MICROALBUMINURIA AND ERYTHROCYTE SODIUM-HYDROGEN EXCHANGE IN ESSENTIAL-HYPERTENSION

Microalbuminuria (urinary albumin excretion between 20 and 200 mu g/mi n) and abnormalities of red blood cell sodium-hydrogen exchange coexis t in essential hypertensive patients. To evaluate how the two phenomen a relate, we recruited 10 untreated microalbuminuric male essential hy pertensive patients without diabetes to be compared with an equal numb er of matched essential hypertensive patients excreting albumin in nor mal amounts as well as 10 healthy control subjects. Sodium-hydrogen ex change values were increased to a comparable extent in microalbuminuri c and normoalbuminuric hypertensive patients. Systolic and mean blood pressures were higher in microalbuminuric patients. Fasting insulin wa s greater and high-density lipoprotein cholesterol lower in patients t han control subjects. Urinary albumin excretion correlated positively with both mean blood pressure and left ventricular mass values in the absence of a relationship with circulating lipid and insulin levels. I n contrast with microalbuminuria, sodium-hydrogen exchange covaried on ly with high-density lipoprotein cholesterol and insulin levels. Thus, microalbuminuria and an abnormal sodium-hydrogen exchange are unrelat ed phenomena in essential hypertensive patients. Microalbuminuria appe ars to be a hemodynamically driven biological variable, while an accel erated sodium-hydrogen exchange seems primarily conditioned by the met abolic abnormalities of hypertension, possibly in the context of an in sulin-resistant syndrome.