Relationship between serum magnesium levels and glycemic control and insulin resistance.

Objective: The role of magnesium in glucose homeostasis, its effects on glycemic control and the causal relationship between them have been the subject of many studies. In this direction, in our study, we aimed to investigate the relationship between serum magnesium (Mg) levels and hemoglobin A1c (HbA1c) and insulin resistance.

Methods: Based on their HbA1c levels, 305 participants were split into 3 groups: 121 were in the control group, 85 were in the prediabetes group, and 99 were in the diabetes group. Serum magnesium levels were measured in these three groups. The correlation between Mg and fasting plasma glucose, fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) was also investigated. In addition, patients' demographic data, blood pressure, smoking habits and basic biochemical data were also included in the analysis.

Results: There was a significant statistical difference in terms of serum magnesium levels among all the groups (p<0.001). A strong negative correlation was found between serum magnesium levels and HbA1c (r=-0.316, p<0.001). There was also a weak negative relationship between Mg and serum fasting glucose, insulin, and HOMA-IR (r=-0.167 p=0.004, r=-0.167 p=0.003, and r=-0.198 p=0.001, respectively).

Conclusion: We observed a statistically significant negative correlation between serum magnesium levels and HbA1c in our study. According to this finding, it would be useful to assess magnesium levels in patients with high HbA1c levels. However, due to conflicting results among studies investigating the relationship between magnesium, glycemic control and insulin sensitivity with increasing interest, more comprehensive, prospective studies with longer follow-up periods are needed.