Bleeding assessment tools to predict von Willebrand disease: Utility of individual bleeding symptoms.

BACKGROUND: Bleeding assessment is part of the diagnostic workup of von Willebrand disease (VWD). Bleeding assessment tools (BATs) have standardized obtaining this information but have been criticized because they are time consuming. OBJECTIVE: To use our legacy data to determine which questions from BATs are the strongest predictors of a VWD diagnosis. PATIENTS/METHODS: Bleeding score data from 3 different BATs were used. Patients aged <12 years were excluded. Questions on BATs relate to different bleeding symptoms, and each symptom is scored by severity. Scores for each symptom were sorted based on whether they indicated clinically significant bleeding, and nonsignificant scores were set as the reference category. Multivariable logistic regression was used to determine the symptoms that were the strongest predictors of a laboratory-confirmed VWD diagnosis. RESULTS: A total of 927 participants were included; 144 (16%) were patients with VWD, and 783 (84%) were healthy controls. The top 3 symptoms for which a clinically significant positive response increased the likelihood of VWD were hemarthrosis (odds ratio [OR], 19.2; 95% confidence interval [CI], 3.7-100.4), postsurgical bleeding (OR, 15.2; 95% CI, 5.9-38.9), and menorrhagia (OR, 10.3; 95% CI, 4.9-21.9). With each increase in number of bleeding symptom categories with clinically significant scores, subjects had a stepwise increase in odds of a VWD diagnosis. CONCLUSIONS: Our results suggest that most of the bleeding symptoms on BATs are significant predictors of VWD, and there is value in assessing multiple bleeding symptoms when eliciting a bleeding history. Certain bleeding symptoms are more useful predictors than others. Future BAT revisions may consider adding a relative weighting to each symptom.

Theories of blood coagulation.

Although the concept of the coagulation cascade represented a significant advance in the understanding of coagulation and served for many years as a useful model, more recent clinical and experimental observations demonstrate that the cascade/waterfall hypothesis does not fully and completely reflect the events of hemostasis in vivo. The goal of this article is to review the evolution of the theories of coagulation and their proposed models to serve as a tool when reviewing the research and practice literature that was published in the context of these different theories over time.

Genetics of von Willebrand disease type 1.

The most common form of von Willebrand disease (VWD) is reported to be type 1, accounting for as much as 80% of reported cases. With prevalence estimates as high as 1.6% in the general population, upwards of 4.5 million Americans may be affected. Unfortunately, VWD type 1 is also the most difficult type to diagnose. Despite the continuing progress in defining the genetic lesions responsible for VWD types 2 and 3, identification of the genetic determinants of VWD type 1 remains elusive. Herein the phenomenon known as VWD is summarized, the challenges associated with the diagnosis of type 1 VWD are described, and the role of genetic research in meeting these challenges is explored. The authors identify key gaps in the current genetics literature and suggest new avenues for future research. Lastly, they explore the role of nurses in this research and clinical endeavor. To the authors'knowledge, this review is the first to address these complex issues in nursing research.