Association of loneliness with all-cause mortality: A meta-analysis

PLoS One. 2018 Jan 4;13(1):e0190033. doi: 10.1371/journal.pone.0190033. eCollection 2018.


Introduction: Loneliness has social and health implications. The aim of this article is to evaluate the association of loneliness with all-cause mortality.

Methods: Pubmed, PsycINFO, CINAHL and Scopus databases were searched through June 2016 for published articles that measured loneliness and mortality. The main characteristics and the effect size values of each article were extracted. Moreover, an evaluation of the quality of the articles included was also carried out. A meta-analysis was performed firstly with all the included articles and secondly separating by gender, using a random effects model.

Results: A total of 35 articles involving 77220 participants were included in the systematic review. Loneliness is a risk factor for all-cause mortality [pooled HR = 1.22, 95% CI = (1.10, 1.35), p < 0.001] for both genders together, and for women [pooled HR = 1.26, 95% CI = (1.07, 1.48); p = 0.005] and men [pooled HR = 1.44; 95% CI = (1.19, 1.76); p < 0.001] separately.

Conclusions: Loneliness shows a harmful effect for all-cause mortality and this effect is slightly stronger in men than in women. Moreover, the impact of loneliness was independent from the quality evaluation of each article and the effect of depression.

Publication types

  • Meta-Analysis
  • Research Support, Non-U.S. Gov't
  • Systematic Review

MeSH terms

  • Cause of Death*
  • Humans
  • Loneliness*
  • Risk Factors

Grants and funding

The research leading to these results has received funding from the European Commission Horizon 2020 under the project Ageing Trajectories of Health: Longitudinal Opportunities and Synergies with the grant number 635316 (, and from the Instituto de Salud Carlos III-FIS research grant number PI13/00059 ( The project PI13/00059 has been co-funded by the European Union European Regional Development Fund (ERDF) “A Way to Build Europe”. Laura Rico and Natalia Martín-María are supported by the program "Contratos predoctorales para Formación de Personal Investigador, FPI-UAM", Universidad Autónoma de Madrid, Spain ( The work was supported by the Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Instituto de Salud Carlos III ( The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.