Ambulatory blood pressure monitoring in the elderly: features and perspectives

Aging leads to a multitude of changes in the cardiovascular system that include a rise in blood pressure. Age-related changes in blood pressure are mainly attributable to an increase in systolic blood pressure, generally associated with a slight decrease diastolic blood pressure. This leads to a widening in pulse pressure. Ambulatory blood pressure monitoring is a useful tool to understand these processes and to refine cardiovascular risk assessment. In the light of emerging data in this area, we reviewed the main features of ambulatory blood pressure in elderly and discussed the evidence showing that ambulatory blood pressure is superior to clinic blood pressure to reflect the true pattern of blood pressure over time. Furthermore, we discussed the role of weight control obtained by fitness programs to prevent an excessive rise in blood pressure with age. A thorough understanding of these concepts is of paramount importance and has therapeutic implications in the growing population of elderly subjects with increased blood pressure.

Validation of a disease-specific health-related quality of life measure in adult Italian patients with systemic lupus erythematosus: LupusQoL-IT

OBJECTIVE

The objective of this paper is to assess the validity of a linguistically validated version of the Lupus Quality of Life (LupusQoL(©)) in Italian patients affected by systemic lupus erythematosus (SLE).

METHODS

Consecutive SLE patients completed the Italian version of the LupusQoL(©) and the Short Form (SF)-36. Disease activity was evaluated by the SLE disease activity Index-2000 (SLEDAI-2 K), and chronic damage by the Systemic Lupus International Collaborating Clinics/American College Rheumatology (ACR) Damage Index score (SDI). Internal consistency and test-retest reliability, convergent and discriminant validity were examined. Factor analysis with varimax rotation was performed.

RESULTS

A total of 117 Italian SLE patients (M:F 13:104; mean age 40.6 ± 11.6 years, mean disease duration 127.5 ± 94.1 months) were recruited into the study. The Italian version of the LupusQoL(©) demonstrated substantial evidence of convergent validity in these patients when compared with equivalent items of the SF-36. In addition, the LupusQoL(©) discriminated between patients with different degrees of disease activity as measured by the SLEDAI-2 K. SLE patients with higher disease activity (SLEDAI-2K ≥4) showed poor QoL compared with those with lower disease activity (SLEDAI-2K <4), with significant differences in the domains of physical health, planning, burden to others and fatigue (p = 0.001, p = 0.04, p = 0.03, p = 0.04, respectively). The confirmatory factor analysis using the eight domain loadings of the 34 items showed a poor fit (χ(2)/degree of freedom (df) 2.26, χ(2 )= 1128.6 (p < 0.001), root mean square error of approximation (RMSEA) = 0.167; goodness-of-fit index (GFI) = 0.606, comparative fit index (CFI) = 0.649)). Screeplot analysis suggested a five-factor loading structure and confirmatory factor analysis result of which is similar to the eight-factor model. A good internal consistency was observed (Cronbach's α 0.89-0.91). Test-retest reliability was good to excellent between baseline and day 15 (intraclass correlation coefficient (ICC) 0.90-0.98).

CONCLUSION

The Italian version of the LupusQoL(©) is a valid tool for adult patients with SLE.

Microalbuminuria and hypertension

An elevated urinary albumin excretion (UAE) below the proteinuric level, i.e. microalbuminuria (MAU), has long been recognized as a marker of kidney disease and increased cardiovascular risk in both types of diabetes mellitus. Subsequent clinical evidence documented an association between MAU and other cardiovascular risk factors, target organ damage and risk of cardiovascular disease in the general population and in specific clinical contexts including essential hypertension. This article reviews the available evidence on the clinical value of MAU in subjects with essential hypertension. In these subjects, the reported prevalence of MAU ranges from about 4% to 46% across different studies and these differences may be explained by the huge intraindividual variability in UAE, age and ethnicity, discrepancies in the technique of measurement and different definitions of MAU. A direct and continuous association between UAE and blood pressure (BP) and left ventricular mass has been found in most studies. In contrast, it is not yet clear whether the association between UAE and other factors including age, gender, smoking, ethnicity, insulin resistance, lipids and obesity is independent or due to confounders, particularly BP. Several prospective studies disclosed an association between MAU and the risk of future cardiovascular disease. Of particular note, in some of these studies the incidence of major cardiovascular events progressively increased with UAE starting below the conventional MAU thresholds. Thus, besides being a direct risk factor for progressive renal damage, MAU can be considered a marker which integrates and reflects the long-term level of activity of several other detrimental factors on cardiovascular system. Antihypertensive treatment reduces UAE and such effect may be detected after just a few days of treatment. Among available antihypertensive drugs, angiotensin converting enzyme (ACE) inhibitors and the angiotensin II receptor antagonists seem to be superior to other antihypertensive drugs in reducing UAE. The dual blockade of the renin angiotensin system with an ACE inhibitor and an angiotensin II receptor antagonist is a new and promising approach to control UAE in hypertensive patients. Determination of MAU is recommended in the initial work-up of subjects with essential hypertension as suggested in the most recent European hypertension guidelines, even though, as upcoming evidence suggest, the periodic evaluation of this simple, inexpensive and predictive marker might be valuable and cost-effective.

Left ventricular mass and systolic dysfunction in essential hypertension

A relation between left ventricular (LV) hypertrophy and depressed midwall systolic function has been described in hypertensive subjects. However, a strong confounding factor in this relation is concentric geometry, which is both a powerful determinant of depressed midwall systolic function and a correlate of LV mass in hypertension. To evaluate the independent contribution of LV mass to depressed systolic function, 1827 patients with never-treated essential hypertension (age 48 +/- 12 years, men 58%) underwent M-mode echocardiography under two-dimensional guidance. Relative wall thickness was the strongest determinant of low midwall fractional shortening (r = -0.63, P < 0.0001). The significant inverse relation observed between LV mass and midwall fractional shortening (r = -0.43, P < 0.0001) persisted after taking into account the effect of relative wall thickness (partial r = -0.27, P < 0.0001). Within each sex-specific quintile of relative wall thickness, prevalence of subnormal afterload-corrected midwall systolic function was greater in subjects with, than in subjects without, LV hypertrophy (P < 0.05 for the first, third, fourth and fifth quintile). In a multiple linear regression analysis, both LV mass (P < 0.0001) and relative wall thickness (P < 0.0001) were independent predictors of a reduced midwall fractional shortening. In conclusion, the inverse association between LV mass and midwall systolic function is partly independent from the effect of relative wall thickness. LV hypertrophy is a determinant of subclinical LV dysfunction independently of the concomitant changes in chamber geometry.

High-density lipoprotein cholesterol and left ventricular hypertrophy in essential hypertension

OBJECTIVE

The proportion of left ventricular (LV) mass variability explained by blood pressure in essential hypertension is small, and several non-haemodynamic determinants of LV mass have been identified or hypothesized. This study examines the possible relation between blood lipids and LV mass in hypertension.

DESIGN

Never-treated non-diabetic hypertensive patients.

SETTING

Hospital hypertension outpatient clinics in Umbria, Italy.

PATIENTS

We investigated the association between high-density lipoprotein (HDL)-cholesterol and echocardiographic LV mass in 1306 never-treated subjects with essential hypertension. Subjects with previous cardiovascular events, diabetes and current or previous antihypertensive or lipid-lowering therapy were excluded.

RESULTS

HDL-cholesterol showed an inverse association with LV mass (r = -0.30, P < 0.001). No association was found between LV mass and total or low-density lipoprotein cholesterol. With multiple linear regression analysis we tested the independent contribution of several potential determinants of LV mass in women and in men. Average 24 h blood pressure (both pulse and mean), body mass index, height, stroke volume, age (all P < 0.01) and low HDL-cholesterol (P < 0.0001 in women, P < 0.001 in men) were associated with a greater LV mass in both sexes. Triglycerides showed a weak univariate association with LV mass in women (r = 0.11, P < 0.02), which did not hold in a multivariate analysis.

CONCLUSIONS

Low HDL-cholesterol is an independent predictor of LV mass in untreated hypertensive subjects. Common hormonal and metabolic mechanisms, including insulin resistance, could explain this association, which may contribute to the adverse prognostic significance of low HDL-cholesterol levels.

Left ventricular hypertrophy as an independent predictor of acute cerebrovascular events in essential hypertension

BACKGROUND

It is uncertain whether left ventricular hypertrophy (LVH) confers an increased risk for cerebrovascular disease in apparently healthy patients with essential hypertension.

METHODS AND RESULTS

A total of 2363 initially untreated hypertensive patients (mean age 51+/-12 years, 47% women) free of previous cardiovascular disease were followed up for up to 14 years (mean 5 years). At entry, all patients underwent diagnostic tests, including ECG, echocardiography, and 24-hour ambulatory blood pressure (BP) monitoring. At entry, the prevalence of LVH was 17.6% by ECG (Perugia score) and 23.7% by echocardiography (LVM >125 g/m(2)). Over the subsequent years, 105 patients experienced a first stroke or transient ischemic attack. The cerebrovascular event rate was higher among patients with LVH at entry, diagnosed by either ECG or echocardiography, than among those without hypertrophy (both P<0.01). After control for the significant influence of age, sex, diabetes, and 24-hour mean ambulatory BP, LVH by ECG conferred an increased risk for cerebrovascular events (relative risk [RR] 1.79; 95% CI 1.17 to 2.76). LVH by echocardiography also conferred a higher risk for cerebrovascular events (RR 1.64; 95% CI 1.07 to 2.68). For each increase in LV mass of 1 SD (29 g/m(2)), there was a significant independent increase in the risk for cerebrovascular events (RR 1.31; 95% CI 1.09 to 1.58).

CONCLUSIONS

In apparently healthy patients with essential hypertension, LVH diagnosed by ECG or echocardiography confers an excess risk for stroke and transient ischemic attack independently of BP and other individual risk factors.

Optimizing assessment of carotid and femoral intima-media thickness in essential hypertension

Large artery intima-media thickness (IMT) is considered an integrated marker for the total individual burden of arteriosclerosis, and a graded index for cardiovascular risk. However, several different aggregate indexes of IMT on B-mode ultrasound have been used by various investigators, and the optimal number of IMT readings is currently unsettled. In 128 newly diagnosed, never treated, uncomplicated hypertensive subjects aged <55 years (43 +/- 9 years, blood pressure [BP] 152/99 mm Hg), we measured left ventricular mass (M-mode echocardiography, average of five or more measurements) and IMT of common carotid and common femoral arteries. For each segment, 12 IMT measurements were performed, and the average of 1 and 3 readings (right far wall), 6 readings (right side), and 12 readings (right and left side, far and near wall, 3 sampling points) was analyzed. The relation of IMT with left ventricular mass increased progressively with increasing number of readings, from 0.35 (1 reading) to 0.51 (12 readings) for common carotid artery, and from 0.31 to 0.56 for common femoral artery (both P <.001). For each 0.2-mm increase in common femoral IMT, the age-adjusted relative risk of having left ventricular hypertrophy was 1.31 for 1 reading, and increased up to 3.59 for the average of 12 readings. In summary, the association of IMT with left ventricular mass depends strongly on the number of IMT readings. The average of several readings in each segment, including right and left side and far and near wall, carries the closest association to left ventricular mass, and should be preferred for clinical purposes in hypertensive subjects.

Short daily hemodialysis: blood pressure control and left ventricular mass reduction in hypertensive hemodialysis patients

Several retrospective and uncontrolled prospective studies reported blood pressure (BP) normalization and left ventricular mass (LVM) reduction during daily hemodialysis (DHD). Conversely, the burden of these major independent risk factors is only marginally reduced by the initiation of standard thrice-weekly dialysis (SHD), and cardiovascular events still represent the most common cause of death in hemodialysis patients. Therefore, we performed a randomized two-period crossover study to compare the effect of short DHD versus SHD on BP and LVM in hypertensive patients with end-stage renal disease. We studied 12 hypertensive patients who had been stable on SHD treatment for more than 6 months. At the end of 6 months of SHD and 6 months of DHD in a sequence of randomly assigned 24-hour ambulatory BP monitoring, echocardiography and bioimpedance were performed. Throughout the study, patients maintained the same Kt/V. A significant reduction in 24-hour BP during DHD was reported (systolic BP [SBP]: DHD, 128 +/- 11.6 mm Hg; SHD, 148 +/- 19.2 mm Hg; P < 0.01; diastolic BP: DHD, 67 +/- 8.3 mm Hg; SHD, 73 +/- 5.4 mm Hg; P = 0.01). The decrease in BP was accompanied by the withdrawal of antihypertensive therapy in 7 of 8 patients during DHD (P < 0.01). LVM index (LVMI) decreased significantly during DHD (DHD, 120.1 +/- 60.4 g/m(2); SHD, 148.7 +/- 59.7 g/m(2); P = 0.01). Extracellular water (ECW) content decreased from 52.7% +/- 11.4% to 47.6% +/- 7.5% (P = 0.02) and correlated with 24-hour SBP (r = 0.63; P < 0.01) and LVMI (r = 0.66; P < 0.01). In conclusion, this prospective crossover study confirms that DHD allows optimal control of BP, reduction in LVMI, and withdrawal of antihypertensive treatment. These effects seem to be related to reduction in ECW content.

Different prognostic impact of 24-hour mean blood pressure and pulse pressure on stroke and coronary artery disease in essential hypertension

BACKGROUND

We tested the hypothesis that the steady and pulsatile components of blood pressure (BP) exert a different influence on coronary artery disease and stroke in subjects with hypertension.

METHODS AND RESULTS

We analyzed data on 2311 subjects with essential hypertension. All subjects (mean age 51 years, 47% women) underwent off-therapy 24-hour ambulatory BP monitoring. Over a follow-up period of up to 14 years (mean 4.7 years), there were 132 major cardiac events (1.20 per 100 person-years) and 105 cerebrovascular events (0.90 per 100 person-years). After adjustment for age, sex, diabetes, serum cholesterol, and cigarette smoking (all P<0.01), for each 10 mm Hg increase in 24-hour pulse pressure (PP), there was an independent 35% increase in the risk of cardiac events (95% CI 17% to 55%). Twenty-four-hour mean BP was not a significant predictor of cardiac events after controlling for PP. After adjustment for age, sex, and diabetes (all P<0.05), for every 10 mm Hg increase in 24-hour mean BP, the risk of cerebrovascular events increased by 42% (95% CI 19% to 69%), and 24-hour PP did not yield significance after controlling for 24-hour mean BP. Twenty-four-hour PP was also an independent predictor of fatal cardiac events, and 24-hour mean BP was an independent predictor of fatal cerebrovascular events.

CONCLUSIONS

In subjects with predominantly systolic and diastolic hypertension, ambulatory mean BP and PP exert a different predictive effect on the cardiac and cerebrovascular complications. Although PP is the dominant predictor of cardiac events, mean BP is the major independent predictor of cerebrovascular events.

Original articles prognostic value of combined echocardiography and ambulatory blood pressure monitoring in hypertensive patients at low or medium cardiovascular risk

BACKGROUND

The clinical value of echocardiography and ambulatory blood pressure monitoring (ABPM) in hypertensive patients at low immediate risk of cardiovascular disease is still unknown.

METHODS

Echocardiography and ABPM were performed in 715 untreated subjects with essential hypertension World Health Organization/International Society of Hypertension stage I or II and low or medium cardiovascular risk defined by the absence of diabetes, previous cardiovascular events, left ventricular (LV) hypertrophy at electrocardiography, proteinuria, stages III-IV retinopathy and creatinine levels > 106.08 mmoll (1.2 mg/dl) and the presence of one or two traditional risk factors.

RESULTS

The LV mass was increased in 26.5% of these subjects. Subjects with a limited blood pressure reduction from day to night (non-dippers) were 11.3%. Over 1-13 years of follow-up, 31 subjects developed a first major cardiovascular event. The event rate (per 100 person-years) was 0.60 in the subgroup with a normal LV mass vs 1.63 in that with an increased LV mass (p < 0.017), and 0.74 in dippers vs 3.75 in non-dippers (p < 0.001). On multivariate analysis, the relative risk of cardiovascular events was 1.70 (95% confidence interval-CI 1.23-2.36) for each 11 g/m(2.7) increment in LV mass (p < 0.01), and 2.77 (95% CI 1.12-6.83) in non-dippers vs dippers (p < 0.05). Overall, on the basis of results of combined echocardiography and ABPM, 33% of subjects were at increased risk of future cardiovascular events.

CONCLUSIONS

At standard first-line work-up performed on hypertensive subjects at low or medium cardiovascular risk, combined echocardiography and ABPM identify an increase in the risk of subsequent cardiovascular disease in one third of subjects.

[Blood pressure components and target organ damage]

In a given hypertensive patient, clinically overt cardiovascular disease is often preceded by a number of signs of target organ damage at the cardiac, arterial and renal levels. These changes have been collectively defined "pre-clinical cardiovascular disease", and carry a substantially increased risk for future cardiovascular complications. The present article examines the relationship between blood pressure components and target organ damage in essential hypertension. Arterial pressure can be split into a steady component (represented by the mean arterial pressure), which is a measure of the average level of pressure in a given artery, and a pulsatile component (represented by the pulse pressure), which estimates the cyclic oscillations around the mean. All blood pressure components show a positive, linear correlation with left ventricular mass, both in the general population and in patients with essential hypertension. However, the association is significantly stronger for the steady blood pressure components (systolic and mean arterial pressure) than for the pulse pressure. Available data regarding arterial changes suggest that the association is partly different. The majority of available studies show that large-artery intima-media thickening and discrete atherosclerotic plaques are better predicted by pulse pressure than by other blood pressure components, particularly in the elderly. After the age of 60, there is clear-cut evidence for a J-shaped relationship between diastolic blood pressure and arterial thickening or plaques, while for younger age groups the relationship appears to be linear. These data might offer an explanation for the observed superior prognostic value of pulse pressure in the elderly. The relationship between the different blood pressure components and renal damage is more controversial. In summary, pulsatile, cyclic stress (as represented by pulse pressure) appears to be more important in determining arterial changes in hypertensive patients, while steady blood pressure components play a dominant role in the development of hypertensive left ventricular hypertrophy.

High-normal serum creatinine concentration is a predictor of cardiovascular risk in essential hypertension

BACKGROUND

Determination of serum creatinine concentration is recommended in all patients with hypertension as a marker of target organ damage. However, the possibility that creatinine values within the reference range might contribute to stratification of cardiovascular risk in essential hypertension has never been tested.

PATIENTS AND METHODS

In the setting of the Progetto Ipertensione Umbria Monitoraggio Ambulatoriale Study, for up to 11 years (mean, 4 years) we followed up 1829 white patients with hypertension (mean +/- SD age, 51 +/- 12 years; 53% men; office blood pressure, 157/98 mm Hg) free of cardiovascular events and with normal pretreatment creatinine levels (men, <136 micromol/L [<1.5 mg/dL]; women, <120 micromol/L [<1.4 mg/dL]) who also underwent 24-hour blood pressure monitoring and electrocardiography before therapy.

RESULTS

During follow-up, there were 175 fatal or nonfatal major cardiovascular morbid events (2.4 per 100 patient-years). Event rate increased progressively from the first to the fourth sex-specific quartiles of creatinine distribution (1.5, 2.3, 2.3, and 3.5 per 100 patient-years; P =.003 by log-rank test). After adjustment (in a multivariate Cox model) for age, sex, diabetes, cholesterol, smoking, left ventricular hypertrophy, and 24-hour pulse and mean blood pressures (P<.05 for all), creatinine concentration was an independent adverse predictor of cardiovascular morbid events (P =.01). The observed excess risk was 1.30 (95% confidence interval, 1.07-1.59) for a 20-micromol/L (0.23-mg/dL) increase in creatinine concentration.

CONCLUSIONS

A serum creatinine value within the reference range is a predictor of cardiovascular morbidity in white patients with essential hypertension. Its prognostic value persists after adjustment for several powerful confounders, including average 24-hour blood pressure and left ventricular hypertrophy.

Prognostic value of midwall shortening fraction and its relation with left ventricular mass in systemic hypertension

We followed 1,778 subjects (up to 12 years) with essential hypertension who underwent echocardiography at the time of their initial diagnostic workup. There were 166 major cardiovascular events during follow-up and the prognostic value of the midwall shortening fraction did not remain significant after controlling for left ventricular mass.

Relation between serum uric acid and risk of cardiovascular disease in essential hypertension. The PIUMA study

The question of serum uric acid as an independent risk factor in subjects with essential hypertension remains controversial. For up to 12 years (mean, 4.0) we followed 1720 subjects with essential hypertension. At entry, all subjects were untreated and all were carefully screened for absence of cardiovascular disease, renal disease, cancer, and other important disease. Outcome measures included total cardiovascular events, fatal cardiovascular events, and all-cause mortality. During 6841 person-years of follow-up there were 184 cardiovascular events (42 fatal) and 80 deaths from all causes. In the 4 quartiles of serum uric acid (division points: 0.268, 0.309, and 0.369 mmol/L [4.5, 5.2, and 6.2 mg/dL] in men; 0.190, 0.232, and 0.274 mmol/L [3.2, 3.9, and 4.6 mg/dL] in women), the rate (per 100 person-years) of cardiovascular events was 2.51, 1.48, 2.66, and 4.27, that of fatal cardiovascular events was 0.41, 0.33, 0.38, and 1.23, and that of all-cause deaths was 1.01, 0.55, 0.93, and 2.01, respectively. The relation between uric acid and event rate was J-shaped in both genders. After adjustment for age, gender, diabetes, total cholesterol/HDL cholesterol ratio, serum creatinine, left ventricular hypertrophy, ambulatory blood pressure, and use of diuretics during follow-up, uric acid levels in the highest quartile were associated with increased risk for cardiovascular events (relative risk, 1.73; 95% CI, 1.01 to 3.00), fatal cardiovascular events (relative risk, 1.96; 95% CI, 1.02 to 3.79), and all-cause mortality (relative risk, 1.63; 95% CI, 1.02 to 2.57) in relation to the second quartile. In untreated subjects with essential hypertension, raised uric acid is a powerful risk marker for subsequent cardiovascular disease and all-cause mortality.

Subclinical left ventricular dysfunction in systemic hypertension and the role of 24-hour blood pressure

The relation between blood pressure (BP) and left ventricular (LV) systolic function in systemic hypertension is controversial. We assessed the relation of LV midwall fractional shortening (FS) to 24-hour BP in 1,702 never-treated hypertensive subjects (age 48 +/- 12 years), who underwent 24-hour BP monitoring and echocardiography. Stress-corrected endocardial and midwall FS (the latter calculated taking into account the epicardial migration of midwall during systole) were predicted in hypertensives on the basis of the values observed in 130 healthy normotensives (age 43 +/- 13 years, office BP 126/78 mm Hg). Subjects below the fifth percentile of observed-to-predicted FS had depressed LV function. The use of midwall FS resulted in an increase from 3.5% to 17.5% in the proportion of patients with depressed chamber function. Compared with the group with normal function, subjects with low midwall LV function had similar office systolic BP (155 +/- 21 vs 154 +/- 17 mm Hg), but increased 24-hour systolic BP (140 +/- 17 vs 133 +/- 12 mm Hg, p <0.001). Midwall FS had a closer negative relation to 24-hour systolic BP than to office systolic BP (r = -0.27 vs -0.08, p <0.001), whereas this difference was not apparent for diastolic BP (r = -0.23 vs -0.20). Compared with endocardial FS, midwall FS had a stronger inverse association to LV mass (r = -0.45 vs -0.16, p <0.001). Thus, an increased 24-hour BP load may chronically lead to depressed myocardial function in systemic hypertension in the absence of clinically overt heart disease.

Manometric investigation of anorectal function in early and late stage Parkinson's disease

Abnormal gastrointestinal function is relatively frequent in Parkinson's disease, and constipation is a disturbing symptom in many patients. However, it remains to be established whether anorectal abnormalities are characteristic of the late stages of the disease. Clinical and anorectal manometric function were investigated in groups of early and late stage parkinsonian patients. Thirty one patients (19 men, 12 women, age range 22 to 89 years) entered the study. The disease severity was assessed by Hoehn and Yahr staging: there were four (12.9%) stage I, seven (22.6%) stage II, 10 (32.2%) stage III, and 10 (32.2%) stage IV patients. Anorectal variables were measured by standard manometric equipment and techniques. Values obtained in early stage patients (Hoehn and Yahr stage I and II) were compared with those obtained in late stage patients (Hoehn and Yahr stage III and IV). Overall, more than 70% of patients complained of chronic constipation, with chronic laxative use reported in more than 30%. Late stage patients were slightly older than their early stage counterparts. Pelvic floor dyssynergia was documented in more than 60% of patients. Manometric variables were not different in the two groups. In conclusion, defecatory dysfunction is frequent in Parkinson's disease, it is not confined to late stage patients, and it is found early in the course of the disease. This has potential implications for a targeted therapeutic approach.

Survival of vascular access during daily and three times a week hemodialysis

AIM

A major cause of morbidity for hemodialysis patients is vascular access failure and/or occlusion. It is commonly believed that an increased frequency of dialysis sessions, among other factors, might lead to a higher rate of fistula complications.

MATERIALS AND METHODS

To evaluate if patients on daily hemodialysis carry a higher risk of vascular access occlusion, we examined the incidence rate of access occlusion and the survival function of native vascular accesses in patients undergoing daily dialysis (DD; n = 24) as compared to patients on standard three times a week hemodialysis (TWD; n = 124).

RESULTS

The mean follow-up time was 3.6 years. In the TWD group 42 patients had a first-access closure, whereas only 2 patients out 24 had a similar event in the DD group. The proportion of first-access closure was 33.9% for TWD and 8.3% for DD (p < 0.01). The incidence rate was 9.8 (95% CI: 7.2 -13.2) and 2.2 (95% CI: 0.4 - 7.1) events per 100 patient-years for TWD and DD, respectively. The rate difference was 7.6 (95% CI 3.4 - 11.9) events per 100 patient-years, and the unadjusted risk ratio was 4.5 (95% CI: 1.2 - 16.9; p < 0.01). The mean vascular access survival before closure was 3.3 years in TWD and 3.7 years in DD. Survival curves, obtained considering the first-access closure as the endpoint, showed a significant difference between DD and TWD (log-rank 5.16; p < 0.05). In a Cox-proportional hazard model the relative risk (RR) of vascular-access closure in TWD remained significant (RR = 4.3; 95% CI 1.1 - 18.2) after adjustment for age.

CONCLUSION

The results of this observational study, conducted on a limited number of DD patients, suggest that daily dialysis might not have an adverse prognostic significance for access closure.

Value of a simple echocardiographic linear predictor of left ventricular mass in systemic hypertension

The need for calculations limits the clinical use of left ventricular (LV) mass. Because LV mass is strictly dependent on wall thickness for every given value of LV external dimension, we tested the clinical value of the sum of LV external dimension plus ventricular septal thickness plus posterior wall thickness as predictors of standard LV mass. We studied 295 healthy normotensive subjects and 1,686 subjects with systemic hypertension, followed up for 1 to 9 years. In the normotensive group, the predictor of LV mass showed a very close association with standard LV mass according to an allometric model (LV mass [g] = 0.230 x LV mass predictor [cm]3.01), with 99.7% of LV mass variability explained by the model. Also, in the hypertensive group, the LV mass predictor showed a very close allometric relation to standard LV mass (R2 = 0.998). During follow-up there were 154 cardiovascular morbid events and 50 deaths from all causes. The risk of cardiovascular morbid events and that of death increased to a similar extent with LV mass normalized by body surface area, height or height2.7, as well as with the LV mass predictor. The risk estimates for cardiovascular morbidity and all-cause mortality provided by models including either LV mass predictor or LV mass uncorrected or corrected by height, body surface area, or height2.7 did not show any statistical differences between the different models. In conclusion, the sum of LV external dimension plus ventricular septum thickness plus posterior wall thickness, easily measurable from the M-mode echocardiographic tracing, very closely predicts standard LV mass in adult hypertensive subjects. The prognostic value of this measure does not differ from that of standard LV mass.

Circulating insulin and insulin growth factor-1 are independent determinants of left ventricular mass and geometry in essential hypertension

BACKGROUND

It is unclear whether insulin and insulin-like growth factor-1 (IGF-1) are independent determinants of left ventricular (LV) mass in essential hypertension.

METHODS AND RESULTS

We studied 101 never-treated nondiabetic subjects with essential hypertension. All had 24-hour noninvasive ambulatory blood pressure (ABP) monitoring and a 75-g oral glucose tolerance test. We determined fasting glucose, insulin, and IGF-1 and postload glucose and insulin 2 hours after glucose. Insulin resistance was estimated by the homeostasis model assessment (HOMA(IR)) formula. LV mass showed an association with body mass index (BMI) (r=0.47; P<0.01), postload insulin (r=0.54; P<0.01), HOMA(IR) (r=0.39; P<0.01), and IGF-1 (r=0. 43; P<0.01) and a weaker association with average 24-hour systolic and diastolic ABPs (r=0.29 and r=0.26; P<0.05) and basal insulin (r=0.31; P<0.05). Relative wall thickness was positively related to IGF-1 (r=0.39; P<0.01) but not to fasting or 2-hour postload insulin, HOMA(IR), and glucose. In a multiple regression analysis, the final LV mass model (R(2)=0.64) included IGF-1, postload insulin, average 24-hour systolic ABP, sex, and BMI. IGF-1 and postload insulin accounted for >40% of variability of LV mass. The final model (R(2)=0.36) for relative wall thickness included IGF-1 (16% total explained variability), average 24-hour systolic ABP, sex, BMI, and age but not insulin and HOMA(IR).

CONCLUSIONS

These data indicate that insulin and IGF-1 are powerful independent determinants of LV mass and geometry in untreated subjects with essential hypertension and normal glucose tolerance.

Calcium antagonists and cardiovascular risk in patients with hypertension and Type 2 diabetes mellitus: evidence from the PIUMA Study. Progetto Ipertensione Umbria Monitoraggio Ambulatoriale

We conducted a retrospective analysis of all subjects with essential hypertension and Type 2 diabetes mellitus enrolled in the PIUMA (Progetto Ipertensione Umbria Monitoraggio Ambulatoriale) registry, in order to evaluate whether the use of calcium antagonists is associated with an increase in cardiovascular risk in these subjects. One hundred and sixty-four consecutive subjects with no previous cardiovascular morbid events and coexistence of essential hypertension and Type 2 diabetes mellitus were studied before therapy and followed for up to 12 years (mean 5). There were periodical contacts with family doctors and patients in order to ascertain the occurrence of major cardiovascular events. The use of calcium antagonists that preceded the event was considered for classification. None of the patients was lost to follow-up. At entry, the patients who were subsequently given calcium antagonists (n=50) had a higher clinical (174/98 vs 161/92 mmHg, both p<0.01) and 24-hr ambulatory blood pressure (150/90 vs 141/84 mmHg, both p<0.01) than those who were not. During follow-up there were 53 major cardiovascular morbid events (6.46 per 100 person-years). The rate of total cardiovascular events [5.6 vs 6.8 events per 100 person-years, relative risk 0.88 (95% CI: 0.47-1.61)] and that of cardiac events [4.0 vs 3.3 events per 100 person-years, relative risk 1.33 (95% CI: 0.62-2.89)] did not differ between users of calcium antagonists and non-users. The use of angiotensin converting enzyme inhibitors (n=66) was unrelated to the risk of cardiovascular events (relative risk 1.24, 95% CI: 0.71-2.16). In a Cox multivariate analysis, only age (p=0.002) and 24-hr pulse pressure (p=0.04) were independent predictors of cardiovascular events. In conclusion, this cohort study does not support the hypothesis that use of calcium antagonists is associated with an excess risk of adverse cardiovascular events in uncomplicated subjects with essential hypertension and Type 2 diabetes mellitus.

Alpha-dihydroergocryptine in Parkinson's disease: a multicentre randomized double blind parallel group study

INTRODUCTION

A multicentre randomized double-blind parallel group study was carried out on 68 patients suffering from idiopathic Parkinson's disease (PD) treated with L-dopa for at least 1 year with inadequate therapeutic responsiveness. The aim of the study was to compare the efficacy of alpha-dihydroergocryptine (alpha-DHEC) vs lisuride as an adjunct therapy to L-dopa on dyskinesias and clinical fluctuations (Unified Parkinson's Disease Rating Scale [UPDRS] part IV), on the symptoms pattern (Columbia University Rating Scale [CURS]), on disability (Northwestern University Disability Scale [NUDS]), and to evaluate the incidence of adverse events.

PATIENTS AND METHODS

Thirty-two patients (18 males, 14 females with a mean age of 64.5+/-1.5 SEM) were randomized to alpha-dihydroergocryptine and 36 (16 males, 20 females with a mean age of 61.8+/-1.4) to lisuride. The treatment lasted 3 months and the dosage was increased until it reached 60 mg/day of alpha-dihydroergocryptine and 1.2 mg/day of lisuride, while the L-dopa dosage was kept constant in both groups. Per protocol and intention to treat analyses were performed on response variables.

RESULTS

The adjunctive treatment with the two dopamine agonists determined a significant improvement of PD symptoms in both groups. Alpha-dihydroergocryptine showed a superior efficacy in reducing the clinical complications (P < 0.01 by ANOVA). The number of patients complaining of adverse events was 8 out of 32 (25%) for alpha-dihydroergocryptine and 24/36 (67%) for lisuride (P < 0.05).

CONCLUSION

Alpha-dihydroergocryptine effect seems to be superior to that of lisuride both in terms of reduction of L-dopa therapy long term motor complications (UPDRS part IV) as well as in terms of the incidence and severity of adverse events.

Moderate and large doses of ethanol differentially affect hepatic protein metabolism in humans

The intake of approximately 70 g of alcohol impairs liver protein metabolism in healthy humans. To establish the threshold at which alcohol impairs hepatic protein metabolism in humans we compared the effects of 500 mL of water (control study), 300 (28.4 g ethanol) or 750 mL (71 g ethanol) of table wine on hepatic protein metabolism in three groups of healthy nonalcoholic volunteers. Hepatic protein metabolism was estimated (L-[1-14C]leucine infusion) by measuring the fractional secretory rates of albumin and fibrinogen during the overnight postabsorptive state (basal) and the subsequent administration of water or two different amounts of wine (300 or 750 mL) given with a liquid glucose-lipid-amino acid meal. During the meal, water did not affect fibrinogen fractional secretory rate and increased albumin fractional secretory rate by approximately 50% (P < 0.01). The 300 mL of wine increased albumin secretory rate by only approximately 20% (P < 0.01 vs. basal, P < 0.04 vs. water) and did not affect fibrinogen secretory rate. The 750 mL of wine profoundly impaired hepatic protein metabolism, decreasing the fractional secretory rates of albumin (P < 0.01 vs. water and 300 mL wine) and fibrinogen (P < 0.04 vs. water and 300 mL of wine) below the postabsorptive values. These results demonstrate that a moderate dose of alcohol (28 g, approximately 2 drinks) slightly affects postprandial hepatic protein metabolism by blunting the meal-induced increase in albumin synthesis, whereas it does not interfere with fibrinogen synthesis as do higher doses.

Prognostic significance of serial changes in left ventricular mass in essential hypertension

BACKGROUND

Increased left ventricular (LV) mass predicts an adverse outcome in patients with essential hypertension. The purpose of this study was to determine the relation between changes in LV mass during antihypertensive treatment and subsequent prognosis.

METHODS AND RESULTS

Procedures including echocardiography and 24-hour ambulatory blood pressure (BP) monitoring were performed in 430 patients with essential hypertension before therapy and after 1217 patient-years. Months or years after the follow-up visit, 31 patients suffered a first cardiovascular morbid event. The patients with a decrease in LV mass from the baseline to follow-up visit were compared with those with an increase in LV mass. There were 15 events (1.78 per 100 person-years) in the group with a decrease in LV mass and 16 events (3.03 per 100 person-years) in the group with an increase in LV mass (P=.029). In a Cox model, the lesser cardiovascular risk in the group with a decrease in LV mass (hazard ratio [HR], 0.46; 95% CI, 0.22 to 0.99) remained significant (P=.04) after adjustment for age (HR, 1.06; 95% CI, 1.03 to 1.10; P=.0008) and baseline LVH at ECG (HR, 3.85; 95% CI, 1.52 to 9.78; P=.012). In that model, baseline LV mass bordered on statistical significance (HR, 1.01; 95% CI, 1.00 to 1.03; P=.06). In the subset with LV mass > 125 g/m2 at the baseline visit (26% of subjects), the event rate was lower among the subjects who achieved regression of LVH than in those who did not (1.58 versus 6.27 events per 100 person-years; P=.002). This difference held in the multivariate analysis (HR, 0.18; 95% CI, 0.05 to 0.68).

CONCLUSIONS

In essential hypertension, a reduction in LV mass during treatment is a favorable prognostic marker that predicts a lesser risk for subsequent cardiovascular morbid events. Such an association is independent of baseline LV mass, baseline clinic and ambulatory BP, and degree of BP reduction.

Nicotinamide counteracts alcohol-induced impairment of hepatic protein metabolism in humans

We have recently shown that a large amount of wine (750 mL, approximately 70 g of alcohol) markedly impairs postprandial hepatic protein metabolism in healthy subjects. This is probably due to the shift in the intracellular redox state (increased NADH/NAD+) induced by ethanol oxidation. If this hypothesis is true, the administration of nicotinamide (NAD+ precursor) should provide NAD+ in excess and thus correct the NADH/NAD+ abnormalities and prevent the ethanol hepatotoxicity. Whole-body protein metabolism and the fractional secretory rates of hepatic (albumin, fibrinogen) and extra-hepatic (immunoglobulin G, IgG) plasma proteins were measured in the basal postabsorptive and in the absorptive states in 15 healthy subjects, that had been assigned to three groups matched for age and body mass index. During the absorptive state (intragastric meal), the three groups received water (control), 750 mL of wine, or 750 mL of wine + 1.25 g of nicotinamide, respectively. The redox state was estimated by determining the plasma lactate/pyruvate ratio. Compared with the basal state, wine alone increased the lactate/pyruvate ratio twofold and depressed the fractional secretory rates of albumin and fibrinogen (P < 0.01 vs. control and nicotinamide); nicotinamide reduced the effects of wine on the lactate/pyruvate ratio (P < 0.02 vs. wine alone) and prevented the reduction of albumin and fibrinogen secretory rates (P > 0.05 vs. control). These results indicate that nicotinamide counteracts the acute hepatotoxic effects of ethanol by ameliorating the redox state.

Pharmacokinetic profile and endocrine effects of posatirelin treatment in healthy elderly subjects

The pharmacokinetics and endocrine effects of a therapeutic dose (10 mg/day) of posatirelin (L-pyro-2-aminoadipyl-L-leucyl-L-prolinamide) were investigated in healthy elderly subjects. Posatirelin was given once daily by intramuscular injection for 7 days. Pharmacokinetic parameters were estimated using a model-independent approach. The plasma concentrations of free triiodotyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) and the circadian rhythms of prolactin and cortisol were considered as indicator variables of endocrine response to posatirelin administration. Posatirelin was well tolerated and no significant adverse effects were observed during the study. Peak plasma concentration (Cmax), time of peak plasma concentration (tmax), area under the plasma concentration-time curve from time zero to infinity (AUC0-infinity), elimination half-life (t1/2), and total clearance (CI/F) were measured after single-dose intramuscular injection (day 1) and after multiple-dose administration (day 7). There were no significant changes in these parameters after multiple-dose administration (day 7). Posatirelin induced a progressive reduction in basal TSH levels and maximum response. There were no significant changes during treatment in the time at which basal levels of FT3 and FT4 occurred, and these levels remained within the normal range throughout the study. The circadian rhythms of cortisol and prolactin were not influenced by posatirelin treatment. The pharmacokinetics of posatirelin were not time dependent, and the drug did not accumulate after multiple-dose administration. Short-term treatment with posatirelin did not induce clinically relevant endocrine consequences in healthy elderly subjects.

Pharmacokinetic Study of Triflusal in Elderly Subjects After Single and Repeated Oral Administration

In this study the single-dose and steady-state pharmacokinetics of unchanged triflusal and its metabolite 2-hydroxy-4-trifluoromethylbenzoic acid (HTB) were studied in 12 elderly subjects treated with a single oral administration of 300 mg triflusal and repeated oral administrations of 300 mg triflusal b.i.d. for 13 days. After a single administration, unchanged triflusal is promptly absorbed (t(max) 0.75 h, C(max) 3.83 &mgr;g/mL) and rapidly depleted from the systemic circulation. Its concentration was measurable only up to 1 to 4 h after administration. The apparent terminal half-life was 0.85 h. HTB proves to be quickly generated from triflusal (t(max) 2.00 h, C(max) 39.88 &mgr;g/mL) and slowly eliminated from the body (t = 54.6 h). With the dose regimen proposed, unchanged triflusal does not accumulate in the body. Conversely, HTB plasma concentration builds up progressively toward steady-state levels of approximately 102 &mgr;g/mL after 4 to 5 d of treatment. No substantial change in peak time, elimination rate constant and half-life evaluated after single-dose treatment was observed on multiple-dose regimen for unchanged triflusal and its metabolite HTB. Therefore, our findings do not indicate a time-dependent pharmacokinetics for triflusal. There were no changes in blood pressure, heart rate or laboratory safety date, i.e., biochemical or hematological profiles.

Contribution of amino acids and insulin to protein anabolism during meal absorption

The contribution of dietary amino acids and endogenous hyperinsulinemia to prandial protein anabolism still has not been established. To this end, leucine estimates ([1-14C]leucine infusion, plasma alpha-ketoisocaproic acid [KIC] specific activity [SA] as precursor pool SA) of whole-body protein kinetics and fractional secretory rates (FSRs) of albumin, fibrinogen, antithrombin III, and immunoglobulin G (IgG) were measured in three groups of healthy volunteers during intragastric infusion of water (controls, n = 5), liquid glucose-lipid-amino acid (AA) meal (meal+AA, n = 7), or isocaloric glucose-lipid meal (meal-AA, n = 7) that induced the same insulin response as the meal+AA. The results of this study demonstrate that 1) by increasing (P < 0.01) whole-body protein synthesis and decreasing (P < 0.01) proteolysis, dietary amino acids account for the largest part (approximately 90%) of postprandial protein anabolism; 2) the ingestion of an isocaloric meal deprived of amino acids exerts a modest protein anabolic effect (10% of postprandial protein anabolism) by decreasing amino acid oxidation and increasing (P < 0.01) albumin synthesis; 3) albumin FSR is increased (approximately 20%) by postprandial hyperinsulinemia (meal-AA) and additionally increased (approximately 50%) by amino acid intake (meal+AA); 4) IgG FSR is stimulated (approximately 40%) by amino acids, not by insulin; and 5) fibrinogen and antithrombin III FSR are not regulated by amino acids or insulin.

Prognostic value of left ventricular mass and geometry in systemic hypertension with left ventricular hypertrophy

To determine the independent prognostic significance of left ventricular (LV) mass and geometry (concentric vs eccentric pattern) in hypertensive subjects with LV hypertrophy at echocardiography, 274 subjects were followed for up to 8.7 years (mean 3.2). All patients had systemic hypertension and LV mass > or = 125 g/body surface area (BSA) and underwent ambulatory blood pressure (BP) monitoring and echocardiography before treatment. Eccentric and concentric hypertrophy were defined by the ratio between LV posterior wall thickness and LV radius at telediastole <0.45 and > or = 0.45, respectively. Age, sex ratio, body mass index, office BP and serum glucose, cholesterol, and triglycerides did not differ between the groups with eccentric (n=145) and concentric (n=129) hypertrophy. Average 24-hour daytime, and nighttime systolic ambulatory BPs were higher in concentric than in eccentric hypertrophy (all p <0.01). LV mass was slightly greater in concentric than in eccentric hypertrophy (157 vs 149 g/BSA, p <0.05). Endocardial and midwall shortening fraction were lower in concentric than in eccentric hypertrophy (96.5% vs 106.0% of predicted and 71.4% vs 89.7% of predicted, respectively; both p <0.01). The rate of major cardiovascular morbid events was 2.20 and 3.34 per 100 patient-years in eccentric and concentric hypertrophy, respectively (log rank test, p=NS). Age >60 and LV mass above median (145 g/BSA) were significant adverse prognostic predictors, while LV geometry (eccentric vs concentric hypertrophy) and ambulatory BP were not. The event rates per 100 patient-years were 1.38 and 3.98, respectively, in the patients with LV mass below and above median (age-adjusted relative risk 2.70; 95% confidence interval [CI] 1.03 to 6.63; p=0.015). In hypertensive subjects with established LV hypertrophy, LV mass, but not its geometric pattern, provides important prognostic information independent of conventional risk markers including office and ambulatory BP.

Dexamethasone suppression test in elderly patients with dementia of Alzheimer type, vascular dementia and stroke: a re-evaluation of its applicability

In order to evaluate the prevalence of non-suppression after dexamethasone in psychogeriatrics and to further verify the reliability of the neurobiological information obtained, dexamethasone suppression test was carried out in a geriatric population composed of patients with dementia of Alzheimer type, vascular dementia, stroke and age and sex-matched controls. Basal cortisol levels did not differ among groups and was positively correlated to age. Prevalence of non-suppression, defined according to Carroll's criterion was high in the pathological groups studied, and relatively high in controls, showing no diagnostic value. Unlikely suppressors, the time course of mean plasma corticol levels of non-suppressors was highly heterogeneous in each group considered, especially in the pathological groups. More restrictive criteria for the definition of non-suppressors are proposed, in order to increase the specificity of the test when applied to psychogeriatrics.

Ethanol impairs post-prandial hepatic protein metabolism

The effects of acute ethanol ingestion on whole body and hepatic protein metabolism in humans are not known. To simulate social drinking, we compared the effects of the association of a mixed meal (632 kcal, 17% amino acids, 50% glucose, 33% lipids) with a bottle of either table wine (ethanol content 71 g) or water on the estimates ([1-14C]-leucine infusion) of whole body protein breakdown, oxidation, and synthesis, and on the intravascular fractional secretory rates (FSR) of hepatically (albumin, fibrinogen) and extrahepatically (IgG) synthesized plasma proteins in two randomized groups (ethanol n = 7, water n = 7) of healthy nonalcoholic volunteers. Each study was carried out for 8 h. Protein kinetics were measured in the overnight post-absorptive state, over the first 4 h, and during a meal infusion (via a nasogastric feeding tube at constant rate) combined with the oral ingestion of wine or water, over the last 4 h. When compared with water, wine ingestion during the meal reduced (P < 0.03) by 24% the rate of leucine oxidation, did not modify the estimates of whole body protein breakdown and synthesis, reduced (P < 0.01) by approximately 30% the FSR of albumin and fibrinogen, but did not affect IgG FSR. In conclusion, 70 g of ethanol, an amount usual among social drinkers, impairs hepatic protein metabolism. The habitual consumption of such amounts by reducing the synthesis and/or secretion of hepatic proteins might lead to the progressive development of liver injury and to hypoalbuminemia also in the absence of protein malnutrition.

Adverse prognostic significance of concentric remodeling of the left ventricle in hypertensive patients with normal left ventricular mass

OBJECTIVES

We examined the prognostic significance of concentric remodeling of the left ventricle in patients with essential hypertension and normal left ventricular mass on echocardiography.

BACKGROUND

An echocardiographic pattern of concentric remodeling of the left ventricle has been associated with clinical features of increased cardiovascular risk, but the independent prognostic value of this finding in hypertensive patients with normal left ventricular mass has not been established.

METHODS

Six hundred ninety-four patients with essential hypertension and normal left ventricular mass (< 125 g/m2) on echocardiography were prospectively followed up for < or = 7.7 years (mean 2.71). Baseline echocardiography and 24-h noninvasive ambulatory blood pressure monitoring were performed in all patients at the time of initial diagnostic evaluation. Concentric remodeling was defined by the thickness of the septum or posterior wall divided by the left ventricular radius at end-diastole > or = 0.45.

RESULTS

Prevalence of concentric remodeling was 39.2%. During follow-up there were 29 cardiovascular morbid events. Cardiovascular morbidity, expressed as the combined number of fatal and nonfatal events per 100 patient-years, was 1.53 in the overall study group, 1.12 in the subgroup with normal left ventricular geometry and 2.39 in that with concentric remodeling. After assessment of the independent association with several covariates (age, gender, diabetes, left ventricular mass index, mean clinic blood pressure and mean 24-h ambulatory blood pressure) in Cox proportional hazard models, the risk of cardiovascular morbid events was higher in the group with concentric remodeling than in that with normal geometry (relative risk 2.56, 95% confidence interval 1.20 to 5.45, p < 0.01).

CONCLUSIONS

Concentric remodeling of the left ventricle, defined by the thickness of the septum or posterior wall divided by the left ventricular radius at end-diastole > or = 0.45, is an important and independent predictor of increased cardiovascular risk in hypertensive patients with normal left ventricular mass on echocardiography.

Cardiovascular response to exercise in diabetic patients: influence of autonomic neuropathy of different severity

We investigated cardiovascular function and plasma catecholamine response during incremental exercise and recovery in diabetic patients with (DAN+) and without autonomic neuropathy (DAN-). The former group was divided according to the presence of parasympathetic (DAN+PH-) or associated parasympathetic and sympathetic (DAN+PH+) damage to the autonomic nervous system. A group of healthy volunteers was studied as a control group. All the patients and control subjects underwent a submaximal or symptom-limited incremental exercise test using a cycle-ergometer. Air flow and respiratory gas fractions were sampled at the level of the mouth allowing a breath-by-breath analysis of oxygen consumption (VO2). Heart rate and systolic blood pressure were recorded and venous blood samples were obtained from the patients at rest and during each minute of exercise and recovery to measure norepinephrine and epinephrine plasma levels. Haemodynamic parameters and plasma catecholamines were computed at rest and at 25, 50, 75 and 100% of the peak VO2 (VO2max). The breath-by-breath relationships among VO2, heart rate and VO2/heart rate against work were assessed during exercise for patients and control subjects. While VO2max in absolute values was not significantly different among the diabetic groups, VO2 max was much less in diabetic patients than in control subjects (p < 0.01). During exercise the rate of heart rate, systolic blood pressure, norepinephrine and epinephrine increase was different among the diabetic groups, being significantly blunted in DAN+PH+. The VO2/work relationship of the three diabetic groups was similar but markedly reduced in respect to that of control subjects (p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Ambulatory blood pressure. An independent predictor of prognosis in essential hypertension

To determine the prognostic significance of ambulatory blood pressure, we prospectively followed for up to 7.5 years (mean, 3.2) 1187 subjects with essential hypertension and 205 healthy normotensive control subjects who had baseline off-therapy 24-hour noninvasive ambulatory blood pressure monitoring. Prevalence of white coat hypertension, defined by an average daytime ambulatory blood pressure lower than 131/86 mm Hg in women and 136/87 mm Hg in men in clinically hypertensive subjects, was 19.2%. Cardiovascular morbidity, expressed as the number of combined fatal and nonfatal cardiovascular events per 100 patient-years, was 0.47 in the normotensive group, 0.49 in the white coat hypertension group, 1.79 in dippers with ambulatory hypertension, and 4.99 in nondippers with ambulatory hypertension. After adjustment for traditional risk markers for cardiovascular disease, morbidity did not differ between the normotensive and white coat hypertension groups (P = .83). Compared with the white coat hypertension group, cardiovascular morbidity increased in ambulatory hypertension in dippers (relative risk, 3.70; 95% confidence interval, 1.13 to 12.5), with a further increase of morbidity in nondippers (relative risk, 6.26; 95% confidence interval, 1.92 to 20.32). After adjustment for age, sex, diabetes, and echocardiographic left ventricular hypertrophy (relative risk versus subjects with normal left ventricular mass, 1.82; 95% confidence interval, 1.02 to 3.22), cardiovascular morbidity in ambulatory hypertension was higher (P = .0002) in nondippers than in dippers in women (relative risk, 6.79; 95% confidence interval, 2.45 to 18.82) but not in men (P = .91). Our findings suggest that ambulatory blood pressures stratifies cardiovascular risk in essential hypertension independent of clinic blood pressure and other traditional risk markers including echocardiographic left ventricular hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)

Physiological increments in plasma insulin concentrations have selective and different effects on synthesis of hepatic proteins in normal humans

These studies tested the hypothesis that physiological increments in plasma insulin concentrations have selective effects on the synthesis of hepatic proteins in humans. Leucine kinetics and fractional synthetic rates of albumin, fibrinogen, antithrombin III, and apoB-100 were determined in 6 normal subjects, on two different occasions during either the infusion of saline (control study) or a euglycemic-hyperinsulinemic (0.4 mU.kg-1 x min-1 for 240 min) clamp, by a primed-constant infusion of [1-14C]Leu. The insulin infusion significantly decreased the rates of nonoxidative Leu disposal (1.70 +/- 0.10 vs. control 2.06 +/- 0.09 mol.kg-1 x min-1), increased the albumin (7.2 +/- 0.4 vs. 6.2 +/- 0.6%/day), decreased the fibrinogen (18 +/- 1 vs. 23 +/- 2%/day), and antithrombin III (28 +/- 3 vs. 40 +/- 4%/day) fractional synthetic rate, whereas it did not affect the total apoB-100 (49 +/- 5 vs. 52 +/- 6%/day) fractional synthetic rate. Thus, the insulin-induced decrement in the estimates of whole-body protein synthesis (nonoxidative Leu disposal) represents the mean result of opposite effects of hyperinsulinemia on the synthesis of proteins with different functions. The positive effect of insulin on albumin synthesis may play an important anabolic role during nutrient absorption by promoting the capture of a relevant amount of dietary essential amino acids into the protein, whereas the negative effect of insulin on fibrinogen synthesis might, at least partially, account for the increased plasma fibrinogen concentrations previously reported in poorly controlled diabetic patients.

[Usefulness of plantar pressure measurement for the prevention and treatment of neuropathic diabetic foot]

A disease of the legs, and more specifically of the feet, is a frequent occurrence in diabetic patients and can lead to the major risk of amputation. The pathogenesis of this disease is complex and due to vascular damage and neuropathy. The neuropathic ulcer is a typical clinical manifestation of the "diabetic foot". The pathogenesis of this manifestation is discussed. The most important thing is to prevent this disease. The diabetologist must regularly examine the feet of the patients and measure the foot pressure. We discuss a new instrument, the Dynamic System, which we believe of great help to diabetologist in measuring the foot pressure of diabetic patients.