Do the mortality findings hold in low and middle income countries?

Evidence regarding mortality risks in low- and middle-income countries (LMICs) is thinly evidenced in this corpus. Most meta-analyses and large-scale cohort studies, such as the meta-analysis of 90 cohort studies covering over 2 million adults (Wang, 2023) and the English Longitudinal Study of Ageing (Steptoe, 2013), rely predominantly on high-income cohorts. The corpus lacks primary studies or reviews specifically focused on marginalized groups or LMIC populations. Consequently, the honest answer is that we do not know if these mortality findings hold in those contexts. For the general populations studied, both social isolation and loneliness are associated with higher all-cause mortality (Wang, 2023). A meta-analysis reported pooled effect sizes of 1.32 for social isolation and 1.14 for loneliness (Wang, 2023). However, these estimates come from cohorts with varying adjustment, and the signal for loneliness does not always survive adjustment for objective isolation (Steptoe, 2013). Most mortality meta-analyses exclude deaths from suicide and unnatural causes, which may make these estimates conservative. Finally, while social vulnerability is linked to mortality, studies on missed appointments often lack a social connection variable and should not be used to infer engagement patterns for lonely individuals (McQueenie, 2019).

Sources

  1. Holt-Lunstad et al., 2010 — Social Relationships and Mortality Risk: A Meta-analytic Review Read the source
  2. Holt-Lunstad J et al., 2015 — Loneliness and social isolation as risk factors for mortality: a meta-analytic review Read the source
  3. Wang F et al., 2023 — A systematic review and meta-analysis of 90 cohort studies of social isolation, loneliness and mortality Read the source
  4. Holt-Lunstad et al., 2018 — Why Social Relationships Are Important for Physical Health: A Systems Approach to Understanding and Modifying Risk and Protection Read the source
  5. Hanlon et al., 2024 — The relationship between frailty and social vulnerability: a systematic review Read the source
  6. McQueenie et al., 2019 — Morbidity, mortality and missed appointments in healthcare: a national retrospective data linkage study Read the source
  7. Steptoe et al., 2013 — Social isolation, loneliness, and all-cause mortality in older men and women Read the source
  8. Yang et al., 2013 — Social Isolation and Adult Mortality: The Role of Chronic Inflammation and Sex Differences Read the source
  9. Hilliard et al., 2026 — Investigating relationships between loneliness, social isolation and health Read the source