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Screening for New Primary Cancers in Cancer Survivors: Systematic Review and Analysis of Nova Scotian Colorectal Cancer SurvivorsCorkum, Mark 18 August 2011 (has links)
Little is known about the receipt of cancer screening for new primary cancers among Canadian cancer survivors. The objectives of this thesis are to i) synthesize evidence comparing receipt cancer screening between cancer survivors and non-cancer controls; and ii) analyze breast and cervical cancer screening receipt among Nova Scotian colorectal cancer (CRC) survivors. This thesis consists of a systematic review and meta-analysis, and a population-based cohort study of Nova Scotian CRC survivors. We found that while cancer survivors were more likely to receive cancer screening than the general population, a significant proportion of cancer survivors were not screened. We observed significant heterogeneity between studies, most of which remained unexplained after subgroup and sensitivity analyses. 30.1% and 47.9% of Nova Scotian CRC survivors never received a breast and cervical cancer screen after their CRC diagnosis. Receipt of pre-CRC diagnosis screening was strongly predictive of receiving screening post-diagnosis.
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Occurrence, determinants and dynamics of HPV coinfections in a cohort of Montreal university studentsSMITH, MICHAELA ANNE 21 April 2011 (has links)
Background: Coinfections with multiple types of human papillomavirus (HPV) are a common occurrence among HPV-infected individuals, but the clinical significance and etiology of these infections remain unclear. Though current evidence suggests that women with coinfections have increased HPV exposure (i.e. more sexual partners), it is also hypothesized that these women may represent a subgroup with increased HPV susceptibility, though this has been rarely studied to date.
Purpose: The purpose of this project was to examine the occurrence, determinants and dynamics of HPV coinfections in a cohort of university students in order to explore the relationship(s) between coinfections, lifestyle factors and immunological susceptibility.
Methods: This project is based on a secondary analysis of data from the McGill-Concordia Cohort, a longitudinal study of the natural history of HPV infection in 621 female university students in Montreal, Quebec. Participants were followed for 2 years at 6-month intervals. At each visit, cervical specimens were collected for cytology and HPV testing, and women completed a questionnaire about lifestyle and risk behaviours. Two definitions of coinfections were used: cumulative coinfection over follow-up and concurrent coinfection at each visit. Kaplan-Meier techniques were used to estimate incidence and duration of coinfections and multiple logistic regression was used to identify determinants of coinfections and associations between coinfections and squamous intraepithelial lesions (SIL).
Results: More than half of the cohort became infected with HPV and of those, over 60% acquired multiple HPV types over follow-up. Incidence of coinfections was significantly increased among HPV-infected women at enrollment. The most important determinant of coinfection occurrence was number of sexual partners (both lifetime and new), though some genes of the immune response (HLA-DQB1*06:02, HLA-G*01:01:03 and HLA-G*01:01:05) were also significant predictors. Women with coinfections, particularly those with 4+ HPV types, also had longer infection durations and greatly increased odds of SIL.
Conclusions: Women with coinfections acquire new HPV types at an increased rate and have greater HPV persistence and occurrence of SIL, which may indicate immunological susceptibility. HPV coinfections mainly occur due to increased sexual activity but a decreased immune response to the virus may also be involved in a subset of women. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2011-04-21 01:04:26.265
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Risk factors for injury in men´s professional footballKristenson, Karolina January 2015 (has links)
This thesis includes four papers based on three different prospective cohort studies on injury characteristics in men’s professional football. The same general methodology was used in all papers. Time-loss injuries and player individual exposure was registered for match and training separately. The general aim was to investigate potential internal and external risk factors for injury, with a focus on age, playing position, time in professional football, playing surface (artificial turf and natural grass), changes between surfaces and climate; and to evaluate the study methodology. Paper I was based on data collected between 2001 and 2010 from 26 top professional clubs in Europe; the UCL injury study. In total, 6140 injuries and 797 389 hours of exposure were registered. A decreased general injury rate was observed for newcomers compared with established players (hazard ratio (HR), 0.77; 95% CI 0.61-0.99). Using goalkeepers as a reference, all outfield playing positions had significantly higher age-adjusted injury rates. Using players aged ≤ 21 years as a reference, the overall adjusted injury rate increased with age, with a peak injury rate among players aged 29 to 30 years (HR, 1.44; 95% CI, 1.24-1.68). Paper II and Paper III are based on data collected during two consecutive seasons, 2010 and 2011, in the Swedish and Norwegian male first leagues. In total, 2186 injuries and 367 490 hours of football exposure were recorded. No statistically significant differences were found in acute injury rates on artificial turf (AT) compared with natural grass (NG) during match play (rate ratio, 0.98, 99% CI 0.79-1.22) or training (rate ratio 1.14, 99% CI 0.86-1.50) when analysing at the individual player level. However, when analysing at the club level, clubs with AT installed at their home arena had a significantly higher acute training injury rate (rate ratio 1.31, 99% CI 1.04-1.63) and overuse injury rate (rate ratio 1.38, 99% CI 1.14-1.65) compared to clubs with NG installed at their home venue. No association was found between frequent surface shifts and subsequent overuse injury risk (risk ratio 1.01, 95% CI 0.91-1.12). Analyses on the total cohort showed no difference in injury rates between clubs in the two climate zones (total rate ratio 1.01, 95% CI 0.92-1.10). Data included in Paper IV were collected during two consecutive seasons 2008 and 2009. During this period, two Norwegian elite football clubs were concurrently included in two research groups’ surveillance systems. The capture rate for match injuries was similar between the two audits, while the capture rate for training injuries was slightly higher with individual-based exposure recording. The inter-rater agreement in injury variable categorisations was in most aspects very high.
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Health-Related Quality of Life and Return to Work following Breast CancerLundh, Marie Høyer January 2014 (has links)
Aim: The overall aim of this thesis was to study health-related quality of life (HRQoL) and return to work in the first 3 years following a breast cancer diagnosis, and to identify clinical and contextual factors associated with these outcomes. Method: The four studies were part of a population-based cohort study including women identified in the Breast Cancer Quality Register in central Sweden. Of 1,573 women asked to participate, 69% (n=1,093) responded to a baseline questionnaire, 62% (n=977) responded at the 1st follow-up and 54% (n=856) participated at the 2nd follow-up (mean time 4, 16 and 38 months post-diagnosis, respectively). Studies II and IV only included women aged <63 years at diagnosis. In Study IV, each woman was individually matched to five breast-cancer-free controls. Questionnaire data on HRQoL, socio-demographics and work-related variables were combined with clinical register, normative and social insurance data. Main findings: Study I: Women with breast cancer, particularly women aged <50 years, experienced poorer HRQoL at baseline than normative data. Chemotherapy, lack of social support, sick leave and a poor financial situation were associated with poorer HRQoL. Study II: Compared with pre-diagnosis working time, 72% of participating women reported no change, 2% had increased their working time, 15% reported a decrease in working time and 11% did not work at the 1st follow-up. Chemotherapy, cancer-related work limitations and less value attached to work increased the odds of job discontinuation/decreased working time. Study III: During the 3 years post-diagnosis, HRQoL generally improved. Less consistent improvements were found among women on sick leave/disability pension pre-diagnosis and women reporting job discontinuation/decreased working time post-diagnosis. Study IV: The proportion of women with breast cancer on sick leave steadily decreased during the 3 years post-diagnosis, but they were more likely to be on sick leave than the controls. Chemotherapy, fatigue and pre-diagnosis sick days predicted sickness absence during the 2nd and 3rd year post-diagnosis. Conclusions: Most women with breast cancer gradually recover, but there are subgroups of women who may be particularly vulnerable. In a clinical setting, increased attention should be directed towards women undergoing chemotherapy, young women, women on sick leave/disability pension pre-diagnosis and women who do not return to work to the same extent as pre-diagnosis.
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Diagnosing DVT in the Emergency Department: Combining Clinical Predictors, D-dimer and Bedside UltrasoundBlecher, Gabriel E. 05 April 2013 (has links)
I assessed the accuracy of two clinical prediction rules, the d-dimer blood test and point of care ultrasound for diagnosing lower limb deep vein thrombosis.
Emergency physicians were trained in ultrasound and prospectively scanned emergency department patients with suspected deep vein thrombosis. Accuracy of the Wells and AMUSE rules and the ultrasound result was compared to radiology-performed ultrasound and a 90-day clinical outcome. Univariate and multivariate analyses were performed assessing which factors were associated with the outcome.
The sensitivity and specificity of the Wells score for the clinical outcome was 85.7% and 68.5%; the AMUSE score 85.7% and 54.4%. Ultrasound had a sensitivity of 91.7% and specificity of 91.7% for radiology-diagnosed thrombus and 78.6% and 95.0% for clinical outcome. The odds ratio of a positive outcome with a positive ultrasound was 65.1.
After receiving the ultrasound training program, emergency physicians were unable to demonstrate sufficient accuracy to replace current diagnostic strategies.
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Psykisk hälsa som klassmarkör : En kvantitativ studie av socioekonomisk klassposition och schizofreni.Strandendahl, Louise, Löfgren Jarl, Emilie January 2015 (has links)
Syftet med föreliggande kvantitativa studie är att undersöka sambandet mellan socioekonomisk klassposition i vuxenlivet och risken att vårdas för schizofreni. Sambandet mellan klassposition och hälsa kan ta sig uttryck i två riktningar - något som avhandlas i kausalitetsteorin och selektionsteorin. Kausalitetsteorin utgår från att en individs klassposition påverkar ens framtida hälsa, där en lägre klassposition riskerar att leda till sämre hälsa. I kontrast till detta utgår selektionsteorin från att en individs hälsa påverkar klasspositionen, där ohälsa tenderar att leda till en lägre klassposition. Dessa teorier utgör föreliggande studies teoretiska utgångspunkt. Datamaterialet som används är “Stockholm Birth Cohort” (SBC), vilket är resultatet av en sannolikhetsmatchning mellan två avidentifierade material. Materialet består av longitudinell kohortdata som sträcker sig från år 1953 till år 2008. Analysmetoden i föreliggande studie är multipel logistisk regressionsanalys vilket är lämpligt då utfallsvariabeln har gjorts binär. Resultatet som nås är att det existerar ett signifikant samband mellan socioekonomisk klassposition i vuxenlivet och risken att vårdas för schizofreni, även när sambandet kontrollerats för föräldrarnas socioekonomiska klassposition, psykiska hälsa, utbildning, inkomst, alkoholmissbruk samt familjetyp och kohortmedlemmens kön. Då denna infallsvinkel är relativt outforskad är detta resultat därför ett relevant bidrag till forskningsfältet. Vidare har försök gjorts att undersöka riktningen på detta samband och utifrån genomförda tester verkar det som att både kausalitets- och selektionsteorin har ett förklaringsvärde beroende på ifall klassposition mäts utifrån föräldrarnas eller individens klassposition. Rimligtvis är socioekonomisk klassposition och schizofreni ömsesidigt sammanlänkande över individens livsförlopp.
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Does Duration of Nicotine Replacement Therapy Use Matter in Quitting Smoking? A Longitudinal Study of Smokers in the General PopulationZhang, Bo 13 August 2013 (has links)
Background and Objectives: Little is known about the impact of nicotine replacement therapy (NRT) use duration on smoking cessation in the general population. This study determines whether duration of NRT use is associated with smoking cessation.
Methods: Data were from the Ontario Tobacco Survey longitudinal study of a population-based cohort of baseline smokers who made serious quit attempts during 18 months of follow-up. The association between NRT (any NRT, patches, or gum) use duration and smoking cessation outcomes (short-term abstinence ≥1 month and long-term abstinence ≥12 months) was estimated by Poisson regression, adjusting for all confounding variables.
Results: Among the 1,590 eligible smokers, 933 (59%) did not use any NRT, 535 (34%) used NRT <8 weeks, and 112 (8%) used NRT ≥8 weeks at follow-up. The median duration of NRT use was 14 days. A consistent “J” shape of associations between quit aid use duration and smoking cessation outcomes (quit rates) was found. Using any NRT, patches, or gum <8 weeks was generally associated with a lower likelihood of quitting, but using them ≥8 weeks was generally associated with a higher likelihood of quitting, compared to not using them. Only using patches for the recommended duration (≥8 weeks) was associated with a higher likelihood of short-term (relative risk, RR 1.74, 95% confidence interval, CI 1.21-2.50) and long-term (RR 2.62, 95% CI 1.25-5.50) abstinence at the end of 18 months of follow-up, compared to not using patches. Using gum ≥8 weeks was not associated with short- or long-term abstinence at the end of 18 months of follow-up.
Conclusions: Using nicotine patches for the recommended duration is associated with successful short- and long-term abstinence in the general population. More efforts are needed to encourage smokers to use nicotine patches for eight or more weeks when attempting to quit.
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Does Duration of Nicotine Replacement Therapy Use Matter in Quitting Smoking? A Longitudinal Study of Smokers in the General PopulationZhang, Bo 13 August 2013 (has links)
Background and Objectives: Little is known about the impact of nicotine replacement therapy (NRT) use duration on smoking cessation in the general population. This study determines whether duration of NRT use is associated with smoking cessation.
Methods: Data were from the Ontario Tobacco Survey longitudinal study of a population-based cohort of baseline smokers who made serious quit attempts during 18 months of follow-up. The association between NRT (any NRT, patches, or gum) use duration and smoking cessation outcomes (short-term abstinence ≥1 month and long-term abstinence ≥12 months) was estimated by Poisson regression, adjusting for all confounding variables.
Results: Among the 1,590 eligible smokers, 933 (59%) did not use any NRT, 535 (34%) used NRT <8 weeks, and 112 (8%) used NRT ≥8 weeks at follow-up. The median duration of NRT use was 14 days. A consistent “J” shape of associations between quit aid use duration and smoking cessation outcomes (quit rates) was found. Using any NRT, patches, or gum <8 weeks was generally associated with a lower likelihood of quitting, but using them ≥8 weeks was generally associated with a higher likelihood of quitting, compared to not using them. Only using patches for the recommended duration (≥8 weeks) was associated with a higher likelihood of short-term (relative risk, RR 1.74, 95% confidence interval, CI 1.21-2.50) and long-term (RR 2.62, 95% CI 1.25-5.50) abstinence at the end of 18 months of follow-up, compared to not using patches. Using gum ≥8 weeks was not associated with short- or long-term abstinence at the end of 18 months of follow-up.
Conclusions: Using nicotine patches for the recommended duration is associated with successful short- and long-term abstinence in the general population. More efforts are needed to encourage smokers to use nicotine patches for eight or more weeks when attempting to quit.
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Low Back Pain : With Special Reference to Prevalence, Diagnosis, Treatment and PrognosisBogefeldt, Johan January 2009 (has links)
Objectives. Ascertain if there has been a secular trend in 3-months prevalence of casually reported back pain. Evaluate if such back pain predicts concurrent health as well as future sick leave, disability pension, hospitalization and survival. Study differences in diagnostic assessment and labelling between physicians. Evaluate if a comprehensive manual therapy programme reduces sickness absence. Materials and methods. Combined population samples from 1973 to 2003 with a total of 12,891 observations with self-reported back pain and covariates. 7,074 of these individuals were followed for an average of 8.5 years and outcomes were self-reported health as well as official register data on sick leave, disability pension, hospitalisation and mortality. The Gotland Low Back Pain Study, a randomised controlled trial with participation of two general practitioners and two orthopaedic surgeons treating 160 patients with acute/subacute low back pain, with 10 weeks diagnostic evaluation and treatment and a two-year follow up. Results. Back pain prevalence increased 16% per ten years (OR 1.16, 95%CI 1.11-1.22). Back pain was negatively associated with self-rated health (p<0.0001), increased the risk of disability pension (p<0.002), and hospital admissions (p<0.0005), but not number of days in hospital, sick leave or mortality. General practitioners used terms from manual medicine and reported more pseudoradicular pain, while orthopaedic surgeons used non-specific pain labels, reported more true radicular pain and used more x-ray examinations. Among those on sick leave at baseline, manual therapy patients showed faster return to work (HR 1.62, 95%CI 1.006–2.60) and a lower point-prevalence of sick leave than reference patients at end of treatment period (ratio 0.35, 95% CI 0.13–0.97) but not after two years. Conclusions. There was a strong secular trend towards increase in self-reported back pain from 1973 to 2003. Such pain had a negative effect on some of the health outcomes and does not appear to be harmless. Physicians from different specialities labelled the condition differently. The manual therapy programme proved to be more effective than the established treatment regarding return to work.
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Impacto da estratégia de tratamento baseado em metas em pacientes com artrite reumatóide estabelecida : estudo de coorte prospectivaAndrade, Nicole Pamplona Bueno de January 2015 (has links)
Introdução: A estratégia de tratamento baseado em metas tem sido extensamente estudada em pacientes com AR inicial. No entanto, estudos sobre os benefícios de longo prazo do controle de atividade de doença em pacientes com AR estabelecida ainda são escassos. Objetivo: Avaliar a efetividade de longo prazo da estratégia de tratamento baseado em metas em pacientes com artrite reumatoide estabelecida na prática diária. Métodos: Pacientes com AR, previamente tratados de forma convencional, iniciaram estratégia de tratamento baseado em metas, sendo incluídos de março de 2005 a fevereiro de 2007 e acompanhados até dezembro de 2014. Os pacientes eram avaliados a cada 3 meses até remissão ou baixa atividade de doença serem alcançadas, e após a cada 6 meses. O tratamento seguiu um escalonamento de acordo com as recomendações vigentes. A atividade de doença foi mensurada através do DAS28 e do CDAI e a capacidade funcional, através do HAQ-DI. As informações foram extraídas pela revisão de formulários e de tabelas padronizadas. Variações na atividade de doença e na capacidade funcional foram comparadas pelo teste de Wilcoxon e Equações de Estimativas Generalizadas (GEE) A mortalidade foi avaliada através da curva de Kaplan-Meier. Resultados: Duzentos e vinte e nove pacientes foram incluídos, com duração média de doença 10,6±7,4 anos. Dentre os pacientes em moderada e alta atividade de doença no início da coorte, houve significativa redução do DAS28 (4,6±0,1 vs. 3,1±0,1; p<0,001) e do CDAI (21,2±1,0 vs. 7,9±0,7; p<0,001). Também houve redução do HAQ-DI (1,3±0,05 vs 1,0±0,1; p<0,001). A proporção de pacientes em remissão ou em baixa atividade de doença aumentou de 20% para 62% pelo DAS28. Com a estratégia de tratamento baseado em metas, houve um aumento na proporção de pacientes em uso de biológico para 30%. A taxa de mortalidade foi de 24,2 por 1000 pacientes-ano, discretamente superior à descrita na literatura. Conclusão: A estratégia de tratamento baseado em metas com objetivo de remissão e de baixa atividade de doença é efetivo em pacientes com AR estabelecida. / Introduction: Treating RA to a target has become a landmark strategy to be pursued in every patient. Nonetheless, few studies have addressed the true long-term impact of a T2T strategy in a real-world setting with established RA patients. Objective. To examine the long-term effectiveness of a treat-to-target (T2T) strategy in patients with established rheumatoid arthritis (RA) in daily practice. Methods. Patients with RA who were previously given the standard of care were started on a T2T strategy between March 2005 and February 2007 and followed through December 2014. Participants were seen every 3 months until remission/low disease activity was achieved and every 6 months thereafter. Treatment escalation followed a step-up strategy, according to national recommendations. Disease activity was measured by the DAS28 score and Clinical Disease Activity Index (CDAI), and physical function by the Health Assessment Questionnaire (HAQ). Data were extracted with standardized forms and a chart review. Changes in disease activity and physical function were compared using Wilcoxon’s test and generalized estimating equations. Mortality was analyzed using a Kaplan–Meier survival curve. Results. Two hundred and twenty-nine patients were included, with a mean (S.D.) disease duration of 10.6 (7.4) years. Significant reductions were observed in DAS28 (4.6±0.1 vs. 3.1±0.1; p<0.001), CDAI (21.2±1.0 vs. 7.9±0.7; p<0.001), and HAQ (1.3±0.05 vs 1.0±0.1; p<0.001) scores. The proportion of participants in remission/with low disease activity according to DAS28 increased from 20% to 62%. During implementation of the T2T strategy, a gradual increase in the proportion of participants using biologics was observed, to nearly 30%. The mortality rate was 24.2 per 1000 patient-years, slightly higher than that reported in other cohorts. Conclusion. A treat-to-target strategy aiming for remission or low disease activity is effective in patients with established RA.
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