Global ETD Search

1051	Structure learning of Bayesian networks via data perturbation / Aprendizagem estrutural de Redes Bayesianas via perturbação de dados Tadeu Junior Gross 29 November 2018 (has links) Structure learning of Bayesian Networks (BNs) is an NP-hard problem, and the use of sub-optimal strategies is essential in domains involving many variables. One of them is to generate multiple approximate structures and then to reduce the ensemble to a representative structure. It is possible to use the occurrence frequency (on the structures ensemble) as the criteria for accepting a dominant directed edge between two nodes and thus obtaining the single structure. In this doctoral research, it was made an analogy with an adapted one-dimensional random-walk for analytically deducing an appropriate decision threshold to such occurrence frequency. The obtained closed-form expression has been validated across benchmark datasets applying the Matthews Correlation Coefficient as the performance metric. In the experiments using a recent medical dataset, the BN resulting from the analytical cutoff-frequency captured the expected associations among nodes and also achieved better prediction performance than the BNs learned with neighbours thresholds to the computed. In literature, the feature accounted along of the perturbed structures has been the edges and not the directed edges (arcs) as in this thesis. That modified strategy still was applied to an elderly dataset to identify potential relationships between variables of medical interest but using an increased threshold instead of the predict by the proposed formula - such prudence is due to the possible social implications of the finding. The motivation behind such an application is that in spite of the proportion of elderly individuals in the population has increased substantially in the last few decades, the risk factors that should be managed in advance to ensure a natural process of mental decline due to ageing remain unknown. In the learned structural model, it was graphically investigated the probabilistic dependence mechanism between two variables of medical interest: the suspected risk factor known as Metabolic Syndrome and the indicator of mental decline referred to as Cognitive Impairment. In this investigation, the concept known in the context of BNs as D-separation has been employed. Results of the carried out study revealed that the dependence between Metabolic Syndrome and Cognitive Variables indeed exists and depends on both Body Mass Index and age. / O aprendizado da estrutura de uma Rede Bayesiana (BN) é um problema NP-difícil, e o uso de estratégias sub-ótimas é essencial em domínios que envolvem muitas variáveis. Uma delas consiste em gerar várias estruturas aproximadas e depois reduzir o conjunto a uma estrutura representativa. É possível usar a frequência de ocorrência (no conjunto de estruturas) como critério para aceitar um arco dominante entre dois nós e assim obter essa estrutura única. Nesta pesquisa de doutorado, foi feita uma analogia com um passeio aleatório unidimensional adaptado para deduzir analiticamente um limiar de decisão apropriado para essa frequência de ocorrência. A expressão de forma fechada obtida foi validada usando bases de dados de referência e aplicando o Coeficiente de Correlação de Matthews como métrica de desempenho. Nos experimentos utilizando dados médicos recentes, a BN resultante da frequência de corte analítica capturou as associações esperadas entre os nós e também obteve melhor desempenho de predição do que as BNs aprendidas com limiares vizinhos ao calculado. Na literatura, a característica contabilizada ao longo das estruturas perturbadas tem sido as arestas e não as arestas direcionadas (arcos) como nesta tese. Essa estratégia modificada ainda foi aplicada a um conjunto de dados de idosos para identificar potenciais relações entre variáveis de interesse médico, mas usando um limiar aumentado em vez do previsto pela fórmula proposta - essa cautela deve-se às possíveis implicações sociais do achado. A motivação por trás dessa aplicação é que, apesar da proporção de idosos na população ter aumentado substancialmente nas últimas décadas, os fatores de risco que devem ser controlados com antecedência para garantir um processo natural de declínio mental devido ao envelhecimento permanecem desconhecidos. No modelo estrutural aprendido, investigou-se graficamente o mecanismo de dependência probabilística entre duas variáveis de interesse médico: o fator de risco suspeito conhecido como Síndrome Metabólica e o indicador de declínio mental denominado Comprometimento Cognitivo. Nessa investigação, empregou-se o conceito conhecido no contexto de BNs como D-separação. Esse estudo revelou que a dependência entre Síndrome Metabólica e Variáveis Cognitivas de fato existe e depende tanto do Índice de Massa Corporal quanto da idade. Aprendizado de estruturas robustas D-separação Descoberta de associações Envelhecimento da população Estabilidade de arcos Fatores de risco Grafo acíclico dirigido limiar analítico Média de modelos Perturbação de dados via bootstrap Rede Bayesiana Síndrome metabólica Transtorno cognitivo Analytical threshold Associations discovery Bayesian network Cognitive impairment D-separation Data perturbation via bootstrap replicas Directed acyclic graph Learning of robust structures Metabolic syndrome Model averaging Population ageing Risk factors Stability of arcs
1052	Exame médico periódico e risco cardiovascular em trabalhadores de uma grande empresa do Rio de Janeiro / Periodic medical examinations and cardiovascular risk in workers of a large company in Rio de Janeiro Bruno, Ana Cecilia Rocha January 2009 (has links) Made available in DSpace on 2011-05-04T12:36:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2009 / Neste estudo, foi analisado o risco cardiovascular de trabalhadores administrativos de uma grande empresa do Rio de Janeiro. Para tanto, a Síndrome Metabólica foi considerada como marcador, por encerrar um conjunto de alterações associadas a um elevado risco de doença cardiovascular e/ou diabetes, tais como obesidade abdominal, resistência insulínica, dislipidemia e hipertensão arterial. Os critérios para Síndrome Metabólica da Organização Mundial de Saúde, do Programa Nacional de Educação para o Colesterol-Terceiro Painel para Tratamento do Adulto e da Federação Internacional de Diabetes foram utilizados para diagnóstico, assim como o algoritmo de Framingham foi calculado. Dados do exame médico periódico foram reunidos, no período compreendido entre janeiro de 2003 até dezembro de 2007. Dos 2.052 exames realizados em 2003, 1.260 foram considerados para análise por estarem completos. Um grupo de 123 trabalhadores foi diagnosticado pelo critério da Federação Internacional de Diabetes e acompanhado durante cinco anos. Estabeleceu-se a relação entre a síndrome e as diversas ocupações, bem como com o absenteísmo. A prevalênciade 9,7 por cento foi abaixo da encontrada na literatura. Não foram observadas diferenças entre os grupos ocupacionais e, quanto ao absenteísmo, as faltas por problemas do aparelho circulatório foram a segunda causa mais importante. Verificou-se a baixa participação dos trabalhadores nos programas de saúde oferecidos. Os trabalhadores que realizaram exame médico periódico em 2007 foram diagnosticados pelos três critérios. A prevalência observada de 3,8 por cento com base no critério da Organização Mundial de Saúde; 16,6 por cento no Programa Nacional de Educação para o Colesterol-Terceiro Painel para Tratamento do Adulto e 16,3 por cento na Federação Internacional de Diabetes, novamente, foi abaixo da encontrada na literatura. O algoritmo de Framingham foi calculado e ao considerar a Síndrome Metabólica como fator agravante, quintuplicou-se a parcela de trabalhadores em alto risco para doenças cardiovasculares. Esse grupo necessita abordagem especial para tratamento médico e modificação do estilo de vida, a fim de reduzir o risco de incapacidade ou morte prematura. / In this dissertation the cardiovascular risk among office workers from a large company in Rio de Janeiro was studied. So, the Metabolic Syndrome was considered as a marker because it is associated with a clustering of components that increase the risk of cardiovascular disease and/or diabetes, like abdominal obesity, insulin resistance, dyslipidemia and elevated blood pressure. Among the several Metabolic Syndrome criteria the following three were used: World Health Organization, National Cholesterol Education Program - Third Adult Treatment Panel, and International Diabetes Federation. Also the Framingham Risk Score was calculated for this population and combined to the Metabolic Syndrome in order to improve the overall cardiovascular risk marker. Data were collected from the periodic medical examination between January 2003 and December 2007. From 2.052 exams realized in 2003, 1.260 were considered. A group of 123 workers was diagnosed with Metabolic Syndrome using the International Diabetes Federation criteria and followed during five years. The prevalence found of 9,7% was lower than the one reported in the literature. The Metabolic Syndrome prevalence was uniformly distributed between the different occupational groups in the company. Circulatory disorders were the second cause for lost workdays. Poor participation in the health programs available was observed. The workers who were submitted to the periodic medical examination in 2007 were diagnosed using the three criteria. The prevalence found were the following: World Health Organization - 3,8%; National Cholesterol Education Program- Third Adult Treatment Panel - 16,6%; and International Diabetes Federation - 16,3%. All the three were lower than the one reported in the literature. When the Metabolic Syndrome was added to the Framingham Risk Score as a grievance factor, a 5-fold increase in workers with high risk of cardiovascular disease was observed. This group is in need of a special approach for medical treatment and lifestyle change, in order to reduce disability and premature death. Risco Cardiovascular Síndrome Metabólica Circunferência Abdominal Exame Médico Periódico Trabalhadores Fatores de Risco Obesidade Síndrome X Metabólica Circunferência Abdominal Cardivascular Risk Metabolic Syndrome Waist Circumference Periodic Medical Examination. Trabalhadores -Fatores de Risco Obesidade/prevençäo & controle Circunferência Abdominal Serviços Preventivos de Saúde Saúde do Trabalhador Brasil
1053	Food addiction : a cost-effective treatment proposal within a developing country context Kistenmacher, Ann 01 1900 (has links) This study explores the possible efficacy of a low carbohydrate and high fat nutritional intervention (LCHF) as a treatment possibility aiming to improve the ability of self-control and regulation in the context of carbohydrate-addiction. The study first outlines why increased simple carbohydrate consumption has been implicated as a risk-factor in numerous chronic conditions, and then explores the possibility that a reduction of such consumption could lower general medical expenditure in the healthcare sector of already overburdened institutions, especially in developing countries like South Africa. Since the neurobiological evidence for food addiction is compelling, this study investigates the impact of a low carbohydrate and high fat eating (LCHF) regimen by measuring the change in the severity of addictive behaviour in relation to a reduced carbohydrate consumption. Results indicate that a LCHF nutritional intervention lessened addictive behaviour after just 30 days, resulting in a statistically significant decrease in addiction symptoms from day 1 to day 30. The weight and BMI values of the participants recorded at the end of the study showed a reduction from those obtained during the pre- treatment stage, and the self-perceived ‘feeling in control’ also improved in all participants after the intervention. The introduction of a LCHF nutritional intervention presents a relatively cost-effective treatment and preventative measure to combat carbohydrate over-consumption and its numerous health complications, and it is therefore hoped that the positive findings of this study will foster further research, using larger samples, into this type of nutritional intervention against addictive eating behaviour. / Psychology / M.A. (Psychology) Low carbohydrate High fat nutritional intervention LCHF Addiction severity Carbohydrate over- consumption Chronic conditions Cost-effective treatment intervention Preventative treatment Yale Food Addiction Scale YFAS Diabetes Carbohydrate addiction Sugar Inflammation Banting Ketogenic Depression Addiction Feeling in control Psychology Obesity Overburdened healthcare Metabolic syndrome Stress Immune response Gut microbiome 362.196852600968 Obesity -- South Africa Obesity -- Developing countries Nutrition -- South Africa Nutrition -- Developing countries Nutrition counseling -- South Africa
1054	BIRTHWEIGHT AND SUSCEPTIBILITY TO CHRONIC DISEASE Issa Al Salmi Unknown Date (has links) The thesis examines the relationship of birthweight to risk factors and markers, such as proteinuria and glomerular filtration rate, for chronic disease in postnatal life. It made use of the Australian Diabetes, Obesity and Lifestyle Study (AusDiab). The AusDiab study is a cross sectional study where baseline data on 11,247 participants were collected in 1999-2000. Participants were recruited from a stratified sample of Australians aged ≥ 25 years, residing in 42 randomly selected urban and non-urban areas (Census Collector Districts) of the six states of Australia and the Northern Territory. The AusDiab study collected an enormous amount of clinical and laboratory data. During the 2004-05 follow-up AusDiab survey, questions about birthweight were included. Participants were asked to state their birthweight, the likely accuracy of the stated birthweight and the source of their stated birthweight. Four hundred and twelve chronic kidney disease (CKD) patients were approached, and 339 agreed to participate in the study. The patients completed the same questionnaire. Medical records were reviewed to check the diagnoses, causes of kidney trouble and SCr levels. Two control subjects, matched for gender and age, were selected for each CKD patient from participants in the AusDiab study who reported their birthweight. Among 7,157 AusDiab participants who responded to the questionnaire, 4,502 reported their birthweights, with a mean (standard deviation) of 3.4 (0.7) kg. The benefit and disadvantages of these data are discussed in chapter three. The data were analysed for the relationship between birthweight and adult body size and composition, disorders of glucose regulation, blood pressure, lipid abnormalities, cardiovascular diseases and glomerular filtration rate. Low birthweight was associated with smaller body build and lower lean mass and total body water in both females and males. In addition low birthweight was associated with central obesity and higher body fat percentage in females, even after taking into account current physical activity and socioeconomic status. Fasting plasma glucose, post load glucose and glycosylated haemoglobin were strongly and inversely correlated with birthweight. In those with low birthweight (< 2.5 kg), the risks for having impaired fasting glucose, impaired glucose tolerance, diabetes and all abnormalities combined were increased by 1.75, 2.22, 2.76 and 2.28 for females and by 1.40, 1.32, 1.98 and 1.49 for males compared to those with normal birthweight (≥ 2.5 kg), respectively. Low birthweight individuals were at higher risk for having high blood pressure ≥ 140/90 mmHg and ≥ 130/85 mmHg compared to those with normal birthweight. People with low birthweight showed a trend towards increased risk for high cholesterol (≥ 5.5 mmol/l) compared to those of normal birthweight. Females with low birthweight had increased risk for high low density lipoprotein cholesterol (≥ 3.5 mmol/l) and triglyceride levels (≥ 1.7 mmol/l) when compared to those with normal birthweight. Males with low birthweight exhibited increased risk for low levels of high density lipoprotein cholesterol (<0.9 mmol/l) than those with normal birthweight. Females with low birthweight were at least 1.39, 1.40, 2.30 and 1.47 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases respectively, compared to those ≥ 2.5 kg. Similarly, males with low birthweight were 1.76, 1.48, 3.34 and 1.70 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases compared to those ≥ 2.5 kg, respectively. The estimated glomerular filtration rate was strongly and positively associated with birthweight, with a predicted increase of 2.6 ml/min (CI 2.1, 3.2) and 3.8 (3.0, 4.5) for each kg of birthweight for females and males, respectively. The odd ratio (95% confidence interval) for low glomerular filtration rate (<61.0 ml/min for female and < 87.4 male) in people of low birthweight compared with those of normal birthweight was 2.04 (1.45, 2.88) for female and 3.4 (2.11, 5.36) for male. One hundred and eighty-nineCKD patients reported their birthweight; 106 were male. Their age was 60.3(15) years. Their birthweight was 3.27 (0.62) kg, vs 3.46 (0.6) kg for their AusDiab controls, p<0.001 and the proportions with birthweight<2.5 kg were 12.17% and 4.44%, p<0.001. Among CKD patients, 22.8%, 21.7%, 18% and 37.6% were in CKD stages 2, 3, 4 and 5 respectively. Birthweights by CKD stage and their AusDiab controls were as follows: 3.38 (0.52) vs 3.49 (0.52), p=0.251 for CKD2; 3.28 (0.54) vs 3.44 (0.54), p=0.121 for CKD3; 3.19 (0.72) vs 3.43 (0.56), p= 0.112 for CKD4 and 3.09 (0.65) vs 3.47 (0.67), p<0.001 for CKD5. The results demonstrate that in an affluent Western country with a good adult health profile, low birthweight people were predisposed to higher rates of glycaemic dysregulation, high blood pressure, dyslipidaemia, cardiovascular diseases and lower glomerular filtration rate in adult life. In all instances it would be prudent to adopt policies of intensified whole of life surveillance of lower birthweight people, anticipating this risk. The general public awareness of the effect of low birthweight on development of chronic diseases in later life is of vital importance. The general public, in addition to the awareness of people in medical practice of the role of low birthweight, will lead to a better management of this group of our population that is increasingly surviving into adulthood. birth weight birthweight birth weight and renal volume BIRTH WEIGHT QUESTIONNAIRE chronic disease Barker Hypothesis Foetal development DOHaD gestational age Anthropometric Characteristics body composition Height weight body mass index Waist Circumference hip circumference Waist-hip Ratio obesity Central Obesity Fatness Lean Body Mass Lean Mass Fat Mass body fat mass Body Fat Percentage body fatness Body Surface Area diabetes Fasting Glucose fasting insulin level glucose tolerance Impaired Fasting Glucose Impaired Glucose Tolerance Glycosylated Hemoglobin HbA1c IFG glucose control glycaemic control Metabolic Syndrome Syndrome X blood pressure Systolic Blood-pressure Diastolic Blood-pressure Systolic Hypertension high blood pressure Hypertension Dyslipidaemia Dyslipidemia Total Cholesterol Triglyceride Low Density Lipoprotein Cholesterol Ldl Cholesterol High Density Lipoprotein Hdl Cholesterol Fibrinogen angina Angina-pectoris Stroke coronary artery disease cardiovascular disease Framingham Framingham Heart Study Framingham Score coronary heart disease Glomerular Filtration glomerular filtration rate Glomerular Hyperfiltration Glomerular Injury Glomerular Number Nephrogenesis Nephron Endowment Nephron Number NKF-K/DQQI Classification Chronic Kidney Disease (ckd) Chronic Kidney Failure Kidney Failure CKD STAGES end-stage renal disease (ESRD) end-stage renal failure Cockcroft-gault MDRD formula Serum Creatinine Urinary Creatinine albuminuria Albuminuria:creatinine Ratio Kidney Development Kidney dysfunction low birth weight low birth weight Pre-term Birth AusDiab Study case control longitudinal observational study
1055	BIRTHWEIGHT AND SUSCEPTIBILITY TO CHRONIC DISEASE Issa Al Salmi Unknown Date (has links) The thesis examines the relationship of birthweight to risk factors and markers, such as proteinuria and glomerular filtration rate, for chronic disease in postnatal life. It made use of the Australian Diabetes, Obesity and Lifestyle Study (AusDiab). The AusDiab study is a cross sectional study where baseline data on 11,247 participants were collected in 1999-2000. Participants were recruited from a stratified sample of Australians aged ≥ 25 years, residing in 42 randomly selected urban and non-urban areas (Census Collector Districts) of the six states of Australia and the Northern Territory. The AusDiab study collected an enormous amount of clinical and laboratory data. During the 2004-05 follow-up AusDiab survey, questions about birthweight were included. Participants were asked to state their birthweight, the likely accuracy of the stated birthweight and the source of their stated birthweight. Four hundred and twelve chronic kidney disease (CKD) patients were approached, and 339 agreed to participate in the study. The patients completed the same questionnaire. Medical records were reviewed to check the diagnoses, causes of kidney trouble and SCr levels. Two control subjects, matched for gender and age, were selected for each CKD patient from participants in the AusDiab study who reported their birthweight. Among 7,157 AusDiab participants who responded to the questionnaire, 4,502 reported their birthweights, with a mean (standard deviation) of 3.4 (0.7) kg. The benefit and disadvantages of these data are discussed in chapter three. The data were analysed for the relationship between birthweight and adult body size and composition, disorders of glucose regulation, blood pressure, lipid abnormalities, cardiovascular diseases and glomerular filtration rate. Low birthweight was associated with smaller body build and lower lean mass and total body water in both females and males. In addition low birthweight was associated with central obesity and higher body fat percentage in females, even after taking into account current physical activity and socioeconomic status. Fasting plasma glucose, post load glucose and glycosylated haemoglobin were strongly and inversely correlated with birthweight. In those with low birthweight (< 2.5 kg), the risks for having impaired fasting glucose, impaired glucose tolerance, diabetes and all abnormalities combined were increased by 1.75, 2.22, 2.76 and 2.28 for females and by 1.40, 1.32, 1.98 and 1.49 for males compared to those with normal birthweight (≥ 2.5 kg), respectively. Low birthweight individuals were at higher risk for having high blood pressure ≥ 140/90 mmHg and ≥ 130/85 mmHg compared to those with normal birthweight. People with low birthweight showed a trend towards increased risk for high cholesterol (≥ 5.5 mmol/l) compared to those of normal birthweight. Females with low birthweight had increased risk for high low density lipoprotein cholesterol (≥ 3.5 mmol/l) and triglyceride levels (≥ 1.7 mmol/l) when compared to those with normal birthweight. Males with low birthweight exhibited increased risk for low levels of high density lipoprotein cholesterol (<0.9 mmol/l) than those with normal birthweight. Females with low birthweight were at least 1.39, 1.40, 2.30 and 1.47 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases respectively, compared to those ≥ 2.5 kg. Similarly, males with low birthweight were 1.76, 1.48, 3.34 and 1.70 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases compared to those ≥ 2.5 kg, respectively. The estimated glomerular filtration rate was strongly and positively associated with birthweight, with a predicted increase of 2.6 ml/min (CI 2.1, 3.2) and 3.8 (3.0, 4.5) for each kg of birthweight for females and males, respectively. The odd ratio (95% confidence interval) for low glomerular filtration rate (<61.0 ml/min for female and < 87.4 male) in people of low birthweight compared with those of normal birthweight was 2.04 (1.45, 2.88) for female and 3.4 (2.11, 5.36) for male. One hundred and eighty-nineCKD patients reported their birthweight; 106 were male. Their age was 60.3(15) years. Their birthweight was 3.27 (0.62) kg, vs 3.46 (0.6) kg for their AusDiab controls, p<0.001 and the proportions with birthweight<2.5 kg were 12.17% and 4.44%, p<0.001. Among CKD patients, 22.8%, 21.7%, 18% and 37.6% were in CKD stages 2, 3, 4 and 5 respectively. Birthweights by CKD stage and their AusDiab controls were as follows: 3.38 (0.52) vs 3.49 (0.52), p=0.251 for CKD2; 3.28 (0.54) vs 3.44 (0.54), p=0.121 for CKD3; 3.19 (0.72) vs 3.43 (0.56), p= 0.112 for CKD4 and 3.09 (0.65) vs 3.47 (0.67), p<0.001 for CKD5. The results demonstrate that in an affluent Western country with a good adult health profile, low birthweight people were predisposed to higher rates of glycaemic dysregulation, high blood pressure, dyslipidaemia, cardiovascular diseases and lower glomerular filtration rate in adult life. In all instances it would be prudent to adopt policies of intensified whole of life surveillance of lower birthweight people, anticipating this risk. The general public awareness of the effect of low birthweight on development of chronic diseases in later life is of vital importance. The general public, in addition to the awareness of people in medical practice of the role of low birthweight, will lead to a better management of this group of our population that is increasingly surviving into adulthood. birth weight birthweight birth weight and renal volume BIRTH WEIGHT QUESTIONNAIRE chronic disease Barker Hypothesis Foetal development DOHaD gestational age Anthropometric Characteristics body composition Height weight body mass index Waist Circumference hip circumference Waist-hip Ratio obesity Central Obesity Fatness Lean Body Mass Lean Mass Fat Mass body fat mass Body Fat Percentage body fatness Body Surface Area diabetes Fasting Glucose fasting insulin level glucose tolerance Impaired Fasting Glucose Impaired Glucose Tolerance Glycosylated Hemoglobin HbA1c IFG glucose control glycaemic control Metabolic Syndrome Syndrome X blood pressure Systolic Blood-pressure Diastolic Blood-pressure Systolic Hypertension high blood pressure Hypertension Dyslipidaemia Dyslipidemia Total Cholesterol Triglyceride Low Density Lipoprotein Cholesterol Ldl Cholesterol High Density Lipoprotein Hdl Cholesterol Fibrinogen angina Angina-pectoris Stroke coronary artery disease cardiovascular disease Framingham Framingham Heart Study Framingham Score coronary heart disease Glomerular Filtration glomerular filtration rate Glomerular Hyperfiltration Glomerular Injury Glomerular Number Nephrogenesis Nephron Endowment Nephron Number NKF-K/DQQI Classification Chronic Kidney Disease (ckd) Chronic Kidney Failure Kidney Failure CKD STAGES end-stage renal disease (ESRD) end-stage renal failure Cockcroft-gault MDRD formula Serum Creatinine Urinary Creatinine albuminuria Albuminuria:creatinine Ratio Kidney Development Kidney dysfunction low birth weight low birth weight Pre-term Birth AusDiab Study case control longitudinal observational study
1056	BIRTHWEIGHT AND SUSCEPTIBILITY TO CHRONIC DISEASE Issa Al Salmi Unknown Date (has links) The thesis examines the relationship of birthweight to risk factors and markers, such as proteinuria and glomerular filtration rate, for chronic disease in postnatal life. It made use of the Australian Diabetes, Obesity and Lifestyle Study (AusDiab). The AusDiab study is a cross sectional study where baseline data on 11,247 participants were collected in 1999-2000. Participants were recruited from a stratified sample of Australians aged ≥ 25 years, residing in 42 randomly selected urban and non-urban areas (Census Collector Districts) of the six states of Australia and the Northern Territory. The AusDiab study collected an enormous amount of clinical and laboratory data. During the 2004-05 follow-up AusDiab survey, questions about birthweight were included. Participants were asked to state their birthweight, the likely accuracy of the stated birthweight and the source of their stated birthweight. Four hundred and twelve chronic kidney disease (CKD) patients were approached, and 339 agreed to participate in the study. The patients completed the same questionnaire. Medical records were reviewed to check the diagnoses, causes of kidney trouble and SCr levels. Two control subjects, matched for gender and age, were selected for each CKD patient from participants in the AusDiab study who reported their birthweight. Among 7,157 AusDiab participants who responded to the questionnaire, 4,502 reported their birthweights, with a mean (standard deviation) of 3.4 (0.7) kg. The benefit and disadvantages of these data are discussed in chapter three. The data were analysed for the relationship between birthweight and adult body size and composition, disorders of glucose regulation, blood pressure, lipid abnormalities, cardiovascular diseases and glomerular filtration rate. Low birthweight was associated with smaller body build and lower lean mass and total body water in both females and males. In addition low birthweight was associated with central obesity and higher body fat percentage in females, even after taking into account current physical activity and socioeconomic status. Fasting plasma glucose, post load glucose and glycosylated haemoglobin were strongly and inversely correlated with birthweight. In those with low birthweight (< 2.5 kg), the risks for having impaired fasting glucose, impaired glucose tolerance, diabetes and all abnormalities combined were increased by 1.75, 2.22, 2.76 and 2.28 for females and by 1.40, 1.32, 1.98 and 1.49 for males compared to those with normal birthweight (≥ 2.5 kg), respectively. Low birthweight individuals were at higher risk for having high blood pressure ≥ 140/90 mmHg and ≥ 130/85 mmHg compared to those with normal birthweight. People with low birthweight showed a trend towards increased risk for high cholesterol (≥ 5.5 mmol/l) compared to those of normal birthweight. Females with low birthweight had increased risk for high low density lipoprotein cholesterol (≥ 3.5 mmol/l) and triglyceride levels (≥ 1.7 mmol/l) when compared to those with normal birthweight. Males with low birthweight exhibited increased risk for low levels of high density lipoprotein cholesterol (<0.9 mmol/l) than those with normal birthweight. Females with low birthweight were at least 1.39, 1.40, 2.30 and 1.47 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases respectively, compared to those ≥ 2.5 kg. Similarly, males with low birthweight were 1.76, 1.48, 3.34 and 1.70 times more likely to have angina, coronary artery disease, stroke and overall cardiovascular diseases compared to those ≥ 2.5 kg, respectively. The estimated glomerular filtration rate was strongly and positively associated with birthweight, with a predicted increase of 2.6 ml/min (CI 2.1, 3.2) and 3.8 (3.0, 4.5) for each kg of birthweight for females and males, respectively. The odd ratio (95% confidence interval) for low glomerular filtration rate (<61.0 ml/min for female and < 87.4 male) in people of low birthweight compared with those of normal birthweight was 2.04 (1.45, 2.88) for female and 3.4 (2.11, 5.36) for male. One hundred and eighty-nineCKD patients reported their birthweight; 106 were male. Their age was 60.3(15) years. Their birthweight was 3.27 (0.62) kg, vs 3.46 (0.6) kg for their AusDiab controls, p<0.001 and the proportions with birthweight<2.5 kg were 12.17% and 4.44%, p<0.001. Among CKD patients, 22.8%, 21.7%, 18% and 37.6% were in CKD stages 2, 3, 4 and 5 respectively. Birthweights by CKD stage and their AusDiab controls were as follows: 3.38 (0.52) vs 3.49 (0.52), p=0.251 for CKD2; 3.28 (0.54) vs 3.44 (0.54), p=0.121 for CKD3; 3.19 (0.72) vs 3.43 (0.56), p= 0.112 for CKD4 and 3.09 (0.65) vs 3.47 (0.67), p<0.001 for CKD5. The results demonstrate that in an affluent Western country with a good adult health profile, low birthweight people were predisposed to higher rates of glycaemic dysregulation, high blood pressure, dyslipidaemia, cardiovascular diseases and lower glomerular filtration rate in adult life. In all instances it would be prudent to adopt policies of intensified whole of life surveillance of lower birthweight people, anticipating this risk. The general public awareness of the effect of low birthweight on development of chronic diseases in later life is of vital importance. The general public, in addition to the awareness of people in medical practice of the role of low birthweight, will lead to a better management of this group of our population that is increasingly surviving into adulthood. birth weight birthweight birth weight and renal volume BIRTH WEIGHT QUESTIONNAIRE chronic disease Barker Hypothesis Foetal development DOHaD gestational age Anthropometric Characteristics body composition Height weight body mass index Waist Circumference hip circumference Waist-hip Ratio obesity Central Obesity Fatness Lean Body Mass Lean Mass Fat Mass body fat mass Body Fat Percentage body fatness Body Surface Area diabetes Fasting Glucose fasting insulin level glucose tolerance Impaired Fasting Glucose Impaired Glucose Tolerance Glycosylated Hemoglobin HbA1c IFG glucose control glycaemic control Metabolic Syndrome Syndrome X blood pressure Systolic Blood-pressure Diastolic Blood-pressure Systolic Hypertension high blood pressure Hypertension Dyslipidaemia Dyslipidemia Total Cholesterol Triglyceride Low Density Lipoprotein Cholesterol Ldl Cholesterol High Density Lipoprotein Hdl Cholesterol Fibrinogen angina Angina-pectoris Stroke coronary artery disease cardiovascular disease Framingham Framingham Heart Study Framingham Score coronary heart disease Glomerular Filtration glomerular filtration rate Glomerular Hyperfiltration Glomerular Injury Glomerular Number Nephrogenesis Nephron Endowment Nephron Number NKF-K/DQQI Classification Chronic Kidney Disease (ckd) Chronic Kidney Failure Kidney Failure CKD STAGES end-stage renal disease (ESRD) end-stage renal failure Cockcroft-gault MDRD formula Serum Creatinine Urinary Creatinine albuminuria Albuminuria:creatinine Ratio Kidney Development Kidney dysfunction low birth weight low birth weight Pre-term Birth AusDiab Study case control longitudinal observational study

Page generated in 0.0709 seconds