Uma ativação do trato olivococlear medial reduz a amplitude das emissões otoacústicas de forma lateralizada, com um predomínio à direita. Pessoas com zumbido teriam uma disfunção do reflexo eferente, mas esses resultados não foram comprovados em todas as pesquisas. Curiosamente, estas pesquisas não valorizam a lateralidade eferente. Comparamos a supressão na orelha direita de pessoas com e sem zumbido e a lateralidade do sistema eferente pela análise da supressão à direita e à esquerda no grupo sem zumbido. Concluímos que há relação entre zumbido e não supressão e que à direita, a supressão é maior / An activation of the medial olivocochlear tract reduces the amplitude of otoacoustic emissions with predominance of the right side. Subjects with tinnitus would have an abnormality of the suppressing reflex, but such results have not been confirmed yet in any study. Curiously, such studies did not value the functional laterality. We compared right ear suppression of people with and without tinnitus, and the suppression on the right and on the left in the group without tinnitus. We concluded that there was a relation between tinnitus and absent suppression of otoacoustic emissions and right ear suppression was more marked.

O Transtorno obsessivo-compulsivo (TOC) é um transtorno psiquiátrico comum e heterogêneo caracterizado por obsessões (pensamentos, imagens ou impulsos intrusivos e recorrentes) e compulsões (comportamentos ou atos mentais repetitivos realizados para aliviar as obsessões). O TOC tem uma prevalência de 2 a 3% na população geral e apresenta distribuição aproximadamente igual entre os sexos, porém os homens tendem a apresentar os sintomas obsessivo-compulsivos mais precocemente quando comparado com as mulheres. Os estudos de genética epidemiológica têm demonstrado que o fator genético é um importante componente na etiologia do TOC. O principal objetivo desta dissertação foi investigar a influência de alguns genes candidatos na susceptibilidade para o TOC (estudo de genes candidatos) e também qual a influência destes mesmos genes na resposta terapêutica à clomipramina (estudo de farmacogenética). Realizamos o estudo de genes candidatos num total de 215 pacientes e 872 controles. Os loci investigados foram: SLC6A4, HTR1B, HTR2A, SLC6A3, COMT e SLC6A2. Os mesmos polimorfismos foram investigados em uma sub-amostra de 41 pacientes tratados com clomipramina e analisados de acordo com a resposta terapêutica. Foram classificados como respondedores ao tratamento, os pacientes que tiveram uma redução de 40% ou mais na escala YBOCS. Assim, 27 pacientes foram considerados respondedores e 14 nãorespondedores. Diferenças genotípicas e alélicas foram observadas em alguns resultados nos pacientes e controles. Entretanto, nenhuma associação foi observada nas análises para resposta à clomipramina. Os resultados sugerem que alguns polimorfismos estudados podem estar relacionados ao aumento do risco para o TOC, porém, nenhum polimorfismo foi associado à resposta terapêutica à clomipramina. / Obsessive-compulsive disorder (OCD) is a common and heterogeneous psychiatric disorder characterized by obsessions (intrusive and recurrent thoughts, images or impulses) and compulsions (repetitive behaviors or mental acts performed to relive obsessions). OCD prevalence range from 2 to 3% in general population and has approximately equal sex distributions, however men tend to have an earlier age at onset of obsessive-compulsive symptoms comparing to women. Epidemiologic studies have demonstrated that genetic factor is an important component in the etiology of OCD. The aim of this study was to investigate participation of some candidate genes in the susceptibility to OCD and also their effects on clomipramine treatment. We performed a candidate gene study in a total of 215 OCD patients and 865 controls. The loci investigated were: SLC6A4, HTR1B, HTR2A, SLC6A3, COMT and SLC6A2. The same polymorphisms were investigated in a sub-sample of 41 patients treated with clomipramine, and analyzed according to therapeutic response. There were considered good responders to the drug those patients who presented a reduction of 40% or more in Y-BOCS scale. According to this, 27 patients were good responders and 14 poor responders. Genotypic and allelic differences were observed in some results for patients and controls. However, no association was observed in the analyses for clomipramine response. Our results suggest that some polymorphisms investigated may be related to the increase of risk to develop OCD, but they are not associated to therapeutic response to clomipramine.

Submitted by Verena Bastos (verena@uefs.br) on 2015-07-28T14:42:09Z No. of bitstreams: 1 DEFESA JARIELLE_CORRIGIDO.pdf: 1378755 bytes, checksum: 49f317cd13e71302fe9ccbf2c0e8d745 (MD5) / Made available in DSpace on 2015-07-28T14:42:09Z (GMT). No. of bitstreams: 1 DEFESA JARIELLE_CORRIGIDO.pdf: 1378755 bytes, checksum: 49f317cd13e71302fe9ccbf2c0e8d745 (MD5) Previous issue date: 2014-03-14 / INTRODUCTION: Oral cancer is a public health problem in Brazil and around the world. Its etiology is multifactorial, tobacco and alcohol are the most important risk factors; in addition, solar radiation, HPV, diet and social conditions has been listed as risk factors for the development of this neoplasm. OBJECTIVE: This research aims to know the association between factors such as: age, sex, skin color, occupation, marital status, level of education, place of residence, use of tobacco, alcohol consumption and oral cancer in subjects attended in Reference Center for Oral Lesions, of the Brazil?s Northeast since 2002 to 2012. METHODOLOGY: This study is a case control study. The cases were formed by all population of subjects attended in this Center, with histopatologycal diagnose of oral squamous cell carcinoma, that it corresponds 127 individuals. The control group was consisted of 254 individuals from the same reference center where cases were recruited with other diseases, but without oral cancer or premalignant lesions. It considered two controls for each case. Cases and controls were adjusted by sex and age. After collecting the data it was performed univariate analysis, after the bivariate analysis (Chi Square test of Pearson) to determine the association between the dependent variable (oral cancer) and the independent variables; odds ratios (OR) and confidence interval of 95% were calculated. Finally, in the multivariate analysis was used hierarchical model with logistic regression to evaluate the interrelationships between the independent variables and oral cancer, considering the blocks of distal and proximal variables. RESULTS: The results showed that consuming more than 20 cigarettes per day [OR = 6.64; CI =2.07-21.32], high intake alcohol [OR= 3.25; CI =1.03-10.22] and the synergistic use of tobacco and alcohol [OR = 9.65; CI= 1.57-59.08] are the most important risk factors for oral cancer. CONCLUSION: The associated factors for oral cancer were smoking and drinking. Socio-demographic factors were not associated with oral cancer after adjustment for smoking and alcohol consumption. / INTRODU??O: O c?ncer de boca ? um problema de sa?de p?blica no Brasil e no mundo. Sua etiologia ? multifatorial, sendo o tabaco e o ?lcool os fatores de risco mais importantes; al?m destes, a radia??o solar, o HPV, a dieta e as condi??es sociais t?m sido elencados como fatores de risco para o desenvolvimento dessa neoplasia. OBJETIVO: Este estudo objetiva conhecer a associa??o entre fatores como: idade, sexo, cor da pele, ocupa??o, situa??o conjugal, n?vel de escolaridade, local de resid?ncia, tabagismo, etilismo e o c?ncer de boca em indiv?duos atendidos em um Centro de Refer?ncia de Les?es Bucais do Nordeste do Brasil de 2002 a 2012. METODOLOGIA: Esse ? um estudo de caso-controle. O grupo caso foi formado por toda a popula??o de indiv?duos com diagn?stico histopatol?gico de carcinoma de c?lulas escamosas de boca, que corresponde a 127 indiv?duos. O grupo controle foi composto por 254 indiv?duos do mesmo centro de refer?ncia em que os casos foram recrutados, com outras doen?as que n?o c?ncer de boca ou les?es potencialmente malignas. Considerou-se dois controles para cada caso. Casos e controles foram ajustados segundo sexo e idade. Ap?s a coleta dos dados, foram realizadas as an?lises univariada e bivariada (teste Qui Quadrado de Pearson) para verificar a associa??o entre a vari?vel dependente (c?ncer de boca) e as vari?veis independentes; foram calculadas a odds ratio (OR) e o intervalo de confian?a a 95%. Por fim, na an?lise multivariada, foi utilizado o modelo hierarquizado com regress?o log?stica para avaliar as inter-rela??es entre as vari?veis independentes e o c?ncer de boca, considerando-se os blocos de vari?veis distais e proximais. RESULTADOS: Os resultados mostraram que o consumo de mais de 20 cigarros por dia [OR= 6,64; IC= 2,07-21,32], a alta ingest?o de bebida alco?lica [OR= 3,25; IC= 1,03-10,22] e o consumo sin?rgico de tabaco e ?lcool [OR=9,65; IC= 1,57-59,08] s?o os fatores de risco mais importantes para o c?ncer de boca. CONCLUS?O: Os fatores associados para o c?ncer de boca foram tabagismo e etilismo. Fatores s?cio-demogr?ficos n?o apresentaram associa??o com o c?ncer de boca, ap?s ajuste para tabagismo e etilismo.

Introdução. Considerando-se a incidência e os reflexos na qualidade de vida, os tumores de cabeça e pescoço constituem-se em relevante problema de saúde pública. A medida de efeito dos principais fatores de risco, tabaco e álcool, no risco de acometimento de cânceres de cabeça e pescoço tem sido pouco relatada no Brasil. Objetivo. Verificar as variações de risco decorrentes do tabagismo e do consumo de bebidas alcoólicas no câncer de cabeça e pescoço nas regiões Sudeste, Sul e Centrooeste do Brasil. Sujeitos e Métodos. Estudo caso-controle de base hospitalar conduzido entre setembro de 1998 e maio de 2003, com base em 1.594 casos diagnosticados com carcinoma espinocelular de cabeça e pescoço, confirmados histologicamente, em hospitais das cidades de São Paulo e Rio de Janeiro (Sudeste), Porto Alegre e Pelotas (Sul), Goiânia (Centro-oeste), e 1.292 controles. Os pacientes foram entrevistados por meio de questionários com informações sobre características e hábitos, bem como dados clínicos e laboratoriais para o diagnóstico de câncer de cabeça e pescoço. A OR (odds ratio) e IC 95 por cento (intervalo com 95 por cento de confiança) para câncer de cabeça e pescoço associados ao tabaco e álcool foram estimados por regressão logística não condicional. O modelo foi ajustado por idade, sexo, escolaridade, consumo de frutas e legumes. Resultados. Na região Centro-oeste observaram-se riscos mais expressivos para tabagismo, ex-fumantes (OR 3,5; IC95 por cento 1,6-7,4) e fumantes (OR 13,6 IC95 por cento 6,4-28,6), com efeito dose-resposta para frequência e tempo de consumo na exposição cumulativa, de 1-9 maços-ano (OR 1,9; IC 95 por cento 0,8-4,4) à 40 maços-ano e mais (OR 8,6; IC95 por cento 4,2-17,5). No consumo de bebidas alcoólicas, observou-se riscos mais elevados para consumidores atuais na região Sul (OR 4,7 IC95 por cento 2,8-7,9); na exposição cumulativa o efeito dose-resposta para frequência de consumo foi nítido a partir da categoria 0-4,99g/ml/dia nas regiões Sudeste, Sul e Centro-oeste. Conclusões. As diferenças que puderam ser observadas no risco para tumores de cabeça e pescoço decorrentes do tabagismo e consumo de bebidas alcoólicas, sugerem diferenças no perfil de consumo nas regiões Sudeste, Sul e Centro-oeste, provavelmente, relacionados ao uso de tipos de preparo do tabaco e consumo de diferentes tipos de bebidas alcoólicas / Introduction. Considering the incidence and reflections on the quality of life, the head and neck tumors constitute an important public health problem. The extent of effect of the main risk factors, tobacco and alcohol, in risk of involvement of head and neck cancers has been rarely reported in Brazil. Objectives. Check the variations the risks caused by smoking and alcohol consumption in head and neck cancer in the Southeast, South and Midwest regions of Brazil. Subjects and Methods. A case-control hospitalbased, conducted between September 1998 and May 2003, based on 1.594 cases diagnosed with squamous cell carcinoma of the head and neck, histologically confirmed, in hospitals in the cities of São Paulo and Rio de Janeiro (Southeast), Porto Alegre and Pelotas (South), Goiania (Midwest), and 1.292 controls. Patients were interviewed using questionnaires with information about characteristics and habits, as well as clinical and laboratory data for the diagnosis of head and neck cancer. The odds ratio (OR) and IC95 per cent (confidence interval 95 per cent ) of head and neck cancer associated with tobacco and alcohol were estimated by unconditional logistic regression. The model was adjusted for age, sex, education, consumption of fruit and vegetables. Results. In the Midwest region we observed more significant risks for smoking, former smokers (OR 3,5; IC95 per cent 1,67,4) and smoking (OR 13,6; IC95 per cent 6,4-28,6), with doseresponse effect for frequency and time consumption in the cumulative exposure, from 1-9 pack-years (OR 1.9, IC95 per cent 0,84,4) to 40 pack-years and more (OR 8,6; IC95 per cent 4,2 17,5). In alcohol consumption was observed increased risks for current consumers in the South (OR 4,7; IC95 per cent 2,8 7,9); in the cumulative exposure dose-response effect for frequency of consumption was clear from the category 0-4,99 g/ml/day in the Southeast, South and Midwest regions. Conclusions. The differences in risk were observed for cancers of the head and neck caused by smoking and alcohol consumption suggest differences in the consumption profile in Southeast, South and Midwest regions, probably related to the use of types of tobacco and consumption of different types of alcoholic beverages

Le cancer du sein est le cancer le plus fréquent chez la femme dans le monde. Au Maroc, comme dans de nombreux pays en voie de développement, l'incidence du cancer du sein a considérablement augmenté ces dernières années. Le rôle des facteurs de risque reconnus et suspectés dans la survenue du cancer du sein est peu étudié au Maroc. L'objectif principal de cette thèse était de déterminer les principaux facteurs de risque du cancer du sein chez les femmes marocaines dans la région de Fès- Maroc. Méthodes : Ce travail porte sur les données de deux études cas-témoins réalisées dans la région de Fès- Maroc : l'étude "Fez Breast Cancer Study" (2014-2015) incluant 237 cas et 237 témoins appariés sur l'âge, et l'étude "BreCaFez Study " (2016-2017) incluant 300 cas et 300 témoins appariés sur l'âge et le milieu de résidence. Des informations détaillées sur les facteurs de risque du cancer du sein ont été recueillies au cours d'entretiens en face-à-face. Les odds ratios et leurs intervalles de confiance à 95% ont été estimés à partir de régressions logistiques, en ajustant sur les variables de confusion. Résultats : Nos résultats montrent que (1) l'âge précoce de la ménarche et la nulliparité étaient significativement associés à une augmentation de risque de cancer du sein, tandis que l'âge précoce à la première grossesse à terme est associé à une diminution de ce risque ; (2) un score de mode de vie sain élevé était associé significativement à une réduction du risque de cancer du sein chez les femmes de notre population ; (3) un excès d'adiposité abdominale et une forte évolution de trajectoire de la silhouette étaient associés à une augmentation de risque du cancer de sein chez les femmes en pré- et en postménopause. En revanche, une large silhouette à l'enfance (6–11 ans) était associée à une diminution significative de risque de cancer du sein chez les femmes en préménopause et à la limite de la signification statistique chez les femmes en postménopause ; (4) les femmes ayant travaillées dans certaines professions du secteur de l'agriculture, en particulier celles employées comme ouvrière agricole, avaient un risque élevé de cancer du sein, une augmentation significative de ce risque en fonction de la durée de l'emploi a été également observée. Conclusion : Ce travail suggère l'existence d'associations entre certains facteurs de risque et la survenue de cancer du sein chez les femmes de notre région. Les résultats de nos études peuvent orienter les mesures et les activités de prévention de cancer du sein dans notre pays. Par ailleurs, des études à plus grande échelle sont nécessaires pour confirmer et compléter nos résultats / Introduction Breast cancer is the most common cancer among women worldwide. In Morocco, as in many countries that are either developing or in epidemiological transition, breast cancer incidence rates have clearly risen. Numerous risk factors for female breast cancer have been identified in the literature, but their role in breast cancer among Moroccan women remains poorly documented. The purpose of this doctoral work was to investigate the association between several risk factors and breast cancer among Moroccan women in the Fez region, Morocco. Methods Our analyses were based on data from two case controls studies conducted in the Fez region, Morocco: "Fez Breast Cancer Study" (2014-2015) including 237 cases and 237 age-matched controls, and the "BreCaFez Study" (2016-2017) including 300 cases and 300 controls matched by age and area of residence. Detailed information on various risk factors of breast cancer were collected through face-to face interviews. Odds ratios and 95% confidence intervals, adjusted for potential confounders were estimated by using logistic regression models. Results Our findings suggest that (1) Early menarche and nulliparity were significantly associated with an increased risk of breast cancer among women of our population, whereas an early age at first full-term pregnancy was associated with a significantly decreased risk of breast cancer. (2) High healthy lifestyle index scores were associated with decreased risk of breast cancer in Moroccan women included in our study. (3) Central adiposity and body shape trajectory were positively associated with breast cancer risk in both pre- and post-menopausal women; whereas, a significant inverse association was observed between silhouette at young ages (6- 11 years) and BC risk for premenopausal women and a borderline significant inverse association for postmenopausal women. (4) Women employed in specific agricultural occupations, particularly those who worked as crop farm laborers, had an elevated risk of breast cancer compared to those who never worked in these occupations and the risk increased with duration of employment. Conclusion Our results showed the association between some risk factors and breast cancer among women in our region. It identified some susceptible groups at high risk of breast cancer. Preventive interventions and screening should focus on these groups as a priority. However, our findings should be confirmed in larger, multicenter studies

Dietary factors may affect development and progression of prostate cancer. Experimental and epidemiological studies have suggested an effect of phytoestrogens on prostate cancer. Lignans are the predominant phytoestrogen in a Western diet. The effects of a diet rich in phytoestrogens and in particular lignans, as compared to a control diet, were assessed in several prostate cancer models. In paper I, 70 athymic nude mice with transplanted subcutaneous LNCaP tumours, an androgen sensitive human prostate cancer cell line, were fed one out of six phytoestrogen rich diets or a control diet after tumour injection. The rye diet, with high lignan content, decreased tumour take and growth, decreased secretion of prostate specific antigen and increased apoptosis. Addition of fat to the rye diet decreased the beneficial effects. In paper II, transgenic mice designed to develop prostate cancer (TRAMP) were fed rye bran or a control diet from the age of four weeks. Rye bran decreased prostate epithelial cell volume by 20%, and increased cell apoptosis by 31% as compared to the control diet. In paper III, we examined the effects of 7-hydroxymatairesinol (HMR), a purified lignan, in nude mice with subcutaneous LNCaP tumours in two different concentrations as compared to a control diet. Mice on the HMR diets had a reduced tumour take rate, lower total tumour volume, increased proportion of non-growing tumours, and increased apoptosis as compared to the control diet. Paper IV was a three week intervention study exploring the effects of rye bran bread vs. a control diet in men with prostate cancer. The men in the rye group had increased levels of plasma enterolactone and in biopsies from the prostate after the intervention an increase in apoptosis was observed in comparison with biopsies obtained before the intervention. In paper V, we examined the association between plasma levels of enterolactone, and risk of prostate cancer in a nested case control study. In the Northern Sweden Health and Disease Cohort, enterolactone concentrations were measured in plasma obtained at a mean time of 5 years before diagnosis from 265 cases of prostate cancer, and from 525 matched controls. We found no significant association between plasma enterolactone and risk of prostate cancer. Men with very low enterolactone levels (bottom decile) however, had significantly higher risk of prostate cancer. Phytoestrogen rich diet including soy, rye bran, substances purified from rye, and a purified lignan (HMR) all inhibited prostate tumour growth. However, it cannot be concluded that the effects observed were due solely to lignans as other components in rye grain such as tannins, phytic acid, ferulic acid, vitamins and minerals may have contributed to the beneficial effects. Thus, additional studies are needed to further elucidate the effects of phytoestrogens on prostate cancer development and progression.

This dissertation consists of three projects in matched case-control studies. In the first project, we employ a general bias preventive approach developed by Firth (1993) to handle the bias of an estimator of the log-odds ratio parameter in conditional logistic regression by solving a modified score equation. The resultant estimator not only reduces bias but also can prevent producing infinite value. Furthermore, we propose a method to calculate the standard error of the resultant estimator. A closed form expression for the estimator of the log-odds ratio parameter is derived in the case of a dichotomous exposure variable. Finite sample properties of the estimator are investigated via a simulation study. Finally, we apply the method to analyze a matched case-control data from a low-birth-weight study. In the second project of this dissertation, we propose a score typed test for checking adequacy of a functional form of a covariate of interest in matched case-control studies by using penalized regression splines to approximate an unknown function. The asymptotic distribution of the test statistics under the null model is a linear combination of several chi-square random variables. We also derive the asymptotic distribution of the test statistic when the alternative model holds. Through a simulation study we assess and compare the finite sample properties of the proposed test with that of Arbogast and Lin (2004). To illustrate the usefulness of the method, we apply the proposed test to a matched case-control data constructed from the breast cancer data of the SEER study. Usually a logistic model is needed to associate the risk of the disease with the covariates of interests. However, this logistic model may not be appropriate in some instances. In the last project , we adopt idea to matched case-control studies and derive an information matrix based test for testing overall model adequacy and investigate the properties against the cumulative residual based test in Arbogast and Lin (2004) via a simulation study. The proposed method is less time consuming and has comparative power for small parameters. It is suitable to explore the overall model fitting.

Antro tipo cukrinis diabetas yra viena iš aktualiausių dabartinės medicinos problemų, kurios etiopatogenetinis pagrindas ypač glaudžiai siejasi su visuomenės papročiais ir gyvenimo būdu (WHO, 2006). Su gyvenimo būdu susietų rizikos veiksnių plėtra XX amžiuje įgavo epideminio pobūdžio metabolinių sutrikimų išraišką tarp atskirų, bet sąlyginai identiškai gyvenančių, individų grupių (King H. et al., 1998; Wild S. et al., 2004). Nepalankių socialinių ir ekonominių veiksnių įtaka ypač skatina metabolinių sutrikimų, kurie pasireiškia kaip metabolinis sindromas ir 2 tipo cukrinis diabetas, gausėjimą. Pasirinkus hipotezę, kad šiuolaikinės civilizacijos įpirštas gyvenimo būdas yra palankus 2 tipo cukrinio diabeto manifestavimui, prognozuojama, kad 2030 metais šia liga sirgs apie 366 milijonai planetos gyventojų (Wild S. et al., 2004). Metabolinių sutrikimų visuma įvardinta kaip „cukrinis diabetas” tampa vis dažnesne regėjimo sutrikimų, aklumo, kojų amputacijų, inkstų funkcijos nepakankamumo, blogos gyvenimo kokybės, prarasto darbingumo bei ankstyvesnio mirtingumo priežastimi. Tai – liga, esanti penktoje vietoje pagal mirtingumą po užkrečiamų, širdies ir kraujagyslių ligų, vėžio ir nelaimingų atsitikimų (Roglic G. et al., 2005). Lietuvoje cukrinio diabeto problema tampa vis aktualesnė, didėja sergančiųjų šia liga skaičius. Jei 1966 m. šalyje tebuvo suskaičiuotas 3561 sergantysis cukriniu diabetu (Sideraite Š., 1998), tai 1997 m. sausio 1 d. jau buvo užregistruoti 26896 sergantieji šia... [toliau žr. visą tekstą] / Diabetes mellitus is one of the main health issues in Lithuania. Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia, resulting from defects in insulin secretion, insulin action or both. The disease is associated with significant increased risk of long–term microvascular and macrovascular complications. The number of cases of diabetes worldwide in 2000 among adults 20 years of age is estimated to be 171 million. Diabetes is becoming a world pandemic with an estimated increase till 366 million cases by 2030, especially in developing countries. The number of people with diabetes is increasing due to population growth, aging, urbanization, and increasing prevalence of obesity . The aim of our study to assess clinical, laboratory data, risk factors and quality of life of new type 2 diabetes mellitus cases. A case–control study included 234 cases with newly confirmed diagnose of type 2 diabetes mellitus in 2001 and 468 controls who were free of the disease. Cases and controls were matched by gender and age (+5 yr.). Ratio of case and controls was 1:2. Two questionnaires were used in this study (1st one – to collect information on possible risk factors of type 2 diabetes mellitus, the 2nd one – EQ–5D questionnaire – to measure quality of life for patients with newly diagnosed type 2 diabetes mellitus). Variables were retained in models as confounders when inclusion changed the value of the odds ratio (OR) by more than 10% in any exposure category. The... [to full text]

Global spread of infectious disease threatens the well-being of human, domestic, and wildlife health. A proper understanding of global distribution of these diseases is an important part of disease management and policy making. However, data are subject to complexities by heterogeneity across host classes and space-time epidemic processes [Waller et al., 1997, Hosseini et al., 2006]. The use of frequentist methods in Biostatistics and epidemiology are common and are therefore extensively utilized in answering varied research questions. In this thesis, we proposed the Hierarchical Bayesian approach to study the spatial and the spatio-temporal pattern of tuberculosis in Kenya [Knorr-Held et al., 1998, Knorr-Held, 1999, L opez-Qu lez and Munoz, 2009, Waller et al., 1997, Julian Besag, 1991]. Space and time interaction of risk (ψ[ij]) is an important factor considered in this thesis. The Markov Chain Monte Carlo (MCMC) method via WinBUGS and R packages were used for simulations [Ntzoufras, 2011, Congdon, 2010, David et al., 1995, Gimenez et al., 2009, Brian, 2003], and the Deviance Information Criterion (DIC), proposed by [Spiegelhalter et al., 2002], used for models comparison and selection. Variation in TB risk is observed among Kenya counties and clustering among counties with high TB relative risk (RR). HIV prevalence is identified as the dominant determinant of TB. We found clustering and heterogeneity of risk among high rate counties and the overall TB risk is slightly decreasing from 2002-2009. Interaction of TB relative risk in space and time is found to be increasing among rural counties that share boundaries with urban counties with high TB risk. This is as a result of the ability of models to borrow strength from neighbouring counties, such that near by counties have similar risk. Although the approaches are less than ideal, we hope that our formulations provide a useful stepping stone in the development of spatial and spatio-temporal methodology for the statistical analysis of risk from TB in Kenya. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2013.

<p>Härtill 5 uppsatser</p> / digitalisering@umu