Verification of the Short-term Effect of SGLT2 Inhibitors on Serum Magnesium Stratified by the Classification of Albuminuria Severity in Patients with Type 2 Diabetes Mellitus

Objective This study aimed to investigate the short-term effect of sodium/glucose cotransporter 2 inhibitors (SGLT2is) on serum magnesium (sMg) across three subgroups stratified according to the severity of albuminuria in patients with type 2 diabetes mellitus (T2DM). Methods Ninety patients were stratified into three subgroups according to their urinary albumin-to-creatinine ratio (UACR) at the initiation of SGLT2i treatment, according to the severity classification of albuminuria: A1 (normoalbuminuria; n=39), A2 (microalbuminuria; n=30), and A3 (macroalbuminuria; n=21). We evaluated the changes in sMg three months after the initiation of SGLT2i treatment in each subgroup. Subsequently, we compared the changes (Δ) in sMg levels across the three subgroups. Additionally, we investigated the baseline parameters correlated with ΔsMg, as well as the changes in parameters associated with ΔsMg. Results sMg was significantly increased in all subgroups (p<0.001 for A1, A2, and A3). ΔsMg was significantly different across the three subgroups (p=0.036), and ΔsMg in A3 was significantly greater than that in A1 (p=0.032). ΔsMg was positively correlated with baseline UACR (β=0.244, p=0.040) and inversely correlated with baseline sMg (β=-0.478, p<0.001). ΔsMg was positively correlated with Δserum albumin level (β=0.239, p=0.033). Conclusion The short-term effect of SGLT2is on sMg levels was more pronounced in T2DM patients with macroalbuminuria.