Inflammation markers detected in complete blood count are associated with coronary atherosclerosis and may indicate its severity

Background. Inflammation is crucial in coronary artery disease (CAD) development. As additional markers of inflammation, some complete blood count (CBC) parameters are investigated. Aim. The aim was to assess relationship between CBC readings and CAD severity in stable angina pectoris (SAP) patients. Methods. This retrospective study enrolled 166 patients who met inclusion criteria (no comorbidities other than arterial hypertension, dyslipidaemia) and were treated at Kaunas Clinics Cardiology Department from July 2023 to August 2024. CAD was assessed by coronary angiography (CA) or computed tomographic coronary angiography (CCTA). Patients who underwent CA were divided according to CAD severity by Gensini score: from 0 to 11; 12 to 35; more than 35. According to CAD-RADS score: CAD-RADS 0; CAD-RADS 1 and 2; CAD-RADS 3; CAD-RADS 4 and 5. Systemic inflammatory response index (SIRI) was calculated monocyte-to-lymphocyte ratio (MLR) multiplied by neutrophils, systemic immune-inflammation index (SII) — platelets multiplied by neutrophilto-lymphocyte ratio (NLR). Statistical analysis was performed using Mann–Whitney-U, Kruskal-Wallis, ÷2 tests, Spearman correlation coefficient. Results. The mean age was 61.4 (10.38) years, 57.8% (n = 96) were male. Patients with CAD had lower lymphocyte-to-monocyte ratio (LMR), higher NLR, SIRI, MLR, and SII compared to patients without CAD (p < 0.001; p = 0.01 for SII). According to CAD severity, NLR, MLR, SII, and SIRI values increased and LMR decreased gradually with increasing Gensini score (p < 0.001). LMR decreased (p < 0.046) and SIRI (p < 0.001) increased gradually with increasing CAD-RADS score. SII (r = 0.511, p < 0.001), NLR (r = 0.567, p < 0.001), SIRI (r = 0.474, p < 0.001), MLR (r = 0.356, p 0.001), LMR (r = –0.355, p < 0.001) correlated with severity of CAD according to Gensini score. The CAD-RADS score correlated with NLR (r = 0.365, p < 0.001), LMR (r = –0.454, p 0.001), MLR (r = 0.455, p < 0.001), SIRI (r = 0.522, p < 0.001). Conclusions. NLR, LMR, and SIRI appear to be valuable indicators of inflammation, and SIRI is the best CAD severity predictor in SAP patients of all the other CBC parameters assessed.