LONELINESS is associated with an increased risk of cardiovascular disease (CVD) in both the United States and South Korea, with both countries showing a similar 15–16% rise in CVD risk among those reporting loneliness, according to a major international study published in the International Journal of Epidemiology.
The impact of loneliness on health has been increasingly recognised, particularly as a risk factor for cardiovascular disease, but most evidence has come from Western, individualistic societies such as the United States. There has been little research exploring whether this relationship holds in collectivistic cultures, where group cohesion and social interdependence are prioritised. Understanding whether the link between loneliness and heart disease is universal or culturally specific is important for informing clinical practice and public health strategies aimed at reducing CVD risk across diverse populations.
To address this question, researchers analysed data from two large, long-term national studies: the Health and Retirement Study in the United States (13,073 participants aged 25–105) and the Korean Longitudinal Study of Aging (8,311 participants aged 45–97). Over a follow-up period of 12–14 years, participants self-reported loneliness and any new onset of CVD during biennial surveys. After adjusting for social isolation, sociodemographic factors, health conditions, and health behaviours, loneliness was associated with a 15% higher risk of CVD in the United States (adjusted hazard ratio [aHR] 1.15, 95% CI 1.04–1.27) and a 16% higher risk in South Korea (aHR 1.16, 95% CI 1.00–1.34). The study also examined the role of health behaviours as mediators of this relationship. In both countries, lower physical activity and higher alcohol consumption partially explained the link between loneliness and CVD, accounting for 14.3% and 3.9% of the association in the United States, and 1.3% and 1.3% in South Korea, respectively. Smoking was a mediator only in the United States, accounting for 4.7% of the association.
These findings demonstrate that loneliness is a significant and universal risk factor for cardiovascular disease, regardless of cultural background. For clinical practice, this highlights the importance of routinely assessing and addressing loneliness alongside traditional cardiovascular risk factors. Interventions to promote social connection and engagement may help reduce CVD risk, while culturally tailored strategies that consider differences in health behaviours—such as smoking in the United States—could further enhance effectiveness. Future research should explore the long-term impact of loneliness-reducing interventions on cardiovascular outcomes and investigate how best to integrate these approaches into routine care for diverse populations.
Reference
Lee HH et al, Loneliness and cardiovascular disease incidence: two cohorts of older adults in the USA and South Korea. International Journal of Epidemiology. 2025;DOI:10.1093/ije/dyaf050.
