Background. Some patients with essential hypertension manifest greater than
normal urinary albumin excretion (UAE). A few retrospective studies have s
uggested that there is an association between microalbuminuria and cardiova
scular risk. The reasons for this association are not well established, and
they are the object of this review.
Results. We found that hypertensive patients with microalbuminuria manifest
greater levels of blood pressure, particularly at night. Serum levels of c
holesterol, triglycerides, and uric acid in patients with microalbuminuria
were higher than levels in those with normal UAE, whereas levels of high-de
nsity lipoprotein cholesterol in patients with microalbuminuria were lower
than levels in patients with normal UAE. Patients with microalbuminuria man
ifest a greater incidence of insulin resistance, and thicker carotid arteri
es. After a follow-up of seven years we observed that 12 cardiovascular eve
nts occurred among 54 (21.3%) patients with microalbuminuria, and only two
such events among 87 patients with normal UAE (P < 0.0002). Stepwise logist
ical regression analysis showed that UAE, cholesterol level and diastolic b
lood pressure were independent predictors of the cardiovascular outcome. Th
e rate of clearance of creatinine from patients with microalbuminuria decre
ased more than did that from those with normal urinary albumin excretion.
Conclusions. These studies suggest that hypertensive individuals with micro
albuminuria manifest a variety of biochemical and hormonal derangements wit
h pathogenic potential, which result in greater incidence of cardiovascular
events and a greater decline in renal function than do patients with norma
l UAE.