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The association between thromboembolic events (TE) and COVID-19 infection is not completely understood at the population level in the United States. We examined their association using a large US healthcare database. We analyzed data from the Premier Healthcare Database Special COVID-19 Release and conducted a case-control study. The study population consisted of men and non-pregnant women aged ≥ 18 years with (cases) or without (controls) an inpatient ICD-10-CM diagnosis of TE between 3/1/2020 and 6/30/2021. Using multivariable logistic regression, we assessed the association between TE occurrence and COVID-19 diagnosis, adjusting for demographic factors and comorbidities. Among 227,343 cases, 15.2% had a concurrent or prior COVID-19 diagnosis within 30 days of their index TE. Multivariable regression analysis showed a statistically significant association between a COVID-19 diagnosis and TE among cases when compared to controls (adjusted odds ratio [aOR] 1.75, 95% CI 1.72-1.78). The association was more substantial if a COVID-19 diagnosis occurred 1-30 days prior to index hospitalization (aOR 3.00, 95% CI 2.88-3.13) compared to the same encounter as the index hospitalization. Our findings suggest an increased risk of TE among persons within 30 days of being diagnosed COVID-19, highlighting the need for careful consideration of the thrombotic risk among COVID-19 patients, particularly during the first month following diagnosis.

Sickle cell disease (SCD) is associated with increased risk of poor health outcomes from respiratory infections, including COVID-19 illness. We used US death data to investigate changes in SCD-related mortality before and during the COVID-19 pandemic. We estimated annual age- and quarter-adjusted SCD-related mortality rates for 2014-2020. We estimated the number of excess deaths in 2020 compared with 2019 using the standardized mortality ratio (SMR). We found 1023 SCD-related deaths reported in the United States during 2020, of which 86 (8.4%) were associated with COVID-19. SCD-related deaths, both associated and not associated with COVID-19, occurred most frequently among adults aged 25-59 years. The SCD-related mortality rate changed

Sickle cell disease (SCD), a group of inherited blood cell disorders that primarily affects Black or African American persons, is associated with severe complications and a20-year reduction in life expectancy. In 2014, an expert panel convened by the National Heart, Lung, and Blood Institute issued recommendations to prevent or reduce complications in children and adolescents with the most severe SCD subtypes, known as sickle cell anemia (SCA); recommendations included 1) annual screening of children and adolescents aged 2-16 years with transcranial Doppler (TCD) ultrasound to identify those at risk for stroke and 2) offering hydroxyurea therapy to children and adolescents aged ≥9 months to reduce the risk for several life-threatening complications.Data from the IBM MarketScan Multi-State Medicaid Database were analyzed. TCD screening and hydroxyurea use were examined for 3,352 children and adolescents with SCA aged 2-16 years and continuously enrolled in Medicaid during 2019. Percentage change during 2014-2019 and variation by health subgroups were assessed. Analyses were stratified by age.During 2014-2019, TCD screening increased 27% among children and adolescents aged 10-16 years; hydroxyurea use increased 27% among children aged 2-9 years and 23% among children and adolescents aged 10-16 years. However, in 2019, only 47% and 38% of children and adolescents aged 2-9 and 10-16 years, respectively, had received TCD screening and 38% and 53% of children and adolescents aged 2-9 years and 10-16 years, respectively, used hydroxyurea. For both prevention strategies, usage was highest among children and adolescents with high levels of health care utilization and evidence of previous complications indicative of severe disease.Despite increases since 2014, TCD screening and hydroxyurea use remain low among children and adolescents with SCA. Health care providers should implement quality care strategies within their clinics and partner with patients, families, and community-based organizations to address barriers to delivering and receiving recommended care.

Study objective We provide an updated assessment of trends in sickle cell disease (SCD)–related mortality, a significant source of mortality in the United States among black persons, using 1979 to 2017 US mortality data. Methods SCD-related deaths were identified with International Classification of Diseases codes. Because SCD-related death is rare in other races, the analysis focused on black decedents. Age-specific and average annual SCD-related death rates were calculated. Causes of death codes were categorized into 20 groups relevant to SCD outcomes. SCD-related deaths were compared with non–SCD-related deaths after matching on race, sex, age group, and year of death. Results There were 25,665 SCD-related deaths reported among blacks in the United States from 1979 through 2017. During that period, the annual SCD-related death rate declined in children and increased in adults, and the median age at death increased from 28 to 43 years. Acute causes of death, such as infection and cerebrovascular complications, were more common in younger age groups. Chronic complications were more common in adults. SCD-related deaths were more likely to be related to acute cardiac, pulmonary, and cerebrovascular complications; acute infections; and chronic cardiac and pulmonary complications and renal disorders; and less likely to be related to drug overdose and chronic infections than non–SCD-related deaths. Conclusion These data indicate SCD-related deaths are now more likely to be related to chronic complications of the disease than to acute complications. More research regarding prevention and treatment of chronic complications of SCD is necessary because persons with SCD are living longer.

INTRODUCTION: The major complication of protein replacement therapy for haemophilia A is the development of anti-FVIII antibodies or inhibitors that occur in 25%−30% of persons with severe haemophilia A. Alternative therapeutics such as bypassing agents or immune tolerance induction protocols have additional challenges and are not always effective. AIM: Assemble a National Heart, Lung and Blood Institute (NHLBI) State of the Science (SOS) Workshop to generate a national blueprint for research on inhibitors to solve the problem of FVIII immunogenicity. METHODS: An Executive Steering Committee was formed in October 2017 to establish the scientific focus and Scientific Working Groups for the SOS Workshop in May 2018. Four working groups were assembled to address scientific priorities in basic, translational and clinical research on inhibitors. RESULTS: Working Group 1 was charged with determining the scientific priorities for clinical trials to include the integration of non-intravenous, non-factor therapeutics including gene therapy into the standard of care for people with haemophilia A with inhibitors. Working Group 2 established the scientific priorities for 21st-century data science and biospecimen collection for observational inhibitor cohort studies. The scientific priorities for acquiring an actionable understanding of FVIII immunogenicity and the immunology of the host response and FVIII tolerance were developed by Working Group 3. Working Group 4 designed prospective pregnancy/birth cohorts to study FVIII immunogenicity, inhibitor development and eradication. CONCLUSION: The NHLBI SOS Workshop generated a focused summary of scientific priorities and implementation strategies to overcome the challenges of eradicating and preventing inhibitors in haemophilia A.

Problem/Condition Hemophilia is an X-linked genetic disorder that primarily affects males and results in deficiencies in blood-clotting proteins. Hemophilia A is a deficiency in factor VIII, and hemophilia B is a deficiency in factor IX. Approximately one in 5,000 males are born with hemophilia, and hemophilia A is about four times as common as hemophilia B. Both disorders are characterized by spontaneous internal bleeding and excessive bleeding after injuries or surgery. Hemophilia can lead to repeated bleeding into the joints and associated chronic joint disease, neurologic damage, damage to other organ systems, and death. Although no precise national U.S. prevalence estimates for hemophilia exist because of the difficulty identifying cases among persons who receive care from various types of health care providers, two previous state-based studies estimated hemophilia prevalence at 13.4 and 19.4 per 100,000 males. In addition, these studies showed that 67% and 82% of persons with hemophilia received care in a federally funded hemophilia treatment center (HTC), and 86% and 94% of those with the most severe cases of hemophilia (i.e., those with the lowest levels of clotting factor activity in the circulating blood) received care in a federally funded HTC. As of January 2020, the United States had 144 HTCs. Period Covered 1998–2019. Description of the System Surveillance for hemophilia, which is a complex, chronic condition, is challenging because of its low prevalence, the difficulty in ascertaining cases uniformly, and the challenges in routinely characterizing and tracking associated health complications. Over time, two systems involving many stakeholders have been used to conduct ongoing hemophilia surveillance. During 1998–2011, CDC and the HTCs collaborated to establish the Universal Data Collection (UDC) surveillance system. The purposes of the UDC surveillance system were to monitor human immunodeficiency virus (HIV) and bloodborne viral hepatitis in persons with hemophilia, thereby tracking blood safety, and to track the prevalence of and trends in complications associated with hemophilia. HTC staff collected clinical data and blood specimens from UDC participants and submitted them to CDC. CDC tested specimens for viral hepatitis and HIV. In 2011, the UDC surveillance system was replaced by a new hemophilia surveillance system called Community Counts. CDC and the HTCs established Community Counts to expand laboratory testing and the collection of clinical data to better identify and track emerging health issues in persons with hemophilia. Results This report is the first comprehensive summary of CDC’s hemophilia surveillance program, which comprises both UDC and Community Counts. Data generated from these surveillance systems have been used in the development of public health and clinical guidelines and practices to improve the safety of U.S. blood products and either prevent hemophilia-related complications or identify complications early. Several factors have played a role in the effectiveness of the UDC and Community Counts systems, including 1) a stable data collection design that was developed and is continually reviewed in close partnership with HTC regional leaders and providers to ensure surveillance activities are focused on maximizing the scientific and clinical impact; 2) flexibility to respond to emerging health priorities through periodic updates to data collection elements and special studies; 3) high data quality for many clinical indicators and state-of-the-art laboratory testing methods for hemophilia treatment product inhibitors (developed and refined in part based on CDC research); 4) timely data and specimen collection and submission, laboratory specimen testing, analysis, and reporting; and 5) the largest and most representative sample of persons with hemophilia in the United States and one of the largest and most comprehensive data collection systems on hemophilia worldwide. Interpretation CDC has successfully developed, implemented, and maintained a surveillance system for hemophilia. The program can serve as an example of how to conduct surveillance for a complex chronic disease by involving stakeholders, improving and building new infrastructure, expanding data collection (e.g., new diagnostic assays), providing testing guidance, establishing a registry with specimen collection, and integrating laboratory findings in clinical practice for the individual patient. Public Health Action Hemophilia is associated with substantial lifelong morbidity, excess premature deaths, and extensive health care needs throughout life. Through monitoring data from Community Counts, CDC will continue to characterize the benefits and adverse events associated with existing or new hemophilia treatment products, thereby contributing to maximizing the health and longevity of persons with hemophilia.

Aim: The study objectives were to investigate the association between selected CYP2C9 and VKORC1 single nucleotide polymorphisms with serious bleeding or thrombotic risk, and to estimate mean daily maintenance dose of warfarin and international normalized ratio measurements among Blacks receiving warfarin anticoagulation. Methods: We conducted a retrospective cohort study among 230 Black adults receiving warfarin for a minimum of three consecutive months with a confirmed date of first dosage. Results: A lower mean daily maintenance dosage of warfarin was required to maintain an international normalized ratio measurement within the therapeutic range among Blacks with the VKORC1-1639G>A variant alleles ([G/A vs G/G, p = 0.02], [A/A vs G/A, p = 0.008] and [A/A vs G/G, p = 0.001]). Conclusion: Data indicated that VKORC1-1639A variant allele influenced warfarin daily maintenance dosage among our small, likely admixed Black patient population.

In the U.S., deaths due to pulmonary embolism (PE) account for 9.2% of all pregnancy-related deaths or approximately 1.5 deaths per 100,000 live births. Maternal deaths and maternal morbidity due to PE are more common among women who deliver by cesarean section. In the past decade, the clinical community has increasingly adopted venous thromboembolism (VTE) guidelines and thromboprophylaxis recommendations for pregnant women. Although deep vein thrombosis rates have decreased during this time-period, PE rates have remained relatively unchanged in pregnancy hospitalizations and as a cause of maternal mortality. Changes in the health profile of women who become pregnant, particularly due to maternal age and co-morbidities, needs more attention to better understand the impact of VTE risk during pregnancy and the postpartum period.

No study has examined how the relationship between polycystic ovary syndrome (PCOS) and atherosclerotic cardiovascular diseases (aCVD), of ischemic stroke (ISCH), acute myocardial infarction (AMI), and peripheral vascular disease (PAD), differ in the presence of venous thromboembolism (VTE).We performed a cross-sectional analysis using Truven Health Analytics MarketScan® Commercial databases from 2004-2011. The association between women aged 18-64 years with and without PCOS, and aCVD was assessed using VTE-stratified multivariable logistic regression models.Overall, women with PCOS were more likely to have aCVD, (aOR, 1.27; 95% CI, 1.10-1.46) especially ISCH (aOR, 1.56; 95% CI, 1.30-1.88), than women without PCOS. When stratified by VTE status, women with PCOS and a VTE diagnosis had a decreased odds of having any aCVD (aOR 0.67; 95% CI, 0.46-0.98), and VTE diagnosis more often preceded the occurrence of ISCH and AMI among women with PCOS compared with women without PCOS.Overall, women with PCOS were more likely to have aCVD, with stroke being the most prevalent manifestation. Although VTE often occurred before any aCVD, it appeared to have an inverse association with the development of ISCH, AMI, and PAD among women with PCOS, suggesting that aggressively treating VTE or aCVD early may limit the chances of developing the other thrombogenic condition among women with PCOS.

Objective This study assessed the risk of venous thromboembolism (VTE) among privately insured adults in the U.S. with one or more of the following autoimmune diseases: autoimmune hemolytic anemia (AIHA), immune thrombocytopenic purpura (ITP), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE). Materials and Methods Using the Truven Health MarketScan® Databases, patients 18–64 years of age with a diagnosis of AIHA, ITP, RA, or SLE in 2007 and a sex and age-group matched comparison group of enrollees were followed up through 2010 to identify VTE events. Survival curve and Cox proportional hazards analyses were conducted to assess differences between groups. Results Among patients with AIHA, ITP, RA, or SLE, or > 1 of these diseases, the risk of at least one VTE event was 19.74, 7.72, 4.90, 9.89, and 13.35 per 1,000 person-years, respectively; among the comparison group, the risk was 1.91 per 1,000 person-years. The adjusted hazard ratios (aHRs) for VTE among patients with AIHA, ITP, RA, or SLE, or > 1 of these diseases (when compared with the comparison group) tended to decline over follow-up time; at 1 year, the aHRs were 6.30 (95% confidence interval [CI]: 4.44–8.94), 2.95 (95% CI: 2.18–4.00), 2.13 (95% CI: 1.89–2.40), 4.68 (95% CI: 4.10–5.33), and 5.11 (95% CI: 4.26–6.14), respectively. Conclusion Having AIHA, ITP, RA, or SLE, or > 1 of these diseases was associated with an increased likelihood of a VTE event. More research is necessary to develop better understanding of VTE occurrence among people with autoimmune diseases.

Essentials Minor abundance plasma lipids, eg, glucosylceramide, can modulate blood coagulation reactions This lipid was measured in plasmas of 1 myocardial infarction and 2 venous thrombosis populations Low plasma glucosylceramide levels were found in each population compared to matched controls Low plasma glucosylceramide levels are associated with venous and arterial thrombosis Background One previous pilot study suggested the association of low plasma glucosylceramide (GlcCer) levels with venous thrombosis (VTE) risk. Objective We aimed to confirm and evaluate the association of low plasma GlcCer levels with VTE and myocardial infarction (MI) occurrence, respectively. Patients and Methods We evaluated the association of GlcCer in two independent case-control studies of Caucasian VTE populations (N=210 and 636) and one case-control study of Caucasian MI patients (N=345). Result Plasma GlcCer levels in VTE patients were lower compared to controls in two independent VTE populations (5.0 vs 5.8 μg/mL, P=.003 for the Scripps registry, and 5.6 vs 6.0 μg/mL, P=.001 for the Valencia registry, respectively). A low plasma GlcCer level (below tenth percentile of controls) was associated with increased VTE occurrence (odds ratio [OR]=3.7 [95% CI, 1.8-7.9] for Scripps registry and OR=2.1 [95% CI, 1.3-3.3] for Valencia registry, respectively). For the MI study, the median GlcCer plasma level was lower in MI patients than in controls (4.3 vs 5.6 μg/mL, P

Hemophilia B (HB) is a disorder resulting from genetic mutations in the Factor 9 gene (F9). Genotyping of HB patients is important for genetic counseling and patient management. Here we report a study of mutations identified in a large sample of HB patients in the US. Patients were enrolled through an inhibitor surveillance study at 17 hemophilia treatment centers. A total of 87 unique mutations were identified from 225 of the 226 patients, including deletions, insertions, and point mutations. Point mutations were distributed throughout the F9 gene and were found in 86% of the patients. Of these mutations, 24 were recurrent in the population, and 3 of them (c.316G>A, c.1025C>T, and c.1328T>A) accounted for 84 patients (37.1%). Haplotype analysis revealed that the high recurrence arose from a founder effect. The severity of HB was found to correlate with the type of mutation. Inhibitors developed only in severe cases with large deletions and nonsense mutations. None of the mild or moderate patients developed inhibitors. Our results provide a resource describing F9 mutations in US HB patients and confirm previous findings that patients bearing large deletions and nonsense mutations are at high risk of developing inhibitors.

Previous research has suggested autoimmune diseases are risk factors for developing venous thromboembolism (VTE). We assessed whether having diagnoses of selected autoimmune diseases associated with anti-phospholipid antibodies—autoimmune hemolytic anemia (AIHA), immune thrombocytopenic purpura (ITP), rheumatoid arthritis (RA), and systemic lupus erythematosus (SLE)—were associated with having a VTE diagnosis among US adult hospitalizations. A cross-sectional study was conducted using the 2010 Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project, Agency for Healthcare Research and Quality. VTE and autoimmune diseases were identified using International Classification of Diseases, Ninth Revision, Clinical Modification coded diagnoses information. The percentages of hospitalizations with a VTE diagnosis among all non-maternal adult hospitalizations without any of the four autoimmune diseases of interest and among those with AIHA, ITP, RA, and SLE diagnoses were 2.28, 4.46, 3.35, 2.65 and 2.77 %, respectively. The adjusted odds ratios (OR) for having a diagnosis of VTE among non-maternal adult hospitalizations with diagnoses of AIHA, ITP, RA, and SLE were 1.25 [95 % confidence interval (CI) 1.05–1.49], 1.20 (95 % CI 1.07–1.34), 1.17 (95 % CI 1.13–1.21), and 1.23 (95 % CI 1.15–1.32), respectively, when compared to those without the corresponding conditions. The adjusted OR for a diagnosis of VTE associated with a diagnosis of any of the four autoimmune diseases was 1.20 (95 % CI 1.16–1.24). The presence of a diagnosis of AIHA, ITP, RA, and SLE was associated with an increased likelihood of having a VTE diagnosis among the group of all non-maternal adult hospitalizations.

Aims: Bradykinin (BK) stimulates tissue plasminogen activator (t-PA) release from human endothelium. Although BK stimulates both nitric oxide and endothelium-derived hyperpolarizing factor (EDHF) release, the role of EDHF in t-PA release remains unexplored. This study sought to determine the mechanisms of BK-stimulated t-PA release in the forearm vasculature of healthy human subjects. Methods: In 33 healthy subjects (age 40.3 ± 1.9 years), forearm blood flow (FBF) and t-PA release were measured at rest and after intra-arterial infusions of BK (400 ng/min) and sodium nitroprusside (3.2 mg/min). Measurements were repeated after intra-arterial infusion of tetraethylammonium chloride (TEA; 1 µmol/min), fluconazole (0.4 µmol·min-1·l-1), and NG-monomethyl-L-arginine (L-NMMA, 8 µmol/min) to block nitric oxide, and their combination in separate studies. Results: BK significantly increased net t-PA release across the forearm (p < 0.0001). Fluconazole attenuated both BK-mediated vasodilation (-23.3 ± 2.7% FBF, p < 0.0001) and t-PA release (from 50.9 ± 9.0 to 21.3 ± 8.9 ng/min/100 ml, p = 0.02). TEA attenuated FBF (-14.7 ± 3.2%, p = 0.002) and abolished BK-stimulated t-PA release (from 22.9 ± 5.7 to -0.8 ± 3.6 ng/min/100 ml, p = 0.0002). L-NMMA attenuated FBF (p < 0.0001), but did not inhibit BK-induced t-PA release (nonsignificant). Conclusion: BK-stimulated t-PA release is partly due to cytochrome P450-derived epoxides and is inhibited by K+Ca channel blockade. Thus, BK stimulates both EDHF-dependent vasodilation and t-PA release.

Children with sickle cell disease (SCD) are at increased risk of illness and death from invasive pneumococcal disease (IPD). The introduction in 2000 of the 7-valent pneumococcal conjugate vaccine and penicillin prophylaxis for children with SCD has greatly reduced the incidence of IPD in this population. However, a recent report suggested an increase in cases of IPD in children with SCD.Using data from Active Bacterial Core surveillance, we analyzed trends in hospitalizations, mortality and serotype among children with SCD compared with other children. We used neonatal screening data to estimate SCD population denominators for each Active Bacterial Core surveillance site.From 1998 to 2009, 3069 cases of IPD occurred among African-American children less than 18 years of age in the Active Bacterial Core surveillance catchment area. Of these, 127 (4.1%) had SCD identified by medical chart review and 185 (6.0%) had 1 or more IPD risk factors, excluding SCD. Rates of IPD among children with SCD declined by 53% (1118 vs. 530 per 100,000) whereas the overall rates among African-American children declined by 74% (54 to 14 per 100,000). For all time periods, children with SCD and IPD were more likely to be hospitalized (84%-92% vs. 31%-56%) and more likely to die (6%-17% vs. 1%-2%) than children with no risk factors.Although the rate of IPD in children with SCD has dropped dramatically since 7-valent pneumococcal conjugate vaccine introduction, the rate of IPD in children with SCD remains higher than that of the general population of African-American children, pointing to the need for more effective prevention efforts to prevent IPD in children with SCD.

Hemophilia B (HB) is caused by mutations in the human gene F9. The mutation type plays a pivotal role in genetic counseling and prediction of inhibitor development. To help the HB community understand the molecular etiology of HB, we have developed a listing of all F9 mutations that are reported to cause HB based on the literature and existing databases. The Centers for Disease Control and Prevention (CDC) Hemophilia B Mutation Project (CHBMP) mutation list is compiled in an easily accessible format of Microsoft Excel and contains 1083 unique mutations that are reported to cause HB. Each mutation is identified using Human Genome Variation Society (HGVS) nomenclature standards. The mutation types and the predicted changes in amino acids, if applicable, are also provided. Related information including the location of mutation, severity of HB, the presence of inhibitor, and original publication reference are listed as well. Therefore, our mutation list provides an easily accessible resource for genetic counselors and HB researchers to predict inhibitors. The CHBMP mutation list is freely accessible at http://www.cdc.gov/hemophiliamutations.

Higher frequencies of pregnancy complications have been reported among women with sickle cell disease (SCD) compared with those without SCD; however, past studies are limited by small sample size, narrow geographic area, and use of hospital discharge data. We compared the prevalence of maternal complications among intrapartum and postpartum women with SCD to those without SCD in a large, geographically diverse sample. Data from the 2004-2010 Truven Health MarketScan(®) Multi-State Medicaid databases were used to assess the prevalence of maternal complications among intrapartum and postpartum women 15-44 years of age with and without SCD whose race was reported as black. The comparison group of women without SCD was further divided into those with chronic conditions associated with multi-organ failure and those without chronic conditions. Multivariable log-binomial regression models were used to calculate adjusted prevalence ratios for outcomes for women with SCD compared with women in the two comparison groups. Of the 335,348 black women with a delivery during 2004-2010, 1,526 had a diagnosis of SCD (0.5 %). Compared with women without SCD who had chronic conditions, women with SCD had higher prevalence of deep vein thrombosis, pulmonary embolism, obstetric shock, pneumonia, sepsis, postpartum infection, and transfusions. SCD was also positively associated with acute renal failure, cerebrovascular disorder, respiratory distress syndrome, eclampsia, postpartum hemorrhage, preterm birth, and ventilation when compared with women without SCD and chronic conditions. Overall, women with SCD have increased prevalence of pregnancy complications, even when compared with a group of women with similar risk for multi-organ failure.

Genotyping efforts in hemophilia A (HA) populations in many countries have identified large numbers of unique mutations in the Factor VIII gene (F8). To assist HA researchers conducting genotyping analyses, we have developed a listing of F8 mutations including those listed in existing locus-specific databases as well as those identified in patient populations and reported in the literature. Each mutation was reviewed and uniquely identified using Human Genome Variation Society (HGVS) nomenclature standards for coding DNA and predicted protein changes as well as traditional nomenclature based on the mature, processed protein. Listings also include the associated hemophilia severity classified by International Society of Thrombosis and Haemostasis (ISTH) criteria, associations of the mutations with inhibitors, and reference information. The mutation list currently contains 2,537 unique mutations known to cause HA. HA severity caused by the mutation is available for 2,022 mutations (80%) and information on inhibitors is available for 1,816 mutations (72%). The CDC Hemophilia A Mutation Project (CHAMP) Mutation List is available at http://www.cdc.gov/hemophiliamutations for download and search and will be updated quarterly based on periodic literature reviews and submitted reports.

Venous thromboembolism (VTE) affects as many as 1 in 1000 individuals in the United States. Although Blacks are disproportionately affected by VTE, few genetic risk factors have been identified in this population. The inducible heme oxygenase-1 (HMOX1) gene encodes a key cytoprotective enzyme with anti-inflammatory, antioxidant and anticoagulant activity acting in the vascular system. A (GT)(n) microsatellite located in the promoter of the HMOX1 gene influences the level of response.Using the Genetic Attributes and Thrombosis Epidemiology (GATE) study, we examined the association between HMOX1 repeat length and VTE events in 883 Black and 927 White patients and matched controls. We found no association between HMOX1 genotypes and VTE in Whites. However, in Black patients, carrying two long (L) alleles (≥ 34 repeats) was significantly associated with provoked (odds ratio (OR) 1.86, 95% confidence interval (CI): 1.19-2.90) or recurrent (OR 3.13, 95% CI: 1.77-5.53) VTE events.We have demonstrated for the first time an association between genetic variation in HMOX1, and VTE in Blacks. Our results support a key role for the heme oxygenase system in protecting patients at increased risk for thrombosis and suggest a potential mechanism for targeted screening and intervention.

OBJECTIVE: Information on trends in venous thromboembolism (VTE) in US children is scant and inconsistent. We assessed national trends in VTE-associated pediatric hospitalizations. METHODS: All nonroutine newborn hospitalizations for children 0 to 17 years of age in the 1994–2009 Nationwide Inpatient Samples were included; routine newborn discharges were excluded. VTE diagnoses were identified by using the International Classification of Diseases, Ninth Revision, Clinical Modification codes. Variance weighted least square regression was used to assess trends in patient characteristics and rates of hospitalization per 100 000 population

Silent cerebral infarct (SCI) is the most commonly recognized cause of neurological injury in sickle cell anaemia (SCA). We tested the hypothesis that magnetic resonance angiography (MRA)-defined vasculopathy is associated with SCI. Furthermore, we examined genetic variations in glucose-6-phosphate dehydrogenase (G6PD) and HBA (α-globin) genes to determine their association with intracranial vasculopathy in children with SCA. Magnetic resonance imaging (MRI) of the brain and MRA of the cerebral vasculature were available in 516 paediatric patients with SCA, enrolled in the Silent Infarct Transfusion (SIT) Trial. All patients were screened for G6PD mutations and HBA deletions. SCI were present in 41·5% (214 of 516) of SIT Trial children. The frequency of intracranial vasculopathy with and without SCI was 15·9% and 6·3%, respectively (P 0·001). Using a multivariable logistic regression model, only the presence of a SCI was associated with increased odds of vasculopathy (P = 0·0007, odds ratio (OR) 2·84; 95% Confidence Interval (CI) = 1·55-5·21). Among male children with SCA, G6PD status was associated with vasculopathy (P = 0·04, OR 2·78; 95% CI = 1·04-7·42), while no significant association was noted for HBA deletions. Intracranial vasculopathy was observed in a minority of children with SCA, and when present, was associated with G6PD status in males and SCI.

Introduction We used health insurance claims data from large samples of Medicaid-enrolled and privately insured children to identify children with venous thromboembolism (VTE) and to assess their use of health services and associated expenditures during 2009. Materials and Methods Data from the 2009 Thomson Reuters MarketScan® Commercial Database and Multi-State Medicaid database were used to estimate annual expenditures for children 1–17 years of age with VTE. Generalized linear models were used to calculate adjusted annual expenditures for Medicaid-enrolled and privately insured children with VTE, controlling for age, sex, type of health plan, VTE classification (deep vein thrombosis and/or pulmonary embolism), and type of VTE event (idiopathic or secondary) and race (Medicaid only) or region (Commercial only). Results During 2009, Medicaid-enrolled and privately insured children with VTE had an average of 1–2 inpatient admissions and 8–10 non-emergency department visits. Unadjusted mean total expenditures were similar for Medicaid-enrolled and privately insured children with VTE, $105,359 and $87,767, respectively. Adjusted mean expenditures for children with secondary VTE were five times higher than for children with idiopathic VTE. Conclusions Given the high frequency of secondary VTE in children, most of the associated expenditures may be due to other health conditions. However, children who develop a VTE incur substantial costs of care, even in the absence of related conditions. Additional research is needed to evaluate the long term outcomes for children with VTE including rates of readmission, complications, and the impact of co-morbid conditions.

Both genetic and treatment-related risk factors contribute to the development of inhibitors in haemophilia. An inhibitor surveillance system piloted at 12 US sites has the goal of assessing risk factors through prospective data collection. This report examines the relationship of genotype and race/ethnicity to history of inhibitor in a large cohort of US haemophilia patients. Mutation analysis was performed on 676 haemophilia A (HA) and 153 haemophilia B (HB) patients by sequencing, Multiplex Ligation-dependent Probe Amplification, and PCR for inversions in F8 introns 22 (inv22) and 1 (inv1). Two HB patients with deletions had history of inhibitor. In severe HA, frequency of history of inhibitor was: large deletion 57.1%, splice site 35.7%, inv22 26.8%, nonsense 24.5%, frameshift 12.9%, inv1 11.1% and missense 9.5%. In HA, 19.6% of 321 White non-Hispanics (Whites), 37.1% of 35 Black non-Hispanics (Blacks) and 46.9% of 32 Hispanics had history of inhibitor (P = 0.0003). Mutation types and novel mutation rates were similar across ethnicities. When F8 haplotypes were constructed, Whites and Hispanics showed only H1 and H2. Within H1, history of inhibitor was 12.4% in Whites, 40.0% in Blacks (P = 0.009) and 32.4% in Hispanics (P = 0.002). Inhibitor frequency is confirmed to vary by mutation type and race in a large US population. White patients with history of inhibitor did not exhibit rare F8 haplotypes. F8 gene analysis did not reveal a cause for the higher inhibitor frequencies in Black and Hispanic patients.

Introduction: Black Americans have been reported to have a higher incidence of venous thromboembolism (VTE) compared to white Americans. The underlying cause of this disparity is not well characterized. Protein S, protein C, and antithrombin deficiency are known risk factors for VTE. There is inconsistent data regarding racial variation on the effect of protein S, protein C, and antithrombin levels and/or deficiency and risk of VTE. Most prior studies have not included a large black study population. The aim of this investigation is to compare levels of protein C, protein S, and antithrombin between VTE cases and controls by race among enrollees in the Genetic Attributes and Thrombosis Epidemiology (GATE) study, accounting for genetic differences such as hemoglobin genotype that may contribute to differences in protein levels by race. Methods: Testing for protein S, protein C, and antithrombin deficiency was performed on a subset of participants enrolled in the GATE study, a case-control study comprised of VTE cases and controls frequency-matched on age, sex, and race (self-identified). Controls had no history of VTE and did not receive anticoagulant therapy. Antigen and activity levels in cases were measured at least one month after completion of anticoagulation therapy. A priori cutoff levels for determining deficiency status were standardized per Centers for Disease Control Hemostasis Laboratory reference ranges. Beta hemoglobin genotype was determined by either a multiplex genotyping assay or sequencing of the beta hemoglobin gene. Differences in protein levels between cases and controls were compared using the Wilcoxon rank sum test. Conditional logistic regression analysis was performed to evaluate the association between protein S, protein C, or antithrombin deficiency and VTE. Crude models were conditioned on the matching factors, and adjusted models were conditioned on the matching factors and controlled for patient characteristics found to be associated with VTE and protein S, protein C, or antithrombin deficiency. Potential effect modification was assessed using likelihood ratio tests. Results: Among 2,454 subjects enrolled in the GATE study, 1,436 subjects (63.6%) had samples available for analysis. Protein S activity and total protein S antigen levels were significantly lower among VTE cases compared to controls in both white and black participants; however, antithrombin levels were higher among VTE cases compared to controls in white participants only. (Table 1) The prevalence of protein S and protein C deficiency was higher among VTE cases compared to controls in both white and black participants in the GATE study (Table 2). The prevalence of antithrombin deficiency was similar between VTE cases compared to controls. Adjusting for the effect of family history of VTE, history of cancer, and hemoglobin genotype, the effect of protein S and protein C deficiency on odds of VTE was stronger among black participants compared to white participants (Table 2). Conclusions: The effects of protein S and protein C deficiency on the odds of being a VTE case were higher among black participants in the GATE study, controlling for confounding variables including hemoglobin genotype. While these results indicate protein S and protein C deficiency may be important contributors to disparities in VTE occurrence, additional investigations using a larger study populations and different study designs are warranted. Disclosures Patel: Daiichi Sankyo: Other: DSMB member. Payne:Bioverativ: Other: treatment product donation; Novo Nordisk: Other: treatment product donation; Shire: Other: treatment product donation; Genentech: Membership on an entity's Board of Directors or advisory committees; Bayer: Other: treatment product donation.

Introduction: The final events of the activated clotting cascade include the conversion of fibrinogen to fibrin and stabilization of the growing fibrin clot by factor XIII (FXIII). A missense variant in the alpha chain of fibrinogen, α-fibrinogen (FGA) Thr312Ala (rs6050, NM_000508.3:c.991A>G, NP_000499.1:p.[Thr331Ala]), has been previously shown to interfere with FXIII-dependent cross-linking, leading to stiffer blood clots. It is believed this pathophysiology underlies the increased risk of venous thromboembolism (VTE) associated with the variant. The Thr312Ala variant has been shown to be significantly associated with VTE among White, Non-Hispanic populations. The only investigation of the variant in a Black population (Rasmussen-Torvik et al 2007) found no significant relationship between Thr312Ala and VTE, but the authors cite the relatively small number of participants included in the analysis as a possible reason for a null finding. We investigated the association between FGA Thr312Ala and VTE in a case-control study enrolling a relatively large racially diverse study population. Methods: Conditional logistic regression was used to assess the association between FGA Thr312Ala and VTE among enrollees in the Genetic Attributes and Thrombosis Epidemiology (GATE) study, a case-control study enrolling 1,042 VTE cases and 1,213 controls with no history of VTE, frequency-matched on age, sex, and race. Crude models conditioned on the matching factors, and adjusted models conditioned on the matching factors and controlled for patient characteristics found to be associated with both case/control status and FGA Thr312Ala genotype. Among all patient characteristics evaluated, the β-fibrinogen (FGB) promoter region variant -455 G>A (rs1800790, NM_001184741.1:c.-463G>A) was the only patient characteristic associated with both case/control status and FGA Thr312Ala genotype. Potential effect modification was assessed using likelihood ratio tests. Results: Among 660 White controls and 528 White cases in the GATE study, carrying at least one FGA rs6050 G (Ala) allele was associated with increased odds of VTE compared to not carrying a G allele (odds ratio (OR) and 95% confidence interval (CI) 1.2 [1.0-1.5]) in a crude model. This association was strongest when restricting to n=205 idiopathic (unprovoked) cases, n=125 recurrent cases, or n=112 cases exhibiting both deep vein thrombosis (DVT) and pulmonary embolism (PE) (Table 1). This association was modified by obesity status, with the effect among obese enrollees being multiplicative (Table 2). In contrast, there was no association between carrying at least one FGA rs6050 G (Ala) allele and VTE among 553 Black controls and 514 Black cases in the GATE study (OR and 95% CI 1.0 [0.8-1.2]) when assessing the association among all cases (Table 1). However, the odds of VTE was higher among Black participants carrying the G allele compared to those not carrying the allele when restricting to n=103 PE only cases (OR and 95% CI 1.5 [1.0-2.4]). The association between FGA Thr312Ala and VTE did not appear to be modified by obesity status among Black participants (Table 2). Conclusions: These results indicate that the FGA Thr312Ala (rs6050, NM_000508.3:c.991A>G, NP_000499.1:p.[Thr331Ala]) polymorphism is associated with VTE among White participants in the GATE study, with the strongest effect seen in participants exhibiting both DVT and PE. However, the association among Black participants appears limited to PE, indicating further exploration of genetic risk factors for VTE in Black populations is warranted in order to better understand genetic risk factors for all types of VTE in this population. Disclosures Payne: Bayer: Other: treatment product donation; Bioverativ: Other: treatment product donation; Novo Nordisk: Other: treatment product donation; Shire: Other: treatment product donation; Genentech: Membership on an entity's Board of Directors or advisory committees. Patel:Daiichi Sankyo: Other: DSMB member.

Venous thromboembolism (VTE), defined as deep vein thrombosis, pulmonary embolism, or both, affects an estimated 300,000-600,000 individuals in the U.S. each year, causing considerable morbidity and mortality. It is a disorder that can occur in all races and ethnicities, all age groups, and both genders. With many of the known risk factors-advanced age, immobility, surgery, obesity-increasing in society, VTE is an important and growing public health problem. Recently, a marked increase has occurred in federal and national efforts to raise awareness and acknowledge the need for VTE prevention. Yet, many basic public health functions-surveillance, research, and awareness-are still needed. Learning and understanding more about the burden and causes of VTE, and raising awareness among the public and healthcare providers through a comprehensive public health approach, has enormous potential to prevent and reduce death and morbidity from deep vein thrombosis and pulmonary embolism throughout the U.S.

Among the cardiovascular diseases and after ischemic heart disease and stroke, venous thromboembolism (VTE) is the third leading cause of death in the U.S. (3). Although VTE is seen across most ethnic groups in the U.S. as well as throughout the world, the rate varies. In the U.S., American Indians/Alaskan Natives as well as Asians have been reported to have a significantly lower rate of deep vein thrombosis (DVT) and pulmonary embolism (PE) as compared to blacks and whites. In sharp conrast blacks appear to have much higher rates than whites. Although these rate differences are thought in part by some to be attributable to disparities in diagnosis and care as well as genetics, it nevertheless is important to define as well as to understand the true incidence and impact so that both public health and clinical resources can be maximally utilized. The purpose of this commentary is to review the VTE burden in the U.S. with respect to ethnicity in terms of clinical demographics and genetics with particular emphasis on blacks.

SummaryGenetic determinants of venous thromboembolism (VTE) in the African-American population are poorly characterised. It was recently shown that fibrinogen gamma gene (FGG) polymorphisms 10034C>T and 9340T>C influence VTE risk in the Caucasian population. In the African-American population these polymorphisms are common, with allele frequencies above 25%. Here we evaluated whether these and other FGG 3’-end polymorphisms were associated with VTE risk in the African-American population and aimed to replicate the association in the Caucasian population. We examined 557 Caucasian patients and 678 Caucasian controls, and 537 African-American patients and 586 African-American controls from the ‘Genetic Attributes and Thrombosis Epidemiology’ (GATE) study. In the African-American population, 10034C>T and 9340T>C marginally influenced VTE-risk, with a 20% increase in risk for 10034TT carriers and a 20% reduction in risk for 9340CC carriers. In the Caucasian population, 10034TT was associated with a 1.7-fold increase in risk, which increased to 2.1-fold for idiopathic VTE patients. 9340CC significantly reduced VTE risk approximately two-fold. In conclusion, both FGG polymorphisms 10034C>T and 9340T>C influence VTE-risk, with the strongest effects observed in the Caucasian population, confirming previous data on these polymorphisms in this population.

People with sickle cell disease have a chronically activated coagulation system and display hemostatic perturbations, but it is unknown whether they experience an increased risk of venous thromboembolism. We conducted a case–control study of venous thromboembolism that included 515 hospitalized black patients and 555 black controls obtained from medical clinics. All subjects were assayed for hemoglobin S and hemoglobin C genotypes. The prevalence of the S allele was 0.070 and 0.032 for case patients and controls, respectively (P < .001). The odds that a patient had sickle cell trait were approximately twice that of a control, indicating that the risk of venous thromboembolism is increased approximately 2-fold among blacks with sickle cell trait compared with those with the wild-type genotype (odds ratio = 1.8 with 95% confidence interval, 1.2-2.9). The odds ratio for pulmonary embolism and sickle cell trait was higher, 3.9 (2.2-6.9). The prevalence of sickle cell disease was also increased among case patients compared with controls. We conclude that sickle cell trait is a risk factor for venous thromboembolism and that the proportion of venous thromboembolism among blacks attributable to the mutation is approximately 7%.

The toll-like receptor 4 gene product (TLR4) has been implicated in the pathogen recognition response mechanism because it plays a central role in the transcriptional activation of the host defense system. Activation of TLR4 initiates an intracellular signaling cascade, via the adapter protein MyD88 (myeloid differentiation factor 88), which leads to the activation of NF-kappaB transcriptional factor, and ultimately to the induction of a pro-inflammatory response. This inflammatory response has been increasingly associated with atherosclerosis. Recent analyses on two polymorphisms of TLR4, which affect the extracellular domain of the receptor, have been shown to give rise to an attenuated innate immune defense which may contribute to disease susceptibility. We have investigated the significance of four new substitutions found by re-sequencing in the 5'-proximal promoter region of the TLR4 gene in a case-control study of acute myocardial infarction. Our results found no statistically significant association between these genetic variants and MI.

The present study describes positive and negative interference of human cytokine measurement in multiplexed bead-based immunoassays. Significant differences in measured IL-6 and TNF-α values in 30 normal human plasma samples were apparent depending on whether measurements were with a 2-plex assay or embedded in a multiplex of 8-or more cytokine antibody pairs, as well as among the kits of 3-different vendors. Sample diluents containing proprietary blocking ingredients were shown to greatly affect the outcome of measured cytokine values. Additionally, recovery of IL-6 and TNF-α from spiked samples suggests significant negative interference from either endogenous antibodies, soluble receptors or anti-cytokine antibodies in 10% and 26% of samples, respectively. While it is evident that multiplexed immunoassays hold great promise for cytokine profiling, there are still important issues needing further study. Especially needed are universally optimized sample diluents, uniformly calibrated standards with mass values, and internal assay controls, which should greatly facilitate intralaboratory accuracy and precision and interlaboratory comparisons of cytokine measurements. Possible causes of interference and remedies are discussed.

Mycoplasma pneumoniae can be divided into two main subtypes depending on the amino acid sequences of the P1 adhesin and the P65 protein, both located in the attachment organelle. Differences between these subtypes in infectivity, virulence and interaction with host cells have not been extensively studied. Using ELISA to measure released protein and real-time PCR to quantify mRNA, we have demonstrated that both M. pneumoniae subtypes significantly increased tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-8 (IL-8) at comparable levels in THP-1 cells over a 72 h period of time. However, subtype 2 induced a statistically significant increase (P

ObjectivesThe study investigated the relationship between biomarkers of oxidative stress and early atherosclerosis.BackgroundOxidative stress is an important etiologic factor in the pathogenesis of vascular disease. We hypothesized that oxidative stress would predict early atherosclerosis in a relatively healthy population.MethodsOne hundred fourteen healthy non-smokers, without known clinical atherosclerosis, had carotid intima-media thickness (IMT) measured using ultrasound. Oxidative stress was estimated by measuring plasma levels of: 1) glutathione (GSH), an important intracellular antioxidant thiol, its oxidized disulfide form (GSSG), and their redox state (EhGSH/GSSG), and 2) cysteine (Cys), an important extracellular antioxidant thiol, its oxidized disulfide form cystine (CySS), and their redox state (EhCys/CySS).ResultsThe univariate predictors of IMT were age, body mass index, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein cholesterol, high-sensitivity C-reactive protein (hs-CRP), and Framingham risk score. Intima-media thickness was also higher in males and hypertensive subjects. Among the oxidative stress markers, GSH (r = −0.39, p < 0.0001), CySS (r = 0.18, p = 0.049), and EhGSH/GSSG (r = 0.34, p < 0.0002) correlated with IMT. After adjusting for traditional risk factors and hs-CRP, only EhGSH/GSSG remained an independent predictor of IMT. EhGSH/GSSG predicted IMT in a manner that was both independent of and additive to Framingham risk score.ConclusionsGlutathione redox state (EhGSH/GSSG), an in vivo measure of intracellular oxidative stress, is an independent predictor for the presence of early atherosclerosis in an otherwise healthy population. This finding supports a role for oxidative stress in the pathogenesis of premature atherosclerosis, and its measurement may help in the early identification of asymptomatic subjects at risk of atherosclerotic disease.

a Office of Dietary Supplements, National Institutes of Health Bethesda, MD, United States b Platelet Disorder Support Association, Rockville, MD, United States c National Consumers League, Washington, DC, United States d American Medical Association, Chicago, IL, United States e American Society of Hematology, Washington, DC, United States f American Herbal Products Association, Silver Spring, MD, United States g The American Society for Clinical Nutrition, Bethesda, MD, United States h American Dietetic Association, Chicago, IL, United States i American Society of Health-System Pharmacists, Bethesda, MD, United States j Centers for Disease Control and Prevention, Atlanta, GA, United States

SummaryHaemostatic abnormalities can be detected in a portion of the women who have recurrent fetal loss. We measured factor VII coagulant activity (FVII:C) in 65 women with 3 or more fetal losses (recurrent cases), 31 women with one 2nd or 3rd trimester loss (late loss cases), and 81 women with only live births (controls). FVII:C was greater than 2 standard deviations above the mean for controls in 9 recurrent cases (13.8%) and 2 controls (2.5%) for an odds ratio of 6.35 (95% CI 1.32–30.52, p=0.012). In recurrent cases, mean levels were significantly higher than controls for FVII:C (p=0.003), FVII antigen (p=0.024), and FVIIa (p=0.001). Late loss cases had an odds ratio of 4.23 (95% CI 0.67–26.67, p=0.098) with FVII:C, FVII antigen, and FVIIa not significantly different from the controls. DNA was examined for the presence of mutations or polymorphisms in the promoter region of the FVII gene, using denaturing HPLC. Abnormal patterns were confirmed with direct sequencing. A previously reported polymorphism,–402 G>A, was found to be present in 11/14 subjects with elevated FVII:C (79%) and 43% of those with normal levels (p=0.029). FVII:C, FVII antigen and FVIIa varied significantly with genotype; however, genotype frequencies did not differ between controls and either case group. No other promoter polymorphisms were identified. This is the first report of a significant elevation of FVII in a population with recurrent fetal loss. These data suggest the need for further investigation of this potential risk factor.

BACKGROUND: To evaluate the risk of human parvovirus B19 (B19) transmission in recombinant antihemophilic factor, the seroprevalence among 798 two- to seven-year-old boys with hemophilia was compared. Also, data collected on joints were used to assess relations between B19 serostatus and joint range-of-motion (ROM) limitation. STUDY DESIGN AND METHODS: Staff at US hemophilia treatment centers collected data on product exposures and ROM of 10 joints and provided blood specimens as part of blood safety surveillance. Blood was tested for immunoglobulin G anti-B19. Associations between B19 seropositivity and treatment products and joint ROM limitations were examined in multivariate analyses. RESULTS: Compared to children who received no product, the odds of B19 seropositivity were 0.8 (p = 0.5), 1.9 (p = 0.05), and 7.6 (p < 0.001) for those children who received recombinant antihemophilic factor only, both recombinant antihemophilic factor and plasma-derived factor, and plasma-derived factor only, respectively. Children who were anti-B19 positive had an average 8° less overall ROM (p = 0.002) than those who were B19 antibody negative after adjustment for other risk factors. CONCLUSION: The risk of B19 transmission by recombinant antihemophilic factor is low. Previous B19 infection is associated with ROM limitations in very young male patients with hemophilia. Virus inactivation techniques effective against B19 and other nonenveloped viruses are needed.

OBJECTIVE—Patients with the metabolic syndrome often have abnormal levels of proinflammatory and pro-oxidative mechanisms within their vasculature. We sought to determine whether the ACE inhibitor quinapril regulates markers of oxidative stress in the metabolic syndrome. RESEARCH DESIGN AND METHODS—Forty patients with the metabolic syndrome were randomized in a double-blind manner to either the ACE inhibitor quinapril (20 mg/day) or matching placebo for 4 weeks. Serum markers of vascular oxidative stress were measured. RESULTS—After 4 weeks of therapy, serum 8-isoprostane was reduced by 12% in the quinapril group when compared with placebo (quinapril, 46.7 ± 1.0; placebo, 52.7 ± 0.9 pg/ml; P = 0.001). Erythrocyte superoxide dismutase activity increased 35% in the quinapril group when compared with placebo (quinapril, 826.3 ± 17.1; placebo, 612.3 ± 6.9 units/g Hb; P < 0.001). In addition, lag time to oxidation of LDL, a marker of oxidative stress, was increased by 48% in the quinapril group when compared with placebo (quinapril 89.2 ± 9.2 vs. placebo 60.1 ± 12.3 min; P < 0.001). Therapy with quinapril was well tolerated. CONCLUSIONS—The addition of the ACE inhibitor quinapril reduces markers of vascular oxidative stress and may attenuate the progression of the pathophysiology seen in the metabolic syndrome.

Chlamydia pneumoniae is an obligate intracellular human pathogen that causes acute respiratory diseases such as pneumonia and bronchitis. Previous studies have established that C. pneumoniae can induce cytokines in mouse and/or human cells, but little information is available on the cytokine response of respiratory epithelial cells, a first line of infection. In this study, heparin treatment of C. pneumoniae significantly reduced its ability to induce interleukin 8 (IL-8) and tumor necrosis factor alpha (TNF-α) mRNA in human lung carcinoma cells, indicating that cytadherence is an important early stimulus for induction of proinflammatory mediators. Although the IL-8, gamma interferon, and TNF-α message was consistently induced by infection of A549 cells not treated with heparin, only an elevation of IL-8 protein was detected in A549 supernatants. A549 IL-β and IL-6 mRNA and supernatant protein profiles were not significantly changed by infection. Heat or UV inactivation of C. pneumoniae only partially reduced the cytokine response, and inhibition of C. pneumoniae protein or DNA synthesis did not affect its ability to induce cytokine gene expression. To prevent stress-induced cytokine release by the A549 cells, centrifugation was not utilized for infection experiments. These experiments establish the importance of cytadherence in cytokine release by cells of respiratory epithelial origin and suggest that further work in the area of cytokine mediators is warranted to gain valuable pathogenic and therapeutic insights.

Interleukin-1beta (IL-1beta) is a major proinflammatory cytokine that is involved in many important cellular functions such as proliferation, differentiation, and activation of different cell types. Its mature form is released from the cells in response to various bacterial and viral infections, and it plays a significant role in host defense. Mycoplasma pneumoniae is a small bacterium without a cell wall that causes tracheobronchitis and atypical pneumonia in humans following attachment to respiratory epithelium, as well as extrapulmonary infections. Very little is known about the role of cytokines in pathogenesis or the response of target cells to M.pneumoniae attachment. The purpose of this study was to investigate the ability of M. pneumoniae to induce IL-1beta in human lung epithelial carcinoma A549 and in human monocytic U937 cell lines. Following M. pneumoniae infection, both IL-1beta mRNA and protein were induced in A549 cells vs. no induction in uninfected cells; however, the protein remained inside the A549 cells. Similarly, M. pneumoniae infection strongly increased mRNA and extracellular protein levels in U937 cells, which unlike A549 cells did exhibit baseline constitutive levels. De novo IL-1beta protein expression was verified by cycloheximide studies. M. pneumoniae infection did not affect constitutive caspase-1 mRNA or protein levels in either cell line. Reduced caspase-1 activity in A549 cell lysates suggests the presence of an endogenous caspase-1 inhibitory component in the A549 cells. These collective data confirm previous studies that show that M. pneumoniae is a potent inducer of cytokines following adherence to host target cells, and establish that IL-1beta release in response to M. pneumoniae infection is cell-type specific, thus emphasizing the importance of carefully considering multiple cell types in M. pneumoniae pathogenesis studies involving both immune cells and cytokine release patterns.

Recurrent venous thromboembolism (VTE) occurs infrequently following a provoked event but occurs in up to 30% of individuals following an initial unprovoked event. There is limited understanding of the biological mechanisms that predispose patients to recurrent VTE.To identify whole blood gene expression profiles that distinguished patients with clinically distinct patterns of VTE.We studied 107 patients with VTE separated into 3 groups: (1) 'low-risk' patients had one or more provoked VTE; (2) 'moderate-risk' patients had a single unprovoked VTE; (3) 'high-risk' patients had ≥2 unprovoked VTE. Each patient group was also compared to twenty-five individuals with no personal history of VTE. Total RNA from whole blood was isolated and hybridized to Illumina HT-12V4 Beadchips to assay whole genome expression.Using class prediction analysis, we distinguished high-risk patients from low-risk patients and healthy controls with good receiver operating curve characteristics (AUC=0.81 and 0.84, respectively). We also distinguished moderate-risk individuals and low-risk individuals from healthy controls with AUC's of 0.69 and 0.80, respectively. Using differential expression analysis, we identified several genes previously implicated in thrombotic disorders by genetic analyses, including SELP, KLKB1, ANXA5, and CD46. Protein levels for several of the identified genes were not significantly different between the different groups.Gene expression profiles are capable of distinguishing patients with different clinical presentations of VTE, and genes relevant to VTE risk are frequently differentially expressed in these comparisons.

Background and Purpose— The purpose of the present study was to compare the prevalences of genetic polymorphisms in persons with cryptogenic stroke with those among stroke patients with evidence of large-artery occlusive disease or an unequivocal cardioembolic source (noncryptogenic stroke). Methods— We compared the prevalences of genetic polymorphisms thought to be related to thrombi formation in young stroke patients with evidence of large-artery occlusive disease or an unequivocal cardioembolic source (noncryptogenic stroke; controls; n=79) with those in young stroke patients without such sources (cryptogenic stroke; cases; n=67). Common variations in the genes encoding factor V, prothrombin, angiotensin I–converting enzyme, 5,10-methylenetetrahydrofolate reductase, endothelial cell nitric oxide synthase, tissue plasminogen activator, plasminogen activator inhibitor–1, and fibrinogen were evaluated. We also compared the allele prevalence of these genes among all stroke patients with those among a large pool of historical controls assayed for these genes. Results— None of these genetic polymorphisms was statistically significantly related to cryptogenic stroke. With respect to a comparison of all ischemic stroke with historical controls, only the prevalence of tissue plasminogen activator D allele among stroke subjects was statistically significantly higher than that of the historical controls ( P =0.0014). Conclusions— These findings generally do not support the hypothesis that genes associated with a prothrombotic state are risk factors among a subgroup of young people with stroke of undetermined cause. Except for the D tissue plasminogen activator allele, the findings also indicated that these genetic factors are unrelated, or only weakly related, to all ischemic stroke.

Background Weight loss and sodium reduction are useful nonpharmacologic interventions in the management of hypertension. Salt sensitivity—the degree of blood pressure change in response to a change in sodium load—has been extensively explored. However, the determinants of the extent of blood pressure change after weight reduction have not been evaluated. Methods We studied the relationship of the angiotensin-converting enzyme insertion-deletion (ACE I/D) polymorphism to blood pressure change after weight loss in the Trial Of Nonpharmacologic interventions in the Elderly (TONE). We focused on the 86 overweight white hypertensive TONE participants who were randomized to weight loss only. Results A similar weight reduction was observed across all ACE genotypes, whereas a significantly greater decrease in blood pressure after weight loss was seen among participants with the DD genotype. In addition, DD participants had a higher probability of remaining normotensive for the duration of the trial. Conclusions The DD genotype may be associated with higher “weight sensitivity” in overweight white hypertensive persons, potentially through reduced activity of the renin-angiotensin and sympathetic systems after weight loss. (Am Heart J 2002;144:625-9.)