G. Andronico

Influence of metabolic syndrome on hypertension‐related target organ damage

Objectives.  The aim of our study was to analyse, in a wide group of essential hypertensive patients without diabetes mellitus, the influence of metabolic syndrome (MS) (defined according to the criteria laid down in the Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults) on markers of preclinical cardiac, renal and retinal damage.

Value of Home Blood Pressures as Predictor of Target Organ Damage in Mild Arterial Hypertension

Background Home blood pressure measurement has gained increasing importance for the management of hypertensive patients. The aim of our study was to compare levels of clinic (CBP), ambulatory (ABP), and home blood pressure (HBP) measurements, and their relationships with various indexes of target organ damage in I–II grade essential hypertension. Design and methods Thirty-eight essential hypertensives underwent evaluation of clinic, ambulatory and home blood pressures. Each patient recorded HBP for 2 days with a digital BP monitor three times daily, the first time on the same day during which ABP monitoring was simultaneously performed. Moreover, in all subjects electrocardiogram recording, echocardiographic study, microalbuminuria assay and fundus oculi examination were obtained. Results The average HBPs obtained on the first day, in particular systolic values, were quite similar to mean daytime ambulatory BP recorded on the same day. Clinic BP, both systolic and diastolic, showed no significant correlation with left ventricular mass index (LVMI) and with albumin excretion rate (AER), whereas a correlation barely significant was observed with an index of global target organ damage (GTODi), including cardiac, renal and retinal parameters. On the contrary, home blood pressures, especially those recorded on the second day, correlated significantly, and more tightly than clinic BP, with LVMI, AER and GTODi. Conclusions Our study seems to justify the adoption of home BP monitoring in the management of hypertensive patients, as a useful complement to clinical readings, and may provide additional prognostic information.

Relationship between albumin excretion rate and aortic stiffness in untreated essential hypertensive patients.

Objectives.  To evaluate, in a group of nondiabetic essential hypertensive patients with normal renal function, the relationship between albumin excretion rate (AER) and carotid‐femoral pulse wave velocity (PWV), as an index of aortic stiffness.

Insulin-like growth factor 1 and sodium-lithium countertransport in essential hypertension and in hypertensive left ventricular hypertrophy

Objective: The aim of this work was to study the insulin-like growth factor 1 (IGF1), a substance able to promote cell proliferation in vascular smooth muscle, in patients with mild-to-moderate hypertension and to analyse its relationship to sodium—lithium countertransport, a genetic marker of hypertension that is related to cardiovascular complications. Method: We studied 32 hypertensive subjects, some with left ventricular hypertrophy, and 14 healthy subjects. Fasting plasma IGF1 was measured by means of a radioimmunoassay after octadecylsilica chromatography and Na+-Li+ countertransport was determined by the method of Canessa. Results: Hypertensive patients had higher values of both IGF1 and Na+-Li+ countertransport. We found a positive correlation, irrespective of age, between IGF1 and Na+-Li+ countertransport. The patients with left ventricular hypertrophy had significantly higher plasma IGF1 levels than those without left ventricular hypertrophy. Conclusion: Our results confirm a possible role for IGF1 in the cardiovascular complications of hypertension and emphasize its relationship to genetically determined factors.

Sympathetic Activity and Blood Pressure Pattern in Autosomal Dominant Polycystic Kidney Disease Hypertensives

To study the potential role of sympathetic activity in the pathogenesis of arterial hypertension associated with autosomal dominant polycystic kidney disease (ADPKD) and to analyze its relationship with 24-hour blood pressure pattern, plasma catecholamines and 24-hour ambulatory blood pressure monitoring were evaluated in 30 ADPKD hypertensive patients (of which 17 without and 13 with renal failure) and in 50 essential hypertensives. The groups were matched for sex, body mass index, known duration of hypertension, and clinic blood pressure. Plasma catecholamines, determined in resting position, were higher in ADPKD patients without renal failure than in essential hypertensives. Nighttime diastolic blood pressure was higher and the percentage day-night difference in mean blood pressure was lower in hypertensives with ADPKD compared to patients with essential hypertension. Blood pressure was significantly correlated with plasma noradrenaline in ADPKD patients, independently of renal function. No significant differences were observed between ADPKD patients with and without renal failure, with respect to plasma catecholamines, 24-hour daytime and nighttime ambulatory blood pressures and the percentage day-night difference in mean blood pressure.

Plasma Aldosterone and Its Relationships With Left Ventricular Mass in Essential Hypertensive Patients With the Metabolic Syndrome

BACKGROUND The association of aldosterone with the metabolic syndrome (MetS) has not been fully elucidated. The aim of our study was to evaluate the relationships of plasma aldosterone concentration (PAC) with MetS and left ventricular mass (LVM) in nondiabetic Caucasian patients with essential hypertension. METHODS Measurements were taken with the patients off antihypertensive medications. The measurements included 24-h blood pressure (BP) readings, plasma renin activity (PRA) and aldosterone, and an echocardiogram. RESULTS Subjects with MetS (n = 201) had higher age-adjusted PAC (10.2 +/- 5.8 vs. 11.6 +/- 5.9 ng/dl; P = 0.01) and greater age-adjusted LVM indexed for height2.7 (LVMH2.7) (56 +/- 19 vs. 62 +/- 20 g/m2; P = 0.001) than those without MetS (n = 249). The difference in respect of PAC between the two groups was independent of PRA and was attributable mainly to obesity. After adjusting for potential confounders, LVMH2.7 was associated with MetS as a whole (beta = 0.11; P = 0.02) and with body mass index (BMI) (beta = 0.19; P < 0.0001) in the overall population. The latter relationship was attenuated (beta = 0.15; P = 0.001) after further adjustment for PAC. In the MetS group the association of LVMH2.7 with PAC held (beta = 0.19; P = 0.007) in multivariate analyses. In subjects without MetS, this relationship had only borderline statistical significance. CONCLUSIONS Our results suggest that the elevated PAC related to obesity may help to explain the increased LVM observed in association with MetS, and may contribute to enhancing the cardiovascular risk associated with MetS.

Favorable clinical heart and bone effects of anti-thyroid drug therapy in endogenous subclinical hyperthyroidism

Although subclinical hyperthyroidism (SCH) has been associated with increased risk of osteoporosis and cardiac arrhythmias, its treatment is still controversial. This study was designed as a prospective, randomized, intervention, control-study with a 1-year follow-up in order to investigate whether normalization of serum TSH in SCH using methimazole has favorable bone and heart clinical effects. Fourteen patients with endogenous SCH (not Graves’ disease) were enrolled, 7 (5 women/2 men; group T) were treated with methimazole (2.5–7.5 mg/day), and 7 (5 women/2 men; group C) were followed without treatment; 10 healthy subjects were also included in the study as controls. Serum free-T3 (FT3), free-T4 (FT4) and TSH, thyroid echography, bone stiffness index (SI), as measured by heel ultrasonometry, and 24-h electrocardiography monitoring were obtained. SCH patients exhibited higher systolic and diastolic blood pressure than control subjects. They also had a significantly higher number of both ventricular premature beats (VPB) (mean±SEM: 681 ±238 vs 6±2 beats/24 h; p<0.02) and atrial premature beats (APB) (mean±SEM: 495±331 vs 7±2 beats/24 h; p<0.0001), and a lower SI (66±5 vs 96±3; p<0.001). Twelve months after normalization of TSH with the use of methimazole, the number of VPB decreased significantly (947±443 vs 214±109 beats/24 h; p<0.05) while it remained unchanged in untreated SCH patients (414±163 vs 487±152 beats/24 h; p=ns). An insignificant therapy effect was observed as far as APB were concerned (826±660 vs 144±75 beats/24 h; p=ns), however their number increased significantly in the untreated group (463±49 vs 215±46 beats/ 24 h; p<0.05). The SI increased significantly as a result of therapy in group T (64.1 ±4.8 vs 70.0±5.3; p<0.02) and was further reduced in group C at the end of the study (69.1 ±7.3 vs 62.9±7.1; p<0.001 ). No adverse effect was observed in group T. In conclusion, anti-thyroid therapy seems to have favorable bone and heart clinical effects in subjects with endogenous SCH.

Insulin, Sodium-Lithium Countertransport, and Microalbuminuria in Hypertensive Patients

Both microalbuminuria (>0.290 nmol/min [20 microg/min]) and high sodium-lithium countertransport (SLC) in diabetic or hypertensive humans are predictive of overt nephropathy and more aggressive cardiovascular complications, perhaps induced by insulin resistance. To analyze the relationships between microalbuminuria, SLC, microalbuminuria, and insulin in essential hypertension, we studied 90 hypertensive white patients, 25 of whom had microalbuminuria and 32 of whom were healthy. When urine sampling was completed for albuminuria determination, SLC was measured; all patients then underwent standard (75 g) oral glucose load to measure basal (0 minutes) and 2-hour glucose and insulin serum levels. Glucose-insulin ratio was used as insulin sensitivity index (ISI). In both hypertensive patients with normal microalbuminuria and those with pathological microalbuminuria, plasma insulin at 120 minutes was significantly higher than in control subjects. When the patients with pathological microalbuminuria were divided into thirds on the basis of their microalbuminuria, in the lower third, we found statistically significant less fasting insulin and higher basal ISI. SLC was higher in hypertensives than normotensives and, among hypertensives, higher in the subgroup with elevated microalbuminuria. In hypertensives, we found a weak but significant correlation between SLC and microalbuminuria, independent of insulin or ISI. The prevalence of high value of SLC (> or =0.383 mmol x L-1 x h-1) was significantly lower in hypertensives with normal rather than abnormal urinary albumin excretion. Our results indicate that in nondiabetic hypertensive whites, higher microalbuminuria is accompanied by signs of insulin resistance; moreover, a link exists between SLC and microalbuminuria, both predictive of aggressive complications of hypertension.

Relationships Between Ambulatory White Coat Effect and Left Ventricular Mass in Arterial Hypertension

The aim of our study was to analyze, in a group of 296 essential hypertensives, the relationship between left ventricular mass (LVM) and ambulatory white coat effect (WCE); that is the difference between the elevation of the first measurements of ambulatory blood pressure monitoring and the mean daytime pressure. The study population was separated into two groups according to the median of the WCE. The LVM was greater in the groups with higher systolic and diastolic ambulatory WCE. The significant association between ambulatory WCE and LVM was confirmed by the results of multiple regression analysis, suggesting that ambulatory WCE may not be an innocent phenomenon.

Absence of an independent association between serum uric acid and left ventricular mass in Caucasian hypertensive women and men

BACKGROUND AND AIM Experimentally uric acid may induce cardiomyocyte growth and interstitial fibrosis of the heart. However, clinical studies exploring the relationship between serum uric acid (SUA) and left ventricular (LV) mass yielded conflicting results. The aim of our study was to evaluate the relationships between SUA and LV mass in a large group of Caucasian essential hypertensive subjects. METHODS AND RESULTS We enrolled 534 hypertensive patients free of cardiovascular complications and without severe renal insufficiency. In all subjects routine blood chemistry, including SUA determination, echocardiographic examination and 24 h ambulatory blood pressure (BP) monitoring were obtained. In the overall population we observed no significant correlation of SUA with LV mass indexed for height(2.7) (LVMH(2.7)) (r = 0.074). When the same relationship was analysed separately in men and women, we found a statistically significant correlation in female gender (r = 0.27; p < 0.001), but not in males (r = -0.042; p = NS). When we grouped the study population in sex-specific tertiles of SUA, an increase in LVMH(2.7) was observed in the highest tertiles in women (44.5 ± 15.6 vs 47.5 ± 16 vs 55.9 ± 22.2 g/m(2.7); p < 0.001), but not in men. The association between SUA and LVMH(2.7) in women lost statistical significance in multiple regression analyses, after adjustment for age, 24 h systolic BP, body mass index, serum creatinine and other potential confounders. CONCLUSIONS Our findings do not support an independent association between SUA and LV mass in Caucasian men and women with arterial hypertension.