This study examined relationships between 24-hour ambulatory BP and components of the insulin resistance syndrome, and investigated the prognostic significance of 24-hour BP for cardiovascular morbidity in a longitudinal population-based study of 70-year-old men. The findings indicated, that a reduced nocturnal BP fall, nondipping, was a marker of increased risk primarily in subjects with diabetes. A low body mass index and a more favourable serum fatty acid composition at age 50 predicted the development of white-coat as opposed to sustained hypertension over 20 years. Furthermore, cross-sectionally determined hypertensive organ damage at age 70 was detected in sustained hypertensive but not in white-coat hypertensive subjects. In a prospective analysis, 24-hour ambulatory pulse pressure and systolic BP variability at age 70 were strong predictors of subsequent cardiovascular morbidity, independently of office BP and other established risk factors. Isolated ambulatory hypertension, defined as having a normal office BP but increased daytime ambulatory BP, was associated with a significantly increased incidence of cardiovascular events during follow-up. Hypertension constitutes part of the insulin resistance syndrome, and is a common and powerful risk factor for cardiovascular disease in elderly. Blood pressure (BP) measured with 24-hour ambulatory monitoring gives however more detailed information and may be a better estimate of the true BP than conventional office BP. In summary, these data provide further knowledge of 24-hour ambulatory BP and associated metabolic risk profile, and suggest that the prognostic value of 24-hour ambulatory BP is superior to conventional BP in an elderly population.

Objectives: To assess the role of ambulatory blood pressure monitoring in the diagnosis of hypertension in general practice. Background: Hypertension is usually diagnosed by casual office blood pressure readings. However, ambulatory blood pressure monitoring has shown that a significant proportion of patients diagnosed as hypertension in fact do not have hypertension. Method: Sixty four Indian patients diagnosed as having mild to moderate hypertension by casual measurements were subjected to a twenty four hour ambulatory blood pressure monitoring. A blood pressure load of >35% was classified as true hypertension and < 35% as white coat hypertension. White coat hypertensives were compared to the hypertensive group with respect to various demographic characteristics, and to correlate ambulatory blood pressure monitoring and casual blood pressure readings. Results: A prevalence of 23.44% white coat hypertension was found. In addition, the demographic profile of such patients show a preponderance of non-obese females (73.33%), the majority of whom are on concomitant medication (60%). A poor correlation was found between the casual office blood pressure readings and the twenty four hour ambulatory blood pressure readings in the white coat hypertensives as compared to the hypertensive group. Conclusion: White coat hypertension is common in patients diagnosed as having mild to moderate hypertension by casual blood pressure readings. There are no reliable clinical indicators to identify patients with white coat hypertension. Ambulatory blood pressure monitoring has been shown to be a useful method for differentiating white coat hypertensives from true hypertensives. / Thesis (M.Med)-University of Natal, 1997.

Peripheral arterial disease (PAD) is a common manifestation of stenoses and occlusions of the arteries of the lower extremities. Clinically, PAD is an important effect on functional ability, and quality of life because symptomatic patients are typically able to walk less than one to three blocks before rest is required.The double product break point (DPBP), also defined as the oxygen consumption at which the first portion of nonlinear increase in rate pressure product (systolic blood pressure X heart rate) begins has been identified to determine the anaerobic threshold during exercise test. The purpose of this study was to determine whether the DPBP could be detected in patients with PAD during a symptom-limited GXT on the motor-driven treadmill. Six male subjects (68.2 ± 6.5 yrs) with history of diagnosis of PAD participated in this study. Double product (DP) was assessed every 15 seconds during the test via the Kyokko Bussan CM-4001 automated blood pressure unit. The DPBP and VT were determined visually by three blinded observers. The mean values of Peak V02 and maximal heart rate were 19.4 ± 5.8 (ml/kg/min) and 130 ± 13 (bpm), respectively. In 4 of the six exercise tests in the present study, the DPBP and the VT were determined. The mean V02 at the DPBP and the VT were 15.7 ± 2.6 ml/kg/min and 14.2 ± 0.6 ml/kg/min, corresponding to 73 ± 7.2 and 74.5 ± 5.4 % respectively. In 3 of the six exercise tests both of the DPBP and VT were determined. The Mean V02 at the DPBP and VT were 14.6 ± 1.8 and 14.3 ± 0.7, respectively. The difference of the mean VO2 at the VT and DPBP was -.0.33 ml/kg/min.In conclusion, the results of the present study suggest that the DPBP can be identified and used as a useful marker to determine the functional performance in PAD patients. Walking time or distance measurement depends on the patient's perception of the pain. Thus, this study provides an objective way to appraise the functional performance and therapeutic results obtained from the exercise training in PAD patients, and provides a reference for exercise prescription for this population. / School of Physical Education

Motivation: Ischemic heart disease is the eighth leading cause of death in an African population. Silent ischemia can be defined as an ischemic episode without associated pain. The clinical significance of silent ischemia is growing and can now be considered as a risk factor in the development of coronary disease. Hypertension and associated risk factors, hypercholesterolemia and diabetes are associated with silent ischemia. Other factors such as higher pulse pressure, double product, heart rate and higher carotid intima-media thickness are also associated with silent ischemia. Urbanisation is rising in South-Africa. This new lifestyle is associated with several risk factors including: poor diets, lower physical activity levels, hypertension and increased smoking and alcohol abuse. The prevalence of stroke is high among Africans, which can be due to a higher prevalence of hypertension, diabetes and obesity. Purpose: The purpose of this study was to determine the associations between silent ischemia and cardiovascular function in African men. The focus fell on hypertension and associated risk factors, higher total cholesterol levels, and increased pulse pressure, heart rate and sub-clinical atherosclerosis. vi Methodology: This study constituted a population study in the North-West province carried out on urbanized African male teachers aged between 20-60 years. The SABPA (Sympathetic activity and Ambulatory Blood Pressure in Africans) sub-study consisted of a total of 80 African male volunteers. The Cardiotens apparatus was placed on each participant on the first morning. This apparatus took ambulatory blood pressure measurements as well as Electrocardiogram measurements. Hereafter, participants continued with their normal work day until 1700. After an overnight stay at the Metabolic unit of the North-West University Potchefstroom campus, the apparatus was removed at 0600. During statistical analyses, the African males were divided into groups of participants with silent ischemia (SI) and those without silent ischemia (nSI), as determined by the ambulatory electrocardiogram. Statistical analyses were performed by means of the Statistica version 10 software program. Results: In comparison with the nSI men, the SI showed the following: above normal high sensitivity C-reactive protein and glucose, higher ambulatory blood pressure, heart rate, pulse pressure, resting ST-segment depression and carotid intima-media thickness. Multiple regression analyses indicated that ambulatory silent ischemia is associated with sub-clinical atherosclerosis, possibly increasing their stroke risk. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2012.

Motivation: Ischemic heart disease is the eighth leading cause of death in an African population. Silent ischemia can be defined as an ischemic episode without associated pain. The clinical significance of silent ischemia is growing and can now be considered as a risk factor in the development of coronary disease. Hypertension and associated risk factors, hypercholesterolemia and diabetes are associated with silent ischemia. Other factors such as higher pulse pressure, double product, heart rate and higher carotid intima-media thickness are also associated with silent ischemia. Urbanisation is rising in South-Africa. This new lifestyle is associated with several risk factors including: poor diets, lower physical activity levels, hypertension and increased smoking and alcohol abuse. The prevalence of stroke is high among Africans, which can be due to a higher prevalence of hypertension, diabetes and obesity. Purpose: The purpose of this study was to determine the associations between silent ischemia and cardiovascular function in African men. The focus fell on hypertension and associated risk factors, higher total cholesterol levels, and increased pulse pressure, heart rate and sub-clinical atherosclerosis. vi Methodology: This study constituted a population study in the North-West province carried out on urbanized African male teachers aged between 20-60 years. The SABPA (Sympathetic activity and Ambulatory Blood Pressure in Africans) sub-study consisted of a total of 80 African male volunteers. The Cardiotens apparatus was placed on each participant on the first morning. This apparatus took ambulatory blood pressure measurements as well as Electrocardiogram measurements. Hereafter, participants continued with their normal work day until 1700. After an overnight stay at the Metabolic unit of the North-West University Potchefstroom campus, the apparatus was removed at 0600. During statistical analyses, the African males were divided into groups of participants with silent ischemia (SI) and those without silent ischemia (nSI), as determined by the ambulatory electrocardiogram. Statistical analyses were performed by means of the Statistica version 10 software program. Results: In comparison with the nSI men, the SI showed the following: above normal high sensitivity C-reactive protein and glucose, higher ambulatory blood pressure, heart rate, pulse pressure, resting ST-segment depression and carotid intima-media thickness. Multiple regression analyses indicated that ambulatory silent ischemia is associated with sub-clinical atherosclerosis, possibly increasing their stroke risk. / Thesis (M.Sc. (Physiology))--North-West University, Potchefstroom Campus, 2012.

Previous research has reported positive associations between anger, perceived stress and blood pressure. These associations have largely been based on cross-sectional data and a small number of longitudinal works. Using a prospective longitudinal cohort design, this study more directly tested the relationships between anger, perceived stress and blood pressure by using a psychological therapeutic intervention (mindfulness-based stress reduction) to manipulate anger and perceived stress. Anger and perceived stress were in turn evaluated for association with blood pressure. Despite improvements in psychosocial functioning and reductions in blood pressure, findings from this study failed to demonstrate an association between change in anger or perceived stress with change in daytime or 24-hour ambulatory blood pressure. A model where these variables interact indirectly via stress coping mechanisms or health behaviours may be the linking mechanism in this study. Results from this thesis have contributed evidence to a divided field dominated by cross-sectional research.

Previous research has reported positive associations between anger, perceived stress and blood pressure. These associations have largely been based on cross-sectional data and a small number of longitudinal works. Using a prospective longitudinal cohort design, this study more directly tested the relationships between anger, perceived stress and blood pressure by using a psychological therapeutic intervention (mindfulness-based stress reduction) to manipulate anger and perceived stress. Anger and perceived stress were in turn evaluated for association with blood pressure. Despite improvements in psychosocial functioning and reductions in blood pressure, findings from this study failed to demonstrate an association between change in anger or perceived stress with change in daytime or 24-hour ambulatory blood pressure. A model where these variables interact indirectly via stress coping mechanisms or health behaviours may be the linking mechanism in this study. Results from this thesis have contributed evidence to a divided field dominated by cross-sectional research.

Objetivo: Investigar o efeito de se distinguir a pressão arterial noturna da pressão arterial no sono pelo registro simultâneo da monitorização ambulatorial da pressão arterial e da polissonografia. Métodos: Recrutaram-se 36 pacientes, 29 homens e 7 mulheres, com suspeita de síndrome das apnéias e hipopnéias obstrutivas do sono (SAHOS), encaminhados à clínica do sono para investigação diagnóstica e que concordaram usar o monitor ambulatorial de pressão arterial (MAPA) Spacelabs 90207 ABP durante a polissonografia (PSG). A média de idade dos indivíduos era 45 ± 11 anos; o índice de massa corporal (IMC), 30,8 ± 5,4 Kg/m2; o índice de apnéias e hipopnéias, 35 ± 29 AH/h. Um microfone acoplado ao monitor ambulatorial de PA registrou os sons característicos de sua atividade em um canal da polissonografia e permitiu determinar, de modo eletrográfico, se a PA foi medida em sono (e-sono) ou vigília (e-vigília).Resultados: Os pacientes encontravam-se dormindo durante (média+DP) 61+24% (variando de 0 a 100%), das 14+1 medidas de pressão arterial durante a noite. Leituras de pressão sistólica e diastólica na MAPA foram significativamente maiores durante o evigília (121 + 12 / 73 + 9 mm Hg) que durante o total do período noturno (119 + 11 / 70 + 8 mmHg) e e-sono (116 + 13 / 68 + 9 mm Hg). Baseado nas medidas do período noturno, 22 pacientes (61%) tinham hipertensão noturna; baseado nas medidas do período de e-sono, 12 pacientes tinham hipertensão noturna (33%; qui-quadrado= 5,54; p= 0,018). Um modelo de regressão linear múltipla mostrou que a percentagem de medidas feitas durante o e-sono foi a única variável que explicou significantemente a diferença entre os valores de PA noturna e PA em e-sono, controlando para gênero, idade, IMC, IAH, e SaO2 mínima. Conclusão: Durante a MAPA as leituras de PA noturnas são mais altas que as leituras durante e-sono. / Objective: Investigate the effect of distinguishing nighttime and sleep on nocturnal blood pressure results in ambulatory blood pressure monitoring (ABPM). Methods: We recruited 36 patients, 28 male, with suspected OSAHS attending a sleep clinic for diagnostic polysomnography (PSG) and who agreed to wear a Spacelabs 90207 ABP monitor during PSG. Their mean age was 45±11 years; body mass index (BMI), 30.8±5.4 kg/m2; apnea-hypopnea index (AHI), 35±29 AH/h; 13 had history of hypertension. A microphone attached to the ABP monitor recorded its sounds in the polygraph and allowed to classify each ABPM measurement as being made in electrographically-determined wake (e-wake) or sleep state (e-sleep). Results: Patients were asleep during (mean±SD) 61±24% (range 0 to 100%) of the 14±1 nighttime BP measurements. Systolic and diastolic ABPM readings were significantly higher during e-wake (121±12 / 73±9 mm Hg) than during total nighttime (119±11/70±8 m Hg) and e-sleep (116±13 / 68±9 mm Hg). Based on nighttime measurements 22 patients (61%) had nocturnal hypertension. Based on measurements made during e-sleep, nocturnal hypertension was diagnosed in 12 patients (33%; chisquare= 5.54; p= 0.018). A multiple linear regression model showed that the percentage of measurements made in e-sleep was the only variable that significantly explained the difference between nighttime and e-sleep BP figures, when controlling for gender, age, BMI, AHI, and lowest SaO2. Conclusion: During ABPM, nighttime BP readings are higher than during e-sleep and this changes dipping and nocturnal hypertension classification.

Introdução: Parte dos efeitos benéficos das estatinas sobre a prevenção de eventos cardiovasculares podem ser atribuídos a efeitos pleiotrópicos, entre eles, a redução da pressão arterial (PA). Objetivo: Avaliar o efeito da administração de sinvastatina sobre a pressão arterial aferida por monitorização ambulatorial de pressão arterial (MAPA-24h). Métodos: Em um ensaio clínico duplo-cego em paralelo, 79 pacientes hipertensos sem indicação formal para o uso de estatinas foram randomizados para receber 40mg de sinvastatina (n=40) ou placebo (n=39) durante o período da manhã. Dados clínicos, laboratoriais e de MAPA-24h foram coletados no início e após oito semanas de seguimento. A amostra constituiu-se preponderantemente de mulheres brancas com sobrepeso e 80% usava dois ou mais anti-hipertensivos. Resultados: Constatou-se uma redução da pressão arterial no grupo sinvastatina. Houve uma diferença significativa no delta de variação da pressão diastólica (PAD) de 24h após ajuste para pressões basais (2,8 mmHg; IC95%: 0,4-5,1, P=0,02). Os valores correspondentes para a pressão arterial sistólica (PAS) e PAD diurno foram: 4,2 mmHg; (IC95%: 0,1-8,4, P=0,04) e 3,1mmHg (IC95%: 0,4-5,9, P=0,02). Conclusão: A administração de 40mg de sinvastatina durante o período da manhã resulta em redução significativa da PAS e PAD durante o dia cuja magnitude pode ter repercussão clínica. Considera-se que, parte dos benefícios das estatinas na prevenção primária ou secundária de eventos cardiovasculares, demonstrados em importantes ensaios clínicos, podem estar relacionados ao seu efeito na redução da pressão arterial. / Background: Part of the beneficial effects of statins on the prevention of cardiovascular events can be attributed to pleiotropic effects, including reduction of blood pressure (BP). Objective: To evaluate the effect of simvastatin on BP measured by ambulatory blood pressure monitoring (ABPM-24h). Methods: In a double-blind parallel clinical trial 79 hypertensive patients without a formal indication for statin therapy were randomized to receive 40 mg of simvastatin (n = 40) or placebo (n = 39) during the morning. Clinical, laboratory and ABPM-24h data were collected at the baseline and after 8 weeks of follow-up. The sample consisted mainly of white overweight women and 80% used two or more antihypertensive drugs. Results: There was a significant reduction in 24-h diastolic blood pressure (24h-DBP) in the simvastatin group. The ABPM δ-value between the groups after adjustment for baseline BP was 2.8 mmHg (95% CI: 0.4 to 5.1, P = 0.02). The corresponding values for daytime systolic blood pressure (SBP) and daytime DBP were 4.2 mmHg (95% CI: 0.1 to 8.4; P = 0.04) and 3.1 mmHg (95% CI: 0.4 to 5.9; P = 0.02). Conclusion: The administration of 40 mg of simvastatin during the morning period resulted in a significant reduction in daytime SBP and DBP. This effect may have clinical impact. Some of the benefits of statins in primary or secondary prevention of cardiovascular events demonstrated in large clinical trials may be related to its effect in reducing blood pressure.

Observou-se a prevalência crescente das doenças cardiovasculares nos dias de hoje e o acometimento cada vez maior da população pediátrica. O objetivo principal no presente estudo foi verificar a associação entre a pressão arterial ambulatorial e variáveis antropométricas em 34 pré-adolescentes e adolescentes na faixa de idade entre 9 e 17 anos de ambos os sexos. Analisamos também se a prática regular de exercícios físicos beneficia, em relação as variáveis concernentes à pressão arterial, este grupo de indivíduos. A avaliação da pressão arterial foi realizada através da monitorização ambulatorial da pressão arterial durante 24 horas por ser uma forma de avaliação que oferece maior reprodutibilidade dos valores e maior detalhamento sobre o comportamento da pressão arterial nos diferentes períodos do dia. Foi utilizada a estatística descritiva para apresentar os resultados obtidos, a correlação de Pearson e Spearman para avaliar as associações entre as variáveis e a regressão linear múltipla para controlar os fatores de confusão e avaliar os preditores das variáveis de desfecho. Conclui-se que o índice de massa corporal se associa diretamente com a pressão arterial ambulatorial sistólica diurna e com a pressão arterial ambulatorial sistólica de 24 horas, independentemente de outras variáveis antropométricas. A estatura e o índice de massa corporal se associam diretamente à pressão arterial ambulatorial sistólica diurna e a pressão arterial ambulatorial média diurna neste grupo de pré-adolescentes e adolescentes. A relação cintura/quadril é significativamente menor naqueles que praticam exercícios físicos regularmente. / We observed the growing incidence and prevalence of cardiovascular diseases nowadays in the pediatric population. The aim of this study was to verify the association betwen ambulatory blood pressure and anthropometrical variables in 34 pre-teenagers and teenagers, ranging from 9 to 17 years old both male and female. We also analyzed if the frequent practice of exercices helps group of individuals in relation to this blood pressures variables. The blood pressure was evaluated by 24-h ambulatory blood pressure monitoring since this offers a better values reproducibility and more details about blood pressure behavior in diferences times of the day. We used descriptive statistics to present the final results and applied Pearson and Spearman tests to evaluated the association betwen the variables. Finally, applied the multivariated regression analisys to control the confusion factors. Our conclusion was that the body mass index is directed associated with the daytime sistolic ambulatory blood pressure and the 24-h sistolic ambulatory blood pressure independently from any other anthropometric variable. The height and the body mass index are directly associated to the daytime sistolic ambulatory blood pressure and the daytime average ambulatory blood pressure in this group. The waist-to-hip relation is smaller in the individuals that practice exercices regularly.