Red cell distribution width to albumin ratio (RAR) as a potential biomarker of coronary heart disease (CHD): Insights from a cross-sectional study

While significant evidence has linked various biomarkers to cardiovascular risk, the role of the red cell distribution width to albumin ratio (RAR) in predicting coronary heart disease (CHD) remains underexplored. This cross-sectional study utilized data from 48,928 participants from the National Health and Nutrition Examination Survey (NHANES) 1999 to 2018. The exposure variable was RAR, calculated as the ratio of red cell distribution width to serum albumin levels. CHD was determined based on self-reported data. Multivariate logistic regression was used to examine the relationship between RAR and CHD, adjusting for potential confounders, with stratified analyses by sex, diabetes status, and hypertension status. The mean age of participants was 49.64 ± 18.17 years, with a mean RAR of 3.15 ± 0.51. In the fully adjusted model (Model 3), an increase in RAR was associated with an increased risk of CHD (OR = 1.31, 95% CI: 1.13, 1.51, P < .001). Stratified analysis revealed that higher RAR quartiles were associated with higher CHD risk, especially in females and those with diabetes. But no significant interaction was found between RAR and gender or diabetes status on CHD risk. Our study suggests that RAR is associated with an increased risk of CHD, particularly at higher quartiles. While RAR may help clinicians identify individuals at elevated risk for CHD, further longitudinal studies and mechanistic investigations are needed to better understand its predictive value and clinical applicability.