The Effect of Serum Magnesium Level on Stable Anticoagulation in Patients Using Warfarin for Various Cardiac Indications

Warfarin is a vitamin K antagonist agent that inhibits clotting factors used for long-term anticoagulation. Time in therapeutic range (TTR) in patients using warfarin is one of the primary treatment effectiveness requirements. We aim to investigate the relationship between serum magnesium levels, the international normalized ratio (INR) values, and TTR values in people using warfarin for various indications. Our study is a single-center, cross-sectional, and retrospective study that included 169 patients between 18 and 70 who used warfarin for various indications. Demographic data, biochemical analysis, and coagulation parameters, including TTR calculation, were evaluated for all patients. Those with a TTR value below 60 were defined as labile INR, and those with 60 and above as stable INR group and compared. The mean INR value was higher in the labile INR group than the stable INR group (3.7 ± 2.9, 3.2 ± 0.3, respectively; p = 0.030). The Mg values are significantly lower in the labile INR group than the stable group (1.8 ± 0.2 mg/dL, 2.0 ± 0.1 mg/dL, respectively; p < 0.001). In binary multivariate logistic regression analysis, magnesium value was the most influential INR stabilization factor ( p < 0.001). As a result of our study, it was concluded that magnesium levels are an influential factor in stabilizing INR. We can state that we have contributed to the literature and can be a reference for future studies.