Elevated Inflammatory Burden Index Is Association With Increased Sarcopenia: A Population-Based Study

The inflammatory burden index (IBI) is a comprehensive indicator of the inflammatory state of the body and is associated with a variety of chronic diseases. Sarcopenia is a disease characterized by a reduction in skeletal muscle mass, but the association between IBI and sarcopenia is currently unclear.

This study was based on data from the National Health and Nutrition Examination Survey (NHANES) 2015-2018 and included 4523 participants aged 20 years and older. IBI was calculated by the product of C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio (NLR). Sarcopenia was defined by the extremity skeletal muscle mass index (ASM/body mass index [BMI]). The association between IBI and sarcopenia was analyzed using multivariate logistic regression models with nonlinear and subgroup analyses.

The mean age of the participants was 39.9 years, and 52.5% were female. Higher IBI scores were associated with a higher risk of chronic disease. IBI was positively associated with sarcopenia, with the highest IBI group having a 1.94 times greater risk of sarcopenia than the lowest group (95% CI: 1.34-2.81). The natural log transformation of IBI resulted in a 42% increase in risk of sarcopenia for each unit increase (95% CI: 1.08-1.87). Nonlinear analyses showed an inflection point in the association between IBI and sarcopenia at 2.38, with a significant increase in risk before the inflection point and no longer significant after the inflection point. Subgroup analyses showed that this association was consistent across sex, age, diabetes, cardiovascular disease (CVD), and chronic kidney disease (CKD).

There is a positive association between IBI and sarcopenia with nonlinear characteristics. High IBI levels may increase the risk of sarcopenia, suggesting that inflammation may play an important role in sarcopenia, providing a potential target for future interventions.