The role of C-reactive protein:albumin ratio and Neutrophil:lymphocyte ratio in predicting coronary artery disease.

Introduction: Acute coronary syndrome (ACS), one of the most common causes of death worldwide, is a condition characterised by ischaemia and/or infarction due to reduced coronary blood flow. The most prevalent cause of ACS is coronary artery disease. In this study, we aimed to investigate the relationship between blood parameters that we commonly use in the laboratory [C-reactive protein (CRP), albumin, neutrophils and lymphocytes] and coronary artery disease (CAD).
Methods: This retrospective, single-centre study included 100 patients who underwent coronary angiography, with the diagnosis of acute coronary syndrome between January and June 2023, and 106 patients with high clinical suspicion and normal coronary arteries as a control group. The NLR was obtained from the ratio of neutrophils to lymphocytes and the CAR was obtained from the ratio of CRP to albumin. We analysed the relationship between CAD and NLR and CAR according to laboratory findings and demographic characteristics of the patients.
Results: The average age of the study group was 59 ± 10 years. NLR and CAR values were higher in the patient group than the control group (5.2 ± 3.3 vs 2.27 ± 1.2, p = 0.004 and 0.5 ± 0.1 vs 0.097 ± 0.095, respectively, p < 0.001). Albumin ratios were found to be statistically significantly lower in the patient group than the patient group (42.4 ± 4 vs 44 ± 3.3, respectively, p = 0.01). In addition, CAR and NLR showed a significant diagnostic value for CAD in receiver operating characteristic curve analysis (area under the curve: 0.68 ± 0.07, p = 0.003; 0.66 ± 0.09 p ≤ 0.001).
Conclusions: NLR and CAR values, which are important indicators of inflammation, were found to be higher in the patient group. We believe it may be important to monitor these patients more frequently and follow them closely in terms of CAD, especially if the rate is higher in individuals without CAD who come for out-patient clinic check-ups.