Correlation of serum lactate dehydrogenase, calcium and magnesium levels between healthy individuals and coronary artery disease patients: A case-control study

Background: Coronary artery disease involves complex interactions between myocardial injury markers and mineral homeostasis. Magnesium, a physiological calcium antagonist, is underexplored relative to lactate dehydrogenase in the Indian population. The objective is to compare serum lactate dehydrogenase, calcium, and magnesium levels between coronary artery disease patients and healthy controls, and to evaluate their inter-relationships. Material and Methods: This case-control study enrolled 100 diagnosed coronary artery disease patients and 100 age- and gender-matched healthy controls. Serum lactate dehydrogenase was measured by kinetic method, calcium by orthocresolphthalein complexone method, and magnesium by xylidyl blue method. Statistical analysis used Student t test and Pearson correlation coefficient. Results: Coronary artery disease patients had significantly higher serum calcium (9.94 ± 0.42 versus 9.21 ± 0.38 milligram per decilitre, P less than 0.001) and lactate dehydrogenase (352.8± 68.4 versus 172.6 ± 22.4 units per litre, P less than 0.001), and lower magnesium (1.68 ± 0.24 versus 2.14 ± 0.28 milligram per decilitre, P less than 0.001). Hypomagnesemia was present in all 100 coronary artery disease patients. Significant correlations emerged in the disease group: negative correlation between magnesium and lactate dehydrogenase (r equals -0.586, P less than 0.001) and between calcium and magnesium (r equals -0.624, P less than 0.001). No significant correlations were found in controls. Hypertensive and diabetic patients showed the most severe biochemical abnormalities. Conclusion: Universal hypomagnesemia and its strong correlation with elevated lactate dehydrogenase highlight magnesium deficiency as a critical factor in coronary artery disease. Routine magnesium assessment should be mandatory in all such patients.

Keywords: Coronary artery disease, magnesium, lactate dehydrogenase, calcium, hypomagnesemia, case-control study.