Biomedical subjects

M W Rosenblatt

Publications and source records attributed to M W Rosenblatt.

3 recordsLinked to original sources

PubMed1990

A bleeding risk index for estimating the probability of major bleeding in hospitalized patients starting anticoagulant therapy.

PURPOSE: To construct and test prospectively a bleeding risk index for estimating the probability of major bleeding in hospitalized patients starting long-term anticoagulant therapy. PATIENTS AND METHODS: In an inception cohort of 617 patients starting long-term anticoagulant therapy in one hospital, data were gathered retrospectively and bleeding was classified using reliable explicit criteria. We constructed a bleeding risk index by identifying and weighting independent predictors of major bleeding using a multivariate proportional-hazards model. The bleeding risk index was tested in 394 other patients prospectively identified in a second hospital. The index was compared to physicians' predictions. RESULTS: Major bleeding developed before discharge in 61 of all 1,011 patients (6%). The bleeding risk index included four independent risk factors for major in-hospital bleeding: the number of specific comorbid conditions; heparin use in patients aged 60 years or older; maximal prothrombin or partial thromboplastin time 2.0 or more times control; liver dysfunction worsening during therapy. In the testing group, the index predicted major bleeding, which occurred in 3% of 235 low-risk patients, 16% of 96 middle-risk patients, and 19% of 63 high-risk patients (p less than 0.001). The bleeding risk index performed as well as physicians' predictions, and integration of the bleeding risk index with physicians' predictions led to a classification system that was more sensitive (p = 0.03) than physicians' predictions alone. In 86% of patients with a high risk of major bleeding, we identified specific ways of improving therapy, e.g., avoiding overanticoagulation and nonsteroidal anti-inflammatory agents. CONCLUSION: The bleeding risk index provides valid estimates of the probability of major bleeding in hospitalized patients starting long-term anticoagulant therapy and complements physicians' predictions. The possibility that bleeding can be prevented in high-risk patients warrants prospective evaluation.

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PubMed1989

The bleeding severity index: validation and comparison to other methods for classifying bleeding complications of medical therapy.

Reports of bleeding complications of medical therapy should be based on valid methods of classification, but the reproducibility of existing methods has not been tested. Therefore, we prospectively studied three methods to classify the severity of bleeding: a purely subjective implicit method, a previously published explicit method using brief criteria, and the bleeding severity index, which is a new explicit method using detailed criteria about the amount, rate, and consequences of bleeding. Three physicians independently reviewed abstracts of 168 patients treated with anticoagulants. The proportion of cases classified as major bleeding varied widely when the implicit method was used (2, 14 and 39%), less when the old explicit method was used (28, 40 and 47%), and not at all when the new bleeding severity index was used (20, 20 and 20%). Intraobserver agreement was excellent for both explicit methods (kappa greater than or equal to 0.95). However, interobserver agreement was better for the bleeding severity index (kappa = 0.87) than for the old explicit method (kappa = 0.69) or the implicit method (kappa = 0.39). We conclude that the classification of bleeding complications of medical therapy depends on the method used. In comparison to older methods, the bleeding severity index is highly reproducible and should be tested more widely to determine whether it can be applied to the burgeoning clinical research in anticoagulation and thrombolysis.

Anticoagulants↗

PubMed1989

Bleeding in outpatients treated with warfarin: relation to the prothrombin time and important remediable lesions.

PURPOSE: To determine the relation of bleeding to prothrombin times and important remediable lesions in outpatients treated with warfarin. PATIENTS AND METHODS: An inception cohort of 565 patients starting outpatient therapy with warfarin on discharge from a university hospital was assembled. Detailed records of outpatient prothrombin times were obtained for 103 of 130 case subjects with major or minor bleeding and for 117 control patients without bleeding. A nested case-control design was used to evaluate the association of bleeding with temporally related prothrombin times; odds ratios were estimated using multivariate logistic regression analysis to control for known predictors of major bleeding. The relation of bleeding to important remediable lesions was determined in all 130 cases of bleeding. RESULTS: For each 1.0 increase in the prothrombin time-to-control ratio, the odds ratio for major bleeding during the week after a prothrombin time measurement increased 80%; the odds ratio for minor bleeding increased 50%. These odds ratios were lower during the first month of therapy and higher thereafter. Bleeding was related to important remediable lesions in 49 of 130 cases (38%), but these lesions were unknown before bleeding in only 22 cases (17%). The mean prothrombin time rose sharply at the time of bleeding in patients without important remediable lesions, but not in patients with lesions. New, previously unknown lesions (including nine malignancies) were discovered in 20 of 59 case subjects (34%) with gastrointestinal bleeding or hematuria, but in only two of 71 case subjects (3%) with other bleeding (p less than 0.001). CONCLUSION: Our results provide a valid quantitative basis for estimating the odds of bleeding in relation to the prothrombin time and the yield of diagnostic evaluation in patients with bleeding.

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