Background: Cesarean delivery rates have been increasing since 1996, and Cesarean delivery is now the most common major operative procedure performed in the United States. Identifying risk factors for wound complications following Cesarean delivery is necessary to prevent unnecessary maternal morbidity. Methods: A case-control study was carried out and data was collected via a medical record review for patients undergoing a Cesarean delivery at the UIHC between 10/1/2011 and 12/31/2012. Results: Several modifiable risk factors were identified, and models based on patient and surgical factors performed better than the current standard NHSN risk index model. Conclusion: More robust prediction models can be created using patient and surgical factors.

Approximately 2-11% of adolescents report chronic insomnia. The study used an archival data set from ADDHealth that assessed adolescent health and health-related behaviors. Adolescents (N = 4102) provided data at baseline (Time 1) and at 1-year follow-up (Time 2). Participants were excluded if no ethnicity, gender, or insomnia data were given at Time 1 or 2. Females were more likely to report insomnia than males at Times 1 and 2. In addition, adolescents with remitted insomnia were significantly younger than adolescents without insomnia at Times 1 and 2. Analyses found a prevalence of 9.6%, a remittance of 6.2%, an incidence of 4.4%, and a chronicity of 2.9%. At Time 1 and 2, AWI were significantly more likely to have depression, suicidal behaviors, and behavioral problems in school than AWOI. At Time 2, incidence and chronic insomnia increased the risk of depression, suicidal behaviors and behavioral problems in school. Risk and protective factors analyses indicated psychological counseling was associated with both remitted and chronic insomnia and depression was associated with incidence insomnia.

BACKGROUND:Delay in seeking care is a major impediment to effective management of tuberculosis (TB) in China. To elucidate factors that underpin patient and diagnostic delays in TB management, we conducted a systematic review and meta-analysis of factors that are associated with delays in TB care-seeking and diagnosis in the country.METHODS:This review was prepared following standard procedures of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and checklist. Relevant studies published up to November 2012 were identified from three major international and Chinese literature databases: Medline/PubMed, EMBASE and CNKI (China National Knowledge Infrastructure).RESULTS:We included 29 studies involving 38,947 patients from 17 provinces in China. Qualitative analysis showed that key individual level determinants of delays included socio-demographic and economic factors, mostly poverty, rural residence, lack of health insurance, lower educational attainment, stigma and poor knowledge of TB. Health facility determinants included limited availability of resources to perform prompt diagnosis, lack of qualified health workers and geographical barriers.Quantitative meta-analysis indicated that living in rural areas was a risk factor for patient delays (pooled odds ratio (OR) (95% confidence interval (CI)): 1.79 (1.62, 1.98)) and diagnostic delays (pooled OR (95% CI): 1.40 (1.23, 1.59)). Female patients had higher risk of patient delay (pooled OR (95% CI): 1.94 (1.13, 3.33)). Low educational attainment (primary school and below) was also a risk factor for patient delay (pooled OR (95% CI): 2.14 (1.03, 4.47)). The practice of seeking care first from Traditional Chinese Medicine (TMC) providers was also identified as a risk factor for diagnostic delay (pooled OR (95% CI): 5.75 (3.03, 10.94)).CONCLUSION:Patient and diagnostic delays in TB care are mediated by individual and health facility factors. Population-based interventions that seek to reduce TB stigma and raise awareness about the benefits of early diagnosis and prompt treatment are needed. Policies that remove patients' financial barriers in access to TB care, and integration of the informal care sector into TB control in urban and rural settings are central factors in TB control.

Background Asthma and chronic obstructive pulmonary disease (COPD) are common obstructive airway diseases with a substantial burden in terms of morbidity, mortality and costs. Smoking is the single most important risk factor for COPD, and is associated with incident asthma. It is important to know if the prevalence of asthma and COPD is increasing or decreasing in the population in order to effectively allocate health care resources. The definitions of these diseases have varied over time which makes it difficult to measure changes in prevalence. The preferred method is to estimate the prevalence with the same procedures and definitions based on cross-sectional population samples with identical age distributions in the same geographical area at different time points. Measurements of lung function (spirometry) are required to diagnose COPD, and spirometry is used to evaluate disease severity and progress of both asthma and COPD, where observed values are compared to reference values. The most commonly used reference values in Sweden are published during the mid 1980s, and there are few evaluations of how appropriate they are today based on Swedish population samples. The aim of the thesis was to estimate trends in the prevalence of asthma and COPD in relation to smoking habits, and to evaluate and estimate reference values for spirometry. Methods The project was based on population-based samples of adults from the Obstructive Lung Disease in Northern Sweden (OLIN) studies. Postal questionnaires were sent to large cohorts, recruited in 1992 (n=4851, 20-69 years), 1996 (n=7420, 20-74 years) and 2006 (n=6165, 20-69 years), respectively. The questionnaire included questions on respiratory symptoms and diseases, their comorbidities and several possible risk factors including smoking habits. Structured interviews and spirometry were performed in random samples of the responders to the 1992 and 2006 surveys, of which n=660 (in 1994) and n=623 (in 2009) were within identical age-spans (23-72 years). The trend in asthma prevalence was estimated by comparing the postal questionnaire surveys in 1996 and 2006, and the trend in COPD prevalence was estimated by comparing the samples participating in dynamic spirometry in 1994 and 2009, respectively. The prevalence of COPD was estimated based on two different definitions of COPD. Commonly used reference values for spirometry were evaluated based on randomly sampled healthy non-smokers defined in clinical examinations of participants in the 2006 postal questionnaire (n=501). The main focus of the evaluation was the global lung function initiative (GLI) reference values published in 2012, for which Z-scores and percent of predicted values were analysed. New sex-specific reference values for spirometry were estimated by linear regression, with age and height as predictors. These new OLIN reference values were also evaluated on a sample of healthy non-smokers identified in the population-based West Sweden Asthma Study. Results Although the prevalence of smoking decreased from 27.4% to 19.1%, p<0.001, between 1996 and 2006, the prevalence of physician-diagnosed asthma increased from 9.4% to 11.6%, p<0.001. The prevalence of symptoms common in asthma such as recurrent wheeze did not change significantly between the surveys or tended to decrease, while bronchitis symptoms such as cough and sputum production decreased significantly. The evaluation of the GLI reference values showed that the predicted values were significantly lower compared to the observed values in Norrbotten, which makes the percent of predicted too high. This was especially true for FVC percent predicted with a mean of 106%. In general, the deviations were more pronounced among women. New OLIN reference values valid for the Norrbotten sample were modelled and showed a high external validity when applied on the sample from western Sweden. The prevalence of moderate to severe COPD decreased substantially over the 15-year period between 1994 and 2009, regardless of definition. Conclusions In parallel with substantially decreased smoking habits in the population between 1996 and 2006, the prevalence of several airway symptoms decreased while the prevalence of physician-diagnosed asthma increased. These results suggest increased diagnostic activity for asthma, but may also suggest that the asthma prevalence has continued to increase. In contrast to asthma, the prevalence of COPD tended to decrease and moderate to severe COPD decreased substantially. The continuous decrease in smoking in Sweden during several decades prior to the study period is most likely contributing to these results. The evaluation of reference values showed that the GLI reference values were lower than the observed spirometric values in the population, especially for women, why the new up-to date reference values may be of importance for disease evaluation in epidemiology and in the health care as well.

Current treatment practice guidelines in a number of countries mandate the assessment of violence risk in all patients diagnosed with schizophrenia. Although more than 100 different instruments have been developed to facilitate the assessment of violence risk, few have been specifically validated for use in those with schizophrenia. Recent work instead suggests that these instruments are typically associated with lower predictive validity in samples with schizophrenia when compared to that achieved in diagnostically heterogeneous samples, leading to concerns that these instruments omit risk factors that may be specific to the prediction of violence risk in this population. The present thesis therefore aimed to investigate the predictive validity of a number of risk factors for violence in those with schizophrenia. Firstly, to identify key risk factors for violence, a meta-analysis was undertaken, finding that although a number of criminal history risk factors are strongly associated with violence risk, nonetheless a number of risk factors rarely assessed by existing violence risk assessment instruments were significantly associated with violence in those with schizophrenia; most notably a history of attempted suicide. Results of this review also suggested that although the criminal history domain is most strongly associated with violence risk, nonetheless, there is considerable variability in the magnitude of association for the individual risk factors. Study two therefore aimed to investigate this variability and found that a history of violence was most strongly associated with subsequent violence. Study three aimed to identify whether suicidal behaviour, which has rarely been considered risk factors for violence in previous work, incrementally contributes to the prediction of violence. A simple risk model composed of young age, comorbid substance use disorder, previous violence, and a history of suicidal threats, explained as much predictive validity, as measured by the area under the receiver operating characteristic curve, as established risk assessment instruments such as the HCR–20, LSI–R, PCL–R, and VRAG. Current risk assessment approaches may therefore need revision in light of these findings.

published_or_final_version / abstract / Dentistry / Master / Master of Dental Surgery

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences

published_or_final_version / abstract / Psychology / Master / Master of Philosophy

published_or_final_version / Journalism and Media Studies Centre / Doctoral / Doctor of Philosophy

Introduction Coronary artery disease (CAD) is the most common cause of death in Europe and North America and early detection of atherosclerosis is a clinical priority. Diagnosis of CAD remains conventional angiography, although recent technology has introduced non-invasive imaging of coronary arteries using computed tomographic coronary angiography (CTCA), which enables the detection and quantification of coronary artery calcification (CAC). CAC forms within the arterial wall and is usually found in or adjacent to atherosclerotic plaques and is consequently known as sub-clinical atherosclerosis.  The conventional cardiovascular (CV) risk factors used to quantify the estimated 10-year coronary event risk comprise dyslipidaemia, hypertension, diabetes mellitus, obesity, smoking and family history of CAD. Nevertheless, their relationship with significant (>50%) stenosis, their interaction with the CAC score and their predictive ability for CAC presence and extent has not been fully determined in symptomatic patients.   Methods   For Papers 1-4 we took patients from the Euro-CCAD cohort, an international study established in 2009 in Umeå, Sweden. The study data gave us the CAC score and the CV risk factor profile in 6309 patients, together with angiography results for a reduced cohort of 5515 patients. In Papers 1 and 2 we assessed the risk factors for significant stenosis, including CAC as a risk factor. Paper 2 carried out this analysis by geographical region: Europe vs USA and northern vs southern Europe. Paper 3 investigated the CV risk factors for CAC presence, stratified by age and gender, while Paper 4 assessed the CV risk factors for CAC extent, stratified by gender.  In paper 5 we carried out a systematic review and meta-analysis of all studies of the risk factor predictors of CAC presence, extent and progression in symptomatic patients. From a total of 884 studies, we identified 10 which fitted our inclusion criteria, providing us with a total of 15,769 symptomatic patients. All 10 were entered in the systematic review and 7 were also eligible for the meta-analysis.   Results Paper 1:           Among risk factors alone, the most powerful predictors of significant coronary stenosis were male gender followed by diabetes, smoking, hypercholesterolaemia, hypertension, family history of CAD and age; only obesity was not predictive. When including the log transformed CAC score as a risk factor, this proved the most powerful predictor of >50% stenosis, but hypercholesterolaemia and hypertension lost their predictive ability. The conventional risk factors alone were 70% accurate in predicting significant stenosis, the log transformed CAC score alone was 82% accurate but the combination was 84% accurate and improved both sensitivity and specificity.  Paper 2:           Despite some striking differences in profiles between Europe and the USA, the most important risk factors for >50% stenosis in both groups were male gender followed by diabetes. When the log CAC score was included as a risk factor, it became by far the most important predictor of >50% stenosis in both continents, followed by male gender. In the northern vs southern Europe comparison the result was similar, with the log CAC score being the most important predictor of >50% stenosis in both regions, followed by male gender.  Paper 3:           Independent predictors of CAC presence in males and females were age, dyslipidaemia, hypertension, diabetes and smoking, with the addition of family history of CAD in males; obesity was not predictive in either gender. The most important predictors of CAC presence in males were dyslipidaemia and diabetes, while among females the most important predictors of CAC presence were diabetes followed by smoking. When analysed by age groups, in both males and females aged <70 years, diabetes, hypertension and dyslipidaemia were predictive, with diabetes being the strongest; in females aged <70 years, smoking was also predictive. Among those aged ≥70 years, the results are completely different, with only dyslipidaemia being predictive in males but smoking and diabetes were predictive in females.  Paper 4:           In the total cohort, age, male gender, diabetes, obesity, family history of CAD and number of risk factors predicted an increasing CAC score, with the most important being male gender and diabetes. In males, hypertension and dyslipidaemia were also predictive, although diabetes was the most important predictor. Diabetes was similarly the most important risk factor in females, followed by age and number of risk factors. Among patients with CAC, hypertension, dyslipidaemia and diabetes predicted CAC extent in both males and females, with diabetes being the strongest predictor in males followed by dyslipidaemia, while diabetes was also the strongest predictor in females, followed by hypertension. Quantile regression confirmed the consistent predictive ability of diabetes.  Paper 5:           In the systematic review, age was strongly predictive of both CAC presence and extent but not of CAC progression. The results for CAC presence were overwhelmed by data from one study of almost 10,000 patients, which found that white ethnicity, diabetes, hypertension and obesity were predictive of CAC presence but not male gender, dyslipidaemia, family history or smoking. With respect to CAC extent, only male gender and hypertension were clearly predictive, while in the one study of CAC progression, only diabetes and hypertension were predictive. In the meta-analysis, hypertension followed by male gender, diabetes and age were predictive of CAC presence, while for CAC extent mild-moderate CAC was predicted by hypertension alone, whereas severe CAC was predicted by hypertension followed by diabetes.   Conclusion Our investigation of the Euro-CCAD cohort showed that the CAC score is far more predictive of significant stenosis than risk factors alone, followed by male gender and diabetes, and there was little benefit to risk factor assessment over and above the CAC score for >50% stenosis prediction. Regional variations made little difference to this result. Independent predictors of CAC presence were dyslipidaemia and diabetes in males and diabetes followed by smoking in females. The risk factor predictors alter at age 70. The most important risk factor predictors of CAC extent were male gender and diabetes; when analysed by gender, diabetes was the most important in both males and females. Our studies have consistently shown the strong predictive ability of male gender in the total cohort and diabetes in males and females and this is reflected in the meta-analysis, which also found hypertension to be independently predictive. Interestingly, dyslipidaemia does not appear to be a strong risk factor.