TY - JOUR
T1 - Social isolation, loneliness, and inflammation
T2 - A multi-cohort investigation in early and mid-adulthood
AU - Matthews, Timothy
AU - Rasmussen, Line Jee Hartmann
AU - Ambler, Antony
AU - Danese, Andrea
AU - Eugen-Olsen, Jesper
AU - Fancourt, Daisy
AU - Fisher, Helen L.
AU - Iversen, Kasper Karmark
AU - Schultz, Martin
AU - Sugden, Karen
AU - Williams, Benjamin
AU - Caspi, Avshalom
AU - Moffitt, Terrie E.
N1 - Publisher Copyright:
Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.
PY - 2024
Y1 - 2024
N2 - Social isolation and loneliness have been associated with poor health and increased risk for mortality, and inflammation might explain this link. We used data from the Danish TRIAGE Study of acutely admitted medical patients (N = 6,144, mean age 60 years), and from two population-representative birth cohorts: the New Zealand Dunedin Longitudinal Study (N = 881, age 45) and the UK Environmental Risk (E-Risk) Longitudinal Twin Study (N = 1448, age 18), to investigate associations of social isolation with three markers of systemic inflammation: C-reactive protein (CRP), interleukin-6 (IL-6), and a newer inflammation marker, soluble urokinase plasminogen activator receptor (suPAR), which is thought to index systemic chronic inflammation. In the TRIAGE Study, socially isolated patients (those living alone) had significantly higher median levels of suPAR (but not CRP or IL-6) compared with patients not living by themselves. Social isolation prospectively measured in childhood was longitudinally associated with higher CRP, IL-6, and suPAR levels in adulthood (at age 45 in the Dunedin Study and age 18 in the E-Risk Study), but only suPAR remained associated after controlling for covariates. Dunedin Study participants who reported loneliness at age 38 or age 45 had elevated suPAR at age 45. In contrast, E-Risk Study participants reporting loneliness at age 18 did not show any elevated markers of inflammation. In conclusion, social isolation was robustly associated with increased inflammation in adulthood, both in medical patients and in the general population. It was associated in particular with systemic chronic inflammation, evident from the consistently stronger associations with suPAR than other inflammation biomarkers.
AB - Social isolation and loneliness have been associated with poor health and increased risk for mortality, and inflammation might explain this link. We used data from the Danish TRIAGE Study of acutely admitted medical patients (N = 6,144, mean age 60 years), and from two population-representative birth cohorts: the New Zealand Dunedin Longitudinal Study (N = 881, age 45) and the UK Environmental Risk (E-Risk) Longitudinal Twin Study (N = 1448, age 18), to investigate associations of social isolation with three markers of systemic inflammation: C-reactive protein (CRP), interleukin-6 (IL-6), and a newer inflammation marker, soluble urokinase plasminogen activator receptor (suPAR), which is thought to index systemic chronic inflammation. In the TRIAGE Study, socially isolated patients (those living alone) had significantly higher median levels of suPAR (but not CRP or IL-6) compared with patients not living by themselves. Social isolation prospectively measured in childhood was longitudinally associated with higher CRP, IL-6, and suPAR levels in adulthood (at age 45 in the Dunedin Study and age 18 in the E-Risk Study), but only suPAR remained associated after controlling for covariates. Dunedin Study participants who reported loneliness at age 38 or age 45 had elevated suPAR at age 45. In contrast, E-Risk Study participants reporting loneliness at age 18 did not show any elevated markers of inflammation. In conclusion, social isolation was robustly associated with increased inflammation in adulthood, both in medical patients and in the general population. It was associated in particular with systemic chronic inflammation, evident from the consistently stronger associations with suPAR than other inflammation biomarkers.
KW - C-reactive protein
KW - Inflammatory biomarkers
KW - Interleukin-6
KW - Loneliness
KW - Social isolation
KW - Soluble urokinase plasminogen activator receptor
KW - Systemic inflammation
U2 - 10.1016/j.bbi.2023.11.022
DO - 10.1016/j.bbi.2023.11.022
M3 - Journal article
C2 - 37992788
AN - SCOPUS:85180007541
VL - 115
SP - 727
EP - 736
JO - Brain, Behavior, and Immunity
JF - Brain, Behavior, and Immunity
SN - 0889-1591
ER -