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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
471

Avaliação da pressão arterial antes e após paratireoidectomia por hiperparatireoidismo primário / Arterial blood pressure monitoring before and after parathyroidectomy for primary hyperaparathyroidism

Ledo Mazzei Massoni Neto 13 March 2018 (has links)
INTRODUÇÃO: O hiperparatireoidismo primário (HPTP) é uma doença endócrina cuja prevalência aumentou muito nas últimas décadas. Descobriu-se grande contingente de portadores de formas leves e assintomáticos. Foi observado que esses pacientes apresentam alta morbidade e mortalidade por causas cardiovasculares. O estudo da pressão arterial revelou alta incidência de hipertensão arterial e descenso atenuado. A reversibilidade destes efeitos após a paratireoidectomia, entretanto é controversa. MÉTODO: Estudo prospectivo observacional com pacientes portadores de HPTP esporádico submetidos a paratireoidectomia para verificar as alterações dos parâmetros relativos à pressão arterial após a resolução do HPTP. Os pacientes realizaram monitorização ambulatorial de 24 horas da pressão arterial antes e após cirurgia curativa para HPTP, no 3º pós-operatório, 3 meses, 6 meses e 12 meses. RESULTADOS: Em 7 casos (6 mulheres, idade média 65,7 anos), houve aumento do descenso da pressão arterial sistólica e diastólica. As médias (desvio padrão) da pressão arterial sistólica (PAS) e da pressão arterial diastólica (PAD) foram 124,0mmHg (10,6) e 78,7mmHg (10,4). Não foi observada alteração significativa após a operação. As médias de PAS foram 129,4 mmHg (3 PO), 130,4 mmHg (3 meses) 125,4 mmHg(6 meses) e 131,1 mmHg (12 meses). As médias de PAD foram 73,7 mmHg (3 PO), 78,6 mmHg 75,4 mmHg (6 meses) e 78,0 MMhg (12 meses). Por outro lado, o descenso noturno sistólico e diastólico da pressão arterial apresentaram melhora significativa aos 6 meses e sustentada aos 12 meses. As médias do descenso da PAS foram de 4,3% no pré-operatório; 1,2% no 3o pós-operatório; 10,7% após 6 meses (p=0,002) e de 10,5% 12 meses depois da operação (p=0,008). As médias do descenso da PAD foram de 7,1% no pré-operatório, 4,0% no 3o pós-operatório, 13,3%; aos 6 meses (p=0,02) e de 14,7% depois de 12 meses da paratireoidectomia (p=0,03). CONCLUSÃO: A paratireoidectomia melhora o descenso noturno da pressão arterial em pacientes com HPTP esporádico / INTRODUCTION: Primary hyperparathyroidism is an endocrine disease and its prevalence has increased dramatically in the last decades. There is a great number of individuals with mild or asymptomatic forms of the disease. There is evidence of cardiovascular complications and mortality in these patients. The study of blood pressure showed high prevalence of hypertension and decreased dipping. The reversibility of these effects on blood pressure after curative parathyroidectomy is debatable. METHODS: Prospective study to evaluate the changes in blood pressure measurements of patients undergoing curative parathyroidectomy for sporadic PHPT with 24-hour ambulatory blood pressure monitoring before (PRE) and after curative surgery, during hospital stay (PO3), three months (3 mo), six months (6 mo) and at 12 months (12 mo). RESULTS: In 7 cases (6 female, mean age 65.7 years), there was an improvement of the nocturnal dipping of the systolic and diastolic arterial pressure. Mean (standard deviation) preoperative Systolic Blood Pressure (SBP) and Diastolic Blood Pressure (DBP) were 124.0 mmHg (10.6) and 78.7 mmHg (10.4). No significant change in blood pressure was observed after the operation. Mean SBP values were 129.4 mmHg (PO 3), 130.4 mmHg (3 mo), 125.4 mmHg (6 mo) and 131.1 mmHg (12 mo). Mean DBP measures were 73.7 mmHg (PO 3), 78.6 mmHg (3 mo), 75.4 mmHg (6 mo) and 78.0 mmHg (12 mo). Conversely, nocturnal systolic and diastolic dipping presented a small nonsignificant decrease immediately after the operation, but a statistically significant and sustained improvement at 6 months and 12 months. Mean systolic nocturnal dipping was 4.3% (PRE), 1.2% (PO 3); 10.7% (6 mo) (p=0,002) and 10.5% (12 mo) (p=0.008). Mean diastolic nocturnal dipping was 7.1% (PRE), 4.0% (PO 3), 13.3% (6 mo) (p=0,01) and 14.7% (12 mo) (p=0.03). Conclusions: In sporadic PHPT, parathyroidectomy improves nocturnal dipping of blood pressure
472

Estudo de validação do aparelho automático para medida de pressão arterial dixtal DX 2020 em unidade de terapia intensiva adulto = Validation study of automatic apparatus for measuring blood pressure dixtal DX 2020 in adult intensive care unit / Validation study of automatic apparatus for measuring blood pressure dixtal DX 2020 in adult intensive care unit

Gothardo, Ana Carolina Lopes Ottoni, 1979- 07 December 2012 (has links)
Orientador: José Luiz Tatagiba Lamas / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-20T22:31:22Z (GMT). No. of bitstreams: 1 Gothardo_AnaCarolinaLopesOttoni_M.pdf: 3169615 bytes, checksum: da99c78d906df92371167a9e0c7c0502 (MD5) Previous issue date: 2012 / Resumo: A medição da pressão arterial em setores de emergência e cuidados intensivos é um procedimento utilizado para avaliar com rapidez a condição do paciente e direcionar a conduta terapêutica. Devido aos cuidados peculiares existentes na Unidade de Terapia Intensiva, a monitorização hemodinâmica desses pacientes é realizada por monitores automáticos multiparamétricos o que torna esse procedimento mais fácil e rápido. Esse tipo de monitorização consiste no controle de parâmetros como eletrocardiograma, pressão arterial (direta ou indireta), saturação de oxigênio, frequência cardíaca, temperatura, frequência respiratória, capnografia e débito cardíaco. Para garantir a precisão e o desempenho desses aparelhos automáticos, estes devem passar por testes rigorosos a fim de validá-los para seu uso clinico. Assim torna-se necessário aferir sua confiabilidade usando protocolos adequados, reconhecidos por sociedades cientificas. Este estudo tem como objetivo avaliar a confiabilidade do monitor multiparamétrico Dixtal® DX 2020 na medida da pressão arterial em adultos de acordo com o Protocolo Internacional, proposto pela European Society of Hypertension (ESH). Para o desenvolvimento desse estudo foram realizadas medidas de pressão arterial em 33 sujeitos, com uso do esfigmomanômetro de coluna de mercúrio, da marca Unitec e o aparelho automático Dixtal® DX 2020 com número de série 81303876. Nove medidas sequenciais foram realizadas no braço, alternando entre o esfigmomanômetro de mercúrio e o automático em teste, conforme Protocolo Internacional, além da obtenção do eletrocardiograma. O protocolo estabelece a necessidade de atender duas exigências. Na primeira exigência o aparelho foi reprovado na PAS em todas as faixas. Das 99 diferenças obtidas, apenas 43 se situaram na faixa de 0 a 5 mmHg (de 73 exigidas), 69 medidas na faixa de 0 a 10 mmHg (de 87 exigidas) e 81 entre 0 e 15 mmHg (de 96 exigidas). Na PAD também foi reprovado em todas as faixas, obtendo 29 diferenças entre 0 e 5 mmHg, 56 entre 0 e 10 mmHg e 71 entre 0 e 15 mmHg, sendo exigidas 65, 81 e 93, respectivamente. Na segunda exigência pelo menos 24 sujeitos deveriam ter duas de suas três comparações na faixa de 0 a 5 mmHg, o que aconteceu somente com 16 sujeitos na sistólica e 9 na diastólica. Além disso, no máximo três poderiam ter todas suas comparações acima de 5 mmHg e isso aconteceu com 10 sujeitos na sistólica e 17 na diastólica. O aparelho não atendeu os critérios estabelecidos para a pressão sistólica (PAS) e pressão diastólica (PAD) em nenhuma das duas exigências, não sendo recomendado para o uso clínico de acordo com este protocolo. Cuidados com a validação dos aparelhos deveriam ocorrer com maior frequência no sentido de garantir às pessoas em cuidados intensivos valores fidedignos. É importante ressaltar que este estudo refere-se especificamente ao módulo de verificação da PA do monitor em estudo, não sendo possível tirar a mesma conclusão para suas outras funções / Abstract: The measurement of blood pressure in emergency departments and intensive care is a procedure used to quickly assess the patient's condition and direct the therapeutic approach. Due to the peculiar care existing in the intensive care unit, hemodynamic monitoring of patients is performed by automated multiparameter monitors which makes this procedure easier and faster. This type of monitoring controls parameters such as electrocardiogram, blood pressure (direct or indirect), oxygen saturation, heart rate, temperature, respiratory rate, capnography and cardiac output. To ensure accuracy and performance of these automated devices, they must undergo rigorous testing to validate them for clinical use. So it becomes necessary to assess its reliability using appropriate protocols, recognized by scientific societies. This study aims to evaluate the reliability of the multiparameter monitor Dixtal® DX 2020 on blood pressure determination in adults according to the International Protocol, proposed by the European Society of Hypertension (ESH). For the development of this study blood pressure was measured in 33 subjects, using a Unitec® mercury sphygmomanometer, and the automatic drive Dixtal® DX 2020, serial number 81303876. Nine sequential measurements were performed in the arm, alternating between the mercury sphygmomanometer and the automatic unit in test, as determined by the International Protocol, and the electrocardiogram. The protocol establishes the need to meet two requirements. In the first requirement, the device failed SBP measurements in all ranges. Among the 99 obtained differences, only 43 were located in the range 0-5 mm Hg (73 required), 69 in the range 0-10 mm Hg (87 required) and 81 between 0 and 15 mmHg (96 required). Regarding DBP, the device also failed in all ranges, obtaining 29 differences between 0 and 5 mmHg, 56 from 0 to 10 and 71 between 0 and 15 mmHg( 65, 81 and 93 required respectively). To pass in the second requirement at least 24 subjects should have two of their three comparisons in the range 0-5 mmHg, which happened with only 16 subjects in systolic and 9 in diastolic. Furthermore, at most three could have all their comparisons over 5 mmHg and this happened to 10 subjects in the systolic and 17 diastolic. The unit did not meet the criteria for systolic (SBP) and diastolic blood pressure (DBP) in any of the two requirements and it is not recommended for clinical use in accordance with this protocol. Importantly, this study specifically refers to the BP scanning module of the monitor in study, it is not possible to draw the same conclusion for its other functions / Mestrado / Enfermagem e Trabalho / Mestra em Ciências da Saúde
473

The effect of maternal malaria during pregnancy on birth size, early childhood growth and blood pressure in Nigerian children

Ayoola, Omolola January 2011 (has links)
Background: In Nigeria, there is an escalating incidence of hypertension, its complications and other cardiovascular risks, likely to have their origins in early life. Malaria is still hyperendemic, with pregnant women at increased risk, with associated consequences of maternal anemia and high rates of delivering low birth-weight babies. Aims and Hypothesis: In this study, we have tested the hypothesis that malaria in pregnancy will not only enhance the risk of small birth size and poor infant growth, but will also generate higher blood pressures in infancy and beyond. We also tested the hypothesis that metabolic markers in pregnant mothers affected by malaria would relate to infant birth size. Thus the aims of this project were: 1) to define relationships between the type of malaria exposure and birth size, 2) to characterize the association between maternal and cord metabolic biomarkers and birth size on the background of prenatal malaria exposure and 3) to examine the effect prenatal malaria exposure on first year growth and whether higher blood pressure (BP) is generated. Methods: Healthy pregnant women were recruited and followed at Adeoyo Maternity Hospital, Ibadan. Anthropometric, BP, and biomarkers (lipids, glucose, insulin and TNFα) measurements were obtained in the mothers at booking. Birth size and growth at 3 and 12 months along with biomarkers (as above) and IGF-I measures in cord blood were assessed in the infants. Blood films for malaria parasites were taken throughout pregnancy including delivery and in all babies. Women were grouped to distinguish between the timing of malaria parasitaemia (either during pregnancy only or during pregnancy and at delivery) and the severity of malaria infection (low vs high parasite load). At birth, 436 mother-baby pairs were measured. 467 maternal samples were obtained for metabolic profile and 187 cord blood samples. 318 babies were all followed from birth to 3 and 12 months. Results: Malaria parasitaemia was found in 48% of the women, associated with younger maternal age, being primigravid and a lower haematocrit. Babies of mothers with high parasitaemia through pregnancy had the smallest birth growth parameters compared with those without malaria (weight, length, and head circumference were smaller by 300g, 1.1cm and 0.7cm respectively, all p≤0.005) but their systolic BP (SBP) and diastolic BP (DBP) adjusted for weight were higher than those with low parasitaemia by 1.7 and 1.4 mmHg/kg respectively. SBPs were lowest in babies of mothers with malaria at delivery implying an acute effect on the babies’ circulation. Mothers with malaria had significantly lower lipids (except triglycerides) but higher TNFa, effect not seen in cord blood. Cord IGF-I was significantly lower in babies whose mothers had malaria. Significant determinants of birth size were maternal total cholesterol, LDL- cholesterol, insulin, malarial status and cord insulin and IGF-I. Babies exposed to maternal malaria remained smaller at 1 year, most marked in boys, whose SBP adjusted for weight at 3 and 12 months was higher than those not exposed. Change in SBP over the first year was greater in boys than girls while the change in girls was greater in those exposed to maternal malaria than those not exposed (18.7 vs 12.7 mmHg, 95% CI 1-11, p=0.02). 11% of boys ( > twice expected) had BP >95th percentile (hypertensive, US criteria) of whom 68% had maternal malaria exposure. Gender, maternal malaria exposure and weight change were all independently associated with increased change in BP to 1 year. Conclusion: Intrauterine exposure to malaria appears not only to have an important impact on birth size but also gender-dependent effects on growth and changes in infant BP. These findings have potential implications for cardiovascular health in sub-Saharan Africa and may contribute to the global burden of hypertension.
474

The risk of metabolic syndrome as a result of lifestyle among Ellisras rural young adults : Ellisras longitudinal study

Sekgala, M. D. January 2019 (has links)
Thesis (M. Sc. (Physiology)) --University of Limpopo, 2019 / Introduction: There is an increased trend in the prevalence of hypertension in children and adolescents in African countries. There are complications in diagnosing hypertension in children and adolescents due to the variation of blood pressure (BP) values with age, gender and height. The progression of the health transition with non-communicable diseases (NCDs) adds significantly to the disease burden, despite infectious diseases and undernutrition remaining persistent in both low and middle-income countries. Metabolic syndrome (MetS) is a global problem associated with the clustering of several cardiovascular risk factors. South African evidence suggests an upsurge of NCDs amidst the existence of communicable diseases (CDs) such as HIV/AIDS and tuberculosis. Moreover, NCDs and CDs in the country are influenced by socio-demographic factors; and thus tend to be more prominent in certain segments of the population. Aim and Objectives: The aim of this study was to perform blood pressure to height ratio and to determine lifestyle risk factors associated with metabolic syndrome among the Ellisras rural population aged 6-30 years, who are part of the ELS. Methods and materials: The current study is based on secondary data analysis of the Ellisras Longitudinal Study (ELS) and was conducted in two phases. Phase 1 included data analysis of all the participants in the ELS. This sample included a total number of 9002 children and adolescents (4678 boys and 4324 girls), aged 6-17 years. Parents or guardians provided written informed consent. Phase 2 consisted of biochemical analysis from a subsample of participants in the ELS. The subsample included 624 participants (306 males and 318 females) aged 18-30 years at the time the study was conducted. All participants underwent a series of anthropometric measurements (waist circumference and height) according to the standard of the International Society for the Advancement of Kinanthropometry (ISAK). The waist circumference (WC) measurements were taken to the nearest 0.1 cm, using a soft measuring tape. Metabolic syndrome was defined according to the International Diabetes Federation (IDF) criteria. Metabolic syndrome risk factors included total cholesterol (TCHOL), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), elevated fasting blood glucose (FBG), elevated blood pressure (BP) and high waist circumference (WC). A dietary intake questionnaire was also administered to each participant and self‑administered questionnaire was used to collect data on lifestyle factors, including smoking and alcohol intake. Dietary intake variables used in the linear regression method were log transformed prior to analysis because of their skewed distribution. Receiver-operating characteristic (ROC) curve was used to assess the accuracy of BPHR to screen children with prehypertension and hypertension. The optimal systolic BPHR (SBPHR) and diastolic BPHR (DBPHR) cut-off points for hypertension were determined. Sensitivity/specificity, positive predictive values and negative predictive values were calculated. Results: The optimal thresholds for defining prehypertension was 0.77 in children aged 6-10 years and 0.73 in adolescents aged between 11 and 17 years for systolic BPHR and 0.55 in children and 0.53 in adolescents for diastolic BPHR, respectively. The corresponding values for hypertension stage 1 were 0.76 and 0.73 for SBPHR and 0.50 and 0.58 for DBPHR, respectively. The BPHR is an accurate tool for screening elevated BP in Ellisras children aged 6-17 years. This can help to prevent the misclassification of children and adolescent hypertension. Furthermore, this tool can be used to screen children before the development of prehypertension and hypertension. Moreover, it can be used to manage hypertension in Ellisras children, ultimately reducing the risks of developing hypertension and associated cardiovascular disease in adulthood. Overall, the prevalence of metS was 23.1% (8.6% males and 36.8% females). Females appeared to have higher mean values for WC, FBG, TCHOL and LDL-C than males (82.14, 5.62, 4.62 and 2.97, respectively). The only significant gender difference observed was on WC (p<0.001). Males on the other hand had higher mean values for HDL-C, TG, SBP and DBP than females (1.20, 1.06, 125.91 and 71.44, respectively). The only significant difference observed in this case was on SBP (p<0.001). No significant age group differences were observed in all the metabolic risk factors with the exception of DBP where the older (25-30 years) participants presented with high SBP than the younger age group (18-24 years) (70.96 mmHg vs 68.78 mmHg, p<0.05). While, majority of females had significantly high WC, elevated total cholesterol and LDL-C, and reduced HDL-C; majority of males had elevated BP, SBP and DBP. No significant age and gender differences were observed on dietary intake. However, according to the linear regression analysis, no association between log total energy, log added sugar, log SFA and log MUFA with metabolic risk factors. There was a low and negative significant association between log fibre with SBP and DBP (β:-0.004, p=0.003 and β:-0.004, p=0.046), respectively, crude. After adjusting for the potential confounding factors, log fibre was also associated with FBG (β:-0.028, p=0.046). Log PUFAs was inversely associated with FBG, HDL-C and SBP crude. Log trans fatty acids was inversely associated with WC, HDL-C and SBP crude. Both log PUFAs and log trans fatty acids were not associated with any metabolic risk factors after adjusting for potential cofounding factors. Log protein was inversely associated with SBP both crude and adjusted for potential cofounding factors. On predicting the actual risk using the logistic regression analysis, participants who had high dietary energy intake were significantly less likely to present with larger WC, low HDL-C and high LDL-C (OR: 0.250 95%CI [0.161;0.389], OR: 0.306 95%CI [0.220;0.425] and OR: 0.583 95%CI [0.418;0.812], respectively), but more likely to presents with elevated FBG, high TCHOL, high TG and hypertension (OR: 1.01 95%CI [0.735;1.386], OR: 1.039 95%CI [0.575;1.337], OR: 1.186 95%CI [0.695;2.023], OR: 5.205 95%CI [3.156;8.585], respectively) crude. After adjusting for age, gender, smoking and alcohol status, high energy intake was more likely to increase two times high the large WC and elevated FBG among study participants (OR: 2.766 95%CI [0.863;3.477] and OR: 2.227 95%CI [1.051;3.328], respectively). Furthermore, low dietary fibre intake was nearly four times more likely to increase the low HDL-C, crude (OR: 3.864 95%CI [1.067;13.988]) crude. Those participants who consumed high trans fats were more likely to present with high FBG (OR:1.424 95%CI [0.985;2.060]), but less likely to present with LDL-C (OR: 0.540 95%CI [0.321;0.906]) crude. However, after adding potential cofounding factors, participants with high fatty acid were less likely to present with high FBG (OR: 0.672 95%CI [0.441;1.023]). Conclusions: MetS is prevalent in young adults in Ellisras and is differentiated by age and gender with more females at an increased rate by virtue of their body size status, reduced HDL-C, elevated FBG and high LDL-C and the diet they consume that is in most cases high energy, more carbohydrates, high added sugar and SFA. Therefore, identifying groups that are at an increased risk and those that are in their early stages of MetS will help improve and prevent the increase of the metS in the future. These results have high policy implications. KEY CONCEPTS Metabolic syndrome; risk factors; blood pressure; blood pressure to height ratio; cardiovascular disease; dietary intake; rural South African.
475

Remote Home Blood Pressure Monitoring for Management of Hypertension

Oliphant, Kathleen M. 26 April 2021 (has links)
No description available.
476

En jämförelse av tre olika metoder för blodtrycksmätning vid vila / Comparison of three different methods for blood pressure measurements at rest

Björsson, Linnéa January 2023 (has links)
Introduktion: Blodtryck är en livsviktig funktion som bidrar till syretillförseln till kroppens olika organ. Blodtryck går att mäta och är en viktig indikation på det kardiovaskulära systemets funktion. Det finns olika metoder att mäta blodtryck, bland annat auskultatoriskt, automatiskt och med hjälp av Dopplerteknik. Syftet var att jämföra de tre olika metoderna för att se om det förelåg en signifikant skillnad mellan metoderna.   Material och metod: Studien bestod av 30 deltagare. Studiedeltagaren vilade i tio minuter före första blodtrycksmätningen, därefter mättes deras blodtryck i en slumpad ordning med auskultatorisk, automatisk och med Dopplermetod. För att kontrollera om det förelåg en statistisk signifikant skillnad användes en variansanalys (ANOVA) och ett parat t-test.   Resultat och slutats: Det förelåg ingen signifikant skillnad mellan de systoliska blodtrycken. Däremot mellan de diastoliska trycken registrerat med den auskultatoriska och automatiska metoden förelåg det en signifikant skillnad, men den anses inte ha en klinisk betydelse. / Introduction: Blood pressure is a vital function that contributes to the supply of oxygen to the body’s various organs. Blood pressure can be measured and is an important indicator of the cardiovascular system function. There are different methods to measure blood pressure, these are, for example auscultatory, automatic and with the help of a Doppler technique. The aim was to compare the three different methods and see if there was a significant difference between them.   Material and method: The study consisted of 30 participants. The participant rested for ten minutes before the first examination and then their blood pressure was measured in a random order by the three methods: auscultatory, automatic and the Doppler method. To process the collected data an analysis of variance test (ANOVA) and a paired t-test were used.   Results and conclusion: There were no significant difference between the systolic blood pressures. In contrast, there was a difference between the diastolic blood pressures registered with the auscultatory and automatic methods, but this was not considered to be of clinical significance.
477

Associations between specific measures of adiposity and high blood pressure in black South African women / Maretha Doubell

Doubell, Maretha January 2015 (has links)
Introduction: The World Health Organisation (WHO) defines overweight and obesity as a condition in which an abnormal or excessive fat accumulation exists to an extent in which health and well-being are impaired. The most recent South African National Health and Nutrition Examination Survey (SANHANES) reported that the prevalence of overweight and obesity, according to body mass index (BMI) classification, in all South African women was significantly higher than in men (24.8% and 39.2% compared to 20.1% and 10.6% for women and men, respectively). Blood pressure is often increased in obese patients and is probably the most common co-morbidity associated with obesity. Currently approximately one third (30.4%) of the adult South African population has hypertension. Hypertension is responsible for a significant percentage of the high rates of cardiovascular disease and stroke in South Africa. Limited South African data are available regarding the agreement between the measures of adiposity, including BMI, waist circumference (WC) and percentage body fat (%BF), and the association with high blood pressure. Measures of adiposity were found in previous research to be ethnicity, age and gender specific. Measuring %BF to classify adiposity takes body composition into account and is a more physiological measurement of obesity than BMI. Objective: This study aimed to investigate the agreement between adiposity classified by BMI categories and %BF cut-off points, and the association between the different measures of adiposity and high blood pressure. Method: A representative sample of black women (n=435), aged 29 years to 65 years from Ikageng in the North West Province of South Africa were included in this cross-sectional epidemiological study. Socio-demographic questionnaires were completed. Pregnancy and HIV tests were performed and those with positive test results or those who declined HIV testing were excluded. Weight and height were measured and BMI was calculated. WC, %BF using dual-energy X-ray absorptiometry (DXA), and blood pressure were measured. Results: The prevalence of overweight (BMI 25.0 kg/m² – 29.9 kg/m²) was 24.4% and obesity (BMI ≥ 30kg/m²) was 52.4%. High blood pressure was found to be present in more than two thirds of the study participants (68.5%). In this study BMI, WC and %BF as measures of adiposity were significantly correlated. There were significant agreements between combined overweight/obesity that was defined by %BF (≥35.8% 29-45 years; ≥37.7% ≥50 years) and BMI ≥ 25kg/m² (ᵡ²=199.0, p<0.0001; κ=0.68, p<0.0001), and between the presence of high %BF and obesity only, that was defined by BMI ≥ 30 kg/m² (ᵡ²=129.1, p<0.0001; κ=0.48, p<0.0001). The effect size of the agreement between the WHO BMI category for combined overweight/obesity and %BF cut-off points according to the kappa value of κ=0.68 was substantial (κ range 0.61-0.80). The effect size of the agreement between the WHO BMI category for obesity only and %BF cut-off points according to the kappa value of κ=0.48 was moderate (κ range 0.41-0.60). No association was found between high blood pressure and BMI categorised combined overweight/obesity (ᵡ²=3.19; p=0.74), but a significant association was found between high blood pressure and BMI categorised obesity only (ᵡ²=4.10; p=0.043). A significantly increased odds ratio (OR) of high blood pressure existed in the obesity BMI category (OR=1.52; p=0.045) as opposed to the overweight/obesity BMI category (OR=1.51; p=0.075). There were significant associations between high blood pressure and WC ≥ 80cm (ᵡ²=10.9; p=0.001; OR=2.08; p=0.001), WC ≥ 92cm (ᵡ²=20.1; p<0.0001; OR=1.79; p=0.011) and %BF above the age-specific cut-off points (ᵡ²=6.61; p=0.010; OR=1.70; p=0.011). Discussion and conclusion: This study found that in a sample of black urban South African women significant agreements existed between adiposity defined by %BF cut-off points for combined overweight/obesity and both WHO BMI categorised combined overweight/obesity (BMI ≥ 25 kg/m2) and obesity only (BMI ≥ 30 kg/m2), respectively. A stronger agreement was found between WHO categorised combined overweight/obesity and %BF. Furthermore, this study concluded that the BMI category according to the WHO cut-off point for overweight/obesity had insufficient sensitivity to detect the presence of high blood pressure, and that the BMI category according to the WHO cut-off point for obesity alone could detect the presence of high blood pressure. The WHO BMI classification for obesity, in contrast to the WHO BMI classification for combined overweight/obesity, is therefore appropriate to classify these black South African women at increased risk for high blood pressure. The WC and %BF cut-off points used which were specific to ethnicity, age and gender, had significant associations with high blood pressure and have good capacity to detect high blood pressure. In this study abdominal obesity as defined by the South African cut-off point of WC ≥ 92 cm had a stronger association with high blood pressure, than the international cut-off point (WC ≥ 80 cm). The South African cut-off point is, therefore, more appropriate to screen black South African women for increased risk for high blood pressure. The study therefore concluded that a stronger agreement was found between WHO categorised combined overweight/obesity and %BF than with obesity only (BMI ≥ 30 kg/m2). To ensure consistency and accuracy, and to take body composition into consideration, it is recommended that, where possible, in clinical practice the appropriate WC and %BF cut-off points together with BMI categories should be used as measures of adiposity for diagnosis of overweight and obesity and to screen or detect an increased risk for high blood pressure. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2015
478

Brain derived neurotrophic factor and structural vascular disease in black Africans : the SABPA study / Alwyn Johannes Smith

Smith, Alwyn Johannes January 2014 (has links)
Motivation - Brain-derived neurotrophic factor (BDNF) is a protein complex, synthesised and secreted mainly by the central nervous system and is involved in neuronal maintenance. Research suggests that BDNF is implicated in various neurological and psychiatric diseases, while recent evidence suggests a role for the neurotrophin on the periphery as well. Indeed, the specific functional role of BDNF and its action mechanism in the cardiovascular system, especially in that of Africans, is yet to be determined. The cardiovascular health profile of black South Africans is a major concern as research has shown that this group suffers from an array of cardiovascular risk factors that may result in organ damage. Sub-clinical atherosclerosis or structural endothelial dysfunction contributes to ever-increasing morbidity and mortality in the world. However, no studies regarding the associations between BDNF and structural vascular disease have been undertaken relating to black African participants. Objectives - The objective of this study was to determine whether BDNF is associated with changes in ambulatory blood pressure (BP) and whether a relationship between BDNF and structural endothelial dysfunction exists in black African male and female participants, determined by cross sectional wall area (CSWA) and albumin:creatinine ratio (ACR). Methodology - The study included 172 black African teachers (82 males and 90 females) who were employed by the Kenneth Kaunda Education district of the North-West Province, South Africa. Ambulatory blood pressure recordings were obtained with the use of a Meditech CE120 CardioTens ® apparatus. Blood pressure readings were measured at 30 min intervals during the day and 60 min intervals during the night. Anthropometric measurements were performed in triplicate by registered level II anthropometrists according to standardised procedures. A high-resolution ultrasound scan with carotid intima-media thickness (CIMT) images from at least two optimal angles of the left and right common carotid artery were obtained using a SonoSite Micromaxx ultrasound system. The lumen diameter between the near and far wall of the lumen-intima interface and the averages of both the left and right common carotid arteries were calculated. Subsequently, the carotid cross-sectional wall area (CSWA) was calculated. Participants, who fasted overnight, provided eight-hour blood and urine samples to determine serum BDNF and metabolic markers, for example, hyperglycaemia (HbA1c) and gamma glutamyl transferase (GGT). Urinary albumin and creatinine levels were determined by means of a turbidimetric method with the use of a Unicel DXC 800 analyser from Beckman and Coulter (Germany) and expressed as a ratio between albumin and creatinine (ACR). BDNF median split x Gender interaction effects for structural ED justified stratification of BDNF into low and high (≤ / > 1.37 ng/ml) gender groups. Results and Conclusion - On average, male participants were overweight (BMI 25-30kg/m2) and abused more alcohol.21 African men revealed a vulnerable cardiometabolic profile with values exceeding cut–points (European Society of Hypertension). These men demonstrated increased acute and chronic glucose (HbA1c) levels indicating a pre-diabetic state; as well as a disturbed lipid profile with lower HdL and increased triglycerides. Overall BDNF levels were lower than reference ranges (6.97 – 42.6 ng/ml). The men revealed mean lower BDNF levels, ambulatory BP values exceeding guideline cut-points (ambulatory SBP > 130mmHg; DBP > 80mmHg) as well as a hypertensive state compared to their female counterparts. Pertaining to structural endothelial dysfunction, the mean ACR value in men exceeded normal laboratory values (< 3.5mg/mmol). The African women displayed an obese state with low grade inflammation (CRP, 12.27 ± 11.67mg/l). A single two-way ANCOVA interaction on main effects (BDNF median split x Gender) demonstrated significant interaction for CIMTf [F (1,164); 3.99, p=0.05] and cholesterol [F (1,164); 4.12, p=0.05]. Therefore, a median split approach was followed which stratified gender groups into lower (≤ 1.37 ng/ml) and higher BDNF levels (>1.37 ng/ml). The low BDNF men revealed higher cholesterol than the high BDNF group, independent of BMI and age. Only the low BDNF women indicated significantly higher values for structural vascular markers (p< 0.05) than the high BDNF female group. In conclusion, we accept our hypothesis, as hypertrophic remodelling of the carotid artery was associated with lower BDNF levels. This may imply attenuated or possibly down-regulated BDNF levels acting as a compensatory mechanism for the mean higher BP levels. In women, metabolic risk and hypertrophic remodelling were evident within higher circulating levels of BDNF, underpinning different underlying mechanisms for impaired neurotrophin health in men and women. Novel findings of BDNF revealed the impact of central neural regulation on the circulatory system, which may contribute to cardiometabolic risk in Africans. / MSc (Physiology), North-West University, Potchefstroom Campus, 2014
479

Associations between specific measures of adiposity and high blood pressure in black South African women / Maretha Doubell

Doubell, Maretha January 2015 (has links)
Introduction: The World Health Organisation (WHO) defines overweight and obesity as a condition in which an abnormal or excessive fat accumulation exists to an extent in which health and well-being are impaired. The most recent South African National Health and Nutrition Examination Survey (SANHANES) reported that the prevalence of overweight and obesity, according to body mass index (BMI) classification, in all South African women was significantly higher than in men (24.8% and 39.2% compared to 20.1% and 10.6% for women and men, respectively). Blood pressure is often increased in obese patients and is probably the most common co-morbidity associated with obesity. Currently approximately one third (30.4%) of the adult South African population has hypertension. Hypertension is responsible for a significant percentage of the high rates of cardiovascular disease and stroke in South Africa. Limited South African data are available regarding the agreement between the measures of adiposity, including BMI, waist circumference (WC) and percentage body fat (%BF), and the association with high blood pressure. Measures of adiposity were found in previous research to be ethnicity, age and gender specific. Measuring %BF to classify adiposity takes body composition into account and is a more physiological measurement of obesity than BMI. Objective: This study aimed to investigate the agreement between adiposity classified by BMI categories and %BF cut-off points, and the association between the different measures of adiposity and high blood pressure. Method: A representative sample of black women (n=435), aged 29 years to 65 years from Ikageng in the North West Province of South Africa were included in this cross-sectional epidemiological study. Socio-demographic questionnaires were completed. Pregnancy and HIV tests were performed and those with positive test results or those who declined HIV testing were excluded. Weight and height were measured and BMI was calculated. WC, %BF using dual-energy X-ray absorptiometry (DXA), and blood pressure were measured. Results: The prevalence of overweight (BMI 25.0 kg/m² – 29.9 kg/m²) was 24.4% and obesity (BMI ≥ 30kg/m²) was 52.4%. High blood pressure was found to be present in more than two thirds of the study participants (68.5%). In this study BMI, WC and %BF as measures of adiposity were significantly correlated. There were significant agreements between combined overweight/obesity that was defined by %BF (≥35.8% 29-45 years; ≥37.7% ≥50 years) and BMI ≥ 25kg/m² (ᵡ²=199.0, p<0.0001; κ=0.68, p<0.0001), and between the presence of high %BF and obesity only, that was defined by BMI ≥ 30 kg/m² (ᵡ²=129.1, p<0.0001; κ=0.48, p<0.0001). The effect size of the agreement between the WHO BMI category for combined overweight/obesity and %BF cut-off points according to the kappa value of κ=0.68 was substantial (κ range 0.61-0.80). The effect size of the agreement between the WHO BMI category for obesity only and %BF cut-off points according to the kappa value of κ=0.48 was moderate (κ range 0.41-0.60). No association was found between high blood pressure and BMI categorised combined overweight/obesity (ᵡ²=3.19; p=0.74), but a significant association was found between high blood pressure and BMI categorised obesity only (ᵡ²=4.10; p=0.043). A significantly increased odds ratio (OR) of high blood pressure existed in the obesity BMI category (OR=1.52; p=0.045) as opposed to the overweight/obesity BMI category (OR=1.51; p=0.075). There were significant associations between high blood pressure and WC ≥ 80cm (ᵡ²=10.9; p=0.001; OR=2.08; p=0.001), WC ≥ 92cm (ᵡ²=20.1; p<0.0001; OR=1.79; p=0.011) and %BF above the age-specific cut-off points (ᵡ²=6.61; p=0.010; OR=1.70; p=0.011). Discussion and conclusion: This study found that in a sample of black urban South African women significant agreements existed between adiposity defined by %BF cut-off points for combined overweight/obesity and both WHO BMI categorised combined overweight/obesity (BMI ≥ 25 kg/m2) and obesity only (BMI ≥ 30 kg/m2), respectively. A stronger agreement was found between WHO categorised combined overweight/obesity and %BF. Furthermore, this study concluded that the BMI category according to the WHO cut-off point for overweight/obesity had insufficient sensitivity to detect the presence of high blood pressure, and that the BMI category according to the WHO cut-off point for obesity alone could detect the presence of high blood pressure. The WHO BMI classification for obesity, in contrast to the WHO BMI classification for combined overweight/obesity, is therefore appropriate to classify these black South African women at increased risk for high blood pressure. The WC and %BF cut-off points used which were specific to ethnicity, age and gender, had significant associations with high blood pressure and have good capacity to detect high blood pressure. In this study abdominal obesity as defined by the South African cut-off point of WC ≥ 92 cm had a stronger association with high blood pressure, than the international cut-off point (WC ≥ 80 cm). The South African cut-off point is, therefore, more appropriate to screen black South African women for increased risk for high blood pressure. The study therefore concluded that a stronger agreement was found between WHO categorised combined overweight/obesity and %BF than with obesity only (BMI ≥ 30 kg/m2). To ensure consistency and accuracy, and to take body composition into consideration, it is recommended that, where possible, in clinical practice the appropriate WC and %BF cut-off points together with BMI categories should be used as measures of adiposity for diagnosis of overweight and obesity and to screen or detect an increased risk for high blood pressure. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2015
480

Brain derived neurotrophic factor and structural vascular disease in black Africans : the SABPA study / Alwyn Johannes Smith

Smith, Alwyn Johannes January 2014 (has links)
Motivation - Brain-derived neurotrophic factor (BDNF) is a protein complex, synthesised and secreted mainly by the central nervous system and is involved in neuronal maintenance. Research suggests that BDNF is implicated in various neurological and psychiatric diseases, while recent evidence suggests a role for the neurotrophin on the periphery as well. Indeed, the specific functional role of BDNF and its action mechanism in the cardiovascular system, especially in that of Africans, is yet to be determined. The cardiovascular health profile of black South Africans is a major concern as research has shown that this group suffers from an array of cardiovascular risk factors that may result in organ damage. Sub-clinical atherosclerosis or structural endothelial dysfunction contributes to ever-increasing morbidity and mortality in the world. However, no studies regarding the associations between BDNF and structural vascular disease have been undertaken relating to black African participants. Objectives - The objective of this study was to determine whether BDNF is associated with changes in ambulatory blood pressure (BP) and whether a relationship between BDNF and structural endothelial dysfunction exists in black African male and female participants, determined by cross sectional wall area (CSWA) and albumin:creatinine ratio (ACR). Methodology - The study included 172 black African teachers (82 males and 90 females) who were employed by the Kenneth Kaunda Education district of the North-West Province, South Africa. Ambulatory blood pressure recordings were obtained with the use of a Meditech CE120 CardioTens ® apparatus. Blood pressure readings were measured at 30 min intervals during the day and 60 min intervals during the night. Anthropometric measurements were performed in triplicate by registered level II anthropometrists according to standardised procedures. A high-resolution ultrasound scan with carotid intima-media thickness (CIMT) images from at least two optimal angles of the left and right common carotid artery were obtained using a SonoSite Micromaxx ultrasound system. The lumen diameter between the near and far wall of the lumen-intima interface and the averages of both the left and right common carotid arteries were calculated. Subsequently, the carotid cross-sectional wall area (CSWA) was calculated. Participants, who fasted overnight, provided eight-hour blood and urine samples to determine serum BDNF and metabolic markers, for example, hyperglycaemia (HbA1c) and gamma glutamyl transferase (GGT). Urinary albumin and creatinine levels were determined by means of a turbidimetric method with the use of a Unicel DXC 800 analyser from Beckman and Coulter (Germany) and expressed as a ratio between albumin and creatinine (ACR). BDNF median split x Gender interaction effects for structural ED justified stratification of BDNF into low and high (≤ / > 1.37 ng/ml) gender groups. Results and Conclusion - On average, male participants were overweight (BMI 25-30kg/m2) and abused more alcohol.21 African men revealed a vulnerable cardiometabolic profile with values exceeding cut–points (European Society of Hypertension). These men demonstrated increased acute and chronic glucose (HbA1c) levels indicating a pre-diabetic state; as well as a disturbed lipid profile with lower HdL and increased triglycerides. Overall BDNF levels were lower than reference ranges (6.97 – 42.6 ng/ml). The men revealed mean lower BDNF levels, ambulatory BP values exceeding guideline cut-points (ambulatory SBP > 130mmHg; DBP > 80mmHg) as well as a hypertensive state compared to their female counterparts. Pertaining to structural endothelial dysfunction, the mean ACR value in men exceeded normal laboratory values (< 3.5mg/mmol). The African women displayed an obese state with low grade inflammation (CRP, 12.27 ± 11.67mg/l). A single two-way ANCOVA interaction on main effects (BDNF median split x Gender) demonstrated significant interaction for CIMTf [F (1,164); 3.99, p=0.05] and cholesterol [F (1,164); 4.12, p=0.05]. Therefore, a median split approach was followed which stratified gender groups into lower (≤ 1.37 ng/ml) and higher BDNF levels (>1.37 ng/ml). The low BDNF men revealed higher cholesterol than the high BDNF group, independent of BMI and age. Only the low BDNF women indicated significantly higher values for structural vascular markers (p< 0.05) than the high BDNF female group. In conclusion, we accept our hypothesis, as hypertrophic remodelling of the carotid artery was associated with lower BDNF levels. This may imply attenuated or possibly down-regulated BDNF levels acting as a compensatory mechanism for the mean higher BP levels. In women, metabolic risk and hypertrophic remodelling were evident within higher circulating levels of BDNF, underpinning different underlying mechanisms for impaired neurotrophin health in men and women. Novel findings of BDNF revealed the impact of central neural regulation on the circulatory system, which may contribute to cardiometabolic risk in Africans. / MSc (Physiology), North-West University, Potchefstroom Campus, 2014

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