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Epidemiological Factors (epidemiological + factor)
Selected AbstractsClinical dental examinations of 357 donkeys in the UK.EQUINE VETERINARY JOURNAL, Issue 4 2009Part 2: Epidemiological studies on the potential relationships between different dental disorders, between dental disease, systemic disorders Summary Reasons for performing study: Dental disease has been shown to be a risk factor for weight loss and colic in horses. No extensive clinical studies in donkeys have investigated the potential relationship between different dental disorders, or between dental disease and systemic disorders. Objectives: To determine possible associations between dental disease and body condition score, weight loss, the need for supplemental feeding and prevalence of colic in donkeys of all ages, and to gain a better understanding of the pathogenesis of dental disease by the determination of associations between different dental disorders. Methods: A prospective cross-sectional analysis of clinical dental examinations of 357 donkeys in The Donkey Sanctuary, Sidmouth was performed. Other epidemiological factors such as estimated age group, body condition score, weight loss, medical history and supplemental feeding were also recorded, and multiple regression analyses were performed to determine possible associations. Results: Donkeys from older age groups were more likely to have dental disease, poor body condition score and suffered previous colic episodes. The presence of dental disease was also significantly associated with weight loss, colic, low body condition score and the need for supplemental feeding. The presence of diastemata, periodontal disease, wave mouth, smooth mouth and step mouth are frequently associated with the presence of other dental disorders. Conclusions: In addition to oral-related pain, dental disease can cause significant systemic disorders and so has increased welfare implications in donkeys. Some dental disorders promote the development of other types of dental abnormalities and thus increase the severity of dental disease in individual animals. Potential significance: Effective treatment of dental disorders slows down the progression of dental disease and decreases the risk of developing some medical disorders such as colic and weight loss that are associated with dental disease. [source] Dynamic versus static models in cost-effectiveness analyses of anti-viral drug therapy to mitigate an influenza pandemicHEALTH ECONOMICS, Issue 5 2010Anna K. Lugnér Abstract Conventional (static) models used in health economics implicitly assume that the probability of disease exposure is constant over time and unaffected by interventions. For transmissible infectious diseases this is not realistic and another class of models is required, so-called dynamic models. This study aims to examine the differences between one dynamic and one static model, estimating the effects of therapeutic treatment with antiviral (AV) drugs during an influenza pandemic in the Netherlands. Specifically, we focus on the sensitivity of the cost-effectiveness ratios to model choice, to the assumed drug coverage, and to the value of several epidemiological factors. Therapeutic use of AV-drugs is cost-effective compared with non-intervention, irrespective of which model approach is chosen. The findings further show that: (1) the cost-effectiveness ratio according to the static model is insensitive to the size of a pandemic, whereas the ratio according to the dynamic model increases with the size of a pandemic; (2) according to the dynamic model, the cost per infection and the life-years gained per treatment are not constant but depend on the proportion of cases that are treated; and (3) the age-specific clinical attack rates affect the sensitivity of cost-effectiveness ratio to model choice. Copyright © 2009 John Wiley & Sons, Ltd. [source] Hepatocellular carcinoma occurring in nonfibrotic liver: Epidemiologic and histopathologic analysis of 80 French casesHEPATOLOGY, Issue 2 2000Marie-Pierre Bralet M.D., Ph.D. Hepatocellular carcinoma (HCC) occurring in nonfibrotic liver represents a rare, ill-defined subgroup of HCC without cirrhosis in which mechanisms of hepatocarcinogenesis remain unclear. The aim of our study was to assess epidemiological factors and detailed histopathologic changes in the nontumoral liver of patients developing such tumors. Of 330 HCCs resected in our institution between 1985 and 1998, we retrospectively analyzed 80 cases (53 men, 27 women; mean age, 51 ± 16 years) in which the nontumoral liver showed no (n = 28) or minimal (n = 52) portal fibrosis without any septal fibrosis. In the group with no portal fibrosis there was no male predominance, and patients were significantly younger (44 ± 19 years vs. 54 ± 14 years) than those with minimal portal fibrosis. Sixty-seven tumors were typical HCCs, 8 were of fibrolamellar type, and 5 were hepatocholangiocarcinomas. Mean tumor size was 10 ± 5 cm. Risk factors for HCC development were found in 30 patients: hepatitis B (n = 17) or C (n = 2) virus infections, alcohol consumption (n = 11), and hemochromatosis (n = 1). In the nontumoral liver, periportal and lobular necrosis, mild portal inflammation, steatosis, and iron overload were present in 15%, 57%, 52%, and 54% of cases, respectively. Liver cell changes were noted in 6%. This study emphasizes the need for strict criteria to classify HCC without cirrhosis. HCC in nonfibrotic liver is a distinct subgroup in which nontumoral liver shows nonspecific minimal changes without regeneration or premalignant lesion. Etiologic factors are often unidentified, although presence of HBV infection in 21% suggests a direct oncogenic role of this virus. [source] Influence of epidemiological factors on blood transfusionISBT SCIENCE SERIES: THE INTERNATIONAL JOURNAL OF INTRACELLULAR TRANSPORT, Issue 1 2007S. Laperche The prevalence, incidence and risk factors of infectious diseases observed in the general population have been described to directly influence transfusion medicine, especially the blood selection. The objective is to ensure the blood safety. The characterization of modes of transmission influences the donor selection: the risk factors of the main blood-borne infections have permitted to adapt the pre-donation questionnaire in order to exclude at-risk donors. The prevalence of infections also has an impact on the blood screening strategy. For example, anti-HBc antibody (Ab) screening is currently performed only in countries where the HBV prevalence is compatible with a reasonable number of donor exclusions. HTLV Ab screening is implemented in countries in which the rate of donors originating from endemic areas could represent a risk for blood components. Measurement of incidence which contributes to the residual risk has led to the introduction of nucleic acid testing (NAT) for HIV, HCV and in some cases for HBV in viral screening strategy in many countries worldwide. The observed NAT yield differs according to the incidence of the infection and according to the country. Finally, the putative blood transmission of new and emerging pathogens has led to implement specific and non-specific measures in order to enhance blood safety. Conversely, although the blood donor population is selected, the data observed in this population have also contributed to better understand epidemiology and pathogenesis of infection. Moreover, owing to the recent progress in developing modelling approaches for estimating risk, we are able to anticipate a transfusion transmission threat by introducing, when necessary, specific measures intended for reduce this risk. [source] Ethnic variation, epidemiological factors and quality of life impairment associated with dyspepsia in urban MalaysiaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2010S. MAHADEVA Aliment Pharmacol Ther,31, 1141,1151 Summary Background, The role of ethnicity in the development of dyspepsia remains uncertain. Aims, To examine the epidemiology of dyspepsia in a multi-ethnic Asian population and its impact on health-related quality of life (HRQOL). Methods, A cross-sectional survey was conducted in a representative urban population in Kuala Lumpur, Malaysia. Results, A total of 2039 adults (mean ± s.d. age: 40.5 ± 11.8 years, males 44.2%, ethnicity: Malays 45.3%, Chinese 38.0% and Indians 13.1%, tertiary education level 62%, professional employment 47.7% and median monthly income USD 850.00) were interviewed. Dyspepsia was prevalent in 496 (24.3%) adults. Independent predictors for dyspepsia, explored by logistic regression, were identified as: Malay (OR 2.17, 95% CI = 1.57,2.99) and Indian (OR 1.59, 95% CI = 1.03,2.45) ethnicity, heavy chilli intake (OR 2.35, 95% CI = 1.15,4.80), use of regular analgesia (OR 3.51, 95% CI = 2.54,4.87) and chronic illness (OR 1.67, 95% CI = 1.22,2.28). HRQOL was assessed with the EQ-5D and significantly lower scores were noted in dyspeptics compared with healthy controls (0.85 ± 0.17 vs. 0.95 ± 0.12, P < 0.0001). Conclusion, Ethnicity, in addition to recognized epidemiological factors, is a risk factor for dyspepsia in an urban multi-racial Asian population. [source] Clinical Features and Epidemiology of Tick Typhus in TravelersJOURNAL OF TRAVEL MEDICINE, Issue 2 2001Tomas Jelinek Background: Epidemiologic features of tick typhus among German travelers has not been surveyed recently. Methods: Clinical features, travel and medical histories in 78 patients with tick typhus who presented to a German outpatient clinic for Infectious and Tropical Diseases were investigated, in order to identify common epidemiological factors and potential strategies of prevention. Diagnosis was confirmed by serological detection of IgG- and IgM-antibodies to Rickettsia conorii by indirect immunofluorescence. Results: The majority of patients (71.8%) had visited southern Africa prior to presentation. All patients presented with fever as the main symptom. An eschar was still present in 68 patients (87.2%) with regional lymphadenitis in 19.2%. However, only a minority of patients (17.9%) remembered a tick bite at the location of the eschar. Conclusion: Efforts to reduce the incidence of tick typhus in travelers should focus on preventive measures targeting behavioral changes. Avoiding tick bites during travel to endemic areas appears to be the single most important prophylactic action. Taking this into consideration, it should be possible to decrease the number of travelers returning with tick typhus significantly by adequate pretravel counseling. [source] Recurrent Respiratory Papillomatosis: A Longitudinal Study Comparing Severity Associated With Human Papilloma Viral Types 6 and 11 and Other Risk Factors in a Large Pediatric Population,THE LARYNGOSCOPE, Issue S104 2004Brian J. Wiatrak MD Abstract Objectives/Hypothesis: A database was developed for prospective, longitudinal study of recurrent respiratory papillomatosis (RRP) in a large population of pediatric patients. Data recorded for each patient included epidemiological factors, human papilloma virus (HPV) type, clinical course, staged severity of disease at each surgical intervention, and frequency of surgical intervention. The study hypothesizes that patients with HPV type 11 (HPV-11) and patients younger than 3 years of age at diagnosis are at risk for more aggressive and extensive disease. Study Design: The 10-year prospective epidemiological study used disease staging for each patient with an original scoring system. Severity scores were updated at each surgical procedure. Methods: Parents of children with RRP referred to the authors' hospital completed a detailed epidemiological questionnaire at the initial visit or at the first return visit after the study began. At the first endoscopic debridement after study enrollment, tissue was obtained and submitted for HPV typing using polymerase chain reaction techniques and in situ hybridization. Staging of disease severity was performed in real time at each endoscopic procedure using an RRP scoring system developed by one of the authors (B.J.W.). The frequency of endoscopic operative debridement was recorded for each patient. Information in the database was analyzed to identify statistically significant relationships between extent of disease and/or HPV type, patient age at diagnosis, and selected epidemiological factors. Results: The study may represent the first longitudinal prospective analysis of a large pediatric RRP population. Fifty-eight of the 73 patients in the study underwent HPV typing. Patients infected with HPV-11 were significantly more likely to have higher severity scores, require more frequent surgical intervention, and require adjuvant therapy to control disease progression. In addition, patients with HPV-11 RRP were significantly more likely to develop tracheal disease, to require tracheotomy, and to develop pulmonary disease. Patients receiving a diagnosis of RRP before 3 years of age had significantly higher severity scores, higher frequencies of surgical intervention, and greater likelihood of requiring adjuvant medical therapy. Patients with Medicaid insurance had significantly higher severity scores and required more frequent surgical debridement. Birth by cesarean section appeared to be a significant risk factor for more severe disease and necessity of more frequent surgical intervention. Conclusion: Statistical analysis of the relationships among epidemiological factors, HPV type, and clinical course revealed that patients with HPV-11 and patients younger than 3 years of age at RRP diagnosis are prone to develop more aggressive disease as represented by higher severity scores at endoscopic debridement, more frequent operative debridement procedures per year, a greater requirement for adjuvant therapy, and greater likelihood of tracheal disease with tracheotomy. [source] Multiple senile lentigos of the face, a skin ageing pattern resulting from a life excess of intermittent sun exposure in dark-skinned caucasians: a case,control studyBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2006S. Monestier Summary Background, Different patterns of skin ageing can be described depending on the predominant lesions, i.e. wrinkles, laxity, atrophy, senile lentigos (SLs), etc. They may correspond to different epidemiological contexts. Objectives, To identify and assess the epidemiological factors for a skin ageing pattern characterized by a high density of SLs on the face, or ,lentigo ageing pattern' (LAP). Methods, An age- and sex-matched case,control study was conducted in individuals aged between 60 and 80 years, comparing cases (n = 118) with a very high number of SLs on the face for their age, and controls (n = 118) with no or very few SLs for their age. The cases and controls were recruited in two hospitals. Results, In univariate and multivariate analysis, LAP was associated with skin types III and IV, with frequent sunburns, and with the part of the lifetime cumulative sun exposure which was received during vacations. Conversely, there was no link with the occupational and everyday exposures and the total cumulative exposure. LAP was associated with multiple solar lentigos of the upper back. No relationship was found with postmenopausal hormonal therapy, number of naevi, or freckles. Conclusions, Different epidemiological factors may account for the different skin ageing patterns. LAP seems to develop preferentially in dark-skinned caucasians who have repeatedly received intermittent and intense sun irradiations throughout their life, and have often developed solar lentigos on the upper back earlier in life, whereas the ,prominent wrinkling' pattern is known to affect light-skinned people and smokers with a life excess of continuous exposure. [source] | ||||||||||