Altered vascular structure and wave reflection in hypertensive women with low magnesium levels.
Magnesium has been implicated in the pathogenesis of hypertension, but the role of its intracellular levels in cardiovascular diseases is not clear yet. We investigated the relationships of low concentrations of serum magnesium (sMg) and intracellular Mg (iMg) with clinical and vascular parameters. Thiazide-treated hypertensive women were separated into two groups according to lower (<2.0 mg/dL) or normal (≥2.0 mg/dL) sMg concentrations. The same patients were later divided according to lower (<3.75 mg/dL erythrocytes) and normal (≥3.75 mg/dL erythrocytes) iMg concentrations. Carotid ultrasound, radial applanation, and peripheral arterial tonometry were performed in all patients. Low sMg levels were associated with increased Framingham Risk Score (16% ± 3% vs 11% ± 1%; P = .024), higher systolic (148 ± 7 vs 135 ± 3 mm Hg; P = .049) and diastolic (91 ± 3 vs 84 ± 2 mm Hg; P = .042) blood pressure, and carotid intima-media thickness (0.92 ± 0.09 vs 0.76 ± 0.02 mm; P = .023). Low concentrations of iMg were related to wave reflection parameters such as increased augmentation pressure (20 ± 2 vs 15 ± 1 mm Hg; P = .032) and augmentation index (43% ± 2% vs 33% ± 2%; P = .004). In conclusion, in these diuretic-treated hypertensive women, low sMg was associated with higher blood pressure values, and more intense wave reflection were closely linked to iMg depletion, processes that might contribute to hypertension and other cardiovascular risk factors.