Whereas first line therapy for chronic obstructive pulmonary disease (COPD) usually includes a short-acting bronchodilator, there are suggestions that these agents may increase the risk of cardiac arrhythmias. In this thesis, we first assessed the risks associated with short-acting beta-agonists (SABA), long-acting beta-agonists (LABA), ipratropium bromide (IB), and methyl xanthines (MX) within a cohort of COPD patients using the health databases of Saskatchewan. In order to confirm these findings and to address some methodological issues we then replicated this analysis within a larger cohort of patients using the health databases of Quebec. / Our first study cohort consisted of 6,018 adults aged 55 and older, newly treated with bronchodilator medications. We found that new users of both IB and LABA increased the risk of arrhythmia (RR 2.39 [95% CI 1.42-4.05] and (RR 4.55 [95% CI 1.43-14.45] respectively). When the cohort was restricted by excluding subjects who had recently either been hospitalised or experienced an exacerbation, the elevated risk associated with the new use of IB persisted (RR 3.65 [95% CI 1.72-7.74]), an effect was detected with new use of MX (RR 5.17 [95% CI 1.38-19.30]), but there was insufficient power to detect an effect associated with the new use of LABA. / Due to both power issues and the limited availability of LABA within the Saskatchewan data, we replicated the analysis in a larger new-user cohort of 76,661 Quebec adults aged 67 and over. This study confirmed our earlier results, with an elevated risk of arrhythmia associated with the new use of both IB and LABA (RR 1.43 [95% CI 1.08-1.88]) and (RR 1.54 [95% CI 1.00-2.36]) respectively, as well as with new use of SABA (RR 1.28 [95% CI 1.02-1.61]). Finally, using marginal structural models, we demonstrated that both exacerbations of COPD as well as minor non-event arrhythmias were moderate time-dependent confounders within this setting. / In conclusion, we found that new use of bronchodilators in COPD, particularly IB and LABA, was associated with an increase in the risk of cardiac arrhythmias. We also demonstrated the method by which the time-dependent confounder status of specific model covariates may be evaluated.

Many epidemiological studies assess the effects of time-dependent exposures, where both the exposure status and its intensity vary over time. The analysis of such studies poses the challenge of modelling the association between complex time-dependent drug exposure and the risk, especially given the uncertainty about the etiological relevance of doses taken in different time periods. / To address this challenge, I developed a flexible method for modelling cumulative effects of time-varying exposures, weighted by recency, represented by time-dependent covariates in the Cox proportional hazards model. The function that assigns weights to doses taken in the past is estimated using cubic regression splines. Models with different number of knots and constraints are estimated. Bootstrap techniques are used to obtain pointwise confidence bands around the weight functions, accounting for both the sampling variation of the regression coefficients, and the uncertainty at the model selection stage, i.e. the additional variance due to a posteriori selection of the number of knots. / To assess the method in simulations, I had to develop and validate a novel algorithm to generate event times conditional on time-dependent covariates and compared it with the algorithms available in the literature. The proposed algorithm extends a previously proposed permutational algorithm to include a rejection sampler. While all the algorithms generated data sets that, once analyzed, provided virtually unbiased estimates with comparable variances, the algorithm that I proposed reduced the computational time by more than 50 per cent relative to alternative methods. I used simulations to systematically investigate the properties of the weighted cumulative dose method. Six different weight functions were considered. Simulations showed that in most situations, the proposed method was able to capture the shape of the true weight functions and to produce estimates of the magnitude of the exposure effect on the risk that were close to those used to generate the data. I finally illustrated the use of the weighted cumulative dose modelling by reassessing the association between the use of selected benzodiazepines and fall-related injuries, using administrative data on a cohort of elderly who initiated their use of benzodiazepines between 1990 and 2004.

Introdução. As hemisferectomias são cirurgias utilizadas há décadas para se tratar epilepsias refratárias à medicação anticonvulsivante. Embora o controle das crises seja satisfatório, a morbidade, per e pós-operatória, ainda é considerada um importante fator limitante à sua utilização. Dessa maneira, compreender as complicações mais comuns do procedimento, e os fatores que as influenciam, é essencial para se estabelecer o melhor uso para a técnica. Métodos. Foram coletados dados de 30 pacientes, operados por seis cirurgiões no Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo no período entre 1980 e 2003. Foram realizadas 11 hemisferectomias com a abordagem de Rasmussen, três hemisferectomias anatômicas, nove hemisferectomias funcionais extraventriculares e sete hemisferotomias. Foram estudados cinco grupo de pacientes de acordo com a fisiopatologia da doença de base: Dezesseis pacientes eram portadores de Síndrome de Rasmussen, dois da Síndrome de Sturge-Weber, quatro de malformações corticais, dois de lesões sequelares e seis de cistos porencefálicos. Os fatores de morbidade foram avaliados dentro de rês perspectivas: 1- da doença de base; 2- da técnica utilizada; e 3- do fator humano. Resultados. Nossos dados mostraram ausência de diferença estatisticamente significativa entre as técnicas cirúrgicas empregadas nos itens: tempo cirúrgico; tempo de internação na unidade de terapia intensiva; queda da hemoglobina; volume de hemoderivados transfundidos e febre no pós-operatório. Presença de leucograma acima de 15.000 leucócitos/mm3 no pós-operatório imediato foi associada a estadias mais longas na unidade de terapia intensiva A média diária de temperatura dos pacientes, mostrou temperaturas acima de 38º C entre o terceiro e sexto dia pós-operatório. Pacientes com hemimegalencefalia apresentaram temperaturas mais elevadas quando comparados com os portadores de cistos porencefálicos. Doenças com maior manto cortical contribuíram para aumentar o tempo cirúrgico, embora o fator humano tenha sido decisivo nesse item. Ao comparar nossos achados com os da literatura, vimos que os pacientes submetidos à hemisferectomia anatômica apresentaram no pós-operatório temperaturas mais elevadas e reação inflamatória liquórica mais intensa que os submetidos a técnicas de desconexão hemisférica, no entanto, a importância desse dado necessita ser estabelecida. Conclusões: O principal fator de morbidade nas hemisferectomias é a doença de base, assim, os dados presentes na literatura, incluindo nossa casuística, não nos permite concluir que uma técnica seja superior à outra ou que as técnicas desconectivas sejam melhores que as ressectivas / Hemispherectomy has been the treatment of choice in some sorts of refractory epilepsies for decades. Although surgery results in satisfactory control of seizures, its morbidity remains a major concern. Thus, understanding most common complications, as well as the factors that contribute to it, becomes an essential step to learn the limits on technique applications. Methods. Hospital charts from 30 patients operated on by six different surgeons at the Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo from 1980 to 2003 were reviewed. Eleven functional hemispherectomies using Rasmussen approach, three anatomical hemispherectomies, nine extraventricular functional hemispherectomies, and seven hemispherotomies were included in this study. Sixteen patients presented with Rasmussen Syndrome, two Sturge-Weber Syndrome, four cortical malformations, two hemispheric lesions, and six porencephalic cysts. Morbidity was evaluated from three different perspectives 1- background disease, 2- employed technique, and 3- human factor. Results: our data presented no statistical difference among the employed techniques regarding 1- surgical time, 2- intensive care unit time, 3- per and postoperative fall of hemoglobin, 4- blood transfusion volume, and 5- postoperative axilar temperature variation. Patients that presented over 15,000 leucocytes per mm3 stayed longer at the intensive care unit, regardless of the surgical technique employed. Daily average temperatures varied around 38 degrees Celsius from the third to the sixth postoperative day. Patients with hemimegalencephaly had higher postoperative axilar temperatures when compared to those with porencephaly. Thicker cortical mantle contributed to increase surgical time, though human factor also showed to be important in this item. Comparing data from this study and the literature disclosed that patients undergoing anatomical hemispherectomies presented an inflammatory response in the cerebrospinal fluid more evident than those submitted to cerebral disconnection, although the importance of this finding is still elusive. Conclusions: The main factors of morbidity in the hemispherectomy are the background disease and patient\'s peculiarities, therefore, it is not reasonable to infer that there is a superior technique or that hemisphere disconnection is better than removal

No description available.

No description available.

Indiana University-Purdue University Indianapolis (IUPUI) / Hypothesis: The interaction between the abrasive level and fluoride concentration of dentifrice slurries modulates the surface loss (SL) and remineralization of incipient enamel caries (IEC). Methods: Three types of IEC were created and six experimental slurries with different combinations of fluoride content and abrasive level were tested. In experiment 1, the three IEC were subjected to brushing (with experimental slurries) and remineralization cycles for 5 days. Fluoride concentrations (0 and 275 ppm as NaF) and abrasive levels (Low and High) were tested. SL was determined by optical profilometry at baseline and after 1, 3, and 5 days. In experiment 2, changes in IEC mineral content (Δ(ΔZ)C) and depth (ΔLC) were investigated at baseline and after the 5-day cycling with transverse microradiography. In experiments 3 and 4, SL of MeC and CMC lesions were further studied, respectively; testing not only fluoride concentration (275 and 1250 ppm as NaF) and abrasivity (low and high) of the slurry, but also the brushing frequency (1x, 2x, and 3x/day). Brushing-remineralization cycles were performed for 7 days. Statistical analyses were performed at 5% significance level. Results: Experiment 1: overall, brushing with the high-abrasive slurry caused more SL than with the low-abrasive. For CMC and MeC lesions, 0 ppm F had more SL than 275 ppm F only after day 3. Fluoride had no effect on the SL of HEC lesions. Experiment 2: fluoride and abrasives did not have a significant effect on IEC. HEC had significantly lower Δ(ΔZ)C than CMC and MeC, with CMC and MeC not differing from each other. Lesion type had no effect on ΔLC. Experiment 3: brushing CMC lesions 3x/day with 1250 ppm F increased SL compared to 1x/day, after 5 and 7 days. Study 4: brushing MeC lesions with high abrasive slurry containing 1250 ppm F increased SL after 5 and 7 days. Conclusions: The IEC tested showed different SL and remineralization behaviors. The fluoride content and abrasive level of the toothpaste showed to be relevant modulating the SL of enamel caries lesions as well as their remineralization behavior.

No description available.

Background: Prostate cancer is the most common type of cancer in Sweden. The three primary treatment types for prostate cancer are prostatectomy, radiotherapy and different types of endocrine therapy. With all treatments mentioned above comes adverse effects that may have big effects on the person treated. Aim: The aim of this study was to highlight men´s experiences of the adverse effects that comes with the treatment for prostate cancer. Method: The research method employed was a literature study based on eleven qualitative articles. The method of analysis was done according to Friberg five-step analysis of qualitative articles and through the analysis, six themes emerged. Results: The themes were A feeling of emotional imbalance, Not prepared enough, The experience of loosing control, Feeling of diminished masculinity, The experience of a feminized body and An altered identity. Conclusion: The result showed that men experience adverse effects of the prostate cancer treatment as difficult in many ways. The changes to the body and mental well-being tend to be difficult to deal with, and the men need relevant information prior to treatment to give them time to adjust to their new life.

Recent research on psychotherapeutic outcome has highlighted cognitive behaviour therapy (CBT) as the preferred psychotherapeutic approach for most psychological problems. There is however considerable evidence supporting the comparative effectiveness of approaches alternative to CBT. Central to this alternative evidence base is the notion that ‘personal styles’ are influential in determining individual preferences for different psychotherapeutic approaches. This study examined the effect of the combination between the ‘personal style’ of the client and the type of psychotherapeutic approach they receive (more or less directive) on the client’s experience of therapy. A second aim of this study was to explore similarities and differences in the way clients with different 'personal styles' construe therapy through analysis of repertory grid data. Thirty participants with diagnoses of anxiety and/or depression were recruited from mental health charities and a local NHS community team. Participants completed a questionnaire measuring the direction of interest element of personal style, a self-report questionnaire rating their experience of psychotherapy and a repertory grid exploring their construing of psychotherapy. The study found that the fit between an individual’s ‘personal style’ and the type of therapeutic approach they received was predictive of therapy experience. Analysis of the repertory grids revealed few differences in the construing of participants with different ‘personal styles’. The use of a global measure of therapeutic experience was original in research looking at the helpful aspects of psychotherapy. The strengths and limitations of the study are discussed and ideas for future research are recommended.

Background Screening for prostate cancer is debated, there is conflicting data on the net benefit of screening. Men who consider screening need to be informed on the pros and cons. Rehospitalization after surgery can be used as an indicator of general quality of care. For radical prostatectomy, little is known on the readmission rate after surgery. Men diagnosed with low- and intermediate-risk prostate cancer have low prostate-cancer specific mortality. However, adverse effects after curative treatment can be severe and decrease quality of life. Curative treatments for prostate cancer differ mainly in the pattern of adverse effects but detailed analysis of long-term adverse effects is lacking. The aim of this thesis was to assess the perioperative quality of radical prostatectomy and the risk of adverse effects after curative treatment for prostate cancer. Material and Methods In this thesis, data from the National Prostate Cancer Register (NPCR) and other nationwide Swedish registers were used. By use of the Swedish personal identity number, NPCR was cross-linked to other registers creating Prostate Cancer data Base Sweden (PCBaSe), a large dataset for research. Results The proportion of men who had received information on the pros and cons of screening for prostate cancer with PSA testing was low (14%) indicating that the majority of men who were screened did not make an informed decision. The risk of rehospitalization within 90 days after radical prostatectomy was approximately 10% and similar after retropubic and robot-assisted radical prostatectomy. Compared to controls, there was an increased risk of adverse effects after both radiotherapy and radical prostatectomy up to twelve years after treatment and the overall risk was quite similar after retropubic and robot-assisted radical prostatectomy. Conclusion Improved information to men on the pros and cons of PSA screening is warranted. The risk of adverse effects was elevated up to 12 years after curative treatment for prostate cancer. The pattern of adverse effects was different after radiotherapy and radical prostatectomy but quite similar after retropubic and robot-assisted radical prostatectomy.