INCREASED IONIZED CALCIUM-MAGNESIUM RATIO IN ELDERLY HYPERTENSIVES

Abstract

Objective: Alterations in the metabolism of calcium and the biofactor magnesium can be involved in the pathogenesis of essential hypertension. Serum magnesium concentrations only insufficiently reflect disorders in magnesium handling in humans, as only about 1% of total body magnesium stores are in blood. The calcium and magnesium flux across the external membrane is regulated by a calcium pump (calcium-magnesium-ATPase), calcium and magnesium (TRPM 6 and 7) channels and a sodium magnesium antiport. An increased calcium-magnesium ratio is known to be involved in the development of atherosclerosis. Early onset of this disorders are known in hypertension. Design and method: We present a study in 18 hypertensive elderly concerning ionized magnesium concentrations and ionized calcium-magnesium ratio in blood measured by a Prime Plus apparatus by NOVA Medical, Andover, USA. Results: In 18 elderly hypertensives (9 male/9 female with normal renal function) ionized magnesium was measured 0.55 +/- 0.04 mmol/l (normal range: 0.54 - 0.80 mmol/l). The ionized calcium-magnesium ratio was 2.33 +/- 0.18 (normal range below 2.40)(p< 0.05). Data are means +/- SD. ANOVA was used for statistical evaluation. About 40% of elderly hypertensives showed an significantly increased ratio of ionized calcium and magnesium, which is well known to be a marker for the development of arteriosclerosis. Conclusions: As described earlier, a deficiency in the biofactor magnesium can be involved in the pathogenesis of essential hypertension. Ionized magnesium data, as presented here, are rare, but ionized magnesium is the active magnesium in the body regulating about 600 enzymatic reactions. The significantly increased ratio of ionized calcium and magnesium is important in the development of arteriosclerosis often resulting in stroke or heart insufficiency in hypertension.