Association Between C-Reactive Protein and Suicidal Ideation: A Large-Scale Cross-Sectional Study

Studies of C-reactive protein (CRP) levels and suicidal behaviours have shown inconsistent results previously. This study investigated the relationship between CRP levels and suicidal ideation in a large population-based cohort in Korea to enhance the understanding of the biological aspects of suicide and inform more accurate risk assessment models in clinical applications. A multivariate regression model was used to estimate the CRP levels by suicidal ideation and calculate the odds ratio (OR) for suicidal ideation per increase in CRP. People with suicidal ideation had higher CRP levels than those without suicidal ideation (1.35 mg/dL vs. 1.17 mg/dL). In the age- and gender-adjusted model, the OR for suicidal ideation per 1-SD increase in log (CRP) was 1.14 (p = 0.029). However, the fully adjusted model did not reach statistical significance. The relationship between CRP levels and suicide might not be evident among Korean adults. Key Words: C-reactive protein, Inflammation, Socioeconomic factors, Suicidal ideation, Public health problem.