INCREASED IONIZED CALCIUM-MAGNESIUM-RATIO IN ELDERLY HYPERTENSIVES - RELATIONSHIP TO ARTHERIOSCLEROSIS

Abstract

Objective: Changes in calcium and magnesium metabolism are involved in the pathogenesis of primary hypertension. The calcium and magnesium flux across the external membrane is regulated by a calcium pump (calcium-magnesium-ATPase), calcium and magnesium channels (TRPM 6 and 7) and a sodium-magnesium-antiport. An increased calcium-magnesium-ratio is known to be involved in the development of atherosclerosis. Early onset of these disorders are known in hypertension. In earlier animal studies this phenomenon has been described, too. Design and method: Our study was performed in 18 elderly hypertensives (9 male/9 female, with normal renal function, age beyond 60 years). No patient had diabetes mellitus, no diuretic therapy for at least 4 weeks before entry in study and no magnesium supplementation. In each patient ionized calcium and magnesium was measured and the calcium-magnesium-ratio was calculated. Measurements were performed by a Prime Plus Apparatus by NOVA Medical, Rödermark, Germany. Results: Ionized magnesium was measured 0.55 + /-0.04 mmol/L, normal range 0.54–0.80 mmol/L) in patients. The ionized calcium-magnesium-ratio was 2.33+/-0.18 (normal range below 2.40). About 40% of elderly hypertensives showed an increased ratio of ionized calcium and magnesium, which is known to be a marker for the development of artheriosclerosis. Conclusions: As described earlier, a magnesium deficiency can be involved in the pathogenesis of hypertension and in elderly. The increased calcium-magnesium-ratio is also a pathogenetic factor for artheriosclerosis often found in elderly hypertensives with vascular damage, e.g. stroke, renal insufficiency or heart disease.