Relationships Between Loneliness, Common Mental Disorders, and Lifetime Suicidality in a Korean Adult Population

Objective Loneliness has emerged as a significant public health concern in Korea. Recent studies suggest that loneliness may be closely associated with common mental disorders (CMDs) and suicidal thoughts and behaviors. This study evaluated associations between loneliness, CMDs, and suicidality among Korean adults.Methods Data were obtained from 704 individuals aged 18–79 years who participated in the Jeju Special Self-Governing Province Mental Health Survey 2023. Loneliness, CMDs, and lifetime suicidality were assessed using a structured interview (the Korean Composite International Diagnostic Interview) and standardized scales (Loneliness and Social Isolation Scale).Results High levels of loneliness were associated with CMDs and lifetime suicidality. After adjustment, demographic factors were not independently associated with suicidality, whereas CMDs remained a significant predictor. Loneliness demonstrated an independent association with suicidality and was associated with higher suicidality risk, particularly among individuals with CMDs.Conclusion Loneliness independently contributes to suicide risk beyond the effects of CMDs, emphasizing the importance of public health interventions that address social engagement to prevent suicidal behaviors.