ABO blood groups and thrombosis: a causal association, but is there value in screening?

The ABO Blood System and Associated Implications for Hemostasis and Thrombosis

The relationship between non-O blood groups and thromboembolic events has been suggested by several studies, although the exact underlying mechanisms are not fully elucidated. However, the correlation between ABO blood groups with the opposite pole of hemostasis, hemorrhage, has been investigated less thoroughly. Non-O blood groups confer an overall increased risk of single, recurrent, and provoked thromboembolic episodes. On the other hand, blood group O has been associated with more severe bleeding events and less favorable manifestations in individuals with hemorrhagic disorders. Therefore, ABO blood group screening may have a role in both thrombotic and hemorrhagic risk assessment and could potentially be added to available clinical prediction systems. This strong belief is supported by the ongoing research. Nevertheless, up to date, the majority of studies represent important heterogeneity, and given the frequency of non-O blood groups, a natural reluctance to incorporate blood groups in risk assessment models arises. Therefore, a more targeted approach should be considered to provide safe outcomes. The in vitro estimation of the thrombotic and hemorrhagic profile of each blood group separately, the quantitative estimation of VWF, FVIII, and platelet function in several disease settings and in well-organized studies, could be useful to establish a clear relationship of ABO blood types with hemostatic and thrombotic disorders. This may ensure a safe approach to categorizing a patient's risk, managing treatment, and influencing prognosis.

The effect of histo-blood group ABO system transferase (BGAT) on pregnancy related outcomes：A Mendelian randomization study

Protein level of Histo-Blood Group ABO System Transferase (BGAT) has been reported to be associated with cardiometabolic diseases. But its effect on pregnancy related outcomes still remains unclear. Here we conducted a two-sample Mendelian randomization (MR) study to ascertain the putative causal roles of protein levels of BGAT in pregnancy related outcomes. Cis-acting protein quantitative trait loci (pQTLs) robustly associated with protein level of BGAT (P < 5 ×10-8) were used as instruments to proxy the BGAT protein level (N = 35,559, data from deCODE), with two additional pQTL datasets from Fenland (N = 10,708) and INTERVAL (N = 3301) used as validation exposures. Ten pregnancy related diseases and complications were selected as outcomes. We observed that a higher protein level of BGAT showed a putative causal effect on venous complications and haemorrhoids in pregnancy (VH) (odds ratio [OR]=1.19, 95% confidence interval [95% CI]=1.12-1.27, colocalization probability=91%), which was validated by using pQTLs from Fenland and INTERVAL. The Mendelian randomization results further showed effects of the BGAT protein on gestational hypertension (GH) (OR=0.97, 95% CI=0.96-0.99), despite little colocalization evidence to support it. Sensitivity analyses, including proteome-wide Mendelian randomization of the cis-acting BGAT pQTLs, showed little evidence of horizontal pleiotropy. Correctively, our study prioritised BGAT as a putative causal protein for venous complications and haemorrhoids in pregnancy. Future epidemiology and clinical studies are needed to investigate whether BGAT can be considered as a drug target to prevent adverse pregnancy outcomes.

Research into New Molecular Mechanisms in Thrombotic Diseases Paves the Way for Innovative Therapeutic Approaches

Thrombosis is a multifaceted process involving various molecular components, including the coagulation cascade, platelet activation, platelet-endothelial interaction, anticoagulant signaling pathways, inflammatory mediators, genetic factors and the involvement of various cells such as endothelial cells, platelets and leukocytes. A comprehensive understanding of the molecular signaling pathways and cell interactions that play a role in thrombosis is essential for the development of precise therapeutic strategies for the treatment and prevention of thrombotic diseases. Ongoing research in this field is constantly uncovering new molecular players and pathways that offer opportunities for more precise interventions in the clinical setting. These molecular insights into thrombosis form the basis for the development of targeted therapeutic approaches for the treatment and prevention of thrombotic disease. The aim of this review is to provide an overview of the pathogenesis of thrombosis and to explore new therapeutic options.

Blood group as a novel predictor of postoperative atrial fibrillation after off-pump coronary artery bypass grafting

OBJECTIVE

The objective of this study was to reveal whether there was a possible relationship between the blood group and postoperative atrial fibrillation after off-pump coronary artery bypass grafting.

METHODS

Between January 2020 and January 2022, 452 patients undergoing off-pump coronary artery bypass grafting surgery consisted of the research population. Patients were divided into two groups based on the occurrence of new-onset atrial fibrillation from the time of operation until discharge. Group 1 (atrial fibrillation group) had 122 patients, whereas group 2 (non-atrial fibrillation group) contained 350 patients. Patients' baseline clinical characteristics and operative and postoperative data were recorded and then compared between the groups. Moreover, a multivariate logistic regression analysis was also conducted to identify the predictors of postoperative atrial fibrillation.

RESULTS

Non-O blood groups were substantially more common in the atrial fibrillation group than in the non-atrial fibrillation group. Patient age differences between the atrial fibrillation and non-atrial fibrillation groups were statistically significant, and patients in the atrial fibrillation group were detected to be older. Mean left atrial diameter, rates of obesity and prior percutaneous coronary intervention history, and perioperative intraaortic balloon pump requirement were significantly greater in the atrial fibrillation group than in the non-atrial fibrillation group. According to logistic regression analysis, blood group, age, left atrial diameter, obesity, and prior percutaneous coronary intervention were identified as predictors of postoperative atrial fibrillation.

CONCLUSION

We demonstrated for the first time in the literature that ABO blood type was a novel and significant predictor of new-onset atrial fibrillation after off-pump coronary artery bypass grafting.

Systematic Review and Meta-Analysis of the Susceptibility of ABO Blood Groups to Venous Thromboembolism in Individuals with Factor V Leiden

A limited number of studies investigated the association between the ABO blood groups and the incidence of venous thromboembolism in individuals with Factor V Leiden; however, discordant findings were reported. Consequently, this systematic review and meta-analysis aimed to evaluate the existing evidence on the susceptibility of the ABO blood group to venous thromboembolism in individuals with Factor V Leiden. All English-published articles on the Web of Science, Scopus, PubMed, EMBASE, and Google Scholar were comprehensively and systematically searched by the author without a time or region limit. Four studies were included in the qualitative synthesis and meta-analysis after the removal of studies that were not eligible. According to the analyses of the fixed and random effects, the point estimates of the effect size and the 95% confidence interval were 0.416 (95% CI: 0.397−0.435) and 0.392 (95% CI: 0.288−0.507), respectively. In contrast, the homogeneity test (Q value) reveals that blood group data distributions have a heterogenous structure (Q = 432.187; p-value < 0.001). The pooled event rates and the 95% CIs for the A, AB, B, and O-blood groups were 0.518 (95% CI: 0.411−0.622), 0.592 (95% CI: 0.495−0.683), 0.205 (95% CI: 0.041−0.612), and 0.283 (95% CI: 0.247−0.322), respectively. According to the findings, people with Factor V Leiden with blood group AB are more likely to develop venous thromboembolism than those with blood groups A, O, and B. The overall statistical significance of the ABO blood group’s susceptibility to venous thromboembolism in individuals with Factor V Leiden was <0.001 (pooled p-value). In conclusion, the current meta-analysis provides an additional indication that blood group AB individuals with Factor V Leiden are at higher risk of developing venous thromboembolism, and blood type B is connected to a lower risk of developing venous thromboembolism.

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.

A1B and BB blood group genotypes are risk factors for pulmonary embolism

BACKGROUND

Pulmonary embolism (PE) is a potentially life-threatening condition that mainly affects the people of advanced age. While certain blood group phenotypes (non‑O blood group) are known risk factors for the development of venous thromboembolism (VTE), there is no research which investigated the association of blood group genotypes with severity of PE. The aim of this study was to investigate the frequency of ABO blood group genotypes among the population of patients with PE and to investigate the correlation of the pulmonary embolism severity index (PESI) score to specific ABO blood group genotypes.

MATERIAL AND METHODS

In this cross-sectional study 74 patients with PE diagnosed using CT pulmonary angiography were included and 303 blood donors without VTE or congenital thrombophilia participated as a control group. After isolation of genomic DNA ABO blood group genotype was determined using the polymerase chain reaction sequence-specific amplification (PCR-SSP) method.

RESULTS

We observed a significantly higher frequency of A1B and BB genotypes in patients with PE compared to healthy individuals (A1B 14.9% vs. 4.3%, P < 0.001; BB 5.4% vs. 0.7%, P = 0.004), while the O1O1 genotype was significantly less frequent in patients (24.3% vs. 37.3%, P = 0.036). Analyzing the severity of the clinical presentation according to the PESI score, we did not find a correlation between the severity of the clinical presentation and a certain blood type genotype.

CONCLUSION

Patients with A1B and BB blood type genotype were at increased risk for developing pulmonary embolism, while patients with O1O1 genotype had a significantly lower risk of developing PE.

Effect of ABO Blood Groups on the Response to Warfarin

BACKGROUND

Numerous studies have demonstrated that patients with non-O blood groups have a higher risk for venous thromboembolism than those with the O blood group. However, the effect of ABO blood groups on warfarin dose requirements in patients receiving anticoagulation in the Chinese Han population remains unknown. This study aimed to investigate the influence of ABO blood groups on warfarin dose requirements in a Chinese Han population.

MATERIAL AND METHODS

A retrospective study was conducted in the First Affiliated Hospital of Shantou University Medical College in South China. Three hundred and fifty-eight patients with a confirmed diagnosis of deep vein thrombosis or atrial fibrillation were included. The frequency of blood groups and warfarin dose requirements were determined.

RESULTS

Of 358 patients with deep vein thrombosis or atrial fibrillation, 111 patients had blood group A (31.01%), 104 patients had blood group B (29.05%), 20 patients had blood group AB (5.59%) and 123 patients had blood group O (34.36%). The patients in the O blood group had lower warfarin dose requirements than those in the A, B and AB blood groups.

CONCLUSIONS

Our study showed that patients with non-O blood groups require higher doses of warfarin.

Association of ABO blood groups and Rh factor with retinal and choroidal thickness

PURPOSE:

To evaluate if ABO blood group and Rh factor have an effect on retinal and choroidal thickness.

METHODS:

This study was designed prospectively. Retinal nerve fiber layer, retinal, and choroidal thicknesses were measured with spectral-domain optical coherence tomography. Retinal and choroidal thickness measurements (one subfoveal, three temporal, and three nasal) were obtained at 500-μm intervals up to 1500 μm with the caliper system.

RESULTS:

In this study, 109 male and 151 female, 260 individuals in total were included. There were 125 subjects in group A, 29 in group B, 34 in group AB, and 72 in group O. Rh factor was positive in 194 subjects and negative in 66. There was no significant difference between the groups regarding age (p = 0.667). The groups did not show any statistical difference in retinal nerve fiber layer thickness. There was significant difference found for mean retinal thickness at temporal 1000 μm when four groups were compared (p = 0.037). No statistically significant difference was detected for the remaining retinal and choroidal sectoral regions. The groups did not statistically significantly differ concerning Rh factor (p > 0.05).

CONCLUSION:

Although we found a significant difference in retinal thickness in the temporal retina between group B with group A and group O, we suggest that both blood group and Rh factor have no effect on retinal and choroidal thickness.

The relationship between immunogenic red blood cell antigens and Human Immunodeficiency Virus infection

INTRODUCTION

Evidence suggests that red cell antigens may act as receptors for viruses and bacteria and therefore could be associated with HIV infection. Previous studies have been controversial and therefore the aim of this exploratory study was to analyse the expression of immunogenic red cell antigens in HIV-seropositive individuals and to compare the results to negative donors from South Africa.

METHODS

The expression of ABO, Rh, Kell and Duffy antigens from 119 HIV-seropositive patients was compared to 317 HIV-seronegative blood donors. Nucleic acid amplification testing and PCR were used to determine the HIV status and the ID-Gel Card Technology was used to determine the blood group antigen profile.

RESULTS

There was no significant difference in the expression of A, B, AB, Duffy or Kel antigens between the two groups but significantly lower numbers of HIV+ individuals were O Rh Negative (p = ,0.0001). Analysis of those with a Duffy null phenotype revealed a significantly higher incidence of blood type A RH1-Positive, Dce/R⁰r and B RH1-Positive, DcEe/R²r within the HIV-seropositive group (p = < 0.05). None of the HIV-seropositive individuals were O RH1-Negative, dce/rr.

CONCLUSION

In conclusion these initial findings have demonstrated a decreased incidence of blood type O Rh1-negative in HIV + individuals which suggests that red blood cell antigens may play an important role in susceptibility to HIV infection. The relationship between red cell antigens and HIV infection however remains complex and therefore larger studies are required to confirm these results.

ABO blood groups and risk of deep venous thromboembolism in Chinese Han population from Chaoshan region in South China

 Objectives: To demonstrate the prevalence of ABO blood groups with deep venous thromboembolism in Chinese Han population.

METHODS

A retrospective study was conducted between January 2010 and March 2015 in The First Affiliated Hospital of Shantou University Medical College in Chaoshan District of Guangdong Province in South China. Eighty nine patients with confirmed diagnosis of deep venous thromboembolism were included. Frequency of blood groups was determined. Results: Of 89 patients with deep venous thromboembolism, 28 patients had blood group A (31.5%), 28 patients had blood group B (31.5%), 13 patients had blood group AB (14.6%), and 20 patients had blood group O (22.5%). Compared with O blood type, the odds ratios of deep venous thromboembolism for A, B and AB were 2.23 (95% CI, 1.27-3.91), 2.34 (95% CI, 1.34-4.09) and  4.43 (95% CI, 2.24-8.76). Conclusion: There is a higher risk of venous thromboembolism in non-O blood groups than O group.

Blood groups and acute aortic dissection type III

INTRODUCTION

Acute aortic type III dissection is one of the most catastrophic events, with in-hospital mortality ranging between 10% and 12%. The majority of patients are treated medically, but complicated dissections, which represent 15% to 20% of cases, require surgical or thoracic endovascular aortic repair (TEVAR). For the best outcomes adequate blood transfusion support is required. Interest in the relationship between blood type and vascular disease has been established. The aim of our study is to evaluate distribution of blood groups among patients with acute aortic type III dissection and to identify any kind of relationship between blood type and patient's survival.

MATERIAL AND METHODS

From January 2005 to December 2014, 115 patients with acute aortic type III dissection were enrolled at the Clinic of Vascular and Endovascular Surgery in Belgrade, Serbia and retrospectively analyzed. Patients were separated into two groups. The examination group consisted of patients with a lethal outcome, and the control group consisted of patients who survived.

RESULTS

The analysis of the blood groups and RhD typing between groups did not reveal a statistically significant difference (p = 0.220).

CONCLUSIONS

Our results indicated no difference between different blood groups and RhD typing with respect to in-hospital mortality of patients with acute aortic dissection type III.

ABO blood group and thrombotic vascular disease

ABO blood group antigens are complex carbohydrate molecules expressed on red blood cells and a variety of tissues. The ABO blood type is implicated in the development of a number of human diseases and there is increasing evidence regarding its involvement in the pathogenesis of cardiovascular disorders, mainly through its effect on von Willebrand factor levels. In this review, after a brief analysis of the potential molecular mechanisms by which the blood group influences haemostasis, we focus on the clinical implications of such interaction. Overall, the literature data document the close relationship between venous thromboembolism (VTE) and non-O blood type, which is associated with an approximately two-fold increased risk of venous thrombosis. A supra-additive effect on VTE risk is observed when an inherited thrombophilic condition is associated with non-O blood group. A weaker association exists between non-O blood type and arterial thrombosis, which needs to be further investigated.

Risk factors for thrombosis in an african population

SUMMARY

Little is known about the biological, epidemiological, and clinical risk factors for thrombosis and venous thromboembolism (VTE) among Black Africans. We undertook a study of the prevalence of VTE risk factors for thrombosis in a Senegalese population.

A three-year cross-sectional and case–control study involving 105 cases and 200 controls was conducted in various hospitals in Dakar (Senegal). Our results demonstrate that oral contraception, immobilization by casts, surgery, and blood group were significantly associated with VTE occurrence. Additionally, 16 cases and 2 controls had protein S (PS) values of less than 48.4% (M-2SD), exhibiting a highly significant difference (P < 1 × 10⁻⁴). The number of cases with a low protein C (PC) level was significantly higher than the respective number of controls. Using logistic regression methods, we established a correlation between significantly associated variables and deep venous thrombosis (DVT) occurrence. Age, obesity, sickle cell disease, and PC deficiency were not significantly associated with thrombosis. In contrast, gender, PS deficiency, varicose veins, surgery, non-O blood type, and the presence of antiphospholipid antibodies were significantly and independently associated with DVT.

These findings are extremely useful for clinical management of patients suffering from DVT and can help to reduce the high recurrence rate observed in our study.

The role of red blood cells in enhancing or preventing HIV infection and other diseases

Aim. To highlight the apparently neglected role of erythrocyte antigens in the epidemiology of infectious diseases, especially HIV, with the prime objective of stimulating research in this area. Method. A literature search was performed on the PubMed for relevant papers from 1984 to 2013, the era covering active HIV research. This was achieved by using the phrases “erythrocyte blood groups HIV” (81 papers) or “red cell antigen, blood groups, and HIV” (60 papers). A manual Google Scholar search was done and supplemented by original papers referenced by various authors. However, the review was limited by the relative scarcity of papers on the subject, and only papers written in English were reviewed during the period October 2012 to September 2013. Results. Many communicable and noncommunicable diseases are associated with specific blood groups. Examples of these diseases are discussed in detail. HIV has been shown to bind to erythrocytes, and candidate erythrocyte-binding molecules and mechanisms are also discussed. Moreover, erythrocyte-HIV binding is associated with increased viral infectivity, thus, underscoring the need to study this phenomenon and its implications for HIV epidemiology. Conclusion. Erythrocyte antigens may be important in the pathogenesis and epidemiology of many diseases, including HIV.

Ascending aorta aneurysm and blood group A among Iranian patients

BACKGROUND

Ascending aortic aneurysm is a life threatening conditions leading to surgery in many cases. Demonstrating risk factors for this disease is essential for development of screening strategies for high-risk populations. Blood group although described as a potential risk factor for abdominal aortic aneurysm, has not been addressed in patients with aneurysm of the ascending aorta.

OBJECTIVES

Our study aimed to demonstrate the prevalence of ABO blood groups among one of the largest Iranian population with diagnosed aneurysm of the ascending aorta.

METHODS

A retrospective study was conducted in Tehran Heart Center in Tehran, Iran reviewing profile of 24,433 patients admitted to the cardiac surgery ward between January 2005 and February 2012 to extract data of 96 patients with confirmed diagnosis of ascending aortic aneurysm (AAA). Frequency of blood groups was determined and risk factors and AAA-related complications and mortality were compared between different blood groups.

RESULTS

Of ninety six patients with AAA, 38 patients (39.58%) had blood group A, followed by 16 patients with blood group B (16.66%), 12 blood group AB (12.5%), and 30 patients (30.25%) with blood group O. Cerebrovascular accident (CVA), peripheral vascular disease (PVD), and AAA-related mortality were more frequent in patients with blood group A. However, it did not reveal statistically significant difference (p>0.05).

CONCLUSION

Our study showed that risk factors for developing vascular disease are more prevalent in patients with blood group A and this blood group is associated with higher complication and mortality in AAA.

The influence of maternal Lewis, Secretor and ABO(H) blood groups on fetal growth restriction

BACKGROUND

Fetal growth restriction (FGR) is associated with thrombosis of the placenta and an increased risk of subsequent vascular disease in the mother and fetus. The products of interactions between ABO(H), Lewis and Secretor genes are also associated with thrombosis and vascular disease risk.

OBJECTIVES/METHODS

A prospective case-control study of mothers with a severe FGR pregnancy (cases, n = 128; controls, n = 288) was performed to determine whether FGR is associated with particular maternal blood groups.

RESULTS

No association with ABO(H) status was observed, but FGR was more common in maternal secretors (odds ratio [OR] 1.70, 95% confidence interval [CI] 1.08-2.69) and consequently in those mothers expressing Le(b) on their red cells (OR 1.80, 95% CI 1.15-2.83), with a reduced risk in non-secretors and those expressing Le(a). Given the association between blood groups and both activated protein C resistance (APCR) and von Willebrand factor (VWF) levels, post hoc pilot studies on first-trimester APCR and VWF antigen levels and blood group genotypes were performed. No relationship with Lewis or Secretor was observed. Despite this, lower first-trimester VWF levels were observed in pregnancies subsequently complicated by FGR.

CONCLUSIONS

 This is the first study reporting a relationship between maternal Secretor/Lewis status and FGR. A link between blood groups and FGR is plausible, as both are associated with cardiovascular disease. We observed no relationship between Lewis/Secretor status and VWF or APCR, but this should be confirmed in a larger study. Thus, the mechanism whereby Secretor and/or Lewis influences FGR is unknown.