Epidemiological Study Of Risk Factors Research Articles

Epidemiologic study of the risk factors of the adult female urinary incontinence in Uygur of Kashi in Xinjiang

To evaluate the prevalence and associated risk factors of stress urinary incontinence(SUI) in adult women in Xinjiang. In the cross-sectional study, 3403 Uygur women aged over 20 years were interviewed through a questionnaire of International Consultation on Incontinence Questionnaire Female Lower Urinary Tract Symptoms Module (ICIQ-FLUTS) and the adult questionnaire were used in our research. All parts of the content were according to the characteristics of women in Xinjiang and the purpose of our research. The risk factors were studied by Logistic regression analysis. The prevalence of urinary incontinence(UI) was 41.96% (1428/3403) and 28.21% (960/3403) of SUI in Uygur women. In multivariate logistic regression analysis, the risk factors of SUI are body mass index (OR = 1.672, 95%CI:1.082-2.584), parity (OR = 5.092, 95%CI:3.889-6.666), neonatal birth weight (OR = 5.623, 95%CI:3.335-9.480), the mode of delivery (OR = 2.247, 95%CI:1.634-3.090), the lateral episiotomy (OR = 4.448, 95%CI:3.112-6.357), menopause(OR = 5.145, 95%CI: 3.613-7.328), chronic pelvic pain (OR = 3.869, 95%CI:1.051-14.250), pelvic organ prolapse (OR = 3.501, 95%CI:2.508-4.887). The incidence of SUI is related with multiple factors, especially with obesity and the obstetric factor.

Computer-aided Assessment of Regional Abdominal Fat with Food Residue Removal in CT

Separate quantification of abdominal subcutaneous and visceral fat regions is essential to understand the role of regional adiposity as risk factor in epidemiological studies. Fat quantification is often based on computed tomography (CT) because fat density is distinct from other tissue densities in the abdomen. However, the presence of intestinal food residues with densities similar to fat may reduce fat quantification accuracy. We introduce an abdominal fat quantification method in CT with interest in food residue removal. Total fat was identified in the feature space of Hounsfield units and divided into subcutaneous and visceral components using model-based segmentation. Regions of food residues were identified and removed from visceral fat using a machine learning method integrating intensity, texture, and spatial information. Cost-weighting and bagging techniques were investigated to address class imbalance. We validated our automated food residue removal technique against semimanual quantifications. Our feature selection experiments indicated that joint intensity and texture features produce the highest classification accuracy at 95%. We explored generalization capability using k-fold cross-validation and receiver operating characteristic (ROC) analysis with variable k. Losses in accuracy and area under ROC curve between maximum and minimum k were limited to 0.1% and 0.3%. We validated tissue segmentation against reference semimanual delineations. The Dice similarity scores were as high as 93.1 for subcutaneous fat and 85.6 for visceral fat. Computer-aided regional abdominal fat quantification is a reliable computational tool for large-scale epidemiological studies. Our proposed intestinal food residue reduction scheme is an original contribution of this work. Validation experiments indicate very good accuracy and generalization capability.

Editorial introductions

Editorial introductions

Introduction to the principles of using a W shoe on foundered feet

The aim of this article is to review current knowledge of kinetic variables of the hoof-track interaction and track properties relevant to the objective of minimizing injuries to horses at racing tracks. In each phase of the stance—primary impact, secondary impact, support, and breakover, the hoof experiences different combinations of force and acceleration. The role of each combination, and of measured track properties, in causing catastrophic and chronic injuries to the limbs of racing horses is unknown. Limited data of this type have been provided in previous epidemiologic studies of risk factors for breakdown. Future epidemiological studies should include characterization of the track surfaces and a more complete description of the kinematics of the hoof and surface. Consideration of an appropriate range of physical properties is necessary in track design, testing, and maintenance.

Proportional mean residual life model for right-censored length-biased data

To study disease association with risk factors in epidemiologic studies, cross-sectional sampling is often more focused and less costly for recruiting study subjects who have already experienced initiating events. For time-to-event outcome, however, such a sampling strategy may be length biased. Coupled with censoring, analysis of length-biased data can be quite challenging, due to induced informative censoring in which the survival time and censoring time are correlated through a common backward recurrence time. We propose to use the proportional mean residual life model of Oakes & Dasu (Biometrika77, 409-10, 1990) for analysis of censored length-biased survival data. Several nonstandard data structures, including censoring of onset time and cross-sectional data without follow-up, can also be handled by the proposed methodology.

An epidemiologic study of mitochondrial membrane transporter protein gene polymorphism and risk factors for neural tube defects in Shanxi, China.

The present study involved a questionnaire survey of 156 mothers that gave birth to children with neural tube defects or had a history of pregnancy resulting in children with neural tube defects (case group) and 156 control mothers with concurrent healthy children (control group) as well as detection of mitochondrial membrane transporter protein gene [uncoupling protein 2 (UCP2)] polymorphism. The maternal UCP2 3’ untranslated region (UTR) D/D genotype and D allele frequency were significantly higher in the case group compared with the control group (odds ratio (OR) 3.233; 95% confidence interval (CI) 1.103–9.476; P = 0.040; OR: 3.484; 95% CI: for neural tube defects 2.109–5.753; P < 0.001). Univariate and multivariate logistic regression analysis of risk factors for neural tube defects showed that a maternal UCP2 3’ UTR D/D genotype was negatively interacted with the mothers’ consumption of frequent fresh fruit and vegetables (S = 0.007), positively interacted with the mothers’ frequency of germinated potato consumption (S = 2.15) and positively interacted with the mothers’ body mass index (S = 3.50). These findings suggest that maternal UCP2 3’ UTR gene polymorphism, pregnancy time, consumption of germinated potatoes and body mass index are associated with an increased risk for neural tube defects in children from mothers living in Shanxi province, China. Moreover, there is an apparent gene-environment interaction involved in the development of neural tube defects in offspring.

Really small vascular disease of the brain

The diagnosis of cerebrovascular disease has changed dramatically over the past several decades with the introduction of CT and MRI. These technologies have made it apparent that “silent” cerebral infarction (i.e., without an associated history of TIA or stroke) is more prevalent than clinically symptomatic infarction. Between 8% and 20% of people 50–75 years of age have such findings.1 In the Cardiovascular Health Study (CHS), an ongoing epidemiologic study of cardiovascular risk factors in the elderly, 28% of seniors, average age 75 years, had “silent” infarcts on MRI scanning,2 and ∼18% of those without baseline silent strokes on MRI had new “silent” infarcts on a 5-year follow-up MRI.3 Several studies have shown that these “silent” infarcts are not benign. In the Rotterdam study, a longitudinal study of 1,000 healthy elderly between ages 60 and 90 years who were followed for 4 years, participants with baseline “silent” infarcts (≥3 mm) had more rapid cognitive decline than those without infarcts, with twice the risk of incident dementia.4 In the CHS study, approximately 87% of silent infarcts on follow-up MRI were 3–20 mm, of which 20% were ≤5 mm. This subgroup demonstrated higher levels of …

Effect of dietary and lifestyle factors on the risk of gestational diabetes: review of epidemiologic evidence

Gestational diabetes mellitus (GDM), defined as glucose intolerance with onset or first recognition in pregnancy, is a common pregnancy complication and a growing health concern. GDM has been related to significant short-term and long-term adverse health outcomes for both mothers and offspring. Importantly, this number is increasing with the increasing burden of obesity among women of reproductive age. Collectively, these data highlight the significance of understanding risk factors, in particular modifiable factors, for GDM and of preventing GDM among high-risk populations. Research in the past decade has identified a few diet and lifestyle factors that are associated with GDM risk. This review provides an overview of emerging diet and lifestyle factors that may contribute to the prevention of GDM. It also discusses major methodologic concerns about the available epidemiologic studies of GDM risk factors.

Contribution of violaxanthin, neoxanthin, phytoene and phytofluene to total carotenoid intake: Assessment in Luxembourg

Dietary carotenoid intake has been associated with a low incidence of several chronic diseases, including cardiovascular complications, cancer, and macular degeneration. While food composition and intake of some carotenoids such as β-carotene and lycopene is frequently available, information on the contribution of less studied epoxycarotenoids such as neoxanthin, violaxanthin, and phytoene/phytofluene, is scant. The present study describes the assessment of ten individual carotenoids in frequently consumed food items and estimates their contribution to total carotenoid intake in Luxembourg. For this purpose, 50 frequently consumed food items were collected from local groceries, and combined with food consumption data obtained from the first epidemiological Luxembourgish cardio-vascular risk factor study (ORISCAV-LUX). Highest epoxycarotenoid content was found in bell peppers (4.5mg/100g), highest amount of phytoene/phytofluene in apricot (9.6mg/100g) and tomato ketchup (4.5mg/100g). National daily per capita intake was assessed as 7.6mg α- and β-carotene, 2.0mg phytoene, 1.8mg lycopene, 1.5mg lutein, 1.4mg β-cryptoxanthin, 1.2mg violaxanthin, 0.7mg phytoene, 0.5mg neoxanthin, and 0.3mg zeaxanthin, with 10% of total daily carotenoid intake from epoxycarotenoids and 16% from phytoene/phytofluene. While intake in Luxembourg appears to be comparable to other European data, this study highlights the importance of taking less frequently analysed carotenoids into account for determining total intake.

The application of epidemiology in aquatic animal health -opportunities and challenges.

Over recent years the growth in aquaculture, accompanied by the emergence of new and transboundary diseases, has stimulated epidemiological studies of aquatic animal diseases. Great potential exists for both observational and theoretical approaches to investigate the processes driving emergence but, to date, compared to terrestrial systems, relatively few studies exist in aquatic animals. Research using risk methods has assessed routes of introduction of aquatic animal pathogens to facilitate safe trade (e.g. import risk analyses) and support biosecurity. Epidemiological studies of risk factors for disease in aquaculture (most notably Atlantic salmon farming) have effectively supported control measures. Methods developed for terrestrial livestock diseases (e.g. risk-based surveillance) could improve the capacity of aquatic animal surveillance systems to detect disease incursions and emergence. The study of disease in wild populations presents many challenges and the judicious use of theoretical models offers some solutions. Models, parameterised from observational studies of host pathogen interactions, have been used to extrapolate estimates of impacts on the individual to the population level. These have proved effective in estimating the likely impact of parasite infections on wild salmonid populations in Switzerland and Canada (where the importance of farmed salmon as a reservoir of infection was investigated). A lack of data is often the key constraint in the application of new approaches to surveillance and modelling. The need for epidemiological approaches to protect aquatic animal health will inevitably increase in the face of the combined challenges of climate change, increasing anthropogenic pressures, limited water sources and the growth in aquaculture.Table of contents1 Introduction 42 The development of aquatic epidemiology 73 Transboundary and emerging diseases 93.1 Import risk analysis (IRA) 103.2 Aquaculture and disease emergence 113.3 Climate change and disease emergence 133.4 Outbreak investigations 134 Surveillance and surveys 154.1 Investigation of disease prevalence 154.2 Developments in surveillance methodology 164.2.1 Risk-based surveillance and scenario tree modelling 164.2.2 Spatial and temporal analysis 164.3 Test validation 175 Spread, establishment and impact of pathogens 185.1 Identifying routes of spread 185.1.1 Ex-ante studies of disease spread 195.1.2 Ex-post observational studies 215.2 Identifying risk factors for disease establishment 235.3 Assessing impact at the population level 245.3.1 Recording mortality 245.3.2 Farm health and production records 265.3.3 Assessing the impact of disease in wild populations 276 Conclusions 317 Competing interests 328 Authors' contributions 329 Acknowledgements 3310 References 33

Epidemiological risk factor study concerning abnormal attitudes toward eating and adverse dieting behaviours among 12‐ to 25‐years‐old Chinese students

Most epidemiological studies of eating disorders have been carried out in North America and Western Europe. There are few exploratory studies in China on the prevalence of eating disorders and influential factors that cause eating disorders. A survey of school and college students aged between 12 and 25 in two cities in China had 1199 participants (95.8% response rate), 767 were female (63.9%) and 432 male (36.1%) Subjects completed questionnaires including the Eating Attitude Test (EAT-26). 9.9% of the females and 2.0% of the males showed high risk scores (EAT ≥ 20) regardless of whether their weight was normal or they were underweight. Such high risk groups showed a significantly higher degree of psychological characteristics relevant to eating disorders in both female and male subjects. Both Chinese females and a group of Chinese males may be at high risk for eating disorders.

Epidemiological study of pasture-associated laminitis and concurrent risk factors in the South of England

A retrospective study of laminitis was carried out to identify risk factors associated with this disease on an East Anglian farm with approximately 1000 animals living in an area of...

Comments on: Epidemiological study of urge urinary incontinence and risk factors in China

Dear Editor,Zhu and colleagues investigated urge urinary incontinence(UUI) and risk factors in China via a cross-sectional studyinvolving 20,000 adult Chinese women [1]. This cross-province survey is intriguing in that the authors provide uswith a general profile of UUI among the general populationin China. However, we are concerned about their interpre-tation of their findings.As many potential risks factors were not evaluated in thestudy, the conclusion that age is a major independent riskfactor of UUI as draw in the article would raise concerns.The diagnosis of UUI is mainly based on clinicalsymptoms. Thus UUI can be viewed as a clinical syndrome.A variety of diseases may present symptoms like UUI, andmany risk factors may contribute to the prevalence of UUI[2]. Limited by the methodological pitfall, this study failedto determine the causal relationships between UUI and riskfactors. We agree that UUI should not be accepted as anatural consequence of aging and being untreatable.Therefore, patients with UUI, especially those who haveatypical features or severe symptoms, should appeal tospecialist and undergo full assessment with cystoscopy andurodynamic study if necessary [2].In their study, severity assessment such as informationabout incontinence episode frequency was not reported.Although limited by the relatively sample size, it would beinteresting if there is a positive correlation between UUIseverity and age, which might support age as a major riskfactor indirectly.Besides the common risk factors of UUI like gyneco-logical diseases, urological disorders, as well as neurolog-ical disorders, such as cerebrovascular diseases mightaccount for the causes of UUI. In the light of thisconsideration, urological symptoms such as urodynia,hematuria, or neurological symptoms which may point toa neuropathic bladder as the cause of UUI (e.g., new onsetweakness, paraesthesia, back pain, visual disturbances) areof great value to clarify the etiology of UUI [3].In addition, since it is a cross-province survey, we wouldlike to know whether there is difference in the prevalence ofUUI among provinces, as well as between rural and urbanareas.

The AlzRisk database: Web-based catalogue and meta-analysis of findings from epidemiologic studies of non-genetic risk factors for Alzheimer's disease

The AlzRisk database: Web-based catalogue and meta-analysis of findings from epidemiologic studies of non-genetic risk factors for Alzheimer's disease

Cox regression model with time-varying coefficients in nested case-control studies

The nested case-control (NCC) design is a cost-effective sampling method to study the relationship between a disease and its risk factors in epidemiologic studies. NCC data are commonly analyzed using Thomas' partial likelihood approach under Cox's proportional hazards model with constant covariate effects. Here, we are interested in studying the potential time-varying effects of covariates in NCC studies and propose an estimation approach based on a kernel-weighted Thomas' partial likelihood. We establish asymptotic properties of the proposed estimator, propose a numerical approach to construct simultaneous confidence bands for time-varying coefficients, and develop a hypothesis testing procedure to detect time-varying coefficients. The proposed inference procedure is evaluated in simulations and applied to an NCC study of breast cancer in the New York University Women's Health Study.

FC30 An epidemiologic study of prevalent risk factors of basal cell carcinoma in the Greek population

Introduction The risk for BCC development results from the interplay of both constitutional and environmental factors, with ultraviolet radiation (UVR) being the primary established risk factor in the development of BCC [1,2]. The epidemiologic risk factors of BCC in Mediterranean populations remain unclear. Aim To investigate the risk associations of BCC in the Greek population. Methods We conducted a hospital-based case-control study. We studied 199 patients with histologically confirmed BCC and 200 cancer-free controls. The following data were collected by the use of a standardized questionnaire: pigmentary traits (tanning ability, ease of sunburning), patterns of sun exposure (continuous versus intermittent), timing of sun exposure, history of severe sunburns, use of sunscreens, exposure to artificial sources of UVR, personal or family history of skin cancer, and lifestyle-related factors (smoking). A clinical examination was performed with respect to pigmentary traits (skin/hair/eye color), number of melanocytic nevi, actinic keratoses, lentigines, and the presence of elastosis. Results In our multivariate analysis of BCC, several factors were found to be significantly associated with BCC (P<0.05), including female sex, light skin color, number of years of occupational sun exposure, number of sunburns during adulthood, no use of sunscreen, and presence of nevi and lentigines. A trend for a ‘dose-response’ effect was noted for patients who had 5 years or more, of occupational sun exposure. No association was found with skin type, exposure to non-solar UVR exposure, and lifestyle-related factors (smoking, alcohol consumption). Statistically significant risk factors for early BCC (age at diagnosis <50 years) included female sex, number of weeks per year spent at the beach before the age of 20, and the number of sunburns during childhood. Conclusion BCC risk was associated with light skin color, occupational sun exposure, and the presence of nevi and lentigines. The association of early onset BCC with recreational sun exposure and sunburns during childhood and adolescence suggests that intense intermittent sun exposure during the early years of life may be a key risk factor for development of BCC at an early age.

Epidemiological study of urge urinary incontinence and risk factors in China

To evaluate the prevalence and risk factors of urge urinary incontinence (UUI) in Chinese adult women. A cross-sectional study using the multistaged random sampling method. Twenty thousand Chinese women aged >or=20 years were interviewed. Of the women aged 20-99 years, the prevalence of UUI was 2.6%, which increased with age. Age, waist circumstance, constipation, chronic pelvic pain, history of gynecological diseases, and menopausal status were independent risk factors of UUI. Women aged 60 or above were 2.329 times more likely to suffer UUI as compared to women aged 20-40. Women in perimenopausal or postmenopausal status were, respectively, 1.766 or 2.285 times more likely to suffer UUI as compared to women in normal menstruation. However, parity and mode of delivery were not risk factors. The prevalence of UUI is 2.6% among Chinese adult women. Age is a major independent risk factor of UUI.

Epidemiological study of risk factors for esophageal cancer in Yangquan Area of Shanxi Province based on discordant sib pairs

AIM: To explore the main environmental riskfactors for esophageal squamous cell carcinoma (ESCC) based on discordant sib pairs (DSPs) in a moderately high-incidence area, Yangquan City, Shanxi Province, and to provide theoretical evidence for developing effective control and prevention measures in this area. METHODS: A 1∶1 matched case-control study was carried out. One hundred and twenty-seven DSPs were recruited from the cancer registration and follow-up system of the local hospital. All ESCC cases and their matched unaffected sibs were subjected to a survey to obtain demographic information along with personal and family history, and lifestyle factors. The McNemar test was used for data analysis. RESULTS: Compared with matched unaffected sibs, low family income (OR = 2.00, 95%CI: 1.14-3.52, P = 0.0143), hot food eating and drinking (OR = 2.56, 95%CI: 1.44-4.57, P = 0.0009) and heavy drinking (P = 0.0027) were risk factors for ESCC in the area. These factors play important roles in the development of ESCC, even in cases with a family history of ESCC, and the odds ratios (95%CI) were 2.18 (1.07-4.45), 5.00(1.91-13.06) and infi nity, respectively. CONCLUSION: Besides genetic factors, lack of nutrition, hot food eating and heavy drinking are main risk factors for ESCC in Yangquan City. Prevention and control of ESCC should be intervened at multiple levels, such as genetic factors and lifestyles.

PrP genotype: A flock-level risk factor for scrapie?

Previous epidemiological studies of risk factors for classical scrapie at flock level have identified a variety of management and purchase related variables, along with increased flock size and, in some cases, breed effects. Although known as a risk factor at the individual animal level, PrP genotype frequencies at flock level have not yet been studied. In an unmatched case–control study, three measures of flock-level prion protein (PrP) frequency estimates were investigated with respect to the scrapie status of the flock in 293 British sheep flocks (195 control flocks and 98 case flocks). Flocks with positive frequencies (more than 0 per cent) of two genotypes (VRQ/VRQ and AHQ/VRQ), large frequencies (more than 10 per cent) of the ARR/VRQ genotype, and large frequencies (more than 5.2 per cent) of the VRQ allele were at increased odds of being affected with clinical classical scrapie. When adjusted for flock size, breed and sampling strategy the genotype and allele effects remained, except that for flocks with positive frequencies of VRQ/VRQ. The known effect of increased risk with increased flock size was confirmed. A measure of the flock PrP genotype frequency profile should thus be included in studies of risk factors for scrapie. It could also be integrated into risk-based surveillance strategies for identification of “at-risk-of scrapie” flocks.

Invited Commentary: Genes, Environment, and Hybrid Vigor

In the 1950s, case-control studies of smoking and lung cancer established a paradigm for epidemiologic studies of risk factors for chronic diseases. Since then, thousands of case-control studies have examined possible associations of countless risk factors with numerous diseases, rarely finding associations as strong or consistent as that of smoking with lung cancer. Recently, researchers have applied advances in molecular genetics to conduct candidate gene and genome-wide association studies of lung cancer. Skeptics among both epidemiologists and geneticists have argued that genomic research adds little value when most cases of disease can be attributed to a preventable exposure; however, well-conducted studies of gene-environment interactions that draw on data from more than 50 years of research in toxicology, pathophysiology, and behavioral science offer important models for the development of more comprehensive approaches to understanding the etiology of chronic diseases.