Increased thickness of the carotid artery in patients with essential hypertension and microalbuminuria.

In patients with essential hypertension, the presence of microalbuminuria carries an increased risk for cardiovascular morbidity and mortality. The mechanisms responsible for this association are not clear. Microalbuminuria could signal the presence of generalised atherosclerosis. To determine the extent of atherosclerosis, we measured by B-mode ultrasound imaging the thickness of the intima and media layers of the carotid artery in 30 hypertensive patients with microalbuminuria, 30 patients without microalbuminuria and 30 normotensive healthy subjects. In hypertensive patients with microalbuminuria, urinary albumin excretion (55 +/- 4.7 mg/24 h) was greater (P < 0.01) than in patients without microalbuminuria (12 +/- 0.9 mg/24 h) and in healthy subjects (7.1 +/- 0.52 mg/24 h). In hypertensive patients with microalbuminuria, the thickness of the carotid artery (0.78 +/- 0.02 mm) was greater (P < 0.01) than in patients without microalbuminuria (0.69 +/- 0.01 mm) and in healthy subjects (0.64 +/- 0.02 mm). In hypertensive patients with microalbuminuria, the mean insulin area-under-the curve (59,703 +/- 4,874 pmol/L x 2 h) and glucose area-under-the curve (928 +/- 40.0 mmol/L x 2 h) were significantly greater (P < 0.005) than in patients without microalbuminuria (38,774 +/- 4,104 pmol/L x 2 h and 803 +/- 34.7 mmol/L x 2 h, respectively), and in normotensive healthy subjects (27,557 +/- 2563 pmol/L x 2 h and 837 +/- 31.2 mmol/L x 2 h, respectively). Serum levels of total cholesterol, triglycerides and lipoprotein(a) were higher in hypertensives with than in those without microalbuminuria. The thickness of the carotid artery was significantly correlated with microalbuminuria, blood pressure, cholesterol, serum triglycerides and insulin area-under-the curve. In conclusion, this study shows that hypertensive patients with microalbuminuria have an increased thickness of the carotid intima and media layers suggesting a greater degree of atherosclerosis. Measurements of urinary albumin excretion may be important in the evaluation of patients with essential hypertension.