Non-linear association of a novel inflammation-lipid composite marker CRP/HDL with insulin resistance and type 2 diabetes: findings from a comprehensive national cross-sectional study.

BACKGROUND

Chronic low-grade inflammation and dyslipidemia are central to the development of insulin resistance (IR) and type 2 diabetes (T2D). The ratio of high-sensitivity C-reactive protein (hs-CRP) to high-density lipoprotein cholesterol (HDL-C) integrates these factors, potentially serving as a novel biomarker for metabolic risk. However, the combined impact of these markers on the risks of IR and T2D has not been thoroughly examined. This study aims to elucidate the relationship between the hs-CRP/HDL-C ratio and the risks of IR and T2D.

METHODS

The cross-sectional methodology of this investigation is underpinned by data procured from the National Health and Nutrition Examination Survey (NHANES), encompassing a sample of 4,928 individuals from 2015 to 2018. The outcome variables were IR and T2D, as defined by the 2013 guidelines of the American Diabetes Association. To thoroughly investigate the association, a variety of analytical techniques were employed. These included weighted multivariate linear regression, weighted multivariate logistic regression, and restricted cubic spline (RCS) models to capture potential nonlinear associations between the hs-CRP/HDL-C ratio and outcomes. Subgroup analyses were also conducted.

RESULTS

After controlling for multiple potential confounders, the ratio correlates with an escalated likelihood of of IR (OR = 2.46, 95% CI: 1.78, 3.40) and T2D (OR = 2.45, 95% CI: 1.48, 4.05). An inverted U-shaped, nonlinear relationship was identified between the ratio and IR, while a nonlinear association was also observed for T2D. However, the non-linear correlation between this ratio and T2D is more pronounced in individuals with hypertension, female, and non-drinkers.

CONCLUSIONS

The hs-CRP/HDL-C ratio exhibits a postive correlation with IR and T2D. These findings suggest that hs-CRP/HDL-C ratio has the potential to be used as biomarker for assessing IR and T2D risk in clinical settings. These results highlight the significance of keeping the hs-CRP/HDL-C ratio within optimal ranges to promote metabolic health, particularly among high-risk groups.