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The following is a summary of “Inflammatory burden index is correlated with increased depression: a population-based study,” published in the March 2025 issue of BMC Psychiatry by Shao et al. 

Depression is linked to systemic inflammation. The Inflammatory Burden Index (IBI) measures overall inflammatory levels. 

Researchers conducted a prospective study to assess the correlation between IBI and depression in the general population.  

They analyzed National Health and Nutrition Examination Survey (NHANES) data (1999–2018) in a cross-sectional study. IBI was formulated as C-reactive protein × neutrophils/lymphocytes. The correlation between depression prevalence and IBI was explored using multivariate logistic regression, subgroup, interaction, restricted cubic spline (RCS), and sensitivity analyses.

The results showed that 14,557 subjects were included, with 1,231 (8.5%) having depression. Multivariate logistic regression and RCS analyses showed a linear positive correlation between IBI and depression (odds ratio (OR) = 1.03, 95% CI–1.05, P = 0.007). Depression prevalence was higher in the third IBI tertile (40.0%) than in the first (P < 0.001). Stratified analysis confirmed this correlation (all interaction P > 0.05). Sensitivity analyses, excluding the upper and lower 2.5% of IBI, showed a stable correlation (OR = 1.08, 95% CI: 1.01–1.15, P < 0.001). 

Investigators found a positive correlation between IBI and depression in American adults. Further large-scale prospective studies were needed to analyze IBI’s role in depression. 

Source: bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-025-06730-6