The association between Life’s Crucial 9 (LC9) and low muscle mass (LMM): The mediating role of Dietary Inflammatory Index (DII)

Some studies suggest a potential link between cardiovascular health, inflammation, and low muscle mass (LMM). However, the mechanisms through which inflammation influences the relationship between cardiovascular health and LMM remain unclear. Life's Crucial 9 (LC9) is a recently proposed method for assessing cardiovascular health. In addition, the Dietary Inflammatory Index (DII) is a novel, quantifiable measure of dietary inflammatory potential. This study investigates the relationship between LC9 and LMM and evaluates whether DII moderates this relationship. Subgroup analysis, restricted cubic splines, and multivariable logistic regression were employed to explore the relationship between LC9 and LMM. In addition, mediation analysis was conducted to investigate the potential role of DII in moderating the relationship between LC9 and LMM. Data were obtained from the National Health and Nutrition Examination Survey conducted between 2011 and 2018. A total of 7815 participants were included in this study, with 653 reporting LMM events. After adjusting for all variables using multivariable logistic regression, each 10-unit increase in LC9 was associated with a 53% reduction in LMM prevalence (odds ratio = 0.47, 95% confidence interval = 0.39-0.55), while each 1-unit increase in DII was associated with a 25% increase in LMM prevalence (odds ratio = 1.25, 95% confidence interval = 1.16-1.35). Consistent results were obtained when LC9 and DII were categorized into tertiles, with a P for trend <.001. Restricted cubic splines analysis revealed a linear negative association between LC9 and LMM prevalence. Mediation analysis indicated that 11.10% of the relationship between LC9 and LMM was mediated by DII (P = .002). This study found a significant negative association between LC9 and LMM, with DII partially mediating this relationship. These findings highlight the potential link between cardiovascular health and LMM, underscoring the importance of an anti-inflammatory diet in reducing the prevalence of LMM.