Association between C-reactive protein to albumin ratio and subclinical myocardial injury in the general population free from cardiovascular disease

The study aimed to examine the role of the C-reactive protein to albumin ratio (CAR) as an inflammatory biomarker in relation to subclinical myocardial injury (SC-MI), addressing the limited knowledge of their association. The study included 5,949 individuals without cardiovascular disease (CVD) from the National Health and Nutrition Examination Survey. SC-MI was identified through a Cardiac Infarction Injury Score (CIIS) of ≥ 10 units based on a 12-lead electrocardiogram. The study used multivariate logistic regression models, adjusted for potential confounders, to evaluate the relationship between CAR and SC-MI. Subgroup analyses were conducted to substantiate the results, and the non-linear correlation was assessed via restricted cubic spline (RCS) regression. The RCS curve showed a significant positive correlation between CAR and SC-MI (P for nonlinear = 0.2496). When adjusted for all confounders, individuals in the highest tertile of CAR exhibited a higher likelihood of SC-MI compared to those in the lowest tertile, with an odds ratio (OR) of 1.21 (95% CI: 1.06–1.39, P for trend = 0.029). A 10-unit increment in CAR was linked to a 3.6% heightened risk of SC-MI [OR = 1.036 (95% CI: 1.006, 1.066)], with this association being more prominent among male adults, non-smokers, married individuals, those without diabetes mellitus, and those with no history of cancer. The findings of this study suggest a positive correlation between CAR and SC-MI among the US adult population, indicating the potential of CAR in enhancing SC-MI prevention strategies in the general population.