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Background

Red blood cell transfusion benefit during acute myocardial infarction remains unclear in the elderly. We aimed to assess the transfusion impact on 1-year mortality in acute myocardial infarction patients aged ≥65 years, according to their age and hemoglobin nadir.

Methods

We included 3316 consecutive patients with acute myocardial infarction aged ≥65 years from the “obseRvatoire des Infarctus de Côte d'Or” (RICO) survey. They were categorized according to their hemoglobin nadir (≤8, >8 to ≤10, and >10 g/dL) and age (<80 or ≥80 years).

Results

A total of 1906 patients (57%) were 65-79 years old, and 1410 (43%) were aged ≥80 years, of whom 103 (5%) and 145 (10%) patients received red blood cell transfusion, respectively (P < .001). In Cox regression analysis, transfusion was associated with increased 1-year mortality for hemoglobin nadir >10 g/dL but no significant effect for hemoglobin nadir between 8 and 10 g/dL. When hemoglobin nadir was ≤8 g/dL, transfusion did not influence 1-year mortality for younger patients (65-79 years). However, for older patients (≥80 years), transfusion was associated with lower mortality (hazard ratio 0.43 [95% confidence interval, 0.22-0.86], P = .016).

Conclusion

Among older patients with acute myocardial infarction, the effect of transfusion was largely dependent on hemoglobin threshold and age. Transfusion was associated with increased 1-year mortality when hemoglobin nadir was >10 g/dL. However, in patients aged ≥80 years with hemoglobin nadir <8 g/dL, transfusion was associated with a 50% reduction in 1-year mortality.  相似文献   
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Blood donations in the United States have been screened for antibody to human T-lymphotropic virus type I (HTLV-I) by HTLV-I enzyme immunoassay (EIA) since November 1988. Specimens repeatedly found to be reactive by EIA undergo confirmation by supplementary serologic tests. We assessed the accuracy of blood center testing of 994 HTLV-I EIA repeat-reactive specimens in five US blood centers between November 1988 and December 1991. Of 410 confirmed HTLV-I/II donations, 407 (99.3%) were infected with HTLV-I/II, as determined by polymerase chain reaction (PCR) (403 cases) and by repeat serologic testing (4 cases). The three false- positive results occurred in the first year of testing. Of 425 HTLV- indeterminate specimens, 6 (1.4%) were found to be infected by PCR (5 with HTLV-II and 1 with HTLV-I). None of 159 confirmatory test-negative donations was PCR positive. Of HTLV-I/II-seropositive specimens, 80.2% to 95.4% could be typed as HTLV-I or HTLV-II by type-specific serologic assays. These results support recommendations that HTLV-I/II- seropositive donors should be advised that they are infected with HTLV- I, HTLV-II, or HTLV-I/II (depending on results of type-specific assays). HTLV-indeterminate donors should be advised that their results only rarely indicate HTLV infection. HTLV confirmatory test-negative donors should be reassured that they are not infected with HTLV-I or HTLV-II.  相似文献   
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Aims/hypothesis  

Translation of genetic association signals into molecular mechanisms for diabetes has been slow. The glucokinase regulatory protein (GKRP; gene symbol GCKR) P446L variant, associated with inverse modulation of glucose- and lipid-related traits, has been shown to alter the kinetics of glucokinase (GCK) inhibition. As GCK inhibition is associated with nuclear sequestration, we aimed to determine whether this variant also alters the direct interaction between GKRP and GCK and their intracellular localisation.  相似文献   
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The main purpose of this study was to determine the most robust predictor of mortality among global self-rated health (SRH), time-comparative SRH or a combination of both measures. We also sought to determine factors associated with global SRH and time-comparative SRH measures. A prospective cohort study of 5583 community-dwelling older men aged 70 years or over living in Perth, Western Australia, was used. Older age, depressive symptoms, low social support, sensory impairment, presence of pain, and high Charlson score index were associated with both SRH measures. Global and time-comparative SRH were independent predictors of all-cause mortality (adjusted hazard ratio, HR=1.24 vs. 1.41 respectively); and the risk of death was almost doubled in those with both negative global SRH and perception of worsening health over the preceding 12 months (adjusted HR 1.98, 95%CI 1.58-2.47). In this group, the rate of death was especially high during the initial four years of follow up. We concluded that the two measures of SRH are likely to reflect the same domains of health, and the simultaneous use of both measures is the best predictor of short to medium term mortality.  相似文献   
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Essential thrombocythemia, a myeloproliferative neoplasm, is associated with increased platelet count and risk of thrombosis or hemorrhage. Cytoreductive therapy aims to normalize platelet counts despite there being only a minimal association between platelet count and complication rates. Evidence is increasing for a correlation between WBC count and thrombosis, but prospective data are lacking. In the present study, we investigated the relationship between vascular complications and 21 887 longitudinal blood counts in a prospective, multicenter cohort of 776 essential thrombocythemia patients. After correction for confounding variables, no association was seen between blood counts at diagnosis and future complications. However, platelet count outside of the normal range during follow-up was associated with an immediate risk of major hemorrhage (P = .0005) but not thrombosis (P = .7). Elevated WBC count during follow-up was correlated with thrombosis (P = .05) and major hemorrhage (P = .01). These data imply that the aim of cytoreduction in essential thrombocythemia should be to keep the platelet count, and arguably the WBC count, within the normal range. This study is registered at the International Standard Randomized Controlled Trials Number Registry (www.isrctn.org) as number 72251782.  相似文献   
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