Obesidade, hipertensão arterial e suas influências sobre a massa e função do ventrículo esquerdo

In order to evaluate the influences of obesity and hypertension on left ventricular mass (LVM), we studied 121 women stratified into 4 groups: normotensive non-obeses (n = 25), hypertensive non-obeses (n = 30), normotensive obeses (n = 24) and hypertensive obeses (n = 42) according to their anthropometric and echocardiographic parameters and ambulatory blood pressure monitoring (ABPM). Hypertensive obeses showed higher LVM than the other groups - normotensive non-obeses, hypertensive non-obeses and normotensive obeses (167 ± 38.8 vs. 113 ± 26.4; vs. 133 ± 26.5; vs. 132 ± 29.2g; respectively, p < 0.05) ond higher diameter of left atrium (LA) as compared to the non-obese groups with or without hypertension (36 ± 4.3 vs. 33 ±5.1; vs. 35 ± 3.9mm; p < 0.05, respectively). Normotensive obese patients showed similar LVM to the hypertensive non-obeses (133 ± 26.5 vs. 132 ± 29.5g; NS) and increased LA as compared to the normotensive non-obeses (35 ± 3.9 vs. 31 ± 4.6mm; p < 0.05). A correlation between the waist circumference and waist-to-hip ratio with the blood pressure levels obtained by the ABPM, as well as between these measurements with the echocardiographic parameters, which reflect cardiac mass; body mass index only showed to be correlated to the LA diameter. The adjustment of LVM by the height instead of body surface resulted in an increase on the prevalence of LV hypertrophy among obese patients (10.6 vs. 36.7%, p < 0.01), but not among non-obeses. Lack of nocturnal blood pressure fall assessed by ABPM (non-dipper) was more prevalent among obese patients with or without hypertension; however, non-dipper hypertensive obese patients did not differ from the dippers according to the LVM. Our data demonstrate that obesity associated to hypertension provoke a more pronounced increase in LVM as compared to the condition separately. We also conclude that obese patients showed increased frequency of abnormal 24-hr blood pressure profile, characterized by decreased tensional drop during sleep.Para avaliar as influências da obesidade e da hipertensão sobre a massa de ventrículo esquerdo (MVE), estudamos 121 mulheres divididas em 4 grupos: não-obesas normotensas (n = 25), não-obesas hipertensas (n = 30), obesas normotensas (n = 24) e obesas hipertensas (n = 42) quanto a parâmetros antropométricos, ecocardiográficos e de monitorização ambulatorial da pressão arterial (MAPA). As pacientes obesas hipertensas apresentaram maior MVE que os outros grupos - não-obesas normotensas, não-obesas hipertensas e obesas normotensas (167 ± 38,8 vs. 113 + 26,4; vs. 133 ± 26,5; vs. 132 ± 29,2g; p < 0,05, respectivamente) e maior diâmetro de átrio esquerdo (AE) quando comparadas aos grupos de não-obesas, tanto normotensas como hipertensas (36 ± 4,3 vs. 33 ± 5,1; vs. 35 ± 3,9mm; p < 0,05, respectivamente). Obesas normotensas apresentaram MVE similar à do grupo não-obesas hipertensas (133 ± 26,5 vs. 132 ± 29,5g; NS) e aumento de AE quando comparadas às não-obesas normotensas (35 ± 3,9 vs. 31 ± 4,6mm; p < 0,05). Detectou-se correlação entre a circunferência da cintura e a razão cintura-quadril com os níveis pressóricos à MAPA, assim como entre estas medidas e parâmetros ecocardiográficos que avaliam a massa cardíaca; o índice de massa corporal só se correlacionou ao diâmetro do AE. A correção da MVE pela altura ao invés da superfície corpórea aumentou a prevalência de hipertrofia de VE nas obesas (10,6 vs. 36,7%, p < 0,01), mas não nas não-obesas. Ausência de descenso noturno da pressão arterial sistólica à MAPA (non-dipper) foi mais prevalente nas pacientes obesas, hipertensas ou não; entretanto, as obesas hipertensas non-dippers não diferiram das dippers quanto à MVE. Nossos dados demonstram que a obesidade associada à hipertensão aumenta a MVE de modo mais importante do que as condições isoladamente. Concluímos, ainda, que pacientes obesas também apresentam alta freqüência de alterações do ritmo da pressão arterial de 24 horas, caracterizada por menor queda pressórica durante o sono.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Preventiva Departamento de MedicinaUNIFESP, Depto. de Medicina Preventiva Depto. de MedicinaSciEL

An Evaluation of Self-Measured Blood Pressure in a Study With a Calcium-Channel Antagonist Versus a β-Blocker

In recent years self-measurement of blood pressure at home has gained increasing importance but there have been only a few studies comparing casual, ambulatory, and self-measured blood pressure determinations during a single clinical trial. We therefore compared treatment-induced blood pressure-reductions in a double-blind, placebo-controlled, parallel study design with a single morning dose of either 10 mg bisoprolol (n = 26) or 20 mg nitrendi-pine (n = 27) with casual blood pressure readings in the morning before the dose, ambulatory 24-h monitoring, and self-recorded measurements in the morning before the dose and in the evening. Mean reductions for systolic and diastolic blood pressure after 4 weeks of therapy were significantly greater for bisoprolol than for nitrendipine. The treatment-induced blood pressure reductions were most pronounced as assessed by casual readings but showed good agreement between casual, ambulatory, and self-measured blood pressure for group comparisons. In some patients, however, marked individual differences between the three methods were observed. Correlation coefficients between ambulatory and self-measured blood pressure were 0.4 for systolic blood pressure (P < .05) and 0.6 for diastolic blood pressure (P < .0005). Under the conditions of this parallel study design and the usual statistical risks, a difference of 5 mm Hg in diastolic blood pressure can be detected in 118 patients at the clinic, in 70 patients if ambulatory blood pressure is used, or in 56 patients if self-measured blood pressure is used. In conclusion, bisoprolol was more effective over 24 h than nitrendipine at the doses studied. Furthermore, self-measured blood pressure was suitable for monitoring 24-h efficacy of the two antihypertensive drugs under investigation. Finally, self-measured blood pressure can substantially improve the sensitivity of hypertension trials in comparison to casual readings and therefore reduce the number of patients included. Am J Hypertens 1992;5:154-16

24 hour-ambulatory blood pressure and heart rate profiles in diagnosing orthostatic hypotension in Parkinson’s disease and Multiple System Atrophy

Background:24-hour ambulatory blood pressure and heart rate monitoring (24hr-ABPM) can provide vital information on circadian blood pressure (BP) profiles, which are commonly abnormal in Parkinson’s disease with and without autonomic failure (PD+AF and PD) and multiple system atrophy (MSA). 24hr-ABPM has not been directly compared between these disorders regarding cardiovascular autonomic function. We aim to determine the usefulness of 24hr-ABPM with diary compared to Head-up Tilting (HUT) in diagnosing orthostatic hypotension (OH) in these patients. Methods: 74 patients (23 MSA,18 PD+AF,33 PD) underwent cardiovascular autonomic screening followed by 24hr-ABPM with diary. Standing tests were included during 24hr-ABPM. The sensitivity and specificity in detecting OH from the 24hr-ABPM standing test were compared with HUT. Results: There was no difference in OH during HUT between MSA and PD+AF (p>0.05). MSA and PD+AF had a higher proportion of abnormal BP circadian rhythms compared to PD (p0.05). Patients were divided into groups with (OH+) and without OH (OH-) on HUT. Using the standing test during 24hr-ABPM, a SBP fall of >20 mmHg showed a sensitivity and specificity of 82% and 100 % (AUC 0.91, 95% CI 0.84-0.98) in differentiating OH+ from OH-, respectively. Conclusions:PD+AF and MSA patients had similar circadian BP patterns suggesting that autonomic dysfunction influences abnormal BP circadian patterns similarly in these disorders. The higher sensitivity and specificity in detecting OH using a SBP fall of >20 mmHg compared to a DBP fall of >10 mmHg during standing test supports its usefulness to assess autonomic function in MSA and PD

Genome-wide association study of nocturnal blood pressure dipping in hypertensive patients

Abstract Background Reduced nocturnal fall (non-dipping) of blood pressure (BP) is a predictor of cardiovascular target organ damage. No genome-wide association studies (GWAS) on BP dipping have been previously reported. Methods To study genetic variation affecting BP dipping, we conducted a GWAS in Genetics of Drug Responsiveness in Essential Hypertension (GENRES) cohort (n = 204) using the mean night-to-day BP ratio from up to four ambulatory BP recordings conducted on placebo. Associations with P < 1 × 10− 5 were further tested in two independent cohorts: Haemodynamics in Primary and Secondary Hypertension (DYNAMIC) (n = 183) and Dietary, Lifestyle and Genetic determinants of Obesity and Metabolic Syndrome (DILGOM) (n = 180). We also tested the genome-wide significant single nucleotide polymorphism (SNP) for association with left ventricular hypertrophy in GENRES. Results In GENRES GWAS, rs4905794 near BCL11B achieved genome-wide significance (β = − 4.8%, P = 9.6 × 10− 9 for systolic and β = − 4.3%, P = 2.2 × 10− 6 for diastolic night-to-day BP ratio). Seven additional SNPs in five loci had P values < 1 × 10− 5. The association of rs4905794 did not significantly replicate, even though in DYNAMIC the effect was in the same direction (β = − 0.8%, P = 0.4 for systolic and β = − 1.6%, P = 0.13 for diastolic night-to-day BP ratio). In GENRES, the associations remained significant even during administration of four different antihypertensive drugs. In separate analysis in GENRES, rs4905794 was associated with echocardiographic left ventricular mass (β = − 7.6 g/m2, P = 0.02). Conclusions rs4905794 near BCL11B showed evidence for association with nocturnal BP dipping. It also associated with left ventricular mass in GENRES. Combined with earlier data, our results provide support to the idea that BCL11B could play a role in cardiovascular pathophysiology

Adaptive mechanisms of homeostasis disorders

The ability to preserve a permanent level of internal environment in a human organism, against internal and external factors, which could breach the consistency, can be define as homeostasis. Scientific proven influence on the homeostasis has the periodicity of biological processes, which is also called circadian rhythm. The effect of circadian rhythm is also to see in the functioning of autonomic nervous system and cardiovascular system. Sleep deprivation is an example of how the disorders in circadian rhythm could have the influence on the homeostasis

Chronic kidney disease prevalence and ambulatory blood pressure profile in healthy HIV positive subjects pre and post anti-retroviral therapy

Introduction: Few studies have been done in South Africa to establish the extent of chronic kidney disease (CKD) in stable outpatients infected with the human immunodeficiency virus (HIV). Both HIV and the anteretroviral therapy (ART) used to treat HIV have been associated with abnormal metabolic profile, increased cardiovascular risk and renal disease1,2,3. Hypertension has been found to be common in HIV infected individuals, in European and American cohorts, with a prevalence ranging from 13- 34%2. Nocturnal blood pressure (BP) is superior to daytime or office BP as a predictor of cardiovascular disease4. However, the relationship between circadian BP patterns, measured via ambulatory blood pressure (ABP) monitoring, and HIV has never been documented in the South African HIV infected population. Individuals with an abnormal diurnal rhythm and a blunted nocturnal decline in systolic BP (SBP), i.e. ≤ 10%, are referred to as 'non- dippers' and have the highest risk of cardiovascular complications4. HIV itself has been associated with a non- dipping status and may play a role in the HIV related increase in cardiovascular risk5

The relevance of arterial blood pressure in the management of glaucoma progression: a systematic review

Background Glaucoma is one of the leading causes of global blindness and is expected to co-occur more frequently with vascular morbidities in the upcoming years, as both are aging-related diseases. Yet, the pathogenesis of glaucoma is not entirely elucidated and the interplay between intraocular pressure, arterial blood pressure and ocular perfusion pressure is poorly understood. Objective This systematic review aims to provide clinicians with the latest literature regarding the management of arterial blood pressure in glaucoma patients. Methods A systematic search was performed in Medline, Embase, Web of Science and Cochrane Library. Articles written in English assessing the influence of arterial blood pressure and systemic antihypertensive treatment of glaucoma and its management were eligible for inclusion. Additional studies were identified by revising references included in selected articles. Results 80 articles were included in this systemic review. A bimodal relation between blood pressure and glaucoma progression was found. Both high and low blood pressure increase the risk of glaucoma. Glaucoma progression was, possibly via ocular perfusion pressure variation, strongly associated with nocturnal dipping and high variability in the blood pressure over 24-hours. Conclusions We concluded that systemic blood pressure level associates with glaucomatous damage and provided recommendations for the management and study of arterial blood pressure in glaucoma. Prospective clinical trials are needed to further support these recommendations

Reproducibility of blood pressure dipping: Relation to day-to-day variability in sleep quality

Previous studies of the reproducibility of blood pressure (BP) dipping have yielded inconsistent results. Few have examined factors that may influence dayto-day differences in dipping

Genome-wide association study of nocturnal blood pressure dipping in hypertensive patients

Background: Reduced nocturnal fall (non-dipping) of blood pressure (BP) is a predictor of cardiovascular target organ damage. No genome-wide association studies (GWAS) on BP dipping have been previously reported.Methods: To study genetic variation affecting BP dipping, we conducted a GWAS in Genetics of Drug Responsiveness in Essential Hypertension (GENRES) cohort (n = 204) using the mean night-to-day BP ratio from up to four ambulatory BP recordings conducted on placebo. Associations with P< 1 x 10(-5) were further tested in two independent cohorts: Haemodynamics in Primary and Secondary Hypertension (DYNAMIC) (n = 183) and Dietary, Lifestyle and Genetic determinants of Obesity and Metabolic Syndrome (DILGOM) (n = 180). We also tested the genome-wide significant single nucleotide polymorphism (SNP) for association with left ventricular hypertrophy in GENRES.Results: In GENRES GWAS, rs4905794 near BCL11B achieved genome-wide significance (beta = - 4.8%, P = 9.6 x 10(-9) for systolic and beta = - 4.3%, P = 2.2 x 10(-6) for diastolic night-to-day BP ratio). Seven additional SNPs in five loci had P values < 1 x 10(-5). The association of rs4905794 did not significantly replicate, even though in DYNAMIC the effect was in the same direction (beta = - 0.8%, P = 0.4 for systolic and beta = - 1.6%, P = 0.13 for diastolic night-to-day BP ratio). In GENRES, the associations remained significant even during administration of four different antihypertensive drugs. In separate analysis in GENRES, rs4905794 was associated with echocardiographic left ventricular mass (beta = -7.6 g/m(2), P = 0.02).Conclusions: rs4905794 near BCL11B showed evidence for association with nocturnal BP dipping. It also associated with left ventricular mass in GENRES. Combined with earlier data, our results provide support to the idea that BCL11B could play a role in cardiovascular pathophysiology

Validierung eines neuartigen Blutdruck Messgerätes entsprechend den Vorgaben des International Protocol der European Society of Hypertension: Das Citizen CH-461 C

Die Messserie, die dieser Arbeit zugrunde liegt, hatte zum Ziel eine hinreichende Genauigkeit und Praktikabilität des Blutdruckmessgerätes Citizen CH - 461 C nachzuweisen und somit das Gerät auf seine Eignung im klinischen Alltag zu testen. Zur Validierung und somit auch zur Standardisierung solcher neuartigen Blutdruckmessgeräte hat die „Working Group on Blood Pressure Monitoring“ der „European Society of Hypertension“ ein Protokoll, das so genannte International Protocol (IP), herausgegeben, um so die erforderliche Prüfung neuartiger Geräte zu erleichtern. Die Untersuchungen, die dieser vorliegenden Arbeit zugrunde liegen, prüften entsprechend den Vorgaben des IPs das neuartige Gerät Citizen CH-461C auf seine Messgenauigkeit und somit auf seine entsprechenden Eignungen für den klinischen Einsatz. An 33 Probanden wurden von zwei trainierten Beobachtern jeweils neun sequentielle Blutdruckmessungen am gleichen Arm vorgenommen, wobei fünf Messungen mit einer geeichten Quecksilber Säule als Standard im Wechsel zu vier Messungen mit dem zu testenden Gerät gemessen worden sind. Die resultierenden Differenzen zwischen den Werten des Gerätes und denen der Quecksilber Säule wurden zur weiteren Evaluation verwendet. Es kann schlussgefolgert werden, dass das getestete Gerät Citizen CH - 461 C für den klinischen Einsatz empfohlen werden kann