Correlation Between Hemoglobin Levels and Severity of Coronary Artery Disease in Patients With Myocardial Infarction

Background Coronary artery disease (CAD) is one of the major causes of mortality around the globe. This study aimed to determine the relationship between hemoglobin (Hb) levels and CAD severity in patients with myocardial infarction (MI). Methodology This retrospective study was conducted among 265 MI patients at Jinnah Hospital's Cardiology Unit, Lahore, Pakistan, between March 2022 and March 2023. Consecutive sampling and predefined criteria guided patient enrollment. A predefined proforma collected patient data from the medical record, which was then categorized into non-severe CAD and severe CAD groups based on Gensini scores. Independent t-tests and chi-square tests were used to compare variables between the groups. Pearson's correlation coefficient determined the Hb level and CAD severity relationship, while linear regression analysis assessed the Hb level's predictive value for CAD severity. A p-value <0.05 indicated statistical significance. Data analysis was performed using SPSS software, version 25 (Released 2017; IBM Corp., Armonk, NY, USA). Results Of 265 patients, 170 (64.15%) had non-severe CAD and 95 (35.85%) had severe CAD. The frequency of anemia was also high (n = 142, 53.58%) in the study population. Patients with severe CAD had significantly lower Hb levels (10.12 ± 3.42 g/dL) compared to those with non-severe CAD (12.89 ± 1.90 g/dL). Significant differences were noted in Gensini scores (p < 0.001) and Hb levels (p < 0.001) between the study groups. A strong negative correlation was noted between Hb levels and CAD severity (r = -0.72, 95% confidence interval (CI) = -0.76 to -0.70, p = 0.001). Regression analysis validated Hb level as a significant determinant of CAD severity (negative unstandardized coefficient = -3.10, standardized coefficient = -0.72, 95% CI = -4.90 to -1.50, p = 0.001, R² = 0.46). Conclusions This study presented a significant inverse association between Hb levels and CAD severity in MI patients. Lower Hb levels were correlated with more severe CAD, suggesting its potential as a risk marker and clinical instrument for identifying high-risk patients, facilitating prompt interventions, and guiding therapy.