Nimia Reyes

Assessing emerging infectious threats to blood safety for the blood disorders community.

Technologic advances in diagnostic testing, vaccinations, pathogen inactivation, and vigilant donor screening have greatly reduced the risk of transmitting pathogens through blood transfusion. Nevertheless, transfusion-related infections and fatalities continue to be reported, and emerging pathogens continue to become an increasing threat to the blood supply. This threat is even greater to patients with blood disorders, who are heavily transfused and rely on safe blood products. This article describes some of the emerging and re-emerging transfusion-transmitted pathogens that have increased in incidence in the U.S. in recent years. Peer-reviewed articles and agency websites were the sources of information. The article focuses on the treatment of hereditary blood disorders including hemophilia and thalassemia, and hereditary bone marrow failure. A coordinated approach to addressing blood safety and continued development of sensitive diagnostic testing are necessary to reduce risk in an increasingly globalized society.

Correlates of In-Hospital Deaths among Hospitalizations with Pulmonary Embolism: Findings from the 2001−2008 National Hospital Discharge Survey

Background Deep vein thrombosis and pulmonary embolism (PE) are responsible for substantial mortality, morbidity, and impaired health-related quality of life. The aim of this study was to evaluate the correlates of in-hospital deaths among hospitalizations with a diagnosis of PE in the United States. Methods By using data from the 2001−2008 National Hospital Discharge Survey, we assessed the correlates of in-hospital deaths among 14,721 hospitalizations with a diagnosis of PE and among subgroups stratified by age, sex, race, days of hospital stay, type of admission, cancer, pneumonia, and fractures. We produced adjusted rate ratios (aRR) and 95% confidence intervals using log-linear multivariate regression models. Results Regardless of the listing position of diagnostic codes, we observed an increased likelihood of in-hospital death in subgroups of hospitalizations with ages 50 years and older (aRR = 1.82−8.48), less than 7 days of hospital stay (aRR = 1.43−1.57), cancer (aRR = 2.10−2.28), pneumonia (aRR = 1.79−2.20), or fractures (aRR = 2.18) (except for first-listed PE), when compared to the reference groups with ages 1−49 years, 7 days or more of hospital stay, without cancer, pneumonia, or fractures while adjusting for covariates. In addition, we observed an increased likelihood of in-hospital death for first-listed PE in hospitalizations of women, when compared to those of men (aRR = 1.45). Conclusions The results of this study provide support for identifying, developing, and implementing effective, evidence-based clinical assessment and management strategies to reduce PE-related morbidity and mortality among hospitalized PE patients who may have concurrent health conditions including cancer, pneumonia, and fractures.

Using multiple sources of data for surveillance of postoperative venous thromboembolism among surgical patients treated in Department of Veterans Affairs hospitals, 2005-2010

BACKGROUND There are limitations to using administrative data to identify postoperative venous thromboembolism (VTE). We used a novel approach to quantify postoperative VTE events among Department of Veterans Affairs (VA) surgical patients during 2005-2010. METHODS We used VA administrative data to exclude patients with VTE during 12 months prior to surgery. We identified probable postoperative VTE events within 30 and 90 days post-surgery in three settings: 1) pre-discharge inpatient, using a VTE diagnosis code and a pharmacy record for anticoagulation; 2) post-discharge inpatient, using a VTE diagnosis code followed by a pharmacy record for anticoagulation within 7 days; and 3) outpatient, using a VTE diagnosis code and either anticoagulation or a therapeutic procedure code with natural language processing (NLP) to confirm acute VTE in clinical notes. RESULTS Among 468,515 surgeries without prior VTE, probable VTEs were documented within 30 and 90 days in 3,931 (0.8%) and 5,904 (1.3%), respectively. Of probable VTEs within 30 or 90 days post-surgery, 47.8% and 62.9%, respectively, were diagnosed post-discharge. Among post-discharge VTE diagnoses, 86% resulted in a VA hospital readmission. Fewer than 25% of outpatient records with both VTE diagnoses and anticoagulation prescriptions were confirmed by NLP as acute VTE events. CONCLUSION More than half of postoperative VTE events were diagnosed post-discharge; analyses of surgical discharge records are inadequate to identify postoperative VTE. The NLP results demonstrate that the combination of VTE diagnoses and anticoagulation prescriptions in outpatient administrative records cannot be used to validly identify postoperative VTE events.

Clustering Patterns of Comorbidities Associated with In-Hospital Death in Hospitalizations of US Adults with Venous Thromboembolism

Background: Venous thromboembolism (VTE) is a significant source of mortality, morbidity, disability, and impaired health-related quality of life in the world. Objective: We aimed to evaluate the clustering patterns and associations of 29 comorbidities with in-hospital death among adult hospitalizations with a diagnosis of VTE in the United States by analyzing data from the 2009 Nationwide Inpatient Sample. Methods: This cross-sectional study included 153,124 adult hospitalizations with a diagnosis of VTE. Adjusted rate ratios and 95% confidence intervals (CI) for in-hospital death were generated by using multivariable log-linear regression models to measure independent associations between comorbidities and in-hospital death. Results: We estimated that 44,200 in-hospital deaths occurred in 2009 among 773,273 US adult hospitalizations with a diagnosis of VTE. Subgroups of hospitalizations with comorbidities of “congestive heart failure,” “chronic pulmonary disease,” “coagulopathy,” “liver disease,” “lymphoma,” “fluid and electrolyte disorders,” “metastatic cancer,” “peripheral vascular disorders,” “pulmonary circulation disorders,” “renal failure,” “solid tumor without metastasis,” or “weight loss” were positively and independently associated with 1.07 (95% CI: 1.02-1.12 ) to 2.06 (95% CI: 1.97-2.16) times increased likelihoods of in-hospital death, when compared to those without the corresponding comorbidities. The clustering patterns of these comorbidities by 4 disease categories (i.e., “cancer,” “cardiovascular/respiratory/blood,” “gastrointestinal/urologic,” and “nutritional/bodyweight”) were associated with 2.74 to 10.28 times increased likelihoods of in-hospital death, as compared to hospitalizations without any of these comorbidities. The overall increase in the cumulative number of comorbidities corresponded to significantly elevated risks (P-trend<0.01) for in-hospital death among hospitalizations with a diagnosis of VTE. Conclusion: The presence of multiple comorbidities is ubiquitous among hospitalizations of adults with VTE and among in-hospital deaths with VTE in the United States. The findings of our study further suggest that, among hospitalizations of adults with VTE, the presence of certain comorbidities or clustering of these comorbidities significantly elevates the risk of in-hospital death.

Hospitalizations of Adults ≥60 Years of Age With Venous Thromboembolism

We assessed the rates, trends, and factors associated with venous thromboembolism (VTE) diagnosis among hospitalizations of adults ≥60 years of age during the period 2001 to 2010. Data from the National Hospital Discharge Survey were used for this study. During the period 2001 to 2010, the estimated annual number of hospitalizations in which a VTE diagnosis was recorded, among adults ≥ 60 years of age, ranged from approximately 2 70 000 in 2001 to 4 23 000 in 2010. The rate of such hospitalizations per 1 00 000 US population ≥60 years of age ranged from 581 in 2001 to 739 in 2010. During the period 2001 to 2004, there was a significant increasing trend in the rate of hospitalizations with VTE among women ≥60 years of age. The factors positively associated with an increased risk of VTE diagnosis were female sex, summer and autumn seasons (compared with spring), venous catheterization, cancer, and greater length of hospital stay.

The design and implementation of a new surveillance system for venous thromboembolism using combined active and passive methods

Estimates of venous thromboembolism (VTE) incidence in the United States are limited by lack of a national surveillance system. We implemented a population-based surveillance system in Oklahoma County, OK, for April 1, 2012 to March 31, 2014, to estimate the incidences of first-time and recurrent VTE events, VTE-related mortality, and the proportion of case patients with provoked versus unprovoked VTE. The Commissioner of Health made VTE a reportable condition and delegated surveillance-related responsibilities to the University of Oklahoma, College of Public Health. The surveillance system included active and passive methods. Active surveillance involved reviewing imaging studies (such as chest computed tomography and compression ultrasounds) from all inpatient and outpatient facilities. Interrater agreement between surveillance officers collecting data was assessed using κ. Passive surveillance used International Classification of Disease, Ninth Revision (ICD-9) codes from hospital discharge data to identify cases. The sensitivity and specificity of various ICD-9-based case definitions will be assessed by comparison with cases identified through active surveillance. As of February 1, 2015, we screened 54,494 (99.5%) of the imaging studies and identified 2,725 case patients, of which 91.6% were from inpatient facilities, and 8.4% were from outpatient facilities. Agreement between surveillance officers was high (κ ≥0.61 for 93.2% of variables). Agreement for the diagnosis of pulmonary embolism and diagnosis of deep vein thrombosis was κ = 0.92 (95% CI 0.74-1.00) and κ = 0.89 (95% CI 0.71-1.00), respectively. This surveillance system will provide data on the accuracy of ICD-9-based case definitions for surveillance of VTE events and help the Centers for Disease Control and Prevention develop a national VTE surveillance system.

Public Health Surveillance of Nonmalignant Blood Disorders

Nonmalignant blood disorders currently affect millions of Americans, and their prevalence is expected to grow over the next several decades. This is owing to improvements in treatment leading to increased life expectancy of people with hereditary conditions, like sickle cell disease and hemophilia, but also the rising occurrence of risk factors for venous thromboembolism. The lack of adequate surveillance systems to monitor these conditions and their associated health indicators is a significant barrier to successfully assess, inform, and measure prevention efforts and progress toward national health goals. CDC is strengthening surveillance activities for blood disorders by improving and developing new methods that are tailored to best capture and monitor the epidemiologic characteristics unique to each disorder. These activities will provide a robust evidence base for public health action to improve the health of patients affected by or at risk for these disorders.