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81.
"Reverse epidemiology" refers to paradoxical and counterintuitive epidemiologic associations between survival outcomes and traditional cardiovascular risk factors such as obesity, high blood pressure, and high cholesterol. Reverse epidemiology has been well described in end stage renal disease, but also has been observed in chronic disease states, including chronic heart failure, rheumatoid arthritis, chronic obstructive pulmonary disease, and Acquired Immune Deficiency Syndrome, and in elderly populations. This review will highlight the recent medical literature on reverse epidemiology in these populations. Common pathophysiologic underpinnings in these chronic disease states may help explain the reversal of risk factors observed in these diverse populations. Furthermore, guidelines for the general population for optimal goals of weight, cholesterol levels, and blood pressure may not apply to special populations, including patients with chronic diseases or elderly persons.  相似文献   
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Although loop diuretics are widely used in heart failure (HF), their effect on outcomes has not been evaluated in large clinical trials. This study sought to determine the dose-dependent relation between loop diuretic use and HF prognosis. A cohort of 1,354 patients with advanced systolic HF referred to a single center was studied. Patients were divided into quartiles of equivalent total daily loop diuretic dose: 0 to 40, 41 to 80, 81 to 160, and >160 mg. The cohort was 76% male, with a mean age of 53+/-13 years and a mean ejection fraction of 24+/-7%. The mean diuretic dose equivalence was 107+/-87 mg. The diuretic quartile groups were similar in terms of gender, body mass index, ischemic cause of HF, history of hypertension, and spironolactone use, but the highest quartile was associated with a smaller ejection fraction and lower serum sodium and hemoglobin levels but higher serum blood urea nitrogen and creatinine levels. There was a decrease in survival with increasing diuretic dose (83%, 81%, 68%, and 53% for quartiles 1, 2, 3, and 4, respectively). Even after extensive co-variate adjustment (age, gender, ischemic cause of HF, the ejection fraction, body mass index, pulmonary capillary wedge pressure, peak oxygen consumption, beta-blocker use, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use, digoxin use, statin use, serum sodium, blood urea nitrogen, creatinine, hemoglobin, cholesterol, systolic blood pressure, and smoking history), diuretic quartile remained an independent predictor of mortality (quartile 4 vs quartile 1 hazard ratio 4.0, 95% confidence interval 1.9 to 8.4). In conclusion, in this cohort of patients with advanced HF, there was an independent, dose-dependent association between loop diuretic use and impaired survival. Higher loop diuretic dosages identify patients with HF at particularly high risk for mortality.  相似文献   
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汪爱民  杨建安 《安徽医学》2004,25(5):383-385
目的 了解我省项目工作的现状及项目工作对我省结防工作的影响。方法 根据 2 0 0 2~ 2 0 0 3年《中国结核病控制工作季报表》和《结核病人登记调查表》 ,分析项目病人的发现、治疗等情况。结果  2 0 0 3年项目地区肺结核、涂阳肺结核登记率分别为 5 3 .4/10万、2 0 .0 /10万 ,分别高于非项目地区 44 .7%、10 0 % ;2 0 0 2年项目地区涂阳肺结核病人治愈率 78.5 % ,明显高于非项目地区。结论 项目工作取得了显著成果 ,为我省其它地区实施项目工作提供了经验 ,为我省结核病控制工作的可持续发展打下了基础。  相似文献   
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目的对2009年10~12月武汉市结核病防治所住院的痰标本直接涂片抗酸杆菌镜检阳性(涂阳)肺结核患者诊断延误及其影响因素进行研究。方法采用自行设计的问卷,对224例涂阳肺结核患者进行面访式调查。采用Wilcoxon符号秩和检验对首诊延误、卫生系统延误及诊断延误分别进行单因素分析,用逐步logistic回归法对3种延误分别进行多因素分析。结果首诊延误、卫生系统延误及诊断延误中位数分别为8、12及35 d;首诊延误的危险因素为:男性(OR=2.134,95%可信区间1.115~4.083),初中及以下文化(OR=1.879,95%可信区间1.048~3.368),无咯血(OR=2.194,95%可信区间1.056~4.559)及结核知识得分低(OR=4.060,95%可信区间2.232~7.385);卫生系统延误危险因素为:首诊为区以下医疗单位(OR=2.938,95%可信区间1.339~6.446),保护因素为:就诊次数≤1次(OR=0.056,95%可信区间0.025~0.126);诊断延误危险因素为结核知识得分低(OR=3.036,95%可信区间1.654~5.572),自卑及自我羞耻感水平高(OR=2.012,95%可信区间1.103~3.676),保护因素为:就诊次数≤1次(OR=0.216,95%可信区间0.117~0.396)。结论武汉市住院涂阳肺结核患者存在一定的诊断延误,但延误水平不高。应加强对人群特别是文化程度低的人群的结核相关知识宣教;加强基层医务人员对结核病的警觉性并提高诊断能力;应避免患者反复多次就诊于同一水平医疗机构,从而缩短诊断延误时间。  相似文献   
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PURPOSE: To assess long-term site-specific risks of second malignancy after Hodgkin's disease in relation to age at treatment and other factors. PATIENTS AND METHODS: A cohort of 5,519 British patients with Hodgkin's disease treated during 1963 through 1993 was assembled and followed-up for second malignancy and mortality. Follow-up was 97% complete. RESULTS: Three hundred twenty-two second malignancies occurred. Relative risks of gastrointestinal, lung, breast, and bone and soft tissue cancers, and of leukemia, increased significantly with younger age at first treatment. Absolute excess risks and cumulative risks of solid cancers and leukemia, however, were greater at older ages than at younger ages. Gastrointestinal cancer risk was greatest after mixed-modality treatment (relative risk [RR] = 3.3; 95% confidence interval [CI], 2.1 to 4.8); lung cancer risks were significantly increased after chemotherapy (RR = 3. 3; 95% CI, 2.4 to 4.7), mixed-modality treatment (RR = 4.3; 95% CI, 2.9 to 6.2), and radiotherapy (RR = 2.9; 95% CI, 1.9 to 4.1); breast cancer risk was increased only after radiotherapy without chemotherapy (RR = 2.5; 95% CI, 1.4 to 4.0); and leukemia risk was significantly increased after chemotherapy (RR = 31.6; 95% CI, 19.7 to 47.6) and mixed-modality treatment (RR = 38.1; 95% CI, 24.6 to 55. 9). These risks were generally greater after treatment at younger ages: for patients treated at ages younger than 25 years, there were RRs of 18.7 (95% CI, 5.8 to 43.5) for gastrointestinal cancer after mixed-modality treatment, 14.4 (95% CI, 5.7 to 29.3) for breast cancer after radiotherapy, and 85.2 (95% CI, 45.3 to 145.7) for leukemia after chemotherapy (with or without radiotherapy). CONCLUSION: Age at treatment has a major effect on risk of second malignancy after Hodgkin's disease. Although absolute excess risks are greater for older patients, RRs of several important malignancies are much greater for patients who are treated when young. The increased risk of gastrointestinal cancers may relate particularly to mixed-modality treatment, and that of lung cancer to chemotherapy as well as radiotherapy; there are also well-known increased risks of breast cancer from radiotherapy and leukemia from chemotherapy. The roles of specific chemotherapeutic agents in the etiology of solid cancers after Hodgkin's disease require detailed investigation.  相似文献   
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