Biomedical subjects

Roberto Pontremoli

Publications and source records attributed to Roberto Pontremoli.

At least 19 recordsLinked to original sources

PubMed2006

Increased ambulatory arterial stiffness index is associated with target organ damage in primary hypertension.

Increased arterial stiffness has been shown to predict cardiovascular mortality in patients with primary hypertension. Asymptomatic organ damage is known to precede cardiovascular events. We investigated the relationship between a recently proposed index of stiffness derived from ambulatory blood pressure (BP) and target organ damage in 188 untreated patients with primary hypertension. Ambulatory arterial stiffness index was defined as 1 minus the regression slope of diastolic over systolic BP readings obtained from 24-hour recordings. Albuminuria was measured as the albumin:creatinine ratio, left ventricular mass index was assessed by echocardiography, and carotid abnormalities were evaluated by ultrasonography. The prevalence of microalbuminuria, left ventricular hypertrophy (LVH), and carotid abnormalities was 12%, 38%, and 19%, respectively. Ambulatory arterial stiffness index was positively related to age, triglycerides, office and 24-hour systolic BP, 24-hour pulse pressure, urinary albumin excretion, and carotid intima-media thickness. Patients with microalbuminuria, carotid abnormalities, or LVH showed higher ambulatory arterial stiffness index as compared with those without it. After adjusting for confounding factors, each SD increase in ambulatory arterial stiffness index entails an &2 times higher risk of microalbuminuria, carotid abnormalities, and LVH and doubles the risk of the occurrence of >or=1 sign of organ damage. Ambulatory arterial stiffness index is associated with organ damage in patients with primary hypertension. These data strengthen the role of this index as a marker of risk and help to explain the high cardiovascular mortality reported in patients with high ambulatory arterial stiffness index.

Adult↗

PubMed2006

Microalbuminuria and cardiovascular risk assessment in primary hypertension: should threshold levels be revised?

BACKGROUND: Urinary albumin excretion and left ventricular mass are related to each other and to the risk of cardiovascular events in patients with primary hypertension. We aimed to identify a lower threshold for albuminuria that might improve detection of patients with left ventricular hypertrophy (LVH) and cost-effectiveness in cardiovascular risk assessment. METHODS: Albuminuria and left ventricular mass index were assessed in 448 untreated, nondiabetic patients with primary hypertension. The impact that lower albuminuria cut-off levels might have on detecting LVH was evaluated with regard to test cost and sensitivity. This was done by a diagnostic algorithm consisting of albuminuria evaluation followed by echocardiography in the presence of normoalbuminuria. RESULTS: The area under the ROC curve of albuminuria in predicting LVH was 0.73. Using a lower albumin to creatinine ratio threshold than what is recommended by the guidelines (ie, 11.5 mg/g), the sensitivity and specificity of albuminuria in identifying patients with LVH was 39% and 92%, respectively, which translated to positive and negative predictive values of 76% and 69%, respectively. When considering only patients without electrocardiographically detected LVH, routine screening for albuminuria, followed by echocardiography in the presence of albuminuria <or = 11.5 mg/g, allowed us to decrease the number of echocardiograms by 23%. CONCLUSION: Adopting a lower threshold to define microalbuminuria could prove to be cost-effective for assessing cardiovascular risk in hypertensive patients.

Adult↗

PubMed2006

Microalbuminuria, blood pressure load, and systemic vascular permeability in primary hypertension.

BACKGROUND: Microalbuminuria, a powerful predictor of cardiovascular events, is thought to reflect widespread subclinical vascular abnormalities. To explore the pathogenesis of increased urinary albumin excretion in primary hypertension we evaluated systemic capillary permeability and ambulatory blood pressure (BP) measurement in two groups of matched untreated patients with (n = 11) and without (n = 29) microalbuminuria. METHODS: Albuminuria was measured as the mean of albumin-to-creatinine ratio (ACR) in three nonconsecutive first morning urine samples. Systemic capillary permeability was evaluated by transcapillary escape rate of albumin (TERalb) (ie, the 1-h decline rate of intravenous (125)I-albumin). Twenty-four-hour ambulatory BP, renal hemodynamics, and hormones of the renin-angiotensin-aldosterone system (RAAS) were also assessed. RESULTS: Patients with microalbuminuria showed greater body mass index (BMI) (P < .04), higher 24-h systolic and diastolic BP levels (P = .02), and higher capillary permeability to albumin (P < .02) as compared to normoalbuminurics. Renal hemodynamics and RAAS hormones were similar in the two groups. Univariate analysis showed that urinary ACR was related to ambulatory pressure components (P < .02), TERalb (r = 0.31, P < .05), smoking habits (r = 0.36, P = .02), and left ventricular mass index (LVMI) (r = 0.57, P < .001) among the whole study group. Logistic regression analysis showed that each 1% increment in TERalb or 10 mm Hg increase in systolic BP entailed an almost three times higher risk of having microalbuminuria. CONCLUSIONS: Microalbuminuria is associated with greater systemic BP load and increased vascular permeability in patients with primary hypertension.

Adult↗

PubMed2006

Predicting cardiovascular risk using creatinine clearance and an artificial neural network in primary hypertension.

OBJECTIVE: A slight reduction in estimated creatinine clearance is a predictor of unfavorable outcome in patients with primary hypertension. We evaluated how well an artificial neural network (ANN) can assess cardiovascular risk profile on the basis of estimated creatinine clearance and routine, low-cost clinical data, as compared with thorough clinical work-up, which includes an accurate assessment of target organ damage. METHODS: A group of 404 untreated patients with essential hypertension (250 men, 154 women; mean age, 47 +/- 9 years) were studied. We compared two different approaches that can be used to allocate patients into different risk classes according to the European Society of Hypertension-European Society of Cardiology guidelines: thorough clinical work-up, including cardiac and vascular ultrasound scan and microalbuminuria; and prediction by an ANN on the basis of estimated creatinine clearance and routine clinical data. RESULTS: Thorough evaluation, as recommended by the guidelines, showed that 6% (n = 24) of our patients were at low risk, 20% (n = 81) were at medium risk, 45% (n = 182) were at high risk, and 29% (n = 117) were at very high risk. The ANN approach yielded almost superimposable results (sensitivity, 94%; positive predictive value, 96%; r = 0.95). CONCLUSIONS: An ANN can accurately identify the patient's risk status using low-cost, clinical data and estimated creatinine clearance. These results emphasize the value of even a mild reduction in creatinine clearance for the stratification of cardiovascular risk in primary hypertension.

Adult↗

PubMed2006

Ambulatory arterial stiffness index and renal abnormalities in primary hypertension.

OBJECTIVE: Arterial stiffness is a predictor of cardiovascular mortality in the general population as well as in hypertension and end-stage renal disease. We investigated the relationship between a recently proposed ambulatory blood pressure monitoring-derived index of arterial stiffness and early signs of renal damage in patients with primary hypertension. DESIGN AND SETTING: A total of 168 untreated patients with sustained primary hypertension were studied. Ambulatory arterial stiffness index (AASI) was calculated based on 24-h ambulatory blood pressure readings. Albuminuria was measured as the albumin to creatinine ratio. Creatinine clearance was estimated using the Cockcroft-Gault formula, and the interlobar resistive index was evaluated by renal ultrasound and Doppler examination. RESULTS: AASI was positively related to urinary albumin excretion and resistive index, and was negatively related to estimated creatinine clearance and renal volume to the resistive index ratio. Patients with AASI above the median (i.e. > 0.51) showed a higher prevalence of microalbuminuria and a mild reduction in creatinine clearance. Moreover, patients with microalbuminuria or a mild reduction in creatinine clearance had significantly higher AASI values compared with those without, and the greater the renal involvement, the greater the AASI. After adjusting for several potentially confounding variables, we found that each standard deviation increase in AASI (i.e. 0.16) entails an almost twofold greater risk of renal involvement. CONCLUSION: Increased AASI is independently associated with early signs of renal damage in patients with sustained primary hypertension. These results strengthen the usefulness of AASI and ambulatory blood pressure monitoring in cardiovascular risk assessment.

Adult↗

PubMed2006

Serum uric acid as a risk factor for cardiovascular and renal disease: an old controversy revived.

Hyperuricemia is commonly associated with traditional risk factors such as abnormalities in glucose metabolism, dyslipidemia, and hypertension. Recent studies have revived the controversy over the role of serum uric acid as an independent prognostic factor for cardiovascular mortality. The authors review clinical and experimental evidence concerning the role of serum uric acid in the development of cardiovascular and renal damage. Results of trials suggesting that serum uric acid variations over time may have a prognostic impact are also discussed.

Cardiovascular Diseases↗

PubMed2006

Evaluation of subclinical organ damage for risk assessment and treatment in the hypertensive patient: role of microalbuminuria.

Microalbuminuria, i.e., abnormal urinary excretion of albumin, which is detectable by low cost and widely available tests, is a first-line tool for identifying hypertensive patients who are at higher cardiovascular (CV) risk. Numerous studies have provided evidence that microalbuminuria is a concomitant of cardiac and vascular damage as well as a strong, independent predictor of CV events. An important, emerging issue is that the risk for CV morbidity and mortality is linearly related to urinary albumin excretion and persists well below the currently used cutoff for defining microalbuminuria. Furthermore, late-breaking evidence suggests that a reduction of albuminuria under antihypertensive treatment is paralleled by changes in CV risk. The routine search for target organ damage by means of microalbuminuria could lead to a significant improvement in the evaluation and treatment of patients with primary hypertension.

Albumins↗

PubMed2006

Metabolic syndrome and cardiovascular risk in primary hypertension.

The metabolic syndrome can be found in approximately one third of patients who do not have diabetes but have primary hypertension. Its presence has been associated with a wide range of traditional and nontraditional cardiovascular risk factors and early signs of cardiovascular and renal damage. Moreover, it was emphasized recently that the metabolic syndrome predicts an increased probability of sustaining a cardiovascular event or dying. In the clinical setting of insulin resistance, attention should be paid to the metabolic side effects of antihypertensive drugs; therefore, preference should be given to renin-angiotensin system inhibitors and calcium channel blockers rather than to beta blockers and diuretics.

Antihypertensive Agents↗

PubMed2005

Serum uric acid and target organ damage in primary hypertension.

The role of serum uric acid as an independent risk factor for cardiovascular and renal morbidity is controversial. A better understanding of its relationship with preclinical organ damage may help clarify the mechanism(s) implicated in the development of early cardiovascular disease. We evaluated the association between uric acid and the presence and degree of target organ damage in 425 (265 males, 160 females) middle-aged, untreated patients with essential hypertension. Left ventricular mass index and carotid intima-media thickness were assessed by ultrasound scan. Albuminuria was measured as the albumin to creatinine ratio in 3 nonconsecutive first morning urine samples. Overall, patients with target organ damage had significantly higher levels of serum uric acid as compared with those without it (presence versus absence of left ventricular hypertrophy, P=0.04; carotid abnormalities, P<0.05; microalbuminuria, P<0.004; and at least 1 versus no organ damage, P<0.03). In women, the occurrence and severity of each target organ damage we examined increased progressively from the lower to the upper serum uric acid tertiles (P<0.01). After adjustment for body mass index, age, creatinine clearance, and high-density lipoprotein cholesterol, each standard deviation increase in serum uric acid entailed a 75% higher risk of having cardiac hypertrophy and a 2-times greater risk of having carotid abnormalities. These results support the role of serum uric acid as an independent, modifiable marker of cardiovascular damage.

Adult↗

PubMed2005

Mild renal dysfunction and renal vascular resistance in primary hypertension.

BACKGROUND: Mild renal dysfunction (MRD) is an often overlooked but relatively common condition in patients with primary hypertension (PH), and is associated with high cardiovascular morbidity and mortality. Whether MRD is also associated with abnormalities in renal vascular resistance is currently unknown. METHODS: Two hundred ninety-one untreated patients with PH were studied. The MRD was defined as a creatinine clearance >or=60 mL/min but <90 mL/min (Cockcroft-Gault formula) or the presence of microalbuminuria. Albuminuria was measured as the albumin-to-creatinine ratio in first morning urine samples. Renal resistive index (RI) was evaluated by ultrasound Doppler of the interlobar arteries. RESULTS: The prevalence of MRD in our cohort was 63%. Patients with MRD were older, had higher mean blood pressure (BP), pulse pressure, and total cholesterol, longer history of hypertension, and were more likely to be men. Renal RI was positively related to female gender, age, systolic BP, pulse pressure, total cholesterol, albuminuria, and to carotid wall thickness and cross-sectional area, whereas it was inversely related to diastolic BP and creatinine clearance. Patients with the highest renal resistance (upper quartile, >or=0.63) showed a greater prevalence of renal dysfunction (P=.0005). After adjusting for age, pulse pressure, and LDL-cholesterol, we found that the risk of MRD increased twofold (P=.04) when renal RI was >or=0.63. CONCLUSIONS: A reduction in creatinine clearance and the presence of microalbuminuria are associated with increased renal vascular impedence, as well as with signs of extrarenal arterial stiffness.

Adult↗

PubMed2005

Use of nifedipine in the treatment of hypertension.

Hypertension is an important modifiable risk factor for cardiovascular disease; its prevention and treatment currently represent major health concerns around the world, especially in western countries. Effective, well-tolerated drugs such as dihydropyridine calcium channel blockers, to be used either alone or in combination treatments, play a key role in reducing cardiovascular morbidity and mortality. The extended-release formulation of nifedipine given once daily provides a relatively constant concentration profile and has proved to be effective in reducing blood pressure values. In the International Nifedipine gastrointestinal therapeutic system Study: Intervention as a Goal in Hypertension Treatment (INSIGHT) study, it was demonstrated that nifedipine confers cardiovascular protection as effectively as diuretics in high-risk patients, with a smaller incidence of adverse metabolic consequences. Furthermore, two INSIGHT substudies demonstrated that nifedipine prevents the progression of carotid atherosclerosis and reduces the worsening of coronary calcifications, supporting the use of calcium channel blockers in hypertensive patients--especially those at high cardiovascular risk. This review discusses the existing clinical evidence supporting the use of nifedipine in the treatment of hypertension.

Antihypertensive Agents↗

PubMed2005

Role of microalbuminuria in the assessment of cardiovascular risk in essential hypertension.

Accurate cardiovascular risk evaluation is a prerequisite for devising cost-effective therapeutic strategies in patients with essential hypertension. In fact, the knowledge of concomitant risk factors, diabetes, target organ damage, or associated clinical conditions may be useful when deciding both treatment and BP goals. Thorough evaluation of target organ damage is the key to sensitive assessment of global risk, but cost-effective allocation of economic resources should also be taken into consideration. Thanks to its low cost and widespread availability, the search for microalbuminuria is a first-line tool for identifying hypertensive patients who are at higher cardiovascular risk.

Albuminuria↗

PubMed2005

Impact of target organ damage assessment in the evaluation of global risk in patients with essential hypertension.

Accurate assessment of cardiovascular risk is a key step toward optimizing the treatment of hypertensive patients. We analyzed the impact and cost-effectiveness of routine, thorough assessment of target organ damage (TOD) in evaluating risk profile in hypertension. A total of 380 never-treated patients with essential hypertension underwent routine work-up plus evaluation of albuminuria and ultrasonography of cardiac and vascular structures. The impact of these tests on risk stratification, as indicated by European Society of Hypertension-European Society of Cardiology guidelines, was assessed in light of their cost and sensitivity. The combined use of all of these tests greatly improved the detection of TOD, therefore leading to the identification of a higher percentage of patients who were at high/very high risk, as compared with those who were detected by routine clinical work-up (73% instead of 42%; P < 0.0001). Different signs of TOD only partly cluster within the same subgroup of patients; thus, all three tests should be performed to maximize the sensitivity of the evaluation process. The diagnostic algorithm yielding the lowest cost per detected case of TOD is the search for microalbuminuria, followed by echocardiography and then carotid ultrasonography. Adopting lower cut-off values to define microalbuminuria allows us to optimize further the cost-effectiveness of diagnostic algorithms. In conclusion, because of its low cost and widespread availability, measuring albuminuria is an attractive and cost-effective screening test that is especially suitable as the first step in the large-scale diagnostic work-up of hypertensive patients.

Albuminuria↗

PubMed2004

Optimizing global risk evaluation in primary hypertension: the role of microalbuminuria and cardiovascular ultrasonography.

OBJECTIVE: To assess the impact and cost-effectiveness of microalbuminuria and cardiovascular ultrasonography in evaluating the risk profile in primary hypertension. METHODS: Four hundred and five untreated patients with primary hypertension underwent a routine, traditional work-up plus evaluation of albuminuria and ultrasound (US) assessment of cardiac and vascular structures. Albuminuria was measured as the albumin to creatinine ratio in three non-consecutive first-morning urine samples. Left ventricular mass index was assessed by MB-mode echocardiography and carotid intima-media thickness by high-resolution US scan. The impact of these tests on patient risk classes, as indicated by European Society of Hypertension-European Society of Cardiology (ESH-ESC) guidelines, was assessed with respect to their cost and sensitivity. RESULTS: The prevalence of microalbuminuria, left ventricular hypertrophy and carotid intima-media thickening or carotid plaque was 13, 49 and 32%, respectively. The combined use of albuminuria, cardiac and vascular ultrasonography led to the detection of a significantly higher percentage of patients at high/very high risk. The three tests differ in sensitivity (albuminuria, 20%; echocardiography, 65%; and carotid ultrasound, 41%). The signs of target organ damage (TOD) only partly cluster within the same subgroup of patients and, thus, all three tests should be performed in order to maximize the sensitivity of the evaluation process. The diagnostic algorithm yielding the lowest cost per detected case of TOD is the search for microalbuminuria followed by cardiac and carotid ultrasound assessment. CONCLUSIONS: Ultrasonographic detection of TOD is a sensitive tool in the identification of high-risk patients, but should be preceded by a routine search for microalbuminuria in order to optimize the cost-effectiveness of the diagnostic work-up.

Adult↗

PubMed2004

Mild renal dysfunction and cardiovascular risk in hypertensive patients.

Mild renal dysfunction, defined as GFR <60 to 70 ml/min and/or the presence of increased urinary albumin excretion, is associated with higher cardiovascular morbidity and mortality in primary hypertension. The aim of the present study was to investigate the relationship between renal dysfunction and target organ damage (TOD), namely left ventricular hypertrophy (LVH), retinal vascular changes, and carotid atherosclerosis, in a large cohort of unselected middle-aged hypertensive patients with normal serum creatinine. A group of 934 untreated patients with primary hypertension (543 men, 391 women; mean age 50 +/- 11 yr) was studied. Renal function was estimated by the creatinine clearance using the Cockcroft-Gault formula and by the presence of albuminuria, measured as the albumin to creatinine ratio (A/C) in first morning urine samples. LVH was determined according to electrocardiographic criteria, and retinal vascular changes were evaluated by direct ophthalmoscopy in all patients. In a subgroup of patients (n = 340; 208 men, 132 women; mean age 47 +/- 9), the presence and extent of cardiac and vascular organ damage was also assessed by ultrasound techniques. Creatinine clearance was on the average 82 +/- 20 ml/min. The overall prevalence of ECG-detected LVH and retinopathy was 12 and 49%, respectively. Creatinine clearance was inversely related to duration of disease, systolic BP, serum glucose, total cholesterol, LDL cholesterol, and early signs of TOD, namely retinal vascular changes and LVH. Patients in the bottom quintile of creatinine clearance showed higher prevalence of both ECG-determined LVH (P = 0.04) and retinal vascular changes (P = 0.02). In the subgroup of patients who underwent ultrasound evaluation of cardiovascular structures, the prevalence of mild renal dysfunction was 18%, whereas the prevalence of LVH and carotid plaque was 49 and 26%, respectively. Patients with mild renal dysfunction showed higher left ventricular mass and increased intima-media thickness (P < 0.0001), as well as higher prevalence of LVH and carotid plaque as compared with those with normal renal function. Controlling for duration of hypertension and mean BP, the risk of TOD in our cohort increased by 20% for each 10 ml/min decrease in creatinine clearance and by 30% for each 0.2 mg/mmol increase in Log A/C. In conclusion, mild renal dysfunction is associated with preclinical end-organ damage in patients with primary hypertension. These data may help to explain the observed increase in cardiovascular mortality reported in these patients. The evaluation of creatinine clearance and urinary albumin excretion could be useful for identifying patients who are at higher cardiovascular risk.

Cardiovascular Diseases↗

PubMed2004

Cardiovascular and renal risk assessment as a guide for treatment in primary hypertension.

BP levels per se may be an unreliable indicator of risk in the individual patient. In fact, the global cardiovascular profile, including the presence and degree of target organ damage, is a better predictor of future events and, therefore, should be used to choose both treatment and BP goals. However, the prevalence of target organ damage and therefore the percentage of patients who are at risk very much depends on the diagnostic techniques used. However, as a result of the high prevalence of hypertension and its financial impact on public health systems, limiting unnecessary and extensive diagnostic tests also should be a priority. The routine search for microalbuminuria may lead to the detection of a significantly greater percentage of patients who are at high risk while contributing the optimization of the cost-effectiveness of diagnostic workup in hypertensive patients.

Albuminuria↗

PubMed2003

Mild renal dysfunction and subclinical cardiovascular damage in primary hypertension.

The presence of mild renal dysfunction is associated with high cardiovascular morbidity and mortality rates in patients with primary hypertension. The pathophysiological mechanisms underlying this association are currently unknown. We investigated the relation between mild renal dysfunction and subclinical cardiovascular organ damage in 358 never previously treated patients with primary hypertension. Mild renal dysfunction was defined as a creatinine clearance <60 mL/min and/or the presence of microalbuminuria. Left ventricular mass index and carotid intima-media thickness were assessed by ultrasound scan. The prevalence of mild renal dysfunction, left ventricular hypertrophy, and carotid plaque was 18%, 48%, and 28%, respectively. Mild renal dysfunction was related to the presence of several risk factors, such as older age, higher blood pressure levels and lipid status, and smoking habits. Patients with the highest left ventricular mass and carotid intima-media thickness (upper quartiles) showed a higher prevalence of mild renal dysfunction (P<0.0001). After adjusting for duration of hypertension, mean blood pressure, smoking habits, and age, we found that the risk of left ventricular hypertrophy and/or carotid atherosclerosis increased by 43% with each SD reduction in creatinine clearance, and by 89% with each SD increase in albuminuria. Mild renal dysfunction is associated with preclinical end-organ damage in patients with primary hypertension. These data may help explain the high cardiovascular mortality rates reported in patients with low glomerular filtration rate or with increased albuminuria. The evaluation of creatinine clearance and urinary albumin excretion could be useful for identifying subjects at higher cardiovascular risk.

Albuminuria↗

PubMed2003

[High-risk hypertension].

Arterial hypertension is the main risk factor for cardiovascular diseases in western countries and its prevalence, currently around 25% in the general population, is on the rise. Prevention and treatment of high blood pressure and its acute and chronic complications represent a public health priority, due to the relevance of its economic and social consequences. Unfortunately, recent epidemiological surveys indicate that too many patients are either unaware of their condition or are not receiving adequate treatment, in spite of the availability of a large armamentarium of antihypertensive agents which, when used in proper combination, enables the physician to lower blood pressure in virtually all patients. Perhaps more importantly, today it is possible to identify, among the large number of hypertensive patients, those at higher absolute risk for complications. To this end, beside considering the severity of blood pressure load, one should always accurately evaluate the presence of other risk factors and subclinical end-organ damage at the cardiovascular and renal level. This approach is useful in tailoring treatment to each patients' characteristics and leads to the optimisation of its cost/benefit ratio.

Albuminuria↗