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171.
OBJECTIVE: Upper GI bleeding (UGIB) is a common medical emergency that leads to a high consumption of medical resources and costs. We aimed to analyze the influence of physician specialty on the costs of nonvariceal UGIB care. METHODS: We retrospectively assessed 350 nonvariceal UGIB episodes that were primarily cared for by gastroenterologists (n = 142), internists (n = 67), or surgeons (n = 141). Gastroenterologists followed evidence-based clinical protocols that included early endoscopy and early hospital discharge for uncomplicated bleeding. A risk score system was used to control for severity of illness. Linear regression analyses were performed to find out predictors of costs and the influence of specialist care on length of stay (LOS). RESULTS: The overall mean hospital cost was significantly lower in patients cared for by gastroenterologists (EUR 1,630) than in those managed by internists (EUR 3,745, p < 0.001) or surgeons (EUR 2,513, p < 0.05). The mean LOS was the variable with highest influence on total cost. Patients cared for by gastroenterologists had a mean LOS significantly shorter (7.3 days) than that of those treated by internists (16.2 days, p < 0.001) or surgeons (11 days, p < 0.001). Hospital costs and LOS differences were maintained when adjusting for severity of illness. In caring for low risk patients, nongastroenterologists had a higher probability of having a hospital stay longer than 4 days (odds ratio = 18.4, Cl = 4.6-73.6, p < 0.001). CONCLUSION: The implementation of specific evidence-based protocols by gastroenterologists reduces length of hospital stay and saves medical costs in patients with nonvariceal UGIB, especially those at low risk.  相似文献   
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INTRODUCTION AND OBJECTIVES: Some authors have described seasonal variations in the incidence of acute myocardial infarction. The aim of this study was to determine the existence of seasonal rhythms in admissions for acute myocardial infarction to coronary care units, and in mortality, and to analyze the influence of age on environmental factors. PATIENTS AND METHOD: The study included a total of 8400 consecutive patients with acute myocardial infarction admitted to 12 coronary care units in the PRIMVAC registry from January 1995 to December 1999. Seasonal rhythms were analyzed with the time series method and the Cosinor regression equation. The influence of age was analyzed with the chi 2 test. RESULTS: The total number of admissions increased in winter and decreased in summer. The highest peak (acrophase) occurred in winter, with 2183 cases (r2=0.91), specifically in February, with 742 cases (r2=0.66). The age of the patients conditioned seasonal variations (P=.006), and the influence was statistically significant for patients over 65 years of age. Changes in mortality with time did not reach statistical significance. CONCLUSIONS: A seasonal rhythm in admissions for acute myocardial infarction was found, with an increase in winter and a decrease in summer. Age conditioned the effect of environmental factors on acute myocardial infarction, and patients aged 65 years or older were more sensitive to mechanisms that led to increases in admissions in winter.  相似文献   
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Background Residual plaque burden after coronary stenting may be visualized by use of intravascular ultrasound. Determinants and implications of residual atherosclerotic plaque burden after coronary stenting are not well established. In particular, the implications of residual plaque burden, after adjusting for confounding factors, are still unknown. Methods Sixty-two consecutive patients (age 56 ± 9 years) undergoing coronary stenting under intravascular ultrasound imaging guidance were prospectively studied. A total of 616 slices were analyzed (every 2 mm of stent length) from motorized pull-back recordings. Residual plaque burden was calculated as residual plaque/vessel area × 100. Results In 565 slices (89%), both residual plaque area and stent area could be measured. Mean residual plaque burden was 46.5% ± 6%. By use of multiple regression analysis, lesion plaque area and reference segment plaque burden were identified as independent predictors of residual plaque burden after stenting. In addition, a significant correlation was found between residual plaque burden and most relevant angiographic parameters at follow-up (including minimal lumen diameter, percent diameter stenosis, and loss index), which persisted after adjustment. Furthermore, stents with a residual plaque burden ≥46% had higher a restenosis rate (relative risk [RR] 4.4, 95% CI 1.09-18.2, P = .03). On logistic regression analysis, residual plaque burden (RR 4.8, 95% CI 4.1-5.6, P = .01) and diabetes (RR 4.3, 95% CI 3.6-5.1, P = .03) emerged as the only independent predictors of restenosis. Conclusions The amount of residual plaque burden after coronary stenting plays an independent role on the late angiographic outcome of these patients. (Am Heart J 2003;145:254-61.)  相似文献   
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Amyloidosis is a disease resulting from extracellular deposition of fibrillar protein in various organs. AA amyloidosis may complicate chronic inflammatory diseases, chronic infections and another chronic diseases. We review 31 patients (13 males and 18 females) with biopsy proven renal or rectal AA amyloidosis, referred to out hospital between january 1999 and november 2002. Renal failure was defined as serum creatinine > or = 1.5 mg/dl. Mean age was 58.4 +/- 15.7 years. The causes of AA amyloidosis were an underlying chronic rheumatologic disease (51.6%), chronic infection (41.9%) and a chronic inflammatory intestinal disorder (6.5%). Renal failure (RF) was detected in 20 patients (61.2%) and proteinuria and hematuria were found in 90.3% and 45.5 respectively. Proteinuria at diagnosis was 5.2 +/- 3.9 g/24 h and mean serum creatinine 3.5 +/- 3.7 mg/dl. Survival of patients without dialysis was 66.8 (51.1% RF, 90.9% non-RF) and 53.4% (38.2 RF, 77.9% non-RF) at 12 and 24 months respectively (p = 0.017). End-stage renal disease developed in 13 patients (41.9%). Ten patients were maintained on hemodialysis and 3 on CAD. Survival in dialysis at 6 and 12 months was 68.3% and 42.7% respectively. Fifteen patients died and the main causes of death were: infections (46.6) haemorrhagic complications (33.3%), cardiovascular events (13.3%) and cachexia (6.6%).  相似文献   
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