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991.
992.
BACKGROUND: Although atherosclerotic renovascular disease is increasingly recognized in chronic kidney disease, few national level studies have examined its clinical epidemiology. METHODS: Claims data from a 5% random sample of the United States Medicare population were used to select patients without atherosclerotic renovascular disease in the 2 years preceding December 31, 1999 (N= 1,085,250), followed until December 31, 2001. RESULTS: The incidence of atherosclerotic renovascular disease was 3.7 per 1000 patient-years. Major antecedent associations [P < 0.05, with adjusted hazards ratios (HR) > 1.5] included chronic kidney disease (adjusted HR 2.54), hypertension (2.42), peripheral vascular disease (2.00), and atherosclerotic heart disease (1.70). Adverse event rates after incident atherosclerotic renovascular disease greatly exceeded those in the general population (P < 0.0001): atherosclerotic heart disease, 303.9 per 1000 patient-years (vs. 73.5 in the general population); peripheral vascular disease, 258.6 (vs. 52.2); congestive heart failure, 194.5 (vs. 56.3); cerebrovascular accident or transient ischemic attack, 175.5 (vs. 52.9); death, 166.3 (vs. 63.3); and renal replacement therapy, 28.8 (vs. 1.3). Among atherosclerotic renovascular disease patients, 16.2% underwent a renal revascularization procedure, percutaneously in 96%. Revascularization was not associated with renal replacement therapy, congestive heart failure, or death but was associated with atherosclerotic heart disease (adjusted HR 1.42) (P= 0.004) and peripheral vascular disease (adjusted HR 1.38) (P= 0.002). CONCLUSION: Atherosclerotic renovascular disease is strongly associated with cardiovascular disease, both past and future. Absolute cardiovascular risk exceeds that of renal replacement therapy. Renal revascularization is used selectively and shows inconsistent associations with cardiovascular outcomes, renal replacement therapy, and death.  相似文献   
993.
BACKGROUND: Microinflammation is linked to cardiovascular disease, and is highly prevalent in dialysis patients. It is logical to postulate that septicemia, a common macroinflammatory occurrence in dialysis patients, contributes to their large burden of cardiovascular disease. METHODS: The Dialysis Morbidity and Mortality Wave 2 was a randomly selected prospective cohort of incident dialysis patients. Admission claims data were used to define and calculate rates of septicemia or bacteremia and cardiovascular events in those with Medicare as the primary payer. Utilizing Cox proportional hazard models we determined the association between baseline access and the development of bacteremia or sepsis, and also the association between bacteremia or sepsis episodes and subsequent cardiovascular events. RESULTS: The 2358 (59%) patients with Medicare as primary payer were older and more likely to have heart failure than those with other payers, but had similar comorbidity-adjusted mortality hazards. Rates of first septicemia, bacteremia, or either condition, were 7.0, 5.9 and 10.4 events per 100-patient years, respectively. Cox regression identified initial dialysis access as the main antecedent of septicemia or bacteremia. Hazards ratios for hemodialysis with permanent catheters, temporary catheters, and grafts were 1.95 (95% CI 1.47-2.57), 1.76 (95% CI 1.29-2.41), and 1.05 (95% CI 0.82-1.35), respectively, while that for peritoneal dialysis was 0.96 (95% CI 0.75-1.23) (reference arteriovenous fistula). After adjustment for baseline factors, septicemia or bacteremia, as a time-dependent covariate, was associated with subsequent death [hazards ratio (HR) 2.33, 95% CI 1.38-2.28], myocardial infarction (HR 1.78, 95% CI 1.38-2.28), heart failure (HR 1.64, 95% CI 1.39-1.95), peripheral vascular disease (HR 1.64, 95% CI 1.34-2.0), and stroke (HR 2.04, 95% CI 1.27-3.28). CONCLUSION: Septicemia appears to be an important, potentially preventable, cardiovascular risk factor in dialysis patients.  相似文献   
994.
BACKGROUND: Corporate performance-improvement methodologies can outperform traditional ones in addressing ICU-based adverse events. My colleagues and I used Six Sigma methodology to address our catheter-related bloodstream infection (CR-BSI) rate, which considerably exceeded the nationally established median over a 9-year period. We hypothesized that use of Six Sigma methodology would result in a substantial and sustainable decrease in our CR-BSI rate. STUDY DESIGN: All patients were directly cared for by a geographically localized surgical ICU team in an academic tertiary referral center. CR-BSIs were identified by infection control staff using CDC definitions. Personnel trained in Six Sigma techniques facilitated performance-improvement efforts. Interventions included barrier precaution kits, new policies for catheter changes over guide wires, adoption of a new site-preparation antiseptic, direct attending supervision of catheter insertions, video training for housestaff, and increased frequency of dressing changes. After additional data analysis, chlorhexidine-silver catheters were used selectively in high-risk patients. The impact of interventions was assessed by monitoring the number of catheters placed between CR-BSIs. RESULTS: Before the intervention period, 27 catheters were placed, on average, between individual CR-BSIs, a CR-BSI rate of 11 per 1,000 catheter days. After all operations were implemented, 175 catheters were placed between line infections, and average CR-BSI rate of 1.7/1,000 catheter days, a 650% improvement (p < 0.0001). Compared with historic controls, adoption of chlorhexidine-silver catheters in high-risk patients had a considerable impact (50% reduction; p < 0.05). CONCLUSIONS: This represents the first successful application of Six Sigma corporate performance-improvement method impacting purely clinical outcomes. CR-BSI reduction was highly substantial and sustained after other traditional strategies had failed.  相似文献   
995.
OBJECTIVE: To determine whether the outcomes of liver transplantation (LTx) from donation after cardiac death (DCD) donors are equivalent to those from donation after brain death (DBD) donors. SUMMARY BACKGROUND DATA: Because of the significant donor organ shortage, more transplant centers are using livers recovered from DCD donors. However, long-term, single-center outcomes of liver transplantation from DCD donors are limited. METHODS: From January 1, 1993, to July 31, 2002, 553 liver transplants were performed from DBD donors and 36 were performed from DCD donors. Differences in event rates between the groups were compared with Kaplan-Meier estimates and the log-rank test. Differences in proportion and differences of means between the groups were compared with Fisher exact test and the Wilcoxon rank sum test, respectively. RESULTS: Mean warm ischemic time at recovery in the DCD group was 17.8 +/- 10.6 minutes. The overall rate of biliary strictures was greater in the DCD group at 1 year (33% versus 10%) and 3 years (37% versus 12%; P = 0.0001). The incidence of hepatic artery thrombosis, portal vein stenosis/thrombosis, ischemic-type biliary stricture (ITBS), and primary nonfunction were similar between groups. However, the incidence of both hepatic artery stenosis (16.6% versus 5.4%; P = 0.001) and hepatic abscess and biloma formation (16.7% versus 8.3%; P = 0.04) were greater in the DCD group. Trends toward worse patient and graft survival and increased incidence of ITBS were seen in DCD donors greater than 40 years compared with DCD donors less than 40 years. Overall patient survival at 1 year (DCD, 80%; versus DBD, 91%) and 3 years (DCD, 68%; versus DBD, 84%) was significantly less in the DCD group (P = 0.002). Similarly, graft survival at 1 year (DCD, 67%; versus DBD, 86%) and 3 years (DCD, 56%; versus DBD, 80%) were significantly less in the DCD group (P = 0.0001). CONCLUSIONS: Despite similar rates of primary nonfunction, LTx after controlled DCD resulted in worse patient and graft survival compared with LTx after DBD and increased incidence of biliary complications and hepatic artery stenosis. However, overall results of LTx after controlled DCD are encouraging; and with careful donor and recipient selection, LTx after DCD may successfully increase the donor liver pool.  相似文献   
996.
The purpose of this report is to provide further information about vaccine information statements (VISs) that are revolutionary but neglected educational advances in the United States. Because the use of VISs is mandated by the Federal Government in every individual being immunized, it is the goal of this report to further awaken health professionals and society to the mandatory use of these superb educational statements. With the passage of the National Childhood Vaccine Injury Act of 1986, the Federal Government required that VISs would be given to all vaccine recipients. As of September 2001, the VISs that must be used are diphtheria, tetanus, pertussis, (DTaP); diphtheria, tetanus (Td); measles, mumps, rubella (MMR); polio (IPV); hepatitis B; Haemophilus influenzae type b (Hib); varicella; and pneumococcal conjugate. Copies of the VISs are available at www.cdc.gov/nip/publications/VIS. The National Childhood Vaccine Injury Act of 1986 mandated that all health care providers report certain adverse events that occur following vaccination. As a result, the Vaccine Adverse Events Reporting System (VAERS) was established by the FDA and the Centers for Disease Control and Prevention (CDC) in 1990. In order to reduce the liability of manufacturers and healthcare providers, the National Childhood Vaccine Injury Act of 1986 established the National Vaccine Injury Compensation Program (NVICP).This program is intended to compensate those individuals who have been injured by vaccines on a no-fault basis. While the use of VISs has been mandated since 1996, a national survey of private practice office settings has revealed that many immunized patients do not receive the VISs. When these forms were used, physicians rarely initiated discussions regarding contraindications to immunizations or the National Vaccine Injury Compensation Program. Fortunately, the state boards of medical examiners, like the one in Oregon, are taking a strong stand for the use of VISs, with the warning that failure to use a VIS may result in disciplinary action. Our nation and practicing physicians must be awakened to the importance of the use of VISs to ensure that every vaccinated individual receives this statement at the time of vaccination.  相似文献   
997.
998.
999.
This paper reports the results of a practice-based intervention program to increase mammography screening among women 65 and older who receive their health care in the private sector. Forty-three primary-care practices and 2147 women in central and western North Carolina were enrolled in the study, and 1911 women completed all phases of the study. The intervention was a three-stage educational and counseling program designed to become progressively more intensive at each stage. The interventions included provider education in the form of current information on issues in mammography for older women, simply written educational materials on breast cancer and screening mailed to women, and a brief telephone counseling session for the women. While the analysis revealed no overall effect across all three stages of the intervention program, tests for interaction indicated a significant program effect for women who were 80 or older, had less than 9 years of education, were black, or had no private insurance to supplement Medicare. The results suggested that providing primary-care physicians with information on screening older women and providing the women with useful educational materials can increase participation in screening mammography among subgroups of women currently least likely to receive mammography screening.  相似文献   
1000.
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