Serum magnesium status during lipid-lowering drug treatment in non-insulin-dependent diabetic patients

Serum magnesium concentration (S-Mg) has been reported to be inversely asso ciated with atherogenic lipid fractions and with blood glucose concentratio ns. In some studies on humans, oral magnesium supplementation has been foun d to improve the lipoprotein balance. Against this background the present s tudy was undertaken to determine whether reductions in atherogenic lipid fr actions are associated with S-Mg alterations. Total S-Mg was measured in 23 patients with non-insulin-dependent diabetes mellitus (NIDDM) treated with the lipid-lowering drugs gemfibrozil and simvastatin in a double-blind cro ss-over study. The mean S-Mg at the end of the initial placebo period, ie, before active treatment, was 0.80 (SD 0.06) mmol/L. Treatment with gemfibro zil 600 mg twice daily for 4 months decreased S-Mg by 0.02 mmol/L (P = .02) , and treatment with simvastatin 10 mg daily for 4 months again decreased S -Mg by 0.02 mmol/L (P = .10; not significant [NS]) The changes in S-Mg duri ng the 2 different treatment periods were closely correlated (r = 0.66, P < .001). Fasting plasma glucose concentrations increased significantly by 17 % during both drug regimens. The changes in fasting plasma glucose and S-Mg were significantly correlated both during gemfibrozil treatment (r = -0.56 , P < .01) and during treatment with simvastatin (r = -0.44, P < .05). Chan ges in glucose tolerance or insulin sensitivity did not correlate to change s in S-Mg. The associations between changes in serum very-low-density lipop rotein (VLDL) fractions and S-Mg did not reach statistical significance (r = -0.37, P < .10). Changes in low-density lipoprotein (LDL) cholesterol and S-Mg did not correlate. In conclusion, total S-Mg concentration decreased during treatment with gemfibrozil and simvastatin in patients with NIDDM. D uring both drug regimens changes in S-Mg status were inversely correlated t o changes in plasma glucose concentrations, while changes in lipid status w ere not significantly correlated with changes in S-Mg. Copyright (C) 2001 b y W.B. Saunders Company.