ABO blood group and risk of coronary heart disease in two prospective cohort studies

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.

Association Between ABO Blood Group, Peripheral Artery Disease Lesion Severity, and Coronary Artery Disease Coexistence

BACKGROUND

This study aims to investigate the relationship between ABO blood groups and the severity of peripheral artery disease (PAD) lesions, the coexistence of coronary artery disease (CAD) with PAD, and to identify which blood groups may be more predisposed to these conditions.

METHODS

This study, which has a single-center and retrospective design, includes 305 patients diagnosed with peripheral artery disease (PAD) between 2015 and 2021. The patients were selected from those with at least 50% stenosis detected by computed tomography (CT) angiography. The severity of PAD lesions was evaluated according to the TransAtlantic Inter-Society Consensus (TASC-II) classification, and the presence of CAD was determined by simultaneous conventional coronary angiography. Demographic data, comorbidities, and laboratory results were collected, and statistical analyses were performed using chi-square tests, logistic regression, and t-tests. All of these patients were divided into 2 groups based on their ABO blood types: O and non-O blood groups.

RESULTS

This study demonstrates a significant relationship between blood group classification and both the severity of PAD and the prevalence of CAD. Patients with non-O blood groups exhibited a higher likelihood of having severe PAD lesions (TASC-C and TASC-D) compared to those with O blood groups, who more frequently had milder lesions (TASC-A and TASC-B) (P < 0.001). The prevalence of CAD was also significantly higher among patients with non-O blood groups than those with the O blood group (54.4% vs. 36.4%; P = 0.003). In the logistic regression analysis, non-O blood groups, alongside age, hypertension (HT), and chronic kidney disease (CKD), emerged as independent predictors of severe PAD (P < 0.001 for non-O blood groups). Similarly, older age and non-O blood group status were identified as significant independent predictors of CAD (P = 0.004). These findings suggest that blood group classification, particularly non-O groups, may influence the severity and coexistence of PAD and CAD.

CONCLUSION

Our study reveals a significant association between ABO blood groups and both the severity of PAD and the association of CAD, and shows that non-O blood groups are linked to more severe forms of these conditions. These findings highlight the potential role of ABO blood groups in cardiovascular risk stratification, suggesting a need for further research to confirm these associations and understand their clinical implications.

Blood group is a long-term cardiovascular risk factor after carotid endarterectomy

BACKGROUND

ABO blood group system has been clinically related to an increased incidence of cardiovascular diseases. Preliminary data relating Rhesus (Rh) factor and these outcomes also have been published. Our aim was to analyse the impact of blood group on the short and long-term outcomes after carotid endarterectomy (CEA).

MATERIALS AND METHODS

From 2012 to 2019, patients from a referral centre who underwent CEA for atherosclerotic carotid stenosis were prospectively followed. Our primary outcomes were long-term major adverse cardiovascular events (MACEs) and all-cause mortality. Secondary outcomes were perioperative complications and myocardial injury after non-cardiac surgery (MINS). Median follow-up was 50 months (interquartile range 21-69). Time-to-event analysis was used to determine the effect of ABO and Rh groups in long-term outcomes.

RESULTS

One hundred and eighty-four patients were included, with a mean age of 70.1 ± 9.1 years. Eighteen (25.7%) patients with O type and 48 (42.1%) patients with non-O type presented coronary artery disease (odds ratio [OR]: 2.313, 5-95% confidence interval (CI) 1.245-4.297, p = .008). Patients Rh+ presented significantly more congestive heart failure, 23 (14.7%), p = .03. The incidence of MACE in the long-term was higher in non-O patients (adjusted hazard ratio: 2.034; CI: 1.032-4.010, p = .040). Rh- patients, presented a higher incidence of perioperative MINS. However, there was no statistically significant association with long-term risk of MACE.

CONCLUSION

The incidence of MACE in long-term analysis was higher in non-O blood type and 30-day MINS was significantly more common amongst Rh- patients. The benefit from a more complete preoperative cardiac study in these patients should be performed.

Blood Group B May Reduce Risk of Rebleeding in Patients With Upper Gastrointestinal Haemorrhage due to Peptic Ulcer Disease

Risk stratification tools for the prediction of complications in patients with upper gastrointestinal haemorrhage are crucial for appropriate management. Blood group status has been associated with the risk of bleeding, thrombosis and risk of peptic ulcer disease (PUD). We assessed the influence of blood group status on rebleeding and other complications in 699 patients with PUD bleeding. Blood group B was associated with reduced risk in the composite outcome of rebleeding, need for surgery or embolisation and mortality (OR 0.15, 95% CI 0.04-0.63, p = 0.009). Blood group B was protective against rebleeding compared to non-blood group B (OR 0.20, 95% CI 0.05-0.84, p = 0.028).

Is ABO blood type a risk factor for adjacent segment degeneration after lumbar spine fusion?

PURPOSE

This study aimed to explore associations between ABO blood type and postoperative adjacent segment degeneration/disease (ASD) following lumbar spine fusion, as well as evaluate differences in spinopelvic alignment, perioperative care, postoperative complications, and patient-reported outcome measures (PROMs).

METHODS

An ambispective study was performed. Patients who underwent posterolateral or posterior lumbar interbody fusion were included. Demographic, perioperative and postoperative, clinical, and blood type information was recorded. Pre- and post-operative radiographic imaging was analyzed for alignment parameters and development of ASD.

RESULTS

445 patients were included, representing O+ (36.0%), O- (5.2%), A+ (36.2%), A- (6.3%), B+ (12.1%), B- (1.6%), and AB+ (2.7%) blood types. Most patients were female (59.1%), and had a mean age of 60.3 years and BMI of 31.1 kg/m2. Postoperatively, groups did not differ in duration of the hospital (p = 0.732) or intensive care unit (p = 0.830) stay, discharge disposition (p = 0.504), reoperation rate (p = 0.192), or in-hospital complication rate (p = 0.377). Postoperative epidural hematoma was most common amongst A + patients (p = 0.024). Over a mean of 11.0 months of follow-up, all patients exhibited similar improvement in PROMs, with 132 (29.7%) patients developing radiographic evidence of ASD. B + patients were significantly more likely than A + and O + patients to develop spondylolisthesis and ASD (p < 0.05). No significant differences in sagittal alignment parameters and number of levels of fusion were found (p > 0.05).

CONCLUSIONS

This is the first large-scale study to address and demonstrate proof-of-principle that ABO blood type, a non-modifiable risk factor, is associated with ASD following lumbar spine fusion.

S. ABO Blood Group and Auditory Function in Young Adults

Introduction

In recent years, research on the effect of blood group on hearing function has gained more attention. Some blood groups show susceptibility to certain general health and auditory disorders like noise induced hearing loss, infections, coronary artery disease, gastric carcinoma and duodenal ulcer.

Aims

The present study aimed to determine the differences in middle ear and cochlear function among persons with different blood groups (AB, A, B, O).

Materials and methods

Sixty adults (18-24 years) with normal hearing sensitivity were included in the study. They were divided into four groups based on blood groups (A, B, AB, O) with 15 participants each. High-frequency thresholds, distortion product otoacoustic emissions (DPOAE) and resonance frequency were measured. High-frequency thresholds for both ears were measured at octave frequencies from 9 kHz to 16 kHz. Resonant frequency was determined using sweep frequency method.

Results

The findings demonstrated that individuals with blood group AB and O had considerably lower DPOAE amplitudes. Resonance frequency and extended high frequency thresholds did not, however, differ significantly between the blood groups.

Conclusion

The decrease in the amplitude of otoacoustic emissions (OAE) can be explained by a reduction in the quantity of robust outer hair cells and elevated protein levels, which in turn lead to a reduction in the cochlear blood flow in persons with blood type O and AB, respectively. More research with greater numbers of participants is necessary to improve the generalization of the findings.

Relationship Between Blood Groups and Cardiovascular Diseases: Insights From an Algerian Inpatient Study

INTRODUCTION

 Research on the association between blood groups and cardiovascular diseases (CVDs) in Africa, including Algeria, is notably limited, with a primary focus on blood donors. This narrow scope hinders a comprehensive understanding of the genetic diversity of blood groups and their potential links to CVD risk within the African context. To bridge this knowledge gap, this study proposes to investigate the distribution of blood group genotypes and their association with CVD prevalence, aiming to enhance knowledge within the African context and contribute to global insights into the relationship between blood groups and CVD.

METHODS

 This retrospective study was conducted within the Cardiology A2 Department of Mustapha Bacha University Hospital (CHU) in Algiers, Algeria. The inclusion criteria comprised patients aged 18 years or older with confirmed diagnoses of CVDs. Conversely, patients without confirmed diagnoses or documented blood groups were excluded from the study. Data collection encompassed key cardiovascular risk factors, and blood groups were determined using standard serological testing methods. Statistical analyses were performed utilizing R and Jamovi software, with a predefined significance threshold of p < 0.05.

RESULTS

 Our analysis of a 2,780-patient cohort (61.7% male, mean age: 62.53 ± 13.06 years) revealed a predominance of blood type O (42.84%), followed by A (32.27%), B (16.19%), and AB (8.71%), with 93.42% of the cohort being Rhesus (Rh)-positive. The calculated ABO allele frequencies were 0.2315 (A), 0.1319 (B), and 0.6532 (O), indicating a significant deviation from Hardy-Weinberg equilibrium (HWE) (χ² = 47.88, p < 0.05), whereas the Rh distribution remained in equilibrium. Hypertension (94.50%), dyslipidemia (94.03%), and diabetes (79.57%) were the most prevalent cardiovascular risk factors. Acute coronary syndrome (ACS) was the leading diagnosis (39.75%), and notably, no significant associations were observed between blood groups and cardiovascular conditions or risk factors, except for a marginally higher prevalence of arrhythmia among Rh-negative (Rh-) individuals (9.29% vs. 5.81%).

CONCLUSION

 This study provides novel insights into the distribution of ABO and Rh blood types among Algerian patients with CVD, highlighting a prevalence of Group O and Rh-positive (Rh+) individuals, though without significant associations between blood groups and major cardiovascular risk factors. Contrary to previous findings suggesting elevated cardiovascular risk in non-O blood groups, our results did not establish significant associations between blood groups and cardiovascular conditions or risk factors. The high prevalence of ACS, hypertension (particularly among older males), dyslipidemia, and smoking underscore the urgent need for targeted preventive strategies and further research to elucidate the complex interplay between blood types, genetic factors, and CVD in this population. These findings emphasize the necessity for addressing modifiable risk factors through education and preventive measures to improve cardiovascular outcomes.

Relationship of adhesion molecules (ICAM-1 and E-selectin) with ABO blood groups in patients hospitalized with acute myocardial infarction

Objectives

Adhesion molecules, sICAM-1 and sE-selectin appear to have a major role in the pathogenesis of coronary artery disease (CAD). The focus of this study was to investigate the relationship of sICAM-1 and sE-selectin with ABO blood groups in Pakistani patients hospitalized with acute myocardial infarction (AMI).

Methods

In a case-control study, 116 patients of acute myocardial infarction (AMI) and 116 healthy controls (age range for both: 30 years to 70 years; both males and females) were randomly selected from the Aga Khan University and National Institute of Cardiovascular Diseases, Karachi with informed consent. The blood samples were obtained and analyzed for ABO blood groups and serum levels of sICAM-1 and sE-selectin using kit methods. Statistical tests including independent sample t-test and Two-way ANOVA were used to study the association of these adhesion molecules with blood groups in AMI patients and healthy controls. Duration of the study was from July 2021 to June 30, 2023.

Results

Mean serum levels of sICAM-1 were significantly higher in AMI patients compared to healthy controls (342±159 mg/dl vs. 227±104 mg/dl; p-value<0.001). Similarly, serum levels of sE-selectin were also significantly higher in AMI patients compared to healthy controls (53.6±26.9 mg/dl vs. 40.7± mg/dl; p-value<0.001). Moreover, mean concentrations of sICAM-1 and sE-selectin for the interaction between subject type (cases and control) and blood groups were statistically significant (p-value = 0.007 and p-value = 0.035, respectively).

Conclusion

There is an association of adhesion molecules, sICAM-1 and sE-selectin with ABO blood groups in Pakistani patients hospitalized with AMI.

O blood type is not associated with worse coagulopathy or outcome in exsanguinating trauma

BACKGROUND

Despite improving understanding of trauma-induced coagulopathy (TIC), mortality and morbidity due to exsanguinating trauma remain high. Increased complications due to hemorrhage have been reported in blood group O, possibly due to reduced levels of von Willebrand factor (vWF).

METHODS

An urban level 1 adult trauma center registry was retrospectively queried. Patients receiving ≥6 units of pRBC within 4 ​h of presentation were included. Patient demographics, admission labs and outcomes were obtained. Univariate and multiple logistic regression analyses were performed.

RESULTS

562 patients were identified. There were no significant differences in demographics, admission labs, or outcome between different ABO groups. After adjustment, Type A patients were more likely to be hypocoagulable compared to Type O patients (p ​= ​0.014). No mortality differences were seen between ABO types in multiple regression analysis.

CONCLUSIONS

No outcome or mortality differences were seen between ABO types, therefore factors other than vWF expression should be considered to explain coagulopathy in trauma patients.

Non-O blood types are associated with a greater risk of large artery atherosclerosis stroke and dysregulation of cholesterol metabolism: an observational study

BACKGROUND

Previous research on ABO blood types and stroke has been controversial, predominantly suggesting heightened risk of stroke in non-O blood types. Nonetheless, investigations into the correlation and underlying mechanisms between ABO blood groups and stroke subtypes, especially within Chinese cohorts, remain limited.

METHODS

The ABO blood types of 9,542 ischaemic stroke (IS) patients were inferred using two ABO gene loci (c.261G > del; c.802G > A). The healthy population was derived from the 1000 Genomes Project. Patients were classified by the causative classification system (CCS). Volcano plot and gene ontology (GO) analysis were employed to explore protein differential expression among blood types. Additionally, HT29 and SW480 cell lines with downregulated ABO expression were generated to evaluate its impact on cholesterol uptake and efflux.

RESULTS

A greater proportion of stroke patients had non-O blood types (70.46%) than did healthy individuals (61.54%). Notable differences in blood type distributions were observed among stroke subtypes, with non-O blood type patients mainly classified as having large artery atherosclerosis (LAA). Clinical baseline characteristics, such as the low-density lipoprotein cholesterol level, activated partial thromboplastin time and thrombin time, varied significantly among blood types. A volcano plot revealed 17 upregulated and 42 downregulated proteins in the O blood type. GO term analysis indicated that downregulated proteins were primarily associated with lipid metabolism pathways. In vitro experiments revealed that reducing ABO gene expression decreased cholesterol uptake and increased cholesterol efflux.

CONCLUSIONS

This study revealed that the non-O blood type increased the risk of LAA stroke through cholesterol metabolism.

Determinants of Variable Total Platelet Count in Healthy Plateletpheresis Donor

The platelet count in a healthy individual varies between 150 and 450 × 109/L. This study explores the factors affecting this variation in platelet count in healthy blood donors selected for platelet donation. This retrospective study comprises an analysis of platelet donor data between the year 2016-2022. The pre-recorded donor details such as age, gender, blood group, body mass index (BMI), and complete blood counts were collected and analyzed using the software 'R' (version 4.1.0). The statistical analysis consists of a test of normalcy followed by descriptive details and advanced statistics such as correlation and regression analysis to predict the variables affecting platelet count. The p-value of less than 0.05 was taken as significant. The median (IQR) of hemoglobin, platelet count, and total leucocyte count (TLC) was 142(135-150) g/L, 239(204-285) × 109/L, and 7.6(6.4-8.8) × 109/L, respectively. The platelet count was positively correlated with TLC (p = 0.000) and negatively with the age of the platelet donor (p = 0.001). The Kruskal-Wallis test detected significant differences in the platelet count among the ABO blood group (p = 0.008). Further, regression analysis confirms the independent positive association of total platelet count with the total leucocyte count (p = 0.000) and the negative association of platelet count with age (p = 0.004). This study concludes the strong dependency of total platelet count with total leucocyte count, age, and blood group.

Association of blood group O with a recurrent risk for acute lower gastrointestinal bleeding from a multicenter cohort study

The relationship between blood group and rebleeding in acute lower gastrointestinal bleeding (ALGIB) remains unclear. This study aimed to investigate the association between blood group O and clinical outcomes in patients with ALGIB. The study included 2336 patients with ALGIB whose bleeding source was identified during initial endoscopy (from the CODE BLUE-J Study). The assessed outcomes encompassed rebleeding and other clinical parameters. The rebleeding rates within 30 days in patients with blood group O and those without blood group O were 17.9% and 14.9%, respectively. Similarly, the rates within 1 year were 21.9% for patients with blood group O and 18.2% for those without blood group O. In a multivariate analysis using age, sex, vital signs at presentation, blood test findings, comorbidities, antithrombotic medication, active bleeding, and type of endoscopic treatment as covariates, patients with blood group O exhibited significantly higher risks for rebleeding within 30 days (odds ratio [OR] 1.31; 95% confidence interval [CI] 1.04-1.65; P = 0.024) and 1 year (OR 1.29; 95% CI 1.04-1.61; P = 0.020) compared to those without blood group O. However, the thrombosis and mortality rates did not differ significantly between blood group O and non-O patients. In patients with ALGIB, blood group O has been identified as an independent risk factor for both short- and long-term rebleeding.

ABO and Rhesus blood groups and multiple health outcomes: an umbrella review of systematic reviews with meta-analyses of observational studies

BACKGROUND

Numerous studies have been conducted to investigate the relationship between ABO and Rhesus (Rh) blood groups and various health outcomes. However, a comprehensive evaluation of the robustness of these associations is still lacking.

METHODS

We searched PubMed, Web of Science, Embase, Scopus, Cochrane, and several regional databases from their inception until Feb 16, 2024, with the aim of identifying systematic reviews with meta-analyses of observational studies exploring associations between ABO and Rh blood groups and diverse health outcomes. For each association, we calculated the summary effect sizes, corresponding 95% confidence intervals, 95% prediction interval, heterogeneity, small-study effect, and evaluation of excess significance bias. The evidence was evaluated on a grading scale that ranged from convincing (Class I) to weak (Class IV). We assessed the certainty of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation criteria (GRADE). We also evaluated the methodological quality of included studies using the A Measurement Tool to Assess Systematic Reviews (AMSTAR). AMSTAR contains 11 items, which were scored as high (8-11), moderate (4-7), and low (0-3) quality. We have gotten the registration for protocol on the PROSPERO database (CRD42023409547).

RESULTS

The current umbrella review included 51 systematic reviews with meta-analysis articles with 270 associations. We re-calculated each association and found only one convincing evidence (Class I) for an association between blood group B and type 2 diabetes mellitus risk compared with the non-B blood group. It had a summary odds ratio of 1.28 (95% confidence interval: 1.17, 1.40), was supported by 6870 cases with small heterogeneity (I2 = 13%) and 95% prediction intervals excluding the null value, and without hints of small-study effects (P for Egger's test > 0.10, but the largest study effect was not more conservative than the summary effect size) or excess of significance (P < 0.10, but the value of observed less than expected). And the article was demonstrated with high methodological quality using AMSTAR (score = 9). According to AMSTAR, 18, 32, and 11 studies were categorized as high, moderate, and low quality, respectively. Nine statistically significant associations reached moderate quality based on GRADE.

CONCLUSIONS

Our findings suggest a potential relationship between ABO and Rh blood groups and adverse health outcomes. Particularly the association between blood group B and type 2 diabetes mellitus risk.

Blood group O is associated with ARDS development but exhibits lower mortality in the intensive care unit - A retrospective multicentre study

Background

Acute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in the intensive care unit (ICU). Previous studies have suggested that blood group A increases the risk of developing ARDS following sepsis and major trauma. This study investigated the association between ABO and Rh blood groups and ARDS development and mortality in ARDS.

Methods

Patients admitted to the ICUs at Skåne University Hospital in Lund and Malmö, Sweden, in 2016 were retrospectively screened for ARDS according to the Berlin definition. Clinical data, patient characteristics, lab results, and survival data were collected from medical records and registry data. In addition, chest radiographs were reviewed by radiologists. ARDS development and 30-day mortality were analysed using multivariable logistic regression.

Results

A total of 1439 ICU patients were included. Of these, 10% had ARDS. Blood group O was associated with an increased risk of having or developing ARDS compared to blood group A (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.13-2.84, p = 0.014). Among ARDS patients, blood group O had decreased 30-day mortality compared to blood group A (OR 0.25, 95% CI 0.09-0.67, p = 0.007). The Rh blood group was not associated with ARDS development or mortality.

Conclusion

In this study of ICU patients, blood group O was associated with an increased risk of having or developing ARDS but a decreased mortality in ARDS compared to blood group A. Further studies are needed to clarify the relationship and underlying mechanisms of the ABO blood group and ARDS.

Incidence and Risk Factor of Hepatocellular Carcinoma Recurrence After Liver Transplant: Results From a Single Clinic

OBJECTIVES

Although liver transplant is highly effective for early-stage hepatocellular carcinoma, guidance on tailored posttransplant management to optimize outcomes is lacking. We examined the incidence and pretransplant radiological scans and indicators of tumor marker associated with posttransplant hepatocellular carcinoma recurrence.

MATERIALS AND METHODS

We reviewed outcomes of 34 hepatocellular carcinoma candidates aged ≥18 years who underwent living-donor liver transplant between January 2016 and January 2023. The primary outcome was biopsy-proven posttransplant hepatocellular carcinoma recurrence at any site. We used Kaplan-Meier analysis to calculate cumulative incidence and Cox regression to identify predictors of posttransplant hepatocellular carcinoma recurrence.

RESULTS

Among 34 transplant candidates, median age was 44 years, 84% had hepatitis C, median laboratory Model for End-Stage Liver Disease score was 18, and median pretransplant α-fetoprotein level was 235 ng/dL. From imaging scans pretransplant, 74% of candidates met Milan criteria. Median wait time to transplant was 67 days, and 23% received pretransplant locoregional therapy. Seven (20.5%) had hepatocellular carcinoma recurrence after median of 1.4 years, with cumulative incidences of 4 (11.7%) and 3 (8.8%) at 1 and 2 years posttransplant. Pretransplant number of lesions (P = .015), largest lesion diameter (P = .008), and higher amount of tumor markers (P = .002) were significant predictors of hepatocellular carcinoma recurrence after adjusting for pretransplant locoregional therapy and wait time. Posttransplant hepatocellular carcinoma recurrence (P < .001) and higher amount of tumor markers (P = .029) were associated with lower posttransplant survival.

CONCLUSIONS

Risk of hepatocellular carcinoma recurrence was significantly associated with the number and size of lesions at the time of livingdonor liver transplant and amount of tumor markers. Risk stratification using a predictive model for posttransplant hepatocellular carcinoma recurrence based on pretransplant imaging and tumor markers may help guide candidate selection and tailoring of hepatocellular carcinoma surveillance strategy after living-donor liver transplant.

Blood type O heart transplant candidates have longer waitlist time and higher delisting under the new allocation system

OBJECTIVE

Prior studies have examined the effect of blood type on heart transplantation (HTx) waitlist outcomes in cohorts through 2015. We aim to analyze the effect of blood type on contemporary waitlist outcomes with a new allocation system focus.

METHODS

Adults listed for HTx between April 2015 and December 2020 were included. Survival to HTx and waitlist death/deterioration was compared between type O and non-type O candidates using competing risks regression. Donor/recipient ABO compatibility trends were further investigated.

RESULTS

Candidates with blood type O (n = 7509) underwent HTx less frequently than candidates with blood type other than type O (n = 9699) (subhazard ratio [sHR], 0.56; 95% CI, 0.53-0.58) with higher rates of waitlist death/deterioration (sHR, 1.18; 95% CI, 1.04-1.34). Subgroup analyses demonstrated persistence of this trend under the new donor heart allocation system (HTx: sHR, 0.58; 95% CI, 0.54-0.62; death/clinical deterioration: sHR, 1.27; 95% CI, 1.02-1.60), especially among those listed at high status (1, 2, or 3) (HTx: sHR, 0.69; 95% CI, 0.63-0.75; death/deterioration: sHR, 1.61; 95% CI, 1.16-2.22). Among those listed at status 3, waitlist death/deterioration was modified by presence of a durable left ventricular assist device (left ventricular assist device: sHR, 1.57; 95% CI, 0.58-4.29; no left ventricular assist device: sHR, 3.79; 95% CI, 1.28-11.2). Type O donor heart allocation to secondary ABO candidates increased in the new system (14.5% vs 12.0%; P < .01); post-HTx survival remained comparable between recipients with blood type O and non-type O (log-rank P = .07).

CONCLUSIONS

Further logistical considerations are warranted to minimize allocation inequity regarding blood type under the new allocation system.

ABO blood types may affect transient neurological events after surgical revascularization in patients with moyamoya disease: a retrospective single center study

BACKGROUND

Moyamoya disease (MMD) is a cerebrovascular disease with unknown cause. Patients with MMD disease usually experience transient neurological events (TNEs) after revascularization surgery. This retrospective single-center study was aimed to explore the risk factors of postoperative TNEs after surgical revascularization in patients with MMD.

METHODS

We selected 324 patients who underwent surgical revascularization between January 2017 and September 2022 in our center. The perioperative characteristics of the patients were recorded and the outcome was TNEs after surgery. An analysis of risk factors contributing to postoperative TNEs by using logistic regression model.

RESULTS

Three hundred twelve patients were enrolled, and the incidence of postoperative TNEs was 34% in our study. Males were more likely to suffer from postoperative TNEs (OR = 2.344, p = 0.002). Preoperative ischemic presentation (OR = 1.849, p = 0.048) and intraoperative hypotension (OR = 2.332, p = 0.002) were associated with postoperative TNEs. Compared to patients with blood type O, patients with blood type A (OR = 2.325, p = 0.028), B (OR = 2.239, p = 0.027) and AB (OR = 2.938, p = 0.019) had a significantly higher incidence of postoperative TNEs. A risk prediction model for postoperative TNEs was established, and the established risk prediction area under the receiver operating characteristic curve (ROC) of the model was 0.741.

CONCLUSIONS

Males, preoperative ischemic presentation and intraoperative hypotension were associated with postoperative TNEs. We also found a possible link between postoperative TNEs and ABO blood types after surgical revascularization for moyamoya patients.

ABO blood type and functional neurological outcome in patients with severe traumatic brain injury

BACKGROUND

The ABO blood system has been involved in the pathogenesis of several diseases, including coagulopathy and bleeding complications. In trauma patients, blood type A has been associated with acute respiratory distress syndrome, and recently, blood type O has been associated with all-cause mortality. The purpose of this study was to assess the association between ABO blood types and long-term functional outcomes in critically ill patients with severe traumatic brain injury (TBI).

METHODS

We conducted a single-center, retrospective, observational study including all patients admitted to the intensive care unit with severe TBI (defined as a Glasgow Coma Scale score of ≤8) between January 2007 and December 2018. Patient characteristics and outcomes were extracted from a prospective registry of all intubated patients admitted to the intensive care unit for TBI. ABO blood types were retrospectively retrieved from patient medical records. The association between ABO blood type (A, B, AB, and O) and unfavorable functional outcome (defined by a Glasgow Outcome Scale score between 1 and 3) 6 months after injury was assessed in univariate and multivariate analysis.

RESULTS

A total of 333 patients meeting the inclusion criteria were included. There were 151 type O (46%), 131 type A (39%), 37 type B (11%), and 12 type AB patients (4%). No significant differences in baseline demographic, clinical, or biological characteristics were observed between blood types. The prevalence of unfavorable outcome was significantly different between the four groups. After adjustment for confounders, blood type O was significantly associated with unfavorable outcome at 6 months (odds ratio, 1.97; confidence interval [1.03-3.80]; p = 0.042). The prevalence of coagulopathy or progressive hemorrhagic injury was not statistically different between blood types ( p = 0.575 and p = 0.813, respectively).

CONCLUSION

Blood type O appears to be associated with unfavorable long-term functional outcome in critically ill patients with severe TBI. Further studies are needed to detail the mechanism underlying this relationship.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Blood group and ischemic stroke, myocardial infarction, and peripheral vascular disease: A meta-analysis of over 145,000 cases and 2,000,000 controls

OBJECTIVE

Cardiovascular illnesses have been associated to ABO blood types, specifically through an effect on von Willebrand factor and factor FVIII levels. We conducted a meta-analysis to comprehensively explore the relationship between blood groups and ischemic stroke, myocardial infarction, and peripheral vascular disease.

MATERIALS AND METHODS

A comprehensive meta-analysis was undertaken to investigate blood groups and ischemic stroke (IS), myocardial infarction (MI) and peripheral vascular disease (PVD). Odds ratios (OR) were used to assess the relationship between blood groups and disease. RevMan v5,4 was used to statistically analyse the results. Risk of bias was assessed using the Newcastle-Ottawa scale.

RESULTS

A total of 72 studies (18 ischemic stroke, 37 myocardial infarction, 17 peripheral vascular disease) met our search criteria, totalling 145,499 cases and 2,113,736 controls. Mean age ranged between 18 and 90 years. Compared to blood group-O, non-O blood group had an increased association with IS (OR=1.13, 95%Cl: 1.07-1.21, P < 0.001), MI (OR=1.17, 95%Cl: 1.11-1.24, P < 0.001) and PVD (OR=1.15, 95%Cl: 1.04-1.28, P=0.005). Compared to blood group-O, blood group A had a stronger statistically significant association to IS (OR=1.19, P=0.001), MI (OR=1.22, P < 0.001) and PVD (OR=1.15, P=0.03). Blood group-B has the lowest risk associated with MI (OR=1.09, P=0.01). In addition, blood groups AB had a stronger statistically significant association to IS (OR=1.24, P=0.01), and MI (OR=1.20, P < 0.001) compared with the other blood groups.

CONCLUSIONS

Compared to blood group-O, groups A and AB are strongly associated to ischemic stroke, myocardial infarction, and peripheral vascular disease.

Genomic approaches to identify and investigate genes associated with atrial fibrillation and heart failure susceptibility

Atrial fibrillation (AF) and heart failure (HF) contribute to about 45% of all cardiovascular disease (CVD) deaths in the USA and around the globe. Due to the complex nature, progression, inherent genetic makeup, and heterogeneity of CVDs, personalized treatments are believed to be critical. To improve the deciphering of CVD mechanisms, we need to deeply investigate well-known and identify novel genes that are responsible for CVD development. With the advancements in sequencing technologies, genomic data have been generated at an unprecedented pace to foster translational research. Correct application of bioinformatics using genomic data holds the potential to reveal the genetic underpinnings of various health conditions. It can help in the identification of causal variants for AF, HF, and other CVDs by moving beyond the one-gene one-disease model through the integration of common and rare variant association, the expressed genome, and characterization of comorbidities and phenotypic traits derived from the clinical information. In this study, we examined and discussed variable genomic approaches investigating genes associated with AF, HF, and other CVDs. We collected, reviewed, and compared high-quality scientific literature published between 2009 and 2022 and accessible through PubMed/NCBI. While selecting relevant literature, we mainly focused on identifying genomic approaches involving the integration of genomic data; analysis of common and rare genetic variants; metadata and phenotypic details; and multi-ethnic studies including individuals from ethnic minorities, and European, Asian, and American ancestries. We found 190 genes associated with AF and 26 genes linked to HF. Seven genes had implications in both AF and HF, which are SYNPO2L, TTN, MTSS1, SCN5A, PITX2, KLHL3, and AGAP5. We listed our conclusion, which include detailed information about genes and SNPs associated with AF and HF.

Comprehensive analysis of platelet glycoprotein Ibα ectodomain glycosylation

BACKGROUND

Platelet glycoprotein (GP) Ibα is the major ligand-binding subunit of the GPIb-IX-V complex that binds von Willebrand factor. GPIbα is heavily glycosylated, and its glycans have been proposed to play key roles in platelet clearance, von Willebrand factor binding, and as target antigens in immune thrombocytopenia syndromes. Despite its importance in platelet biology, the glycosylation profile of GPIbα is not well characterized.

OBJECTIVES

The aim of this study was to comprehensively analyze GPIbα amino acid sites of glycosylation (glycosites) and glycan structures.

METHODS

GPIbα ectodomain that was recombinantly expressed or that was purified from human platelets was analyzed by Western blot, mass spectrometry glycomics, and mass spectrometry glycopeptide analysis to define glycosites and the structures of the attached glycans.

RESULTS

We identified a diverse repertoire of N- and O-glycans, including sialoglycans, Tn antigen, T antigen, and ABO(H) blood group antigens. In the analysis of the recombinant protein, we identified 62 unique O-glycosites. In the analysis of the endogenous protein purified from platelets, we identified 48 unique O-glycosites and 1 N-glycosite. The GPIbα mucin domain is densely O-glycosylated. Glycosites are also located within the macroglycopeptide domain and mechanosensory domain.

CONCLUSIONS

This comprehensive analysis of GPIbα glycosylation lays the foundation for further studies to determine the functional and structural roles of GPIbα glycans.

Impact of ABO Blood Group on Thromboembolic and Bleeding Complications in Patients with Left Ventricular Assist Devices

BACKGROUND

 The ABO blood group system is linked to hemostasis via its relationship with von Willebrand factor (VWF) and factor VIII (FVIII). In the current study, we investigated the association of the ABO system with clinical outcomes as well as VWF and platelet function in patients with left ventricular assist devices (LVADs).

METHODS

 Bleeding and thromboembolic complications were assessed in 111 patients during 1 year after LVAD implantation. In 67 LVAD patients, VWF antigen, VWF activity, VWF ristocetin cofactor, VWF collagen-binding, and FVIII activity were assessed. Platelet surface P-selectin and activated glycoprotein IIb/IIIa were determined by flow cytometry, and soluble P-selectin was measured with an enzyme-linked immunoassay. Platelet aggregation was assessed by light transmission and impedance aggregometry.

RESULTS

 Thirty-six patients (32.4%) experienced a bleeding and 22 patients (19.8%) a thromboembolic event. In univariate analyses, patients with blood group O had numerically more bleeding complications and less thromboembolic events as compared to patients with blood group non-O (both p ≥ 0.05). After multivariable adjustment, blood group O was significantly associated with a higher risk of bleeding (hazard ratio 2.42 [95% confidence interval 1.03-5.70], p = 0.044) but not linked to thromboembolic complications.

CONCLUSION

 Patients with blood group O had significantly lower levels of VWF and FVIII (all p < 0.05), whereas P-selectin expression in response to thrombin-receptor activating peptide and soluble P-selectin were higher as compared to patients with blood group non-O (both p < 0.05). LVAD patients with blood group O are at an increased bleeding risk, potentially due to lower VWF and FVIII levels.

Galectin-3 and Blood Group: Binding Properties, Effects on Plasma Levels, and Consequences for Prognostic Performance

Previous studies have reported an association between ABO type blood group and cardiovascular (CV) events and outcomes. The precise mechanisms underpinning this striking observation remain unknown, although differences in von Willebrand factor (VWF) plasma levels have been proposed as an explanation. Recently, galectin-3 was identified as an endogenous ligand of VWF and red blood cells (RBCs) and, therefore, we aimed to explore the role of galectin-3 in different blood groups. Two in vitro assays were used to assess the binding capacity of galectin-3 to RBCs and VWF in different blood groups. Additionally, plasma levels of galectin-3 were measured in different blood groups in the Ludwigshafen Risk and Cardiovascular Health (LURIC) study (2571 patients hospitalized for coronary angiography) and validated in a community-based cohort of the Prevention of Renal and Vascular End-stage Disease (PREVEND) study (3552 participants). To determine the prognostic value of galectin-3 in different blood groups, logistic regression and cox regression models were used with all-cause mortality as the primary outcome. First, we demonstrated that galectin-3 has a higher binding capacity for RBCs and VWF in non-O blood groups, compared to blood group O. Additionally, LURIC patients with non-O blood groups had substantially lower plasma levels of galectin-3 (15.0, 14.9, and 14.0 μg/L in blood groups A, B, and AB, respectively, compared to 17.1 μg/L in blood group O, p < 0.0001). Finally, the independent prognostic value of galectin-3 for all-cause mortality showed a non-significant trend towards higher mortality in non-O blood groups. Although plasma galectin-3 levels are lower in non-O blood groups, the prognostic value of galectin-3 is also present in subjects with a non-O blood group. We conclude that physical interaction between galectin-3 and blood group epitopes may modulate galectin-3, which may affect its performance as a biomarker and its biological activity.

Prolonged waitlisting is associated with mortality in extracorporeal membrane oxygenation-supported heart transplantation candidates

OBJECTIVE

Heart transplantation (HTx) candidates supported with venoarterial extracorporeal membrane oxygenation (ECMO) may be listed at highest status 1 but are at inherent risk for ECMO-related complications. The effect of waitlist time on postlisting survival remains unclear in candidates with ECMO support who are listed using the new allocation system.

METHODS

Adult candidates listed with ECMO for a first-time, single-organ HTx from October 18, 2018, to March 21, 2021, in the Scientific Registry of Transplant Recipients database were included and stratified according to waitlist time (≤7 vs ≥8 days). Postlisting outcomes were compared between cohorts.

RESULTS

Among 175 candidates waitlisted for ≤7 days, 162 (92.6%) underwent HTx whereas 13 (7.4%) died/deteriorated compared with 41 (57.8%) and 21 (29.6%) of the 71 candidates waitlisted for ≥8 days, respectively (P < .01). Blood type O candidates (odds ratio [OR], 2.94; 95% CI, 1.54-5.61) were more likely to wait ≥8 days whereas candidates with concurrent intra-aortic balloon pump were less likely (OR, 0.30; 95% CI, 0.10-0.89). Obesity was additionally associated among those listed at status 1 (OR, 2.04; 95% CI, 1.00-4.17). Waitlisting for ≥8 days was independently associated with 90-day postlisting mortality conditional on survival to day 8 postlisting (hazard ratio, 5.59; 95% CI, 2.59-12.1). Candidates listed at status 1 showed similar trends (hazard ratio, 5.49; 95% CI, 2.39-12.6). There was no significant difference in 90-day post-HTx survival depending on whether a candidate waited for ≥8 days versus ≤7 days (92.7 vs 92.0%; log rank P = .87).

CONCLUSIONS

Among ECMO-supported candidates, obtaining HTx within 1 week of listing might improve overall survival.

Role of the ABO Blood Groups as a Risk Factor for Retinal Vein Occlusion

INTRODUCTION

A recent study suggested that non-O blood groups had an increased risk for the presence of retinal vein occlusion (RVO). In this study, we investigated (i) an association between blood group and the presence of RVO and (ii) whether this association correlated to other RVO risk factors.

METHODS

We included 485 RVO patients and 295 control subjects who were recruited in this case-control study. We determined ABO genotypes rs8176719 as a marker for the O allele and rs8176746 for the B allele by polymerase chain reaction.

RESULTS

We did not find an association between ABO blood group and the presence of RVO. In detail, the proportion of ABO blood groups was similar among RVO patients and control subjects (p = 0.527). In a logistic regression, non-O blood group was associated with 1.06-fold higher odds of being a RVO patient (95% CI: 0.78-1.45, p = 0.693), and this lack of association prevailed upon multivariable adjustment for age, gender, history of stroke and venous thromboembolism, and co-medication with lipid-lowering agents.

DISCUSSION

Although non-O blood groups are a known risk factor for thrombotic and cardiovascular disease, they do not seem to be a major risk factor for the development of RVO.

Lower Levels of ABO Anti-A and Anti-B of IgM, IgG and IgA Isotypes in the Serum but Not the Saliva of COVID-19 Convalescents

Individuals with ABO type O, naturally possessing anti-A and anti-B antibodies in their serum, are underrepresented among patients infected with SARS-CoV-2 compared with healthy controls. The ABO antibodies might play a role in the viral transmission. Therefore, we aimed to quantify anti-A/anti-B, including their subclasses IgM, IgG and IgA, in the serum and saliva of Caucasians (n = 187) after mild COVID-19 to compare them with individuals who had never been infected with SARS-CoV-2. Two samples were collected within two months after the diagnosis (median days: 44) and two months later. ABO antibodies were determined by flow cytometry. Additionally, total IgA in saliva and antibodies specific to SARS-CoV-2 were tested by ELISA. COVID-19 convalescents had significantly lower levels of anti-A/anti-B IgM, IgG and IgA in their serum than control subjects (p < 0.001). Interestingly, no significant differences were observed in saliva. ABO antibody levels remained stable over the period considered. No relation of ABO to the level of SARS-CoV-2-specific antibodies was observed. Total IgA was lower in convalescents than in controls (p = 0.038). Whereas ABO antibodies in the saliva may not contribute to the pathogenesis of COVID-19, individual pre-existing high serum concentrations of anti-A/anti-B may have a protective effect against SARS-CoV-2 infection.

Association of IgE elevation with blood group in COVID-19 patients

Aim : All parameters that are thought to be efficient in getting sick and follow-up of the disease should be investigated because of COVID-19 disease has serious consequences. The aim of this study was to investigate whether there is a relationship between the AB0 blood group with Rh factor systems and the frequency of catching COVID-19 infection and between IgE elevation according to blood groups and COVID-19 positivity. Material and Method: Blood groups and IgE levels of the control group (2690 patients) were compared retrospectively with 7300 patients who were admitted to our hospital between March 10, 2020, and March 31, 2021, and confirmed as COVID-19 positive with viral ribonucleic acid reverse transcriptase-polymerase chain reaction (RT-PCR). Results: It was found that among the blood groups, the highest COVID-19 positivity belonged to the A blood group (46.17%) and the lowest belonged to the AB blood group (9.04%). The increase in IgE elevation was found statistically significant in COVID-19 positive patients (P

ABO Blood Type Is Associated with Thrombotic Risk in Patients with Nonvalvular Atrial Fibrillation

Blood type is reportedly correlated with the occurrence of cardiovascular diseases, presumably because of its effect on thrombogenicity. However, the relationship between blood type and thrombotic complications in atrial fibrillation (AF) remains unclear. This retrospective study analyzed the blood types of 1170 AF patients (mean age, 70 years; 58% men) who were followed up for up to 4 years. Patients with greater than mild mitral stenosis or prosthetic valves were excluded. The cohort included 305 (26%) type O, 413 (35%) type A, 333 (28%) type B, and 119 (10%) type AB patients. The primary endpoint of major adverse cerebrovascular events (MACE) occurred in 52 (4.4%) patients. When longitudinal outcomes were plotted, AB blood type patients had worse prognosis than non-AB blood type patients (p = 0.039), particularly type O blood patients (p = 0.049). Multivariate Cox regression analysis revealed that AB blood type was associated with higher MACE rates (adjusted hazard ratio, 2.01; 95% confidence interval, 1.01–4.00; p = 0.048) than non-AB blood types independent of anticoagulation therapy duration or CHA2DS2-VASc score. These indicate that AF patients with AB blood type are at an increased risk of MACE compared to those with non-AB blood type independent of the duration of anticoagulation or the CHA₂DS₂-VASc score.

ABO and Rh blood groups, demographics, and comorbidities in COVID-19 related deaths: A retrospective study in Split-Dalmatia County, Croatia

Background

Blood group phenotypes have been associated with COVID-19 susceptibility and severity. This study aimed to examine ABO/Rh blood group distribution in COVID-19-related deaths considering demographics and pathological conditions.

Methods

We conducted a retrospective study at the University Hospital Center Split, Croatia, that included 245 COVID-19 positive individuals that died from April 8, 2020, to January 25, 2021. We extracted data on their blood groups, demographics, and pre-existing comorbidities and compared findings with general population data from blood group donations (n = 101,357) and non-COVID-19 deaths from 2019 (n = 4968).

Results

The proportion of dead males was significantly higher than in non-COVID-19 cases (63.7% vs. 48.9%, P < 0.001), while the proportion of older individuals did not differ. The prevailing pre-existing diseases were hypertension (59.6%), diabetes (37.1%), heart failure (28.8%), digestive disorder (26.5%), and solid tumor (21.6%). The ABO distribution in the deceased and donors' group showed significant differences, with the higher prevalence of A/AB group and lower prevalence of 0, but with individual differences significant only for AB and non-AB groups. There was a reduced proportion of females within the deceased with group 0 (P = 0.014) and a higher proportion of AB individuals with coronary heart disease (P = 0.024).

Conclusion

The study confirmed a higher risk of death in males. The lower proportion of type 0 in deceased individuals was greater in females, implying that group 0 is not necessarily an independent protective factor. Coronary heart disease was identified as a potential risk factor for AB individuals.

Detection of five common variants of ABO gene by a triplex probe-based fluorescence-melting-curve-analysis

Current studies have suggested that the ABO blood group system is associated with several clinical conditions. For large-scale genotyping of ABO alleles, we developed a triplex fluorescence melting curve analysis (FMCA) to determine five single nucleotide variants (SNVs), c.261delG, c.796C>A, c.802G>A and c.803G>C and c.1061delC, responsible for common ABO phenotypes using dual-labeled self-quenched (TaqMan) probes in a single tube. We accurately determined c.796C>A, c.802G>A, and c.803G>C genotypes using a FAM-labeled probe, c.261delG using a CAL Fluor Orange 560- labeled probe, and c.1061delC using a Cy5-labeled probe. The present genotyping results of five SNVs in 214 subjects of the 1000 Genomes Project were in full agreement with those of the database sequence. The predicted ABO phenotypes using combinations of these five SNVs by this method in 288 Japanese subjects were in complete agreement with those by hemagglutination assay, although we did not find any A2 (alleles containing c.1061delC) or O.02 (alleles containing c.802G>A) alleles. The present triplex probe-based FMCA is a valid and credible method for a considerably accurate large-scale determination of ABO allele genotypes and estimation of phenotypes.

ABO blood group is not a predictive factor for the amount of early opioid consumption in postanesthesia care unit: a prospective cohort study in 3,316 patients

Background

Immediate postoperative pain in the postanesthesia care unit (PACU) is common. Titration of opioid is the most popular strategy for controlling early postoperative pain. ABO blood group has been found to be associated with pain perception. We aimed to find the factors including ABO blood group for predicting the amount of opioid requirement in PACU.

Methods

This prospective cohort study was performed in 3316 patients who underwent various kinds of anesthetic techniques and received immediate postoperative care in PACU. Preoperative, intraoperative and PACU data were collected. A directed acyclic graph (DAG) representing the hypothesized causal pathways of preoperative, intraoperative and PACU data were compiled prior to conducting multinomial logistic regression analysis. Statistical significance in all models was defined as a P-value < 0.05.

Results

Female sex, body mass index, preoperative use of gabapentin, preoperative anxiety score, anesthetic techniques, type of operation, amount of consumed intraoperative opioids, intraoperative use of paracetamol, parecoxib and ondansetron, duration of anesthesia and surgery, amount of blood loss, pain upon PACU arrival, use of paracetamol and parecoxib in PACU were found to be factors influencing amount of opioid consumption in PACU. ABO blood group was not associated with early postoperative opioid requirement.

Conclusions

A significant number of factors are related to amount of opioid requirement in PACU. Some factors can be adjusted to provide better pain relief in early postoperative period. However, ABO blood group is not identified to be a predictive factor for early postoperative opioid consumption in PACU.

Blood Group O Protect End-Stage Renal Disease Patients With Dialysis From Coronary Artery Disease

Objective

Our study aims to investigate the role of the ABO blood group in the development and severity of coronary artery disease (CAD) in end-stage renal disease (ESRD) patients with dialysis.

Methods

A total of 408 ESRD patients with dialysis between January 2010 and December 2020 were enrolled including 204 patients diagnosed with CAD undergoing coronary angiography for the first time, and baseline characteristics as well as Gensini score (GS) were collected. Logistic regression analysis and linear regression analysis were performed to evaluate the relation of ABO blood types to the risk and severity of CAD, respectively.

Results

Blood group O frequency was significantly low in dialysis ESRD patients with CAD (25 vs. 38.24%) compared with the non-CAD patients and multivariable logistic regression showed blood group O was negatively associated with the risk of CAD [adjusted odds ratio (OR) = 0.33, 95% CI = 0.19–0.60, p < 0.001] as well as the GS tertiles (adjusted OR = 0.23, 95% CI = 0.11–0.49, p < 0.001) compared with A blood group. Blood group A, B, and AB were positively associated with the high Gensini tertile compared with O blood group (adjusted OR = 4.26, 95% CI = 2.03–8.93, p < 0.001; adjusted OR = 2.39, 95% CI = 1.11–5.13, p < 0.05; adjusted OR = 4.33, 95% CI = 1.40–13.35, P < 0.05). Similarly, multivariable linear regression results revealed O blood type was negatively associated with the GS (β = −26.129, 95% CI = −40.094 to −12.164, p < 0.001).

Conclusion

This case-control study demonstrated that blood group O was a potential independent protective factor for the risk and severity of CAD in ESRD patients with dialysis.

An Updated Review on the Role of Single Nucleotide Polymorphisms in COVID-19 Disease Severity: A Global Aspect

Abstract:

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and recently has become a serious global pandemic. Age, gender, and comorbidities are known to be common risk factors for severe COVID-19 but are not enough to fully explain the magnitude of their effect on the risk of severity of the disease. Single nucleotide polymorphisms (SNPs) in several genes have been reported as a genetic factor contributing to COVID-19 severity. This comprehensive review focuses on the association between SNPs in four important genes and COVID-19 severity in a global aspect. We discuss a total of 39 SNPs in this review: five SNPs in the ABO gene, nine SNPs in the angiotensin-converting enzyme 2 (ACE2) gene, 19 SNPs in the transmembrane protease serine 2 (TMPRSS2) gene, and six SNPs in the toll-like receptor 7 (TLR7) gene. These SNPs data could assist in monitoring an individual's risk of severe COVID-19 disease, and therefore personalized management and pharmaceutical treatment could be planned in COVID-19 patients.

ABO blood group and skin cancers

Beside the role of ABO group in immunohaematology, there is accumulating evidence that the ABO blood group also plays a key role in various human disorders. The interest in blood groups and their association with disease stems from the awareness that blood group antigens are incredibly important components in the process of cell maturation and control. Studies have indicated a link between cancer and the ABO blood group. The appearance or disappearance of blood type antigens is now considered a hallmark of malignancy in many common cancers. Several tumour markers are in fact known blood group antigens. The aim of this review is to describe the history and possible functions of the ABO group and then summarize the association between blood groups and skin cancers.

Identification and replication of novel genetic variants of ABO gene to reduce the incidence of diseases and promote longevity by modulating lipid homeostasis

Genes related to human longevity have not been studied so far, and need to be investigated thoroughly. This study aims to explore the relationship among ABO gene variants, lipid levels, and longevity phenotype in individuals (≥90yrs old) without adverse outcomes. A genotype-phenotype study was performed based on 5803 longevity subjects and 7026 younger controls from the Chinese Longitudinal Healthy Longevity Survey (CLHLS). Four ABO gene variants associated with healthy longevity (rs8176719 C, rs687621 G, rs643434 A, and rs505922 C) were identified and replicated in the CLHLS GWAS data analysis and found significantly higher in longevity individuals than controls. The Bonferroni adjusted p-value and OR range were 0.013-0.020 and 1.126-1.151, respectively. According to the results of linkage disequilibrium (LD) analysis, the above four variants formed a block on the ABO gene (D’=1, r²_range = 0.585-0.995). The carriers with genotypes rs687621 GG, rs643434 AX, or rs505922 CX (p_range = 2.728 x 10^-107-5.940 x 10^-14; OR_range = 1.004-4.354) and haplotype CGAC/XGXX (p = 2.557 x 10^-27; OR = 2.255) had a substantial connection with longevity, according to the results of genetic model analysis. Following the genotype and metabolic phenotype analysis, it has been shown that the longevity individuals with rs687621 GG, rs643434 AX, and rs505922 CX had a positive association with HDL-c, LDL-c, TC, TG (p_range = 2.200 x 10^-5-0.036, OR_range = 1.546-1.709), and BMI normal level (p_range = 2.690 x 10^-4-0.026, OR_range = 1.530-1.997). Finally, two pathways involving vWF/ADAMTS13 and the inflammatory markers (sE-selectin/ICAM1) that co-regulated lipid levels by glycosylation and effects on each other were speculated. In conclusion, the association between the identified longevity-associated ABO variants and better health lipid profile was elucidated, thus the findings can help in maintaining normal lipid metabolic phenotypes in the longevity population.

ABO Blood Group Differentials on Survival in Hepatocellular Carcinoma Patients Treated with Chemoembolization

BACKGROUND

The association between ABO blood group and the prognosis of hepatocellular carcinoma (HCC) remains unclear. We investigated the impact of ABO blood groups as a prognostic factor in HCC patients treated with transarterial chemoembolization (TACE).

MATERIALS AND METHODS

We revisited records of all HCC patients who underwent TACE between January 2007 and December 2019 at a tertiary care hospital. The inclusion criteria were HCC patients, Child-Pugh score A5-B7, and treated with TACE monotherapy. The baseline characteristics of each patient were compared against their blood group and the survival analysis was carried out using Cox's regression. With Bonferroni adjustment for multiple comparisons, P-values <.0125 were considered statistically significant.

RESULTS

Of 211 eligible patients, the frequencies of blood groups O, A, B, and AB were 89, 54, 56, and 12, respectively. Their respective months of median survival were 41, 20, 21, and 42. After adjustments in the six-and-twelve criteria and Child-Pugh scores, and using blood group O as the referent group, the coefficients (SE) of groups A, B, and AB were 0.69 (0.24), 0.47 (0.23), and 0.49 (0.49), respectively. A significant difference in survival was found only between patients with blood group O vs A (hazard ratio, 2.00; confidence interval, 1.25-3.21).

CONCLUSIONS

ABO blood group is associated with the prognosis of HCC patients treated with TACE monotherapy. In our data, patients with blood group O tended to have the best survival. However, only blood group A patients had a significantly shorter survival rate comparing to blood group O.

ABO blood groups and risk of human immunodeficiency virus infection: A systematic review and meta-analysis

The last few decades have seen a pandemic of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), which continues to cause substantial morbidity and mortality. ABO blood groups are anthropological and genetic characteristics of a population whose associations with HIV infection are still controversial. This systematic review with meta-analysis was undertaken to investigate whether certain blood groups may have associations with HIV infection. PubMed, Scopus and Web of Science databases were systematically searched as of 6 September 2021. Grey literature was identified through screening Google Scholar, and reference lists of relevant studies. All observational studies providing data on ABO blood group distribution among HIV-infected and uninfected participants were included. Using a random effect model, risk ratios (RR) and 95% confidence intervals (CIs) were pooled to quantify this relationship. Fifty eligible studies with a total of 3,068,244 participants and 6508 HIV-infected cases were included. The overall analysis found that blood group AB increased the risk of HIV infection by 19% as compared with non-AB blood groups (RR = 1.19, 95% CI: 1.03-1.39, p = 0.02). Pooled estimates for other blood groups failed to reach statistical significance. Subgroup analyses identified a positive relationship between AB blood group and HIV infection within Asia, patient populations (as opposed to blood donors and general populations), studies with lower sample sizes, high-income countries and studies with a moderate quality score. The sequential omission and re-analysis of studies within sensitivity analyses produced no change in the overall pooled effect. In conclusion, this study identified that blood group AB carriers were more susceptible to HIV infection. Future investigations should be directed toward clarification of the exact role of ABO blood groups in HIV infection and the possible underlying mechanisms.

ABO Blood Group and the Risk of Esophageal Squamous Cell Carcinoma in Kashmir, a High Risk Region

BACKGROUND

ABO blood group has been linked with a number of diseases including cancer. Association of ABO blood type with esophageal squamous cell carcinoma (ESCC) has been sparsely reported and the results are inconsistent. We undertook this study to analyze if any association exists between the ABO and Rh blood groups and ESCC risk.

METHODS

We conducted a hospital-based case control study to analyze ABO and Rh blood groups in patients with histologically proven diagnosis of ESCC and compared them with healthy donors from the same population. ABO and Rh blood group status of general population was obtained from the blood bank at Sher-i-Kashmir Institute of Medical Sciences (SKIMS) and from original articles published from time to time. Chi-Square test was performed to look for statistical significance.

RESULTS

For this study, 206 patients were prospectively enrolled. Seventy-four (35.9%) patients had blood group O. Blood groups type A and type B was found each in 59 (28.6%) patients. In 108,014 healthy donors, 35.3% had blood type O followed by type B (33.66%). There was no significant difference in any of the blood types between patients with ESCC and donors (P = 0.31).

CONCLUSION

No association exists between ABO blood type and the risk of ESCC.

Lewis and ABO histo-blood types and the secretor status of patients hospitalized with COVID-19 implicate a role for ABO antibodies in susceptibility to infection with SARS-CoV-2

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) targets the respiratory and gastric epithelium, causing coronavirus disease 2019 (COVID-19). Tissue antigen expression variations influence host susceptibility to many infections. This study aimed to investigate the closely linked Lewis (FUT3) and ABO histo-blood types, including secretor (FUT2) status, to infections with SARS-CoV-2 and the corresponding severity of COVID-19.

STUDY DESIGN AND METHODS

Patients (Caucasians, n = 338) were genotyped for ABO, FUT3, and FUT2, and compared to a reference population of blood donors (n = 250,298). The association between blood types and severity of COVID-19 was addressed by dividing patients into four categories: hospitalized individuals in general wards, patients admitted to the intensive care unit with and without intubation, and deceased patients. Comorbidities were considered in subsequent analyses.

RESULTS

Patients with blood type Lewis (a-b-) or O were significantly less likely to be hospitalized (odds ratio [OR] 0.669, confidence interval [CI] 0.446-0.971, OR 0.710, CI 0.556-0.900, respectively), while type AB was significantly more prevalent in the patient cohort (OR 1.519, CI 1.014-2.203). The proportions of secretors/nonsecretors, and Lewis a+ or Lewis b+ types were consistent between patients and controls. The analyzed blood groups were not associated with the clinical outcome as defined.

DISCUSSION

Blood types Lewis (a-b-) and O were found to be protective factors, whereas the group AB is suggested to be a risk factor for COVID-19. The antigens investigated may not be prognostic for disease severity, but a role for ABO isoagglutinins in SARS-CoV-2 infections is strongly suggested.

The Association Between ABO Blood Type and Mortality Among Severely Injured Trauma Patients

BACKGROUND

Prior research has reported an association among trauma patients between blood type O and adverse events. More recently, another study reported that severely injured trauma patients of mostly O Rh positive blood type were more likely to die.

OBJECTIVE

The objective of the current study is to examine whether the same increased association is observed for blood type O severely injured patients in a more generalizable population comprised of Rh positive and Rh negative individuals.

METHODS

Patients admitted to a Level-I academic trauma center between 2015 and 2018 with severe injury (Injury Severity Score >15) were included in this retrospective cohort study. Logistic regression estimated odds ratios (ORs) and 95% confidence intervals (CIs) for the association between blood type and mortality.

RESULTS

Among 3,913 patients, a majority were either blood type O (47.5%) or A (34.7%) and 60% were Rh positive. There was no observed difference in complication rates by blood type, and there was no observed significant association with death overall or by cause of death. There were weak, increased associations for blood type B (OR 1.61, 95% CI 0.74-3.53) and type O (OR 1.57, 95% CI 0.90-2.76) compared with blood type A patients.

CONCLUSION

Contrary to prior research, the current results suggest no association between blood type and mortality among severely injured trauma patients.

The association of ABO blood groups and trauma outcomes: A retrospective analysis of 3779 patients

Background:

There is currently a lack of understanding regarding the link between ABO blood types with outcomes of traumatically injured patients. The purpose of this study was to determine the association of ABO blood types with outcomes in traumatically injured patients separated by injury type.

Methods:

This retrospective study evaluated trauma patients at an urban, Level 1 trauma center from January 1, 2017, through December 31, 2017. Patients were excluded if they were pregnant or <16 years old. Recorded outcomes included: ABO blood group, mortality, Injury Severity Score (ISS), race, injury type, mechanism of injury, and complications. Data analysis was performed using descriptive statistics including Chi-squared, Kruskal–Wallis, and F-test calculations.

Results:

A total of 3779 patients were included in this study. No significant differences were present in mean age or ISS between blood types. In patients with penetrating injuries, blood type O was associated with a significant increase in mortality (P = 0.017), red blood cell transfusion (P = 0.027), and massive transfusion protocol (MTP) (P = 0.026) compared to non-O blood types. In patients with blunt injuries, blood type AB was associated with a significant increase in mortality rate compared to non-AB blood types (P = 0.03).

Conclusion:

ABO blood type is connected with an underlying process which affects trauma outcomes, including mortality. Blood type O is associated with increased blood transfusion, MTP, and mortality during the initial hospitalization following a traumatic penetrating injury, while blood type AB is associated with increased mortality during the initial hospitalization following a blunt traumatic injury.

ABO / Rh-D Blood types and susceptibility to Corona Virus Disease-19 in Peshawar, Pakistan

OBJECTIVES

To determine the association between ABO/Rh-D blood types and susceptibility to SARS-CoV-2 infection in Pakistan.

METHODS

In this cross-sectional study, 1935 confirmed cases of COVID-19 were included using consecutive sampling. Age and gender-matched sample of 1935 blood donors was used as a comparison group. Chi-square test and binary logistic regression were used for inferential statistics.

RESULTS

Significantly higher proportion of blood type-B was observed in COVID-19 group (35.9% vs 31.9%, p=0.009). Blood type-AB was found more frequently (14.2% vs 11.8%, p=0.03) in the comparison group. The Rh-D Positive blood types were 93.3% in COVID-19 group and 94.9% in comparison group (p=0.03). The odds of blood type-B, AB and Rh-D positive to test positive for SARS-CoV-2 were 1.195 (95% CI 1.04 - 1.36, p=0.009), 0.80 (95% CI 0.66 - 0.97, p=0.03) and 0.75 (95% CI 0.57- 0.98, p = 0.03), respectively. Blood types A and O did not have significant association with SARS-CoV-2 PCR result (p = 0.22 and 0.88, respectively).

CONCLUSIONS

There is significant association between blood types B & AB and susceptibility to COVID-19. There is no association between blood types A and O with COVID-19. Rh- D positive blood types are less susceptible to COVID-19.

Non-O blood group is associated with lower risk of in-hospital mortality in non-surgically managed patients with type A aortic dissection

BACKGROUND

The association between different ABO blood groups and mortality of aortic dissection (AD) remains controversial. This study aimed to examine whether different ABO blood groups affect the prognosis of AD.

METHODS

Demographic and clinical data were collected from 877 patients diagnosed with AD from 2015 to 2019 in the First Affiliated Hospital of Shantou University Medical College. The association between in-hospital mortality of AD patients and ABO blood group was analyzed using Cox proportional hazards regression models.

RESULTS

This retrograde cohort study demonstrated that for 877 patients, male gender, non-O blood group, Stanford type B AD (TBAD), higher presenting systolic and diastolic blood pressure, and being a recipient of aortic arch replacement surgery (surgery) or endovascular stent-graft implantation (stent-graft) were associated with decreased in-hospital mortality of AD. In Cox proportional hazards models, non-O blood group was associated with lower risk of early mortality regardless of adjustment (HR = 0.668, 95% confidence interval [CI] 0.473-0.944 before adjustment, HR = 0.662, 95% CI 0.468-0.935 after adjustment for age and sex, and HR = 0.641, 95% CI 0.453-0.906 after adjustment for AD types, SBP and surgery). Further analyses revealed that for patients diagnosed with type A AD (TAAD), non-O blood group renders a significant 34.3% decrease in the risk of in-hospital mortality compared with blood group O. Specifically, this difference in mortality risk was found among TAAD patients who did not undergo surgery (HR = 0.579, 95% CI 0.377-0.889), rather than those who did. There was no significant difference in early mortality for patients with TBAD, whether or not stent-grafts were implanted.

CONCLUSIONS

Non-O blood type decreases the risk of in-hospital mortality, especially for TAAD, in AD patients without surgical intervention. More attention must be paid to blood type O TAAD patients without surgical interventions, and early surgical intervention may be an effective means to decrease in-hospital mortality of TAAD.

Blood Type Is Not Associated with Changes in Cardiometabolic Outcomes in Response to a Plant-Based Dietary Intervention

BACKGROUND

Risk of cardiovascular disease is lower in individuals with blood type O and increased in individuals with blood type A, compared with those in other blood groups. However, little evidence is available regarding whether individuals with different blood types benefit from different diet recommendations.

OBJECTIVE

As part of a larger intervention trial using a low-fat vegan diet, this study ascertained whether changes in cardiometabolic outcomes were associated with ABO blood type.

DESIGN

A secondary analysis among intervention-group participants in a 16-week randomized clinical trial.

PARTICIPANTS/SETTING

In a larger study of overweight individuals randomly assigned to follow a low-fat vegan diet or to make no diet changes for 16 weeks, ABO blood typing was conducted on 68 intervention-group participants.

INTERVENTION

Intervention-group participants were asked to follow a low-fat vegan diet and attend weekly educational classes to aid in diet adherence.

MAIN OUTCOME MEASURES

Body weight, fat mass, visceral fat volume, blood lipid levels, fasting plasma glucose levels, and glycated hemoglobin concentrations.

STATISTICAL ANALYSES PERFORMED

Student t tests compared participants with blood type A to all other participants, and individuals with blood type O to all other participants.

RESULTS

There were no significant differences in any outcome between individuals of blood type A and all other participants, or between individuals of blood type O and all other participants. Mean body weight change was -5.7 kg for blood type A participants and -7.0 kg for all other participants (P = 0.09), and was -7.1 kg for type O participants and -6.2 kg for all other participants (P = 0.33). Mean total cholesterol decreased 17.2 mg/dL in the type A group and 18.3 mg/dL for all other participants (P = 0.90), and decreased 17.4 mg/dL among type O participants and 18.4 mg/dL for all other participants (P = 0.89).

CONCLUSIONS

Blood type was not associated with the effects of a plant-based diet on body weight, body fat, plasma lipid concentrations, or glycemic control.

Identifying Genetic and Biological Determinants of Race-Ethnic Disparities in Stroke in the United States

In the United States, causes of racial differences in stroke and its risk factors remain only partly understood, and there is a long-standing disparity in stroke incidence and mortality impacting Black Americans. Only half of the excess risk of stroke in the United States Black population is explained by traditional risk factors, suggesting potential effects of other factors including genetic and biological characteristics. Here, we nonsystematically reviewed candidate laboratory biomarkers for stroke and their relationships to racial disparities in stroke. Current evidence indicates that IL-6 (interleukin-6), a proinflammatory cytokine, mediates racial disparities in stroke through its association with traditional risk factors. Only one reviewed biomarker, Lp(a) (lipoprotein[a]), is a race-specific risk factor for stroke. Lp(a) is highly genetically determined and levels are substantially higher in Black than White people; clinical and pharmaceutical ramifications for stroke prevention remain uncertain. Other studied stroke risk biomarkers did not explain racial differences in stroke. More research on Lp(a) and other biological and genetic risk factors is needed to understand and mitigate racial disparities in stroke.

Association of ABO blood groups and non-culprit plaque characteristics in acute coronary syndrome: an optical coherence tomography study

Background

Cardiovascular disease (CVD) poses a serious threat to human health. Research shows that ABO blood groups, especially non-O blood types, are closely related to the incidence of cardiovascular diseases (CVDs). This study aimed to determine the associations of blood types with non-culprit coronary plaque characteristics using optical coherence tomography (OCT).

Methods

A total of 257 acute coronary syndrome (ACS) patients (average age, 59.39±10.08 years, 80% male) who underwent OCT of 3 vessels were identified. Subjects were divided into 2 groups: the O blood group (71 patients with 121 plaques) and the non-O group (186 patients with 329 plaques). The non-culprit coronary plaque features of the two groups were compared using OCT.

Results

The non-type O group had larger lipid arcs, thinner fibrous caps, and a greater number of thin-cap fibro atheromas (TCFAs). The type A, B, and AB blood groups had larger lipid arcs than the type O blood group, as well as thinner fibrous caps and more TCFAs. The type A blood group had thinner fibrous caps and a greater number of TCFAs than the type B and AB blood groups.

Conclusions

ACS patients with type non-O blood had more non-culprit plaques. Patients with type A blood, in particular, had more vulnerable characteristics than those with type O blood.

Association of ABO blood types with ST resolution following thrombolysis in acute ST elevation myocardial infarction

Introduction: There is paucity of data about the possible role of ABO antigen in response to pharmacologic reperfusion therapy in ST-segment elevation myocardial infarction (STEMI) and its relationship with ST segment recovery; thus, we aimed to evaluate the association of ABO antigen with ST-segment resolution in STEMI patients treated with thrombolysis.

Methods: This prospective and observational study was conducted between March 2016 and September 2017 on patients with first acute STEMI within the first 12 hours after onset of symptoms treated with thrombolysis. Myocardial reperfusion success was determined by single-lead ST-segment recovery in 12-lead ECG. Patients were considered as responders if ST-segment resolved ≥50% or were assigned as non-responders if ST-segment resolution was <50%. Univariable and multivariable analyses were performed to examine the contribution of "A" and "B" blood group antigens to ST-segment resolution and the occurrence of major adverse cardiovascular or cerebrovascular event (MACCE). Odds ratio (OR) with 95% confidence interval (CI) were reported for each variable.

Results: In this study 303 patients (187 males and 116 females) with a mean age of 56.6 ± 16.8 (ranging from 39 to 87 years) were enrolled. 184 patients (60.7%) were responders and 119 patients (39.2%) were non-responders. The presence of either A (4.5 folds increase) or B (5.4 folds increase) antigen was associated with a higher likelihood of a response to thrombolytic therapy, while had not effect on the occurrence of MACCE.

Conclusion: We conclude that the presence of A or B blood group antigens is associated with a better response to thrombolytic therapy in patients with acute STEMI. This finding may imply a higher likelihood for thrombotic occlusion of coronary arteries in patients who have either A or B antigen in their blood.