The prevalence of microalbuminuria and its relationship with several cardiovascular risk factors and target organ damage were evaluated in a cohort of 787 untreated patients with essential hypertension. Albuminuria was measured as the albumin-to-creatinine ratio in three nonconsecutive, first morning urine samples. The prevalence of microalbuminuria was 6.7%. Albuminuric patients were more likely to be men and to be characterized by higher blood pressure, body mass index, and uric acid levels and lower HDL cholesterol and HDL cholesterol-to-LDL cholesterol ratio. Piecewise linear regression analysis demonstrated that uric acid and diastolic blood pressure significantly influence albuminuria and together account for a large part of its variations. K-means cluster analysis performed on the entire cohort of patients confirmed that microalbuminuria is associated with a worse cardiovascular risk profile. Furthermore, microalbuminuria was associated with the presence of target organ damage (eg, electrocardiographic [ECG] abnormalities and retinal vascular changes). Age and the presence of microalbuminuria act as independent risk factors for the development of ECG abnormalities and retinal vascular changes. Cluster analysis allowed us to identify three subgroups of patients who differed in the presence or absence of microalbuminuria, retinopathy, and ECG abnormalities. We conclude that the prevalence of microalbuminuria in essential hypertension is lower than previously reported. Increased urinary albumin excretion is associated with a worse cardiovascular risk profile and is a concomitant indicator of early target organ damage.

In patients with CKD, LVH is a strong predictor of the risk of poor CV and renal outcomes independent from LV geometry.

Arterial hypertension together with proteinuria is one of the most important factors associated with the progression of both diabetic and nondiabetic chronic kidney disease. In this review, the role of hypertension and proteinuria in renal disease progression, the BP target that should be achieved to slow the progression of renal damage, and the influence of baseline and current proteinuria on the renoprotective effects of antihypertensive therapy are discussed thoroughly. The interaction between the renoprotective effects of specific antihypertensive agents-mostly angiotensin-converting enzyme inhibitors and angiotensin receptor blockers-and the level of achieved BP also are evaluated. The body of evidence provided by several studies emphasizes the importance of both lowering BP and inhibiting the renin-angiotensin system as specific goals for renal and cardiovascular protection in chronic kidney disease.J Am Soc Nephrol 17: S98 -S103, 2006S98 -S103, . doi: 10.1681 C hronic kidney disease (CKD) is a worldwide public health problem. In the United States, there is an increasing incidence and prevalence of renal failure with poor outcome and high costs and an even higher prevalence of earlier stages of CKD (approximately 80 times greater than ESRD prevalence). Moreover, CKD is associated with elevated cardiovascular morbidity and mortality (1). Therefore, strategies that are aimed at identifying, preventing, and treating CKD and its related risk factors are needed.In the following sections, we focus on the role of hypertension and proteinuria as both independent and interdependent risk factors for renal disease progression. We also discuss BP targets that should be achieved to slow the progression of renal damage, the influence of baseline and current proteinuria on the renoprotective effects of antihypertensive therapy, and the interaction between the renoprotective action of specific antihypertensive agents-mostly angiotensin-converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB)-and the level of achieved BP. Role of Hypertension and Proteinuria on the Progression of Renal DiseaseHigh BP can be either a cause or a consequence of CKD. High BP may develop early in the course of CKD and can be associated with adverse outcomes such as worsening renal function and development of cardiovascular disease. Hypertension is a major promoter of the decline in GFR in both diabetic and nondiabetic kidney disease (2,3). Furthermore, large, observational, prospective trials in the general population showed that hypertension is a strong independent risk factor for ESRD. A strong relationship was observed between both systolic (SBP) and diastolic BP (DBP) and ESRD, regardless of other known risk factors, in men who were recruited in the Multiple Risk Factor Intervention Trial. The relative risk (RR) for ESRD was Ͼ20-fold higher for patients with stage 4 hypertension (SBP Ͼ 210 mmHg or DBP Ͼ 120 mmHg) than for patients with optimal BP levels (SBP Ͻ 120 mmHg and DBP Ͻ 80 mmHg) (4). The recent study by the Oki...

Hypertensive patients with microalbuminuria show a higher prevalence of unfavourable left ventricular geometric patterns, depressed left ventricular function and early signs of extra-cardiac vascular damage. These findings strengthen the role of microalbuminuria as an indicator of subclinical cardiovascular disease and may account for the worse outcome that is usually associated with increased urinary albumin excretion in essential hypertension.

Microalbuminuria has been associated with a cluster of metabolic and nonmetabolic risk factors, suggesting that it might indicate the presence of generalized microvascular damage in patients with essential hypertension. To explore whether microalbuminuria is associated with early target organ damage, two groups of essential hypertensive patients, with (n = 17) (HtAlb+) and without (n = 16) (HtAlb-) microalbuminuria, and a control group (C) of healthy normotensive subjects (n = 20) were studied. The study groups, selected among participants of a large epidemiologic trial, were carefully matched for several potentially confounding variables such as gender, age, duration of hypertension, and body mass index. Albumin excretion rate was evaluated by radioimmunoassay in three nonconsecutive timed overnight collections after 3 weeks of pharmacologic wash-out. Left ventricular mass was assessed by M-B-mode echocardiography, carotid wall thickness by a high resolution ultrasound scan, and renal vascular impedance by Doppler scan. Office as well as 24-h ambulatory pressure monitoring (Takeda TM-2420) were also evaluated. There was no difference between the two hypertensive groups for office and 24-h blood pressure levels except for a lower daytime/nighttime systolic blood pressure ratio in the group with microalbuminuria. Microalbuminuric patients showed signs of early organ damage as compared to normoalbuminuric patients and normal subjects, namely greater left ventricular mass indices (LVMI 167+/-7 g/m2 in HtAlb+; 139+/-9 g/m2 in HtAlb-; 118+/-5 g/m2 in C, P < .001) and increased wall thickness of common carotid arteries (intima plus media thickness 12.5+/-0.2 mm in HtAlb+; 11.7+/-0.3 mm in HtAlb-; 11.2+/-0.2 mm in C, P < .001) as well as higher intrarenal vascular resistance (mean resistive index 0.62+/-0.01 in HtAlb+; 0.59+/-0.01 in HtAlb-; 0.59+/-0.01 in C, P < .05). In conclusion, microalbuminuria is an early marker of diffuse target organ damage in essential hypertension and therefore can be useful to identify patients for whom more aggressive preventive strategies or additional treatment measures are advisable.

ABSTRACT. Microalbuminuria is defined as abnormal urinary excretion of albumin between 30 and 300 mg/d. It can be measured accurately by several widely available and sensitive methods. This abnormality can be found in 8 to 15% of nondiabetic patients with primary hypertension, although its prevalence varies greatly in the literature, likely due to differences in the methods used to detect it and to the criteria applied in the selection of patients. The pathogenetic mechanisms leading to the development of microalbuminuria are still not completely known. BP load and increased systemic vascular permeability, possibly due to early endothelial damage, seem to play a major role. Increased urinary albumin excretion has been associated with several unfavorable metabolic and nonmetabolic risk factors and subclinical hypertensive organ damage. In fact, a higher prevalence of concentric left ventricular hypertrophy and subclinical impairment of left ventricular performance, as well as the presence of carotid atherosclerosis, have been reported in patients with microalbuminuria. These associations might per se justify a greater incidence of cardiovascular events. Long-term longitudinal studies have recently confirmed the unfavorable prognostic significance of microalbuminuria in hypertensive patients. It has also been hypothesized that microalbuminuria might be a forerunner of overt renal damage in primary hypertension. Clinical studies, however, have shown conflicting results, and this hypothesis has to be considered tempting but speculative at present. In conclusion, microalbuminuria is a specific, integrated marker of cardiovascular risk and target organ damage in primary hypertension and one that is suitable for identifying patients at higher global risk. A wider use of this test in the diagnostic work-up of hypertensive patients is recommended. E-mail; rpontrem@medicina.unige.it

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Increased urine albumin excretion is associated with an unfavourable cardiovascular risk profile and prognosis in primary hypertension, even though its pathogenesis is currently unknown. Microalbuminuria (Mi) has been proposed as an integrated marker to identify patients with subclinical organ damage, but its routine use is still too often neglected in clinical practice. The aim of our study was to evaluate the relationship between urinary albumin excretion and early signs of subclinical target organ damage (TOD), namely left ventricular hypertrophy and carotid atherosclerosis in a large group of non diabetic hypertensive patients. A group of 346 never treated patients with primary hypertension (212 men, 134 women, mean age 47 ± 9 years) referred to our clinic were included in the study. They underwent the following procedures: (1) family and personal medical history and physical examination; (2) clinical blood pressure measurement; (3) routine blood chemistry and urine analysis including determination of urinary albumin excretion (ACR); (4) electrocardiogram; (5) ultrasound evaluation of left ventricular mass (LVMI) and