounders had been adjusted in the original studies, there were still potential unknown confounders.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    Social isolation was associated with at least a 20% increased risk of all-cause mortality, cardiovascular disease mortality, and cancer mortality.

    “SI was associated with at least a 20% increased risk of all-cause mortality, cardiovascular disease mortality, and cancer mortality.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between social isolation and mortality reflect a causal effect of social isolation rather than residual confounding or reverse causation.

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Interpretationreasoning

    Not excluding early deaths may confound the relationship between social isolation and mortality in the original study.

    “Since early deaths were not excluded in the original study, which may confound the relationship between social isolation and mortality in the original study”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    People who are socially isolated are more likely to be depressed or suicidal.

    “Second, in terms of psychological factors, studies have shown that people who are socially isolated are more likely to be depressed or suicidal 89 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [89] Tilvis, R. S., Laitala, V., Routasalo, P., Strandberg, T. E. & Pitkala, K. H. Positive life orientation predicts good survival prognosis in old age. Arch. Gerontol. Geriatr. 55, 133–137 (2012). source

  • It may state two separate claims as one.

    Interpretationreasoning

    Efforts to improve social isolation likely have benefits in well-being and survival.

    “with efforts to improve social isolation likely to have bene ts in well-being and survival.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductreasoning

    The trim-and-fill method was used to adjust for potentially unpublished studies when statistical tests indicated publication bias.

    “The trim-and-ll method was used to adjust for the in uence of potentially unpublished studies on pooled effect estimates when statistical tests indicated publication bias.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Study design and conductown data

    Most included studies had a low risk of bias and were high-quality studies.

    “Based on the Newcastle-Ottawa scale, most studies had a low risk of bias in all components.Most studies had a rating of 7-8 and were identi ed as high-quality studies, with only four studies that had a rating of 6 that were considered moderate-quality studies.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    Social isolation was positively correlated with all-cause mortality in the overall population and in both men and women.

    “Thus, we could con rm that SI was positively correlated with all-cause mortality in the overall population and in both men and women.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Premisecitation

    Higher levels of inflammatory markers like C-reactive protein and fibrinogen are closely associated with cardiovascular disease and mortality.

    “Higher levels of in ammatory markers like C-reactive protein and brinogen, are closely associated with CVD and mortality 88 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [88] Holwerda, T. J. et al. Increased risk of mortality associated with social isolation in older men: only when feeling lonely? Results from the Amsterdam Study of the Elderly (AMSTEL). Psychol. Med. 42, 843–853 (2012). source

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductown data

    The risk of publication bias was tested using funnel plots and Egger's and Begg's tests.

    “The risk of publication bias was tested using funnel plots and Egger's and Begg's tests (each signi cant at P < 0.05).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Study design and conductown data

    No significant heterogeneity or publication bias was found for breast and colorectal cancer mortality analyses.

    “No signi cant heterogeneity or publication bias was found (Table S6).”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Study design and conductnone given

    There was a large number of internal adjustment factors in the original studies, and adjustment factors varied greatly among studies.

    “There was a large number of internal adjustment factors in the original studies, and adjustment factors varied greatly among studies.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Interpretationown data

    Social isolation contributes to chronic disease and mortality.

    “We highlight that social isolation contributes to chronic disease and mortality”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The observed associations between social isolation and mortality reflect a causal effect of social isolation rather than residual confounding or reverse causation.

  • Probably not a substantial claim.

    Study design and conductown data

    Subgroup analyses, meta-regression, and sensitivity analyses were performed to evaluate heterogeneity and robustness.

    “Subgroup analyses, meta-regression, and sensitivity analyses were performed to evaluate the heterogeneity and robustness of the ndings.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductnone given

    The study protocol was registered with PROSPERO (registration number CRD42022299959).

    “The study protocol was registered with PROSPERO (reg.NO CRD42022299959)”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Study design and conductnone given

    Most included studies were of high quality, with a low risk of bias.

    “Most included studies were of high quality, with a low risk of bias, which further lends con dence regarding the reliability of the current pooled results.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationown data

    We found a significant association of social isolation with increased risk of all three types of mortality outcomes in the general population, with the highest risk for cardiovascular death.

    “We found a signi cant association of SI with increased risk of all three types of mortality outcomes in the general population, with the highest risk for cardiovascular death.”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Interpretationown data

    Socially isolated patients with cardiovascular disease and breast cancer had worse all-cause mortality, and patients with breast cancer and social isolation had higher cancer-specific mortality.

    “Socially isolated patients with CVD and breast cancer had worse all-cause mortality, and patients with breast cancer and SI had a higher cancer-speci c mortality.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim. The paper’s conclusions may not depend on it.

    Study design and conductown data

    A sensitivity analysis was conducted in which each prospective cohort study was excluded in turn to examine the influence of that study on the overall estimates.

    “Additionally, we conducted a sensitivity analysis, in which each prospective cohort study was excluded in turn to examine the in uence of that study on the overall estimates.”
    Quote in the paperNot a substantial claim

  • It may state two separate claims as one.

    Premisecitation

    Individuals who are socially isolated may show elevated activation of the hypothalamic-pituitary-adrenal axis, an increased chronic stress response, elevated blood pressure, and higher levels of serum cortisol.

    “First, in terms of physiological factors, individuals who are socially isolated may show elevated activation of the hypothalamic-pituitaryadrenal axis, an increased chronic stress response, elevated blood pressure, and higher levels of serum cortisol 13 .”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [13] Moreno-Tamayo, K., Juarez, F., Manrique-Espinoza, B. & Mejia-Pailles, G. The relationship between social isolation and mortality among adults aged 50 and older in a 12-year follow-up analysis in Mexico. Res. Aging 44, 758–769 (2022). source

  • Probably not a substantial claim.

    Study design and conductnone given

    The fully adjusted effect sizes in the original studies were analyzed.

    “The fully adjusted effect sizes in the original studies were analyzed”
    Quote in the paperSubstantial claim

  • It may state two separate claims as one.

    Study design and conductnone given

    The definition of SI was not completely consistent among studies, and the instruments used to evaluate SI differed.

    “The de nition of SI was not completely consistent among studies, and the instruments used to evaluate SI differed, which may affect the accuracy of the meta-analysis results.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim. It may be too vague to check against evidence. The paper’s conclusions may not depend on it.

    Interpretationreasoning

    The source of heterogeneity is complex and difficult to trace.

    “The source of heterogeneity is complex and di cult to trace.”
    Quote in the paperNot a substantial claim
33 of 33

  • The paper relies on this without support.

    Different methods used to assess social isolation in the included studies measure the same underlying exposure sufficiently to be pooled in a single meta-analysis.

    “We included all studies with SI evaluated using different methods (detailed de nitions in Table S2) in the original studies.”

  • The paper relies on this without support.

    Hazard ratios, risk ratios, and odds ratios from the included studies are comparable and can be combined to produce pooled effect estimates.

    “HRs and RRs (along with 95% CIs) for comparisons of SI with non-SI or graded variables in the original studies were summarized to calculate the pooled effect estimates for the association between SI and mortality outcomes.”

  • The paper relies on this without support.

    The most fully adjusted effect estimates from the included studies adequately control for confounding, so the pooled associations can be interpreted as independent effects of social isolation.

    “If the included studies reported both crude and multivariable-adjusted effect estimates, we extracted the most fully adjusted outcomes in the present meta-analysis.”

  • The paper relies on this without support.

    The observed associations between social isolation and mortality reflect a causal effect of social isolation rather than residual confounding or reverse causation.

    “We highlight that social isolation contributes to chronic disease and mortality”

  • The paper relies on this without support.

    The search strategy identified all relevant studies.

    “We searched PubMed, Web of Science, and Embase for studies published in English between database inception and October 2021.”

  • The paper relies on this without support.

    This was the first study to comprehensively evaluate the association between SI and mortality from all causes, CVD, and cancer.

    “To the best of our knowledge, this was the rst study to comprehensively evaluate the association between SI and mortality from all causes, CVD, and cancer.”

  • The paper relies on this without support.

    The association between SI and cancer mortality was systematically reviewed for the first time, as was the relationship between SI and mortality in patients with CVD and cancer.

    “The association between SI and cancer mortality was systematically reviewed for the rst time, as was the relationship between SI and mortality in patients with CVD and cancer.”
7 of 7

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Cancer-mortality pooled estimate changes in discussion

    Major

    The results report a pooled cancer-mortality estimate of 1.23 from 10 studies, whereas the discussion describes the summarized estimate from 10 studies as 1.18.

  • Database search lists disagree

    Minor

    The methods list three databases, but the results say the electronic search also included the Cochrane Library.

2 of 2

Citations

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. National Academies of Sciences, Engineering, and Medicine Social Isolation and Loneliness in Older Adults: Opportunities for the Health Care System (National Academies Press, 2020).
  2. ICD-9-CM. International Classification of Diseases, 9th revision, Clinical Modification. 3d edition, volumes 1, 2 and 3. Official authorized addendum effective October 1, 1990–HCFA. J. Am. Med. Rec. Assoc. 61, 1–35 (1990). Suppl.

Cited by

Sorted by citations

Related

Metadata

Authors
Wang, F., Gao, Y., Han, Z., Yu, Y., Long, Z., Jiang, X., Wu, Y., Pei, B., Cao, Y., Ye, J., Wang, M., & Zhao, Y.
Affiliations
Harbin Medical University (CN)
Corresponding author
  • Wang, Maoqing
  • Zhao, Yashuang
ORCID
Venue
Nature Human Behaviour
Publisher
Springer Science and Business Media LLC
Published
2023-06-19
Volume
7
Issue
8
Pages
1307-1319
ISSN
2397-3374 (ISSN-L)
DOI
10.1038/s41562-023-01617-6
OpenAlex
W4381190169
Semantic Scholar
357da1538277236347b083ace12770c921b2a31e
Cited by
507
References
148
Citations by year
2026: 190 · 2025: 173 · 2024: 117 · 2023: 26
FWCI
20.16
Type
journal article
Language
en
Open access
Licence
Locations
  • Nature Human Behaviour (publishedVersion)
  • Research Square (acceptedVersion, cc-by)
  • PubMed (publishedVersion)
  • RePEc: Research Papers in Economics (submittedVersion)
Funders
Dr. Wu Lien teh Science Foundation of Harbin Medical University
Topics
  • Social Sciences › Health › Health disparities and outcomes
  • Health Sciences › Medicine › Cardiology and Cardiovascular Medicine › Cardiac Health and Mental Health
  • Social Sciences › Psychology › Social Psychology › Death Anxiety and Social Exclusion
Keywords
social isolation, loneliness, mortality, all-cause mortality, cardiovascular mortality, cancer mortality, breast cancer, social determinants of health
MeSH terms
Adult, Breast Neoplasms, Cardiovascular Diseases, Female, Humans, Loneliness, Prospective Studies, Social Isolation

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

A language model drew the claims from the paper on 2026-11-07, under version 3 of the claim definition (model deepseek-v4.1-flash, prompt extract-v3).

A second model labelled each claim on 2026-11-07 (model jev-1.13-20260917, definition revision gold-guideline-v0.2).

Cited sources are checked with a language model’s help (gpt-6-sol).

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review