The Impact of Neutrophil-to-High-Density Lipoprotein Ratio and Serum 25-Hydroxyvitamin D on Ischemic Heart Disease

<b>Background:</b> This study describes the complex association between the neutrophil-to-high-density lipoprotein cholesterol ratio (NHR), 25-hydroxyvitamin D (25(OH)D) levels, and cardiovascular disease (CVD), such as stable ischemic heart disease (IHD), ST elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina (UA). <b>Methods:</b> The serum 25(OH)D concentration and NHR values were analyzed in groups of patients with chronic coronary syndrome (CCS) and acute coronary syndrome (ACS). The severity of coronary artery atherosclerosis was determined using the Coronary Artery Surgery Study (CASS) scale. <b>Results:</b> Significant differences in 25(OH)D and NHR concentrations were observed between CCS and (ACS)/STEMI patients (<i>p</i> < 0.01). Higher 25(OH)D concentrations were associated with the diagnosis of CCS, and higher NHR values with the diagnosis of ACS/STEMI. The NHR threshold for ACS was set at 0.10 (<i>p</i> < 0.001). Patients without significant coronary artery stenosis showed significantly higher 25(OH)D levels and lower NHR values (<i>p</i> < 0.01). <b>Conclusions:</b> The significant correlation between 25(OH)D, HDL, and the NHR suggests that vitamin D, through its influence on inflammatory processes and lipid metabolism, may play a role in the pathogenesis of chronic and acute coronary syndromes. The suggested bidirectional relationship between the NHR and 25(OH)D and the role of the NHR as a predictor of vitamin D levels require further well-designed studies.