Race, ABO blood group, and venous thromboembolism risk: not black and white

A combination of strongly associated prothrombotic single nucleotide polymorphisms could efficiently predict venous thrombosis risk

Background

Venous thrombosis (VT) is multifactorial trait that contributes to the global burden of cardiovascular diseases. Although abundant single nucleotide polymorphisms (SNPs) provoke the susceptibility of an individual to VT, research has found that the five most strongly associated SNPs, namely, rs6025 (F5 Leiden), rs2066865 (FGG), rs2036914 (F11), rs8176719 (ABO), and rs1799963 (F2), play the greatest role. Association and risk prediction models are rarely established by using merely the five strongly associated SNPs. This study aims to explore the combined VT risk predictability of the five SNPs and well-known non-genetic VT risk factors such as aging and obesity in the Hungarian population.

Methods

SNPs were genotyped in the VT group (n = 298) and control group (n = 400). Associations were established using standard genetic models. Genetic risk scores (GRS) [unweighted GRS (unGRS), weighted GRS (wGRS)] were also computed. Correspondingly, the areas under the receiver operating characteristic curves (AUCs) for genetic and non-genetic risk factors were estimated to explore their VT risk predictability in the study population.

Results

rs6025 was the most prevalent VT risk allele in the Hungarian population. Its risk allele frequency was 3.52-fold higher in the VT group than that in the control group [adjusted odds ratio (AOR) = 3.52, 95% CI: 2.50-4.95]. Using all genetic models, we found that rs6025 and rs2036914 remained significantly associated with VT risk after multiple correction testing was performed. However, rs8176719 remained statistically significant only in the multiplicative (AOR = 1.33, 95% CI: 1.07-1.64) and genotypic models (AOR = 1.77, 95% CI: 1.14-2.73). In addition, rs2066865 lost its significant association with VT risk after multiple correction testing was performed. Conversely, the prothrombin mutation (rs1799963) did not show any significant association. The AUC of Leiden mutation (rs6025) showed better discriminative accuracy than that of other SNPs (AUC = 0.62, 95% CI: 0.57-0.66). The wGRS was a better predictor for VT than the unGRS (AUC = 0.67 vs. 0.65). Furthermore, combining genetic and non-genetic VT risk factors significantly increased the AUC to 0.89 with statistically significant differences (Z = 3.924, p < 0.0001).

Conclusions

Our study revealed that the five strongly associated SNPs combined with non-genetic factors could efficiently predict individual VT risk susceptibility. The combined model was the best predictor of VT risk, so stratifying high-risk individuals based on their genetic profiling and well-known non-modifiable VT risk factors was important for the effective and efficient utilization of VT risk preventive and control measures. Furthermore, we urged further study that compares the VT risk predictability in the Hungarian population using the formerly discovered VT SNPs with the novel strongly associated VT SNPs.

Association Between ABO Blood Group and Venous Thromboembolism Risk in Patients With Peripherally Inserted Central Catheters: A Meta-analysis and Systematic Review

Background

Previous studies have evaluated the association between ABO blood group and venous thromboembolism (VTE) risk in patients with peripherally inserted central catheters (PICCs). However, it remains unclear whether ABO blood groups are associated with PICC-associated VTE risk. Therefore, we conducted a meta-analysis of related studies to elucidate the potential role of ABO blood group as a risk factor for PICC-associated VTE.

Methods

All detectable case-control and cohort studies comparing the role of ABO blood group as a risk factor for PICC-associated VTE were collected for this analysis by searching PubMed, Embase, CNKI, Web of Science, and Wanfang. We conducted a meta-analysis of the eligible studies and computed the summary risk estimates with random or fixed effects models.

Results

A total of four studies involving 7,804 patients were included. Meta-analysis of the studies showed that the risk of PICC-associated VTE was significantly higher in blood types A [odds ratio (OR)=1.54, 95% CI=1.17-2.03), p=0.002], B (OR=2.35, 95% CI=1.71-3.23, p<0.0001), and AB (OR=2.55, 95% CI=1.68-3.88, p<0.0001) and lower in blood types O (OR=0.58, 95% CI=0.45-0.74, p<0.0001). Subgroup analysis based on ethnicity demonstrated that blood type O may be a genetic protective factor for PICC-associated VTE in Asians. Among Caucasians, individuals with blood types B and AB have a higher risk of PICC-associated VTE. Blood types A, B, and AB are risk factors for PICC-associated VTE in Asians.

Conclusions

Blood type O is associated with a decreased risk of PICC-associated VTE, especially in Asian populations. Moreover, blood types A, B, and AB are risk factors for PICC-associated VTE.

ABO blood type association with SARS-CoV-2 infection mortality: A single-center population in New York City

Background

Severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) has a variable clinical course with significant mortality. Early reports suggested higher rates of SARS‐CoV‐2 infection in patients with type A blood and enrichment of type A individuals among COVID‐19 mortalities.

Study Design and Methods

The study includes all patients hospitalized or with an emergency department (ED) visit who were tested for SARS‐CoV‐2 between March 10, 2020 and June 8, 2020 and had a positive test result by nucleic acid test (NAT) performed on a nasopharyngeal swab specimen. A total of 4968 patients met the study inclusion criteria, with a subsequent 23.1% (n = 1146/4968) all‐cause mortality rate in the study cohort. To estimate overall risk by ABO type and account for the competing risks of in‐hospital mortality and discharge, we calculated the cumulative incidence function (CIF) for each event. Cause‐specific hazard ratios (csHRs) for in‐hospital mortality and discharge were analyzed using multivariable Cox proportional hazards models.

Results

Type A blood was associated with the increased cause‐specific hazard of death among COVID‐19 patients compared to type O (HR = 1.17, 1.02–1.33, p = .02) and type B (HR = 1.32,1.10–1.58, p = .003).

Conclusions

Our study shows that ABO histo‐blood group type is associated with the risk of in‐hospital death in COVID‐19 patients, warranting additional inquiry. Elucidating the mechanism behind this association may reveal insights into the susceptibility and/or immunity to SARS‐CoV‐2.

Roles of genetics and blood type in clinical responses to COVID-19: ethical and policy concerns

Recently, several genetic variants have been associated with increased or decreased risks of becoming infected and/or seriously ill with COVID-19-not only offering important potential medical benefits but also posing critical ethical questions. These genetic factors, some of which are associated with blood type, may account for variations in observed responses to COVID-19. Hence, assessments of these genetic differences and blood type could provide possible benefits in gauging patients' risks of disease acquisition and prioritising allocation of interventions or vaccines, if supplies are limited. The media has widely reported these findings, and people online are now discussing their blood type and its possible effects on their COVID-19 risks, but several ethical concerns arise. Individuals possessing genetic variants or blood types associated with lower risk may engage in 'risk compensation', erroneously assuming that they can protect themselves less, and hence less frequently wearing masks or washing hands. Given the ongoing COVID-19 pandemic, many physicians, hospitals, patients, policymakers, members of the public, testing companies and others may well consider these factors in making critical prevention/treatment decisions. Researchers, providers and others should thus begin to address these concerns. Increased awareness and education aimed at providers, patients, family members, public health officials, political leaders and the public-at-large are critical. Attitudinal research is vital to examine how providers, patients and the public understand these findings. Ethical frameworks and guidelines are needed, addressing whether such genetic information should be incorporated into decisions regarding allocation of scarce resources-including hospital and ICU beds, ventilators, medications (eg, remdesivir) and vaccines-and if so, how.

Blood type and postpartum hemorrhage by mode of delivery: A retrospective cohort study

OBJECTIVE

To assess the relationship between postpartum hemorrhage and ABO blood type for vaginal delivery and cesarean delivery.

STUDY DESIGN

This is a retrospective cohort study of data abstracted from the PeriBank database regarding demographics and delivery outcomes. All live singleton deliveries from January 2011 until March 2018 were included in this study. Exclusion criteria were sickle cell disease and multiple gestations. Analyses were conducted separately for cesarean delivery and vaginal delivery. Quantitative variables were analyzed with analysis of variance testing and categorical variables with chi square testing. Significant demographic differences between groups were controlled for using multivariate logistical regression. The primary outcome was the rate of postpartum hemorrhage by blood type (A, B, AB, and O), defined as blood loss >500 mL in vaginal delivery and >1000 mL in cesarean delivery. 43,437 patients were screened and 32,023 women met inclusion criteria (22,484 vaginal deliveries (70.2%) and 9539 cesarean deliveries (29.8%)).

RESULTS

In the vaginal delivery group there were differences in age, parity, race, use of regional anesthesia, rate of induction of labor, and thrombocytopenia between blood types. In the cesarean delivery group, age, parity, and race were significantly different between blood types. There was no observed difference in the rate of postpartum hemorrhage by blood type for those who delivered via vaginal delivery when controlling for demographic differences (p = 0.2). In the cesarean delivery group, there was a significantly higher rate of postpartum hemorrhage in women with type O blood (5.2% type O vs 3.8% type A vs 4.4% type B vs 4.2% type AB, p = 0.035), including when controlling for demographic differences (p = 0.02). In both vaginal and cesarean delivery groups, there was no difference in rates of any of the secondary outcomes, including blood transfusion, hysterectomy, intrapartum dilation and curettage, and intensive care unit admission.

CONCLUSION

Although this study found no statistically significant difference in clinical outcomes between blood types, type O blood may be an additional risk factor to consider for postpartum hemorrhage at the time of cesarean delivery.

Association between ABO blood group and venous thrombosis related to the peripherally inserted central catheters in cancer patients

OBJECTIVE

To evaluate the potential relation between the ABO blood group and the risk of venous thrombosis in cancer patients with peripherally inserted central catheters (PICCs).

METHODS

The patients who underwent PICC catheterization in Beijing Cancer Hospital from January 2018 to October 2019 were retrospectively analyzed. The general information, disease diagnosis, catheterization situation, and complications were recorded for each patient. Further, the blood group status was identified using the hospital information systems. Logistic and Cox proportional hazard regression analyses were performed to identify the risk factors for symptomatic PICC-related thrombosis.

RESULTS

Among the 2315 patients, 131 had symptomatic thrombosis after PICC catheterization. The incidence of symptomatic thrombosis was lower in patients with blood type O when compared with that in patients with blood types other than O. The history of venous thrombosis, tumor category, arm circumference, and insertion attempts are risk factors associated with the PICC-related venous thromboembolism (VTE). After multivariable adjustment, insertion attempts and the non-O blood type were observed to remain associated with thrombosis.

CONCLUSION

The risk of PICC-related thrombosis in patients with non-O blood type is significantly higher than that in patients with blood type O.

Immigration, region of origin, and the epidemiology of venous thromboembolism: A population-based study

BACKGROUND

Venous thromboembolism (VTE) epidemiology has been mainly studied in populations largely of European ancestry.

OBJECTIVES

To assess the epidemiology of VTE in immigrants to Ontario, Canada.

PATIENTS/METHODS

We conducted a population-based retrospective cohort study using linked health-care and administrative databases. We included 1 195 791 immigrants to Ontario and 1 195 791 nonimmigrants, matched on age, sex, and place of residence. The main exposure was ethnicity according to world region of origin, using a previously validated algorithm. The main outcome was incident onset of VTE during the period of observation. Risk ratios (RR) were calculated using Poisson regression models.

RESULTS

The incidence rate (IR) of VTE was lower among immigrants (0.87 per 1000 PY; 95% confidence interval [CI] 0.85-0.89) than nonimmigrants (1.59 per 1000 PY; 95% CI 1.56-1.61). Age- and sex-standardized IR were lower among East and South Asian immigrants. Compared to immigrants for predominantly White regions, age- and sex-specific RRs were consistently lower for East Asian (0.18-0.30) and South Asian (0.29-0.75) immigrants. In contrast, the RRs of VTE among Black (0.38-1.50), Latin American (0.29-1.25), Arab/Middle Eastern (0.44-1.08) and West Asian (0.31-1.16) immigrants were not significantly different from White immigrants.

CONCLUSIONS

In Ontario, the incidence of VTE is lower among immigrants compared to nonimmigrants. East and South Asian immigrants have a lower risk of VTE compared to White immigrants.

ABO blood group related venous thrombosis risk in patients with peripherally inserted central catheters

OBJECTIVE

To investigate the association between ABO blood group and upper limb venous thrombosis (VT) risk in patients with peripherally inserted central catheters (PICC).

METHODS

Single centre retrospective cohort study. A cohort of patients who underwent PICC insertion from September 2010 to August 2014 were followed up for symptomatic VT presentations diagnosed by ultrasound. Blood group status was identified from hospital information systems.

RESULTS

2270 participants had 3020 PICCs inserted. There were 124 cases of symptomatic VT, an incident rate of 4% [95% confidence interval, CI (3-5%)]. Univariate analysis adjusting for the clustered sample showed that having chemotherapy, two or more previous PICCs, a larger catheter size, a diagnosis of cancer and having a blood group B were all associated with an increased risk of a VT. In the multivariate analysis, PICC diameter, cancer diagnosis and blood group B were all independently associated with increased risk of VT.

CONCLUSION

Patients undergoing PICC insertion with a blood group B appear to have a higher risk of VT, independent of risks attached to the PICC procedure and cancer diagnosis. Without any existing guidelines for PICC-related VT, this investigation creates a platform for further research to be conducted in order to establish guidelines. Advances in knowledge: Previous studies investigating VT risk associated with blood group status related to large heterogeneous populations. In this article, we look at patients specifically with PICC, which reduces the heterogeneity in the cohort. In addition, due to the substantial number of patients enrolled, we had a chance to perform multivariate analyses with statistical significance.

Novel genetic predictors of venous thromboembolism risk in African Americans

Venous thromboembolism (VTE) is the third most common life-threatening cardiovascular condition in the United States, with African Americans (AAs) having a 30% to 60% higher incidence compared with other ethnicities. The mechanisms underlying population differences in the risk of VTE are poorly understood. We conducted the first genome-wide association study in AAs, comprising 578 subjects, followed by replication of highly significant findings in an independent cohort of 159 AA subjects. Logistic regression was used to estimate the association between genetic variants and VTE risk. Through bioinformatics analysis of the top signals, we identified expression quantitative trait loci (eQTLs) in whole blood and investigated the messenger RNA expression differences in VTE cases and controls. We identified and replicated single-nucleotide polymorphisms on chromosome 20 (rs2144940, rs2567617, and rs1998081) that increased risk of VTE by 2.3-fold (P< 6 × 10(-7)). These risk variants were found in higher frequency among populations of African descent (>20%) compared with other ethnic groups (<10%). We demonstrate that SNPs on chromosome 20 are cis-eQTLs for thrombomodulin (THBD), and the expression of THBD is lower among VTE cases compared with controls (P= 9.87 × 10(-6)). We have identified novel polymorphisms associated with increased risk of VTE in AAs. These polymorphisms are predominantly found among populations of African descent and are associated with THBD gene expression. Our findings provide new molecular insight into a mechanism regulating VTE susceptibility and identify common genetic variants that increase the risk of VTE in AAs, a population disproportionately affected by this disease.

Distribution of ABO blood groups in the patients with intracranial aneurysm and association of different risk factors with particular blood type

Introduction:

The association between ABO blood groups and intracranial aneurysms is not well-known. Many co-morbid factors are associated with intracranial aneurysms. Our objective was to assess the prevalence of different blood group in patients with intracranial aneurysm and to look for associations between risk factors and these groups.

Materials and Methods:

This retrospective study includes 1,491 cases who underwent surgical operations for intracranial aneurysms from 1993-2014. We have evaluated the information related to clinical history, ABO blood groups and associated risk factors in the patients both ruptured and unruptured intracranial aneurysms by chart review of the cases.

Results:

In our study, out of 1,491 cases, the most common ABO blood groups were group O (668 cases, 44.80%) and Group A (603 cases, 40.44%), and Rh(+) in 1,319 (88.4%) and Rh(-) in 147 (11.6%). Blood Group A (43% vs. 36%) and Group B (16.2% vs. 8.6%) were significantly higher in Caucasian and African Americans respectively. However, in general population, there was no significant difference in blood groups between Caucasians and African Americans. Rh(-) factor was significantly higher in Caucasians compared to African Americans. Incidence of smoking was significantly higher in aneurysm patients with O group compared to others. In addition, incidence of hypercholesterolemia was significantly higher in aneurysm patients with A group compared to others.

Conclusion:

The racial disparity in the distribution of blood groups, and risk factor association with blood groups in the development of intracranial aneurysm needs to be considered. The findings from our study may be useful in identifying patients at increased risk. Further study may be required to establish the risks from multiple centers studies around the world.

ABO blood types and cancer risk--a cohort study of 339,432 subjects in Taiwan

BACKGROUND

The associations of laboratory-based ABO phenotypes with cancer risks and mortality have not been systematically determined.

METHODS

The study subjects were 339,432 healthy individuals with laboratory-based blood types from a Taiwan cohort.

RESULTS

Compared to blood type O, blood type A was significantly associated with an elevated risk of stomach cancer incidence (Hazard Ratio [HR], 1.38 [95% CI, 1.11-1.72]) and mortality (HR, 1.38 [95% CI, 1.02-1.86]) compared with blood type O, after adjusting for age, sex, education, smoking, alcohol drinking, physical activity, and body mass index. Non-O blood types were associated with an elevated risk of pancreatic cancer, with blood type B reaching statistical significance for incidence (HR, 1.59 [95% CI, 1.02-2.48]) and mortality (HR, 1.63 [95% CI, 1.02-2.60]). In contrast, kidney cancer risk was inversely associated with blood type AB (HR, 0.41 [95% CI, 0.18-0.93]) compared to type O.

CONCLUSION

Cancer risks vary in people with different ABO blood types, with elevated risks of stomach cancer associated with blood type A and pancreatic cancer associated with non-O blood types (A, B, and AB).

Is ABO blood group truly a risk factor for thrombosis and adverse outcomes?

ABO blood type is one of the most readily available laboratory tests, and serves as a vital determinant in blood transfusion and organ transplantation. The ABO antigens are expressed not only on red blood cell membranes, determining the compatibility of transfusion, but also on the surface of other human cells, including epithelium, platelet and vascular endothelium, therefore extending the research into other involvements of cardiovascular disease and postoperative outcomes. ABO blood group has been recognized as a risk factor of venous thrombosis embolism since the 1960’s, effects now understood to be related to ABO dependent variations are procoagulant factor VIII (FVIII) and von Willebrand factor (vWF) levels. Levels of vWF, mostly genetically determined, are strongly associated with venous thromboembolism (VTE). It mediates platelet adhesion aggregation and stabilizes FVIII in plasma. Moreover, many studies have tried to identify the relationship between ABO blood types and ischemic heart disease. Unlike the clear and convincing associations between VTE and ABO blood type, the link between ABO blood type and ischemic heart disease is less consistent and may be confusing. Other than genetic factors, ischemic heart disease is strongly related to diet, race, lipid metabolism and economic status. In this review, we’ll summarize the data relating race and genetics, including ABO blood type, to VTE, ischemic heart disease and postoperative bleeding after cardiac surgery.

Venous thromboembolism risk factors in Chinese non-small cell lung cancer patients

PURPOSE

Certain clinicopathological factors contribute to the development of venous thromboembolism (VTE) in lung cancer. The aim of the current study was to assess the incidence of and the potential risk factors associated with the development of VTE in Chinese lung cancer patients.

METHODS

Patients with lung cancer in our center were screened for VTE from January 2004 to July 2013. One VTE case was matched with two controls according to gender, pathology, clinical stage, and anticancer therapy.

RESULTS

Among the 4,726 patient records screened, 61 (1.3 %) VTE cases with non-small cell lung cancer (NSCLC) were identified, including 58 (95.1 %) with adenocarcinoma and 59 (96.7 %) with advanced stage tumors (IIIb and IV). Serous effusion (OR 2.089, 95 % CI 1.022-4.270, P = 0.043), fever (OR 8.999, 95 % CI 1.688-47.968, P = 0.010), increased leukocytes (OR 4.136, 95 % CI 1.957-8.738, P < 0.001), hyponatremia (< 130 mmol/L, OR 5.335, 95 % CI 1.366-20.833, P = 0.016), and increased alanine aminotransferase (ALT) (OR 3.879, 95 % CI 1.514-9.936, P = 0.005) were associated with an increased risk of VTE. Patients with poor performance status (PS) (≥ 2 vs. < 1) (HR 1.574, 95 % CI 1.112-2.228, P = 0.010) and serous effusion (HR 1.571, 95% CI 1.114-2.215, P = 0.010) tended to have a poor prognosis. There was no difference in overall survival between VTE (median 15.2 months, 95 % CI 11.6-18.9) and control patients (median 16.3 months, 95 % CI 14.1-18.4, P = 0.184; HR 1.273, 95 % CI 0.890-1.820, P = 0.185).

CONCLUSIONS

Clinical characteristics such as serous effusion, fever, increased leukocytes, hyponatremia, and increased ALT are potential risk factors for VTE in NSCLC. Poor PS and serous effusion imply poor prognosis for NSCLC patients, most of which have adenocarcinomas and advanced stage.