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1.
OBJECTIVES: To assess the risk of total and cardiovascular mortality in older adults with systolic hypertension and with a low ankle-arm index (AAI) as a marker of subclinical peripheral arterial disease (PAD). DESIGN: Prospective observational study PARTICIPANTS: A subgroup of 1537 participants in the Systolic Hypertension in the Elderly Program (SHEP) were screened for lower extremity arterial disease using the AAI. Participants were evaluated at 4 years to determine vital status and cause of death. Total and cardiovascular disease (CVD) mortality rates were assessed in relationship to clinical CVD at baseline, cardiovascular risk factors and the presence of a low AAI (subclinical PAD). RESULTS: Total mortality rates increased as the AAI decreased in those with and without clinical CVD at baseline. In those without clinical CVD at baseline, the presence of an AAI < or = .9 was associated with an age-adjusted relative risk (RR) of 3.00 for total mortality in men and 2.67 in women. Results were similar for CVD mortality and persisted after adjustment for cardiovascular risk factors including the presence of an abnormal electrocardiogram. CONCLUSIONS: A low ankle arm-index predicted a two to three-fold increase in total and cardiovascular mortality in older adults with systolic hypertension of risk for incident cardiovascular disease. In this study of older adults with systolic hypertension, 19.7% of the participants had subclinical PAD. Risk factor modification could be targeted to older adults based on markers of asymptomatic atherosclerosis.  相似文献   

2.
A study was done to find and quantify risk factors for coccidiosis. The study population consisted of 4774 broiler flocks kept on 177 farms. Flocks were considered a case when at least one bird in the flock showed microscopic presence of oocysts in intestinal scrapings in a grow-out cycle. Other flocks were defined as controls. This was done for three types of Eimeria: Eimeria acervulina, Eimeria tenella and Eimeria maxima. Logistic regression was used to assess variables that influence the occurrence of Eimeria species. There were 49 variables, based on animal, flock or farm level. There was an enhanced risk of coccidiosis due to environmental and management factors that increase the risk of introducing contamination or that are related to hygienic measures. These include lack of use of overalls by visitors, a farmyard which is difficult to clean, bad hygienic status, personnel who might also be working on other farms, presence of other animals on the farm, and feeding and drinking systems which are more difficult to clean. Also, the presence of other diseases on the farm and Eimeria species found in the previous flock increased the risk of coccidiosis.  相似文献   

3.
The term Johne's disease immediately brings to mind an image of an emaciated, debilitated ruminant with bottlejaw and fluid, pipestream diarrhea. However, the clinical case is merely the tip of the iceberg in terms of the total number of infected animals on the farm. If the clinically affected animal was born on the farm, a minimum of 25 other animals are probably infected and less than 30% of those will be detectable by currently available tests. Infected animals in the early stages of the disease progress slowly over a period of months or several years to stages that may be detected by antigen detection tests and antibody-based diagnostic tests. The duration of each stage of infection depends on age at the time of exposure and the dose of organisms ingested. The lack of tests sensitive enough to detect infected animals in the earliest stages of disease is a serious obstacle to eradication of Johne's disease. The animals with overt infection may be culled from the herd immediately on detection. However, the animals that are shedding organisms below the threshold of detectability and have not mounted an immune response remain behind to contaminate the environment and infect herdmates.  相似文献   

4.
The prevalance of subclinical Johne's disease was estimated in adult cattle slaughtered at three major abattoirs in south west England. A polymerase chain reaction (PCR) based on IS900 was used to detect Mycobacterium paratuberculosis in intestinal lymph nodes of 1553 cattle. Culture was also carried out on all PCR positive and inconclusive samples. The prevalence of subclinical disease in adult cattle was 3.5% (95% confidence intervals (CI) 2.6-4.7) by PCR and 2.6% (CI 1.8-3.6) by culture. The proportion of the disease in each month ranged from 1.6% (CI 0.2-5.5) in April to 4.6% (CI 2.8-6.9) in November, but the difference was not significant (P > 0.05). The proportion of PCR positive lymph nodes in each abattoir ranged from 2.8% (CI 1.6-4.6) to 4.9% (CI 2.9-7.6), this difference was not significant either (P > 0.05). The prevalence in young cattle was 2.0% (CI 0.6-4.5). The difference between age groups was not statistically significant (P > 0.05).  相似文献   

5.
An extensive questionnaire was developed and used to collect data from 33 herds that were on the New York State Paratuberculosis Control Program, to study farm factors associated with the presence of Mycobacterium paratuberculosis infection in dairy herds. The results of the last whole herd paratuberculosis fecal culture were used to indicate presence of infection in a herd, with herds having one or more animals positive classified as 'infected'. The average prevalence within herds was 5.2%. Fourteen herds were uninfected and 19 herds had prevalences ranging from 0.7%-28.2%. Data on 31 continuous and 67 categorical risk factors were collected by questionnaire. Ten factors were significantly associated with prevalence risk of infection in the univariable logistic regression. These factors were: the type of farm operation (commercial/registered or both); earlier diagnosis of the disease before entering the control program; number of clinical cases in the previous year; whether clinical cases were raised or purchased animals; typical signs in clinical cases; exposure of calves 0-6 weeks of age to feces of adult cows; contact of young stock with adult animal feces from using the same equipment to clean the housing for both groups of animals; spreading feces on fields from which forage is later harvested and fed to animals of any age group; what is done with animals that are suspected of having paratuberculosis or test positive on culture; and frequency of cleaning the cow barn. Stepwise logistic regression was used to determine the significance of each risk factor while controlling simultaneously for the effect of other factors. The significant factors were the type of farm operation, clinical signs, and exposure of calves to feces of adult cows. Commercial herds, presence of clinical signs typical of paratuberculosis in animals, and exposure of calves 0-6 weeks old to feces of adult cows all indicate a higher likelihood that a herd is infected with M. paratuberculosis.  相似文献   

6.
Exposure to a number of environmental, behavioral and sociodemographic variables has been associated with increased prevalence and severity of adult periodontitis. However, it is not possible easily to identify the individuals most susceptible to this chronic disease. A case control study was conducted among a population of adults to determine what factors were associated with increased prevalence of moderate to advanced periodontitis. Clinical and radiographic data were obtained from dental charts and structured interviews were conducted by telephone to collect sociodemographic and behavioral data. Statistical modeling was completed for the total study population (35-87-year-olds) and for two age-stratified subpopulations. Significant crude disease associations were observed between periodontitis and numerous explanatory variables. However, after adjustment for age and gender, few variables remained significant. Age stratification indicated that young adults (35-54 years) were affected differently from older adults (> or =55 years) by exposures to certain variables. Young moderate smokers had a 3.15 times increased risk of periodontitis and young heavy smokers had a 7.33 times increased risk compared to never-smokers. Older single adults had a 3.07 times increased risk compared to those with partners.  相似文献   

7.
BACKGROUND: Homeless individuals experience high mortality rates. Males, whites, and substance abusers are more likely to die, but other high-risk characteristics are unknown. OBJECTIVE: To identify demographic and clinical factors associated with an increased risk of death in homeless individuals. METHODS: We conducted a case-control study of 558 adults who were seen by a health care program for the homeless in Boston, Mass, and who died in 1988 to 1993. Age-matched paired controls were selected from among individuals seen by the program who were alive at the end of 1993. Predictive data were obtained by blinded review of medical records. Odds ratios (ORs) for death were calculated using logistic regression analysis models. RESULTS: In a multivariate analysis, the strongest risk factors for death were acquired immunodeficiency syndrome (OR, 55.8), symptomatic human immunodeficiency virus infection (OR, 17.7), asymptomatic human immunodeficiency virus infection (OR, 4.1), renal disease (OR, 18.4), a history of cold-related injury (OR, 8.0), liver disease (OR, 3.8), and arrhythmia (OR, 3.3). A history of substance abuse involving injection drugs (OR, 1.6) or alcohol (OR, 1.5) also increased the risk of mortality. Nonfluency in English was associated with a decreased risk of death (OR, 0.4). CONCLUSIONS: In a group of adults seen by a health care program for the homeless, specific medical illnesses were associated with the greatest risk of death. Substance abuse alone was less strongly associated with death. Interventions to reduce mortality among the homeless should focus on individuals with high-risk characteristics.  相似文献   

8.
The actual prevalence of visceral leishmaniasis among human immunodeficiency type 1 (HIV-1)-infected patients in the Mediterranean basin remains unknown. There is also controversy about the risk factors for Leishmania infantum and HIV-1 coinfection. To appraise the prevalence of visceral leishmaniasis in patients infected with HIV-1 in southern Spain and to identify factors associated with this disease, 291 HIV-1 carriers underwent a bone marrow aspiration, regardless of their symptoms. Giemsa-stained samples were searched for Leishmania amastigotes. Thirty-two (11%) patients showed visceral leishmaniasis. Thirteen (41%) patients had subclinical cases of infection. Centers for Disease Control and Prevention (CDC) clinical category C was the factor most strongly associated with this disease (adjusted odds ratio [OR], 1.88 [95% confidence interval, 1.22 to 2.88]), but patients with subclinical cases of infection were found in all CDC categories. Female sex was negatively associated with visceral leishmaniasis (adjusted OR, 0.42 [95% confidence interval, 0.18 to 0.97]). Intravenous drug users showed a higher prevalence than the remaining patients (13.3 versus 4.9%; P = 0.04), but such an association was not independent. These results show that visceral leishmaniasis is a very prevalent disease among HIV-1-infected patients in southern Spain, with a high proportion of cases being subclinical. Like other opportunistic infections, subclinical visceral leishmaniasis can be found at any stage of HIV-1 infection, but symptomatic cases of infection appear mainly when a deep immunosuppression is present. There is also an association of this disease with male sex and intravenous drug use.  相似文献   

9.
OBJECTIVE: Investigate risk factors for colon polyp using multivariate analyses. DESIGN: In a group responding to a 1992 mail survey, we assessed the association between physician-diagnosed colon polyp and possible risk factors reported primarily 10 years earlier. SETTING: Survey respondents within the Cancer Prevention Study II. PARTICIPANTS: Respondents, 72,868 men and 81,356 women, who reported no polyp diagnosis when questioned in 1982 at ages 40 to 64 years. MEASUREMENTS AND MAIN RESULTS: The characteristics of 7,504 men (10.3%) and 5,111 women (6.3%) reporting a first colon polyp were compared with those of participants who did not report a polyp. After adjustments for age, family history of colorectal cancer, and other potential risk factors, polyp occurrence was associated with 1982 histories of smoking, former smoking, alcohol use of at least two drinks per day (odds ratios [ORs] from 1.5 to 1.1; all p < .005), and a body mass index > or = 28 kg/m2 (men's OR 1.06; 95% confidence interval [CI] 1.00, 1.13; women's OR 1.08; 95% CI 0.99, 1.17). Polyps were also associated with a diagnosis of gallbladder disease or gallstone at any time and with gallbladder surgery up to 1982 (OR from 2.7 to 1.3; all p < .001). Polyp occurrence was inversely associated with 1982 histories of high exercise level (men's OR 0.83; 95% CI 0.76, 0.91; women's OR 0.90; 95% CI 0.78, 1.03), frequent aspirin use in women (OR 0.85; 95% CI 0.77, 0.95), and high parity in women (OR 0.84; 95% CI 0.75, 0.94). Among participants lacking a clinically normal gallbladder, the polyp risks associated with smoking and high body mass index were reduced (p < .04 for interactions). CONCLUSIONS: Despite the limitations and potential biases in these self-reported data, the risk factors described here may be useful for identifying persons at modestly increased risk of having a colon polyp. The effect-modifying role of gallbladder status deserves further investigation.  相似文献   

10.
Atrial fibrillation (AF) is a common arrhythmia in elderly persons and a common cause of embolic stroke. Most studies of the prevalence and correlates of AF have used selected, hospital-based populations. The Cardiovascular Health Study is a population-based, longitudinal study of risk factors for coronary artery disease and stroke in 5,201 men and women aged > or = 65 years. AF was diagnosed in 4.8% of women and in 6.2% of men at the baseline examination, and prevalence was strongly associated with advanced age in women. Prevalence of AF was 9.1% in men and women with clinical cardiovascular disease, 4.6% in patients with evidence of subclinical but no clinical cardiovascular disease, and only 1.6% in subjects with neither clinical nor subclinical cardiovascular disease. A history of congestive heart failure, valvular heart disease and stroke, echocardiographic evidence of enlarged left atrial dimension, abnormal mitral or aortic valve function, treated systemic hypertension, and advanced age were independently associated with the prevalence of AF. The low prevalence of AF in the absence of clinical and subclinical cardiovascular disease calls into question the existence and clinical usefulness of the concept of so-called "lone atrial fibrillation" in the elderly.  相似文献   

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13.
Four cases of concomitant animal and human Salmonellosis were investigated. Liaison took place between veterinary, public health medical and environmental health professionals. An epidemiological association between veterinary and medical disease outbreaks was established following cases in a dairy unit, a poultry unit, a calf rearing unit and one pig and dairy unit (on the same farm). In three cases clinical disease in animals preceded clinical disease in humans while in the fourth case, the poultry unit, salmonella isolations from poultry carcasses coincided with clinical salmonellosis in a human working with the live poultry. Important epidemiological factors are identified. The problems of delay in seeking veterinary advice, compartmentalisation of veterinary and medical practices, and the benefits of direct collaboration between veterinary and medical professionals in the event of a diagnosis of salmonellosis in animals and/or humans are highlighted. A collaborative reporting and liaison model is proposed.  相似文献   

14.
Peripheral blood mononuclear cells were isolated from noninfected control cows and from cows with either subclinical or clinical paratuberculosis (Johne's disease). Cells were incubated for 6, 12, 24, and 48 hours in complete medium with the following mitogens: concanavalin A (ConA), phytohemagglutinin-P (PHAP), pokeweed mitogen (PWM), and Escherichia coli lipopolysaccharide. In addition, cells were incubated for the same time periods with a Mycobacterium paratuberculosis sonicate (MpS) and live and heat-killed M. paratu-berculosis at 10:1 bacteria: cell ratio. After incubation, cell-free supernatants were analyzed for gamma-interferon (gamma-IFN) production. Cells from subclinical cows produced significantly higher levels of gamma-IFN than did cells from clinical animals after stimulation with mitogens ConA, PHAP, and PWM. Levels of gamma-IFN produced by noninfected control animals generally followed the pattern of those of subclinical animals. After incubation with MpS, significantly greater quantities of gamma-IFN were produced by cells isolated from subclinical animals than by cells from clinical cows and noninfected controls. Stimulation of cells with heat-killed or live M. paratuberculosis evoked a similar response. This study indicates that gamma-IFN production by peripheral blood mononuclear cells in response to M. paratuberculosis antigen may be an important diagnostic tool for the detection of paratuberculosis in subclinically affected animals.  相似文献   

15.
Musculoskeletal disorders (MSDs) constitute more than half of the total injuries and illnesses within the construction industry. The aim of this study was to assess the prevalence of MSD among construction workers and identify the psychosocial and physical risk factors associated with their occurrence using an on-site survey instrument. One hundred forty seven construction workers (representing three trades) participated in the study. The 1-year prevalence of MSD was high with 61.2% reporting severe symptoms and 39.7% having some functional impairment due to MSD. Physical task requirement was the most important factor associated with MSD reflecting the physical nature of construction work. Economic and performance factors were the most stressful psychosocial factors reported and significantly increased the risk of reporting MSD. The findings of this research underscore the independent role that psychosocial factors play in the health and safety of construction workers. Understanding this role is imperative for practitioners and academics alike in the quest to make construction a safer work environment for all workers.  相似文献   

16.
OBJECTIVE: To assess the risk of Johne's disease not being detected in sheep imported from New South Wales into Western Australia. DESIGN: A stochastic simulation model. PROCEDURE: The process of importing sheep was broken down into steps and numbers or probabilities assigned to each. Controls on the movement of sheep included surveillance tests in source flocks and serological tests on sheep in consignments before and after transportation to Western Australia. The model calculated the risk of occurrence of Johne's disease in Western Australia and the success of the agar gel immunodiffusion test in identifying consignments with infected sheep. RESULTS: Negative surveillance tests in source flocks reduced the risk to about one twentieth of that when no surveillance tests were required. On average, Johne's disease was predicted to be introduced once in every 3 to 7 years when no testing of either the source flock or the sheep in consignments was required. When negative surveillance tests only were required the interval increased to once in every 63 to 111 years and, with the additional requirement that all sheep in each consignment must have a negative test before and after transport, the interval further increased to once in every 125 to 333 years. When only sheep in consignments were tested, the interval was calculated to be 8 to 14 years. CONCLUSION: A requirement that imports be derived from flocks which had negative surveillance tests to Johne's disease would provide significantly greater protection for the sheep industry in Western Australia.  相似文献   

17.
OBJECTIVE: To identify the prevalence of chorioaminionitis and unique risk factors for this disorder among adolescents under 18 years of age. METHODS: At their first prenatal visit we interviewed 352 adolescents who received prenatal care and delivered an infant at our institution between April 20, 1992, and November 10, 1994, to elicit information on demographic characteristics and behavioral risk factors. Retrospective chart review confirmed the presence of chorioamnionitis using accepted clinical criteria. We determined reproductive history, evidence of sexually transmitted disease, duration of labor, use of oxytocin, an internal uterine pressure monitor or conduction anesthesia, timing and duration of ruptured membranes, type of delivery, and infant birth weight from review of subjects' charts. Logistic regression analysis was used to develop adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for risk factors of chorioaminionitis. RESULTS: Ten percent (34 of 352) of adolescents met the clinical definition for chorioamnionitis. Alcohol and tobacco use during pregnancy (OR 7.6; 95% CI 2.3, 25.8) and being married or living with a partner (OR 2.7; 95% CI 1.1, 6.5) were significantly associated with chorioamnionitis, as was conduction anesthesia (OR 4.1; 95% CI 1.1, 15.4), a second stage labor longer than 2 hours (OR 3.5; 95% CI 1.4, 8.5), and rupture of the membranes longer than 18 hours (OR 6.9; 95% CI 2.5, 18.9). Parity or preterm delivery did not differ significantly between those with or without chorioamnionitis. CONCLUSION: These data suggest that in addition to risk factors observed in adults, adolescents who concurrently use tobacco and alcohol during pregnancy, are married or living with a male partner, and have conduction anesthesia are at increased risk for chorioamnionitis.  相似文献   

18.
A case-control investigation of the risk factors for Salmonella dublin infections on 126 dairy farms identified the following variables as being significantly associated with infection: standardized farm size and presence of water courses. Contrary to expectations, contact with cattle from other farms when the animals were turned out to grass was negatively associated with S. dublin infection. The purchase of cattle from other farms was a risk factor. There were more infections when feed consisted of grass alone than when grass was supplemented with maize or grass silage. S. dublin infections were strongly correlated with liver fluke infections.  相似文献   

19.
This study examined the association between a composite index of stress that included measures of life events, ongoing stress, discrimination, and economic hardship and subclinical carotid disease among 109 African American and 225 Caucasian premenopausal women. African Americans reported more chronic stress and had higher carotid intima-media thickness (IMT) as compared with Caucasians. Among African Americans only, the composite stress index and unfair treatment were associated with higher IMT. These effects were partially mediated by biological risk factors. African Americans who reported experiencing racial discrimination had marginally more carotid plaque than did those who did not report experiencing racial discrimination. The results suggest that African Americans may be particularly vulnerable to the burden of chronic stress. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
OBJECTIVE: The aim of this research was to determine whether and in whom stressors and depressive symptoms facilitate clinical recurrence of herpes simplex virus (HSV) and progression of HIV. METHOD: Meta-analytic techniques were used to review the relations of stressors and depressive symptoms to clinical recurrence of HSV in 16 published studies and to indicators of HIV progression in 19 published studies. The authors calculated average effect sizes, performed fixed effect and random effect inferential analyses, tested for heterogeneous findings, and identified potential moderating variables. RESULTS: Depressive symptoms were associated with a slightly increased risk of HSV recurrence and increased reports of HIV-related symptoms, whereas stressors were not. However, depressive symptoms were not associated with objective indicators of accelerated HIV progression. Stressor studies, especially those that ascertained population-specific life events, found numerical and functional decrements in circulating natural killer cell populations. The candidate moderators identified include, for HSV recurrence, age, sex, and medication status, and for HIV-related symptoms, age, race, disease stage, and co-infection with HSV. CONCLUSIONS: Depressive symptoms, but not stressors, increase the risk of HSV recurrence generally. Depressive symptoms do not appear to accelerate HIV progression ubiquitously, although they are associated with increased reporting of HIV-related symptoms. Future studies that ascertain population-specific stressors should determine whether reductions in cytotoxic lymphocytes influence HIV disease progression. Moreover, researcher should investigate the role of the identified moderators and recognize psychoimmune moderators in existing and novel study groups. These analyses could confirm that certain individuals are especially susceptible to the effects on disease progression of stressors, depressive symptoms, or both.  相似文献   

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