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Biomedical subjects

P Cugini

Publications and source records attributed to P Cugini.

At least 217 records · Page 12Linked to original sources
PubMedDate not supplied

Construction of age-related reference limits for 24-h blood pressure pattern.

Blood pressure (BP) is recursively variable during the day-night cycle because of a physiological circadian rhythm. The aim of this study is, therefore, to show how to construct the population reference limits (desms) for BP in its time varying 24-h pattern, starting from a small sample, in order to facilitate their use in a local context. The sample for standardization comprised 427 clinically healthy subjects (211 males and 216 females), ranging in age from 16 to 100 years, attending their routine activities. The procedure begins with the statistical biometry related to the sample, and proceeds with the computation of the BP desms related to (1) the time-qualified discrete values; (2) the parameters of circadian rhythm; (3) the daily pressure load. The pertaining rules are explained step by stop, allowing each one to prepare the proper local desms for BP 24-h pattern. These standards may be useful for validating the individual BP monitoring according to the upper limits of the circadian physiological variability in the diagnostic procedure for identifying hypertensive subjects.

Adolescent↗
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Who are the non-dippers? A better definition via the blood pressure circadian rhythm.

OBJECTIVE: The non-dipping phenomenon (NDP) can be better interpreted when considering that blood pressure (BP) shows a within-day variability which is the expression of a circadian rhythm (CR). PATIENTS AND METHODS: The NDP was investigated at the light of the BP CR by analysing the ambulatory BP monitoring of 298 essential hypertensive patients (EHP), 84 secondary hypertensive patients (SHP), as well as 93 normotensive subjects (NS). According to the rhythmometric validation, the investigated subjects were defined "rhythmic" (R) or "non-rhythmic" (NR). RESULTS: The non-dippers (ND) were found among not only the EHP (14%) and SHP (27%) but also the NS (16%). The percentages of R ND were 9%, 4% and 20%, respectively in EHP, SHP and NS. The R ND were characterized by a nocturnal phase-shift (100% in NS), associated with an amplitude increase (50% in EHP) or a mesor increase (50% in EHP; 100% in SHP) in BP CR. The NR ND were characterized by an amplitude almost negligible (100% in NS) associated with a mesor increase (100% in EHP; 100% in SHP). CONCLUSIONS: The detection of a NDP associated with a rhythmicity suggests that the criterion with which the ND are identified cannot be used for making inferences on the BP CR in HP or NS. The rhythmic characteristics in ND suggest that the rhythmometric analysis is fundamental for identifying the abnormal time structure of BP 24-h values in the presence of the NDP.

Adult↗
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The chaotic component of human heart rate variability shows a circadian periodicity as documented by the correlation dimension of the time-qualified sinusal R-R intervals.

OBJECTIVE: This study investigates the hypothesis that the nonlinear component of human heart rate (HR) variability might show a periodic structure over the 24-h span. Such a postulate could explain how the chaotic component might coexist with the deterministic periodic variability of instantaneous HR in beat per minute. MATERIALS AND METHODS: The sinusal R-R intervals (sRRi) of the Holter EKG of 10 clinically healthy subjects (5 M, 5 F, 23-30 years) were analyzed per each hour of the day-night span according to two methods for the nonlinear chaotic variability, i.e., the correlation dimension method, and the linear periodic variability, i.e., periodic regression analysis. RESULTS: The hourly-qualified correlation integrals were found to show a significant circadian rhythm, with an acrophase located during the night in coincidence with the longest duration of the sRRi and the lowest rate of cardiac pulse. CONCLUSIONS: The rhythmic structure of the chaotic component of the human HR variability let us to think that a deterministic periodic chaos of fractal type regulates the nonlinear cardiac dynamics. Such a periodic structure allows the chaos to be compatible with the deterministic linear periodicity of circadian type which characterizes the within-day variability of human HR.

Adult↗
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Lower 24-h blood pressure regimen in subjects with a familial genealogy of longevity.

OBJECTIVE: This study investigates the 24-h blood pressure (BP) pattern in longevous subjects and their progeny, in order to validate the hypothesis that the human beings who live beyond their longest expectancy of life should be protected from developing hypertension. Such a characteristic feature is supposed to be a biological aspect of human longevity which can be transmitted to the progeny. MATERIALS AND METHODS: The study was carried out on 92 elderly subjects, (45 M, 47 W, 76-102 years), and 28 firstborn descendants of the first (7 M, 7 W, 36-55 years) and second (7 M, 7 W, 16-26 years) generation, in clinical health. The control subjects were 308 clinically healthy individuals (154 M, 154 F, 16-75 years) of the common population, stratified by age. RESULTS: The longevous subjects were found to show a diastolic daily mean level less pronounced than expected, according to the BP age-related trend in the common population. Both the children and grandchildren of the longevous subjects were seen to show a systolic and diastolic daily mean level significantly less pronounced than in their coeval subjects of the common population. CONCLUSIONS: Because of the unexpected lower diastolic BP daily mean level in the very old subjects, the hypothesis that the longevous subjects might be protected from developing hypertension via the arteriolar vasoconstriction seems to be confirmed. Because of the lower systolic and diastolic BP in young and adult subjects with a positive familiarity for longevity, the hypothesis that the hemodynamic protection from senile hypertension might be an inheritable biological feature of the longevity seems to be acceptable.

Adolescent↗
PubMedDate not supplied

Age-related changes in blood pressure twenty-four-hour pattern in normotensive subjects of two populations.

OBJECTIVES: This study investigates the systolic (S) and diastolic (D) blood pressure (BP) 24-h pattern in normotensive healthy subjects belonging to two populations characterized respectively by a "non-salt culture" (Italian subjects) and a "salt culture" (Japanese subjects) in their dietary salt intake (4-6 g/day in Italians vs 10-12 g/day in Japanese). The comparison was performed by taking into consideration the within-day variability (WDV) and circadian rhythmicity (CR) of BP with respect to age. MATERIALS AND METHODS: Subjects investigated were 862 normotensive healthy subjects (308 Italians and 554 Japanese), stratified by age from 16 to 75 years, who volunteered for a noninvasive BP monitoring in an ordinary day of their life. The SBP and DBP time series were analyzed via conventional parametric statistics as well as chronobiological procedures. RESULTS: The biometric estimates demonstrate that BP changes in its WDV and CR as a function of age in both populations. Despite the difference in their habitual salt intake, the age-related changes in BP WDV and CR result to be almost comparable at the cross-sectional contrasts, giving origin to age-related trends for SBP and DBP which are significantly parallel. CONCLUSIONS: The comparability of BP WDV and CR in the two populations with a substantial difference in salt intake suggests that the normotensive status in human races is realized despite the difference in their habitual salt intake. This implies the ancestral development of mechanism(s) of adaptation to the possible "sodium luxus consumption". Although the adaptive mechanisms which provide a normotensive regimen under different conditions of sodium intake are almost unexplored, the racial adaptation to dietary salt constitutes, however, the initial condition for the cause-effect nexus between dietary salt intake and hypertension in human populations.

Adolescent↗
PubMedDate not supplied

Hunger sensation in Graves' disease before and after pharmacological therapy.

PURPOSE: Hunger sensation (HS) provides information about the need of eating in order to counterbalance the energy expenditure (EE). HS was, thus, investigated in patients affected by Graves' disease (PAGD), a clinical condition characterized by excessive EE. MATERIALS AND METHODS: Ten newly diagnosed PAGD were investigated before and after therapy. Thirty clinically healthy subjects (CHS) were investigated as controls. The investigated subjects were asked to provide the 24-h profile of their HS by subjectively self-rating (from 1 to 10 hunger units) their orectic perception (OP) at regular intervals of 30 minutes (orexigram). The orexigrams were investigated via the conventional descriptive statistics as well as the Single-Cosinor method. RESULTS: PAGD were found to show a very consistent increase of their HS (hyperorexia), whose day-night variability was, still, the expression of a circadian rhythm, characterized by an elevation in its oscillatory level and extent. Interestingly, the pre-treatment hyperorexia was seen to show a normalization (eurexia) after pharmacological therapy. CONCLUSIONS: According to these results, it can be affirmed that hyperorexia is a clinical sign of Graves' disease, which is obtained via mechanisms of tonic and amplitude modulation of the HS circadian rhythm. Because of the eurexia after remission, it can be argued that the hyperorexia is a theleological response really aimed at increasing food intake in order to counterbalance the excessive EE which characterizes the thyrotoxicosis.

Adult↗
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Age-related trend for blood pressure circadian rhythm in normotensive healthy subjects: estimates provided by the clinospectror method.

The present study investigates how blood pressure (BP) circadian rhythm (CR) changes in its rhythmic properties as a function of chronological age in normotensive healthy subjects (NHS). The age-related trend for BP CR was investigated via the Clinospectror method, a periodic-linear analysis of regression for rhythmic parameters. The study was performed on 437 NHS (219 males and 218 females, ranging in age from 1 year to 102 years), who were monitored in their 24-h BP via a noninvasive automated recorder. An age-related trend was detected for the three properties of BP CR, i.e., mesor (M), amplitude (A) and acrophase (cent). Such a trend was positive for M and A, and negative for cent. According to the clinospectrometric formula, the BP CR can be classified as a "dianaclinous rhythm", i.e., a rhythm which increases in its oscillatory level and extent with advancing years. The documented age-related trend for the rhythmic properties suggests that the biological clock which regulates the BP CR in human beings undergoes a resetting of its mechanisms of tonic, amplitude and phasic modulation as a function of chronological age. The readjustment of the pressure clock may be regarded as one of the physiological features which characterize the aging process in human beings.

Adolescent↗
PubMedDate not supplied

[Circadian periodicity in human heart rate daily variability disorders: subsequent demonstrations through a chronobiological approach to the values of estimated alpha exponent on sinusal R-R intervals].

OBJECTIVE: The present study is aimed at giving a further demonstration that the disorder in human heart rate variability is characterized by a circadian periodicity. Such an evidence has been provided by estimating the alpha exponent of the Lévy's stable distribution approximated to the histogram of the differences between the durations of two adjacent sinusal R-R intervals. MATERIALS AND METHODS: The purpose has been pursued by estimating the alpha exponent on fragments of one hour of the Holter electrocardiogram executed in 10 clinically healthy subjects (5 males and 5 females, ranging in age from 23 to 30 years). RESULTS: The chronobiological analysis of the hourly-qualified values of the alpha exponent has demonstrated a significant circadian rhythm for this coefficient. CONCLUSIONS: The significant circadian periodicity of the alpha exponent is a further evidence that the disorder in human heart rate variability, herein represented by the extreme variability of the differences between the durations of two consecutive sinusal R-R intervals, is characterized by a periodic recursivity.

Adult↗
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[Individualization of the "presumptive risk" of hypertensive crisis using fractals interpolation of the 24-hour arterial pressure. Study of patients with essential hypertension].

PURPOSE: The present study applies the "fractal interpolation" (FI) to blood pressure that was nonivasively and ambulatorily monitored over a day-night period in essential hypertensives. The purpose is the identification of cases who are at a "presumptive risk" (PR) for hypertensive crisis. MATERIALS AND METHODS: The investigation was performed on 380 ascertained cases of essential hypertension, who underwent a non-invasive ambulatory monitoring of 24-h blood pressure. The FI was applied to the ambulatory mean arterial pressure. RESULTS: The FI showed that the PR of hypertensive crisis can be found in 14% of the investigated essential hypertensive patients. Such a risk is not significantly higher in dippers as compared to non-dippers, and in those who showed a significant blood pressure circadian rhythm as compared to those who showed the blood pressure circadian rhythm to be abolished. Furthermore, no significant difference was found between the cases "at risk" and "not at risk" as far as the spectrum of harmonic formants of the 24-h blood pressure pattern is concerned. CONCLUSIONS: The PR of hypertensive crisis is not correlated to the dipping/nondipping condition, circadian rhythmicity and complex harmonic structure of 24-h blood pressure pattern. Its occurrence depends essentially from the disorder that is detectable in 24-h blood pressure pattern. Therefore, such a PR in essential hypertensives may be attributed to the mechanisms, likely neurovegetative, which confer a non-linear chaotic variability to 24-h blood pressure values.

Adult↗
PubMedDate not supplied

[Determination of the "presumptive risk" of hypertensive crisis with fractal interpolation of 24-hour arterial pressure. II: study with secondary hypertensive patients].

PURPOSE: The present study applies the "fractal interpolation" (FI) to 24-h blood pressure nonivasively and ambulatorily monitored over a day-night period in secondary hypertensives. The purpose is the evaluation of the prevalence for a "presumptive risk" (PR) of hypertensive crisis. MATERIALS AND METHODS: The study was carried out in 108 cases of secondary hypertension, who were non-invasively and ambulatorily monitored for their 24-h blood pressure values. The FI was applied to the time-qualified values of the mean arterial pressure. RESULTS: The PR of hypertensive crisis was found in 11% of the investigated secondary hypertensive patients. Such a risk shows a not significant prevalence in dippers as compared to non-dippers, and in those who showed a significant blood pressure circadian rhythm as compared to those who showed the blood pressure circadian rhythm to be abolished. Additionally, a not significant difference was found between the cases "at risk" and "not at risk" as far as the spectrum of harmonic formants of the 24-h blood pressure pattern is concerned. CONCLUSIONS: The PR of hypertensive crisis is not associated with the dipping/non-dipping phenomenon as well as the circadian rhythmicity of blood pressure. Its occurrence in secondary hypertensives is essentially related to the disorder that is detectable in blood pressure non-linear variability. Therefore, such a risk may be caused by neurovegetative mechanisms which notoriously confer a non-linear chaotic variability to 24-h blood pressure pattern.

Adult↗
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[Identification of "presumptive risk" of hypertension crises with fractal interpolation of the 24-hour arterial pressure. III: study of normotensive subjects].

PURPOSE: The present study is devoted to identify the normotensive subjects who are at a "presumptive risk" (PR) for hypertensive crisis, by applying the "fractal interpolation" (FI) to blood pressure 24-h pattern. MATERIALS AND METHODS: The investigation was performed on 109 ascertained cases of normotension, who underwent a non-invasive ambulatory monitoring of their 24-h blood pressure, by applying the FI to their daily mean arterial pressure. RESULTS: The study showed that the PR for hypertensive crisis can be found in 12% out of the investigated normotensives. The proportion of such a risk is not significantly higher in non-dippers as compared to dippers. Vice versa, the prevalence of cases with a PR for hypertensive crisis was found to be significantly increased in normotensives who were deprived by a significant blood pressure circadian rhythm as compared to those who showed the blood pressure circadian rhythm to be preserved. Furthermore, the cases "at risk" were found to show a different spectrum for the harmonic formants which compose the complex harmonic structure of the blood pressure 24-h variability. CONCLUSIONS: The PR for hypertensive crisis in normotensives seems to be increased by the loss of the blood pressure circadian rhythm, due to a change in the harmonic structure which confers the 24-h periodicity to the hemodynamic variable. This means that the abrogation of the blood pressure circadian rhythm in conditions of normotension promotes an adjunctive disorder for which the PR for hypertensive crisis is augmented.

Adult↗
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[Daily sensation of hunger, before and after phototherapy, in subjects with depression-type seasonal affective disorder].

OBJECTIVE: The present study investigates the daily pattern of hunger sensation (HS) in women affected by "seasonal affective disorder--depression type" (SAD-DT), before and after therapeutic exposure to bright light (phototherapy). The aim is to detect whether there are disorders in daily HS during the active phase of the disease which can be normalized by an effective treatment of the depressive status, via phototherapy. MATERIALS AND METHODS: Volunteered for the study 4 women affected by SAD-DT, 32-58 years old (BMI: 17.8-29.6 Kg/m2); 10 clinically healthy women (CHW), 21-52 years old (BMI: 23 e 25 Kg/m2) were recruited as controls. Both of the SAD-DT patients and CHW were asked to compile the "orexigram", which was chronobiometrically analyzed by means of the 1. conventional statistical methods; 2. rhythmometric analysis; 3. spectral analysis. RESULTS: Before phototherapy, the SAD-DT patients were found to be characterized by an increased HS (hyperorexia), with the circadian rhythm of the orectic stimulus (OS) which is shifted in its acrophase, being prone to become "free running". After phototherapy, the SAD-DT patients were found to show a little insignificant decrease in their OS, which still maintains a delayed phase in its circadian rhythm as well as the tendency to be "free running". CONCLUSIONS: The pre-treatment findings suggest that the SAD-DT patients are affected by hyperorexia associated with a "phase-shift" for the circadian periodicity of their HS, which is prone to the desynchronization. Such a dyschronism reinforces the hypothesis that the SAD-DT may be pathogenetically sustained by a mechanism of "phase-shift". The post-treatment findings suggest that both the hyperorexia and dyschronism of the orectic circadian rhythm are uncorrected by the phototherapy, even though the SAD-DT patients seem to have had beneficial antidepressive effects from the therapeutic intervention. The persisting dyschronism indicates that the photic stimulus is not able to completely reset the biological clock of the suprachiasmatic nuclei, at least for the phasic modulation of the HS circadian rhythm. The orexigram, thus, could be enclosed among the clinical tools in order to assess the complete efficacy of the phototherapy in SAD-DP patients.

Adult↗
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Circadian rhythm of hunger sensation in patients affected by dysthymic disorder.

PURPOSE: The present study investigates the daily pattern of hunger sensation (HS), namely orexia, in patients affected by "Dysthymic Disorder" (DD). The aim is to detect whether there are changes in the circadian rhythm (CR) of HS, herein investigated as a "marker rhythm", that can reveal a dysfunction of the "circadian biological clock" (CBC). In such a circumstance, one could be authorised to suggest a resynchronizing therapy, via antidepressant chronizing drugs and/or morning exposure to bright light, as it is currently done in other types of human depression, having a documented dysfunction of the CBC. MATERIALS AND METHODS: Volunteered with informed consent for the study 6 women (age = 34-56 years; mean BMI = 22.7 +/- 4.8 kg/m2) affected by DD. 10 clinically healthy women (CHW, age = 21-52 years; mean BMI = 24.0 +/- 0.5 kg/m2) were recruited as the controls. Both of the dysthymic patients (DP) and CHW were asked to compile the "orexigram", which was chronobiometrically analyzed by means of the 1. conventional statistical methods; 2. rhythmometric analysis for the CR; 3. spectral analysis for the harmonic components of the orexigram. RESULTS: The DP were found to be characterized by a normal daily level of HS, with 1. the CR of the orectic stimulus to be preserved and well located in its acrophase, and 2. the spectrogram of the orexigram to be substantially well configured. CONCLUSIONS: The above-cited results suggest that the DP show no alterations in the HS marker rhythm that can be taken as an evidence for declaring that the DD is not characterized by a relevant dysfunction of the CBC. Lacking in particular a phase-shift in HS marker rhythm, it can be argued that the DD is an affective disorder for which a resynchronizing therapy (exposure to bright light or pharmacological chronizers) seems to be "a priori" not indicated.

Adult↗
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Age-related trend in circadian rhythm of electrocardiographic sinusal R-R intervals in clinically healthy subjects.

It is a clinical observation that human HR shows a tendency to bradycardia with advancing age. In addition, there is experimental evidence that heart rate (HR) shows a circadian rhythm (CR) in healthy humans. Because of this background, the present study is devoted to investigate how the CR of the electrocardiographic sinusal R-R intervals (SRRI) changes its properties as a function of chronological age in healthy humans. The study was performed on 170 clinically healthy Japanese, ranging in age from 12 to 83 years (mean age +/- SD = 43 +/- 15 years), who were monitored in their electrocardiogram over the day-night span. An opposite age-related trend was detected for two properties of SRRI CR, i.e., mesor (positive trend) and amplitude (negative trend). Accordingly, the SRRI CR can be classified as an "amphiclinous rhythm", i.e., a rhythm in which the cardiac interbeat duration shows a progressive increase of its daily mean value along with a progressive deamplification of its oscillatory extent. Furthermore, the rhythm is characterized by a progressive anticipation in time of its oscillatory maximum of duration with advancing age. The findings suggest that the biological clocks regulating the HR CR in human beings undergo a resetting of their mechanisms of tonic, amplitude and phasic modulation as a function of age. The clock-mediated readjustment of the HR CR may be regarded as one of the mechanisms for explaining the bradycardia that is associated with the aging process in human beings.

Adolescent↗
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The ambulatory monitoring documents a more elevated blood pressure regimen (pre-hypertension) in normotensives with endothelial dysfunction.

PURPOSE: The present study investigates the blood pressure (BP) 24-h values in normotensives with and without endothelial dysfunction (ED). The scope is to detect differences in BP regimen supporting the hypothesis that the ED is associated with vasopressant effects that can cause a condition of "pre-hypertension". MATERIALS AND METHODS: Thirty-eight normotensives were investigated in their endothelial function by mean of the non-invasive post-ischemic brachial artery vasodilation test (endothelium-dependent vasomotricity). Their were also automatically and non-invasively monitored in their systolic (S) and diastolic (D) BP over the 24-h period in order to confirm that they were not hypertensive. RESULTS: Eight of the investigated normotensives were found to show an ED. A significantly higher daily mean level as well as a more prominent nychtohemeral variability in SBP and DBP 24-h values were observed in the normotensives with ED as compared to the normotensives without ED. The higher BP regimen in the normotensives with ED was found to maintain a circadian rhythm. However, a significant amplification the second harmonic component, with a 12-h period, was observed. The different structure of the BP 24-h pattern in the normotensives with ED was confirmed by the detection of additional ultradian components at the linear-in-period spectral analysis. CONCLUSIONS: The present study documented a significant elevation of BP 24-h values in normotensives with ED that is the reflex of consistent changes in the frequency organization of the BP circadian pattern. The elevation of BP regimen suggests that the ED is associated with vasopressant effects even in normotensives. Such a condition of higher BP in normotensives with ED can be regarded as a status of "pre-hypertension".

Adult↗
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[Circadian rhythm of serum levo-carnitine: parameters].

OBJECTIVE: The present study investigates the circadian rhythm (CR) of levo-carnitine (L-c) in systemic venous blood, in order to detect rhythmometric parameters that can be used for programming an eventual chronoterapy with such a molecule. MATERIALS AND METHODS: The L-c CR was investigated in 10 clinically healthy subjects (5 M; 5 F; mean age: 26.02 +/- 1.11 yrs), who were diurnally active and nocturnally resting. Blood samples were taken at 06:00; 08:00; 12:00; 18:00; 20:00; 24:00, not juxtaposed to breakfast, lunch and dinner. The serum concentrations of L-c were assayed via a spectrophotometric method. RESULTS: A nychtohemeral variability in circulating levels of L-c was observed, with a peak in the afternoon. Such a intradiem variability was validated to have the properties of a significant CR (MESOR = 33.37 mumol/l with a SEM of 1.19 mumol/l; amplitude = 6.31 mumol/l with 95%CL ranging from 3.58 mumol/l to 9.69 mumol/l; acrophase at 15:52 h:min with 95%CL ranging from 13:28 h:min to 17:00 h:min). CONCLUSIONS: It is important to remark that the validation of a CR for the systemic serum levels of L-c was obtained in diurnally-active/nocturnally resting subjects. Such validated rhythmometric properties are parameters that can be used for programming an eventual chronotherapy, considering that the molecule L-c is used for treating its various types of primary and secondary deficiency.

Adult↗
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Higher blood pressure load (baric impact) in normotensives with endothelial dysfunction: a paraphysiological status of "pre-hypertension".

PURPOSE: The present study investigated the blood pressure (BP) load (L), namely Baric Impact (BI), in normotensives with and without endothelial dysfunction (ED). The aim was to detect baric differences supporting the thesis that the ED is associated with vasopressant effects that are responsible for a paraphysiological condition of higher BP (pre-hypertension) even in normotensives. MATERIALS AND METHODS: Thirty-eight normotensives were investigated in their endothelium-dependent vasomotricity by mean of the non-invasive post-ischemic brachial artery vasodilation test. Additionally, their underwent a non-invasive ambulatory (A) BP monitoring (M) over the 24-h span in order to confirm that they were not hypertensive. The ABPM served also to compute the systolic (S) and diastolic (D) BI. RESULTS: The ED was detected in eight normotensives of the investigated group. These cases with ED were found to show a significantly higher SBI and DBI as compared to the normotensives without ED. CONCLUSIONS: The significant elevation of the SBI and DBI in normotensives with ED is an evidence convincing that a dysfunctional endothelium is responsible for vasopressant effects that cause a paraphysiological status of "pre-hypertension".

Adult↗