Associations of ABO and Rhesus D blood groups with phenome-wide disease incidence: A 41-year retrospective cohort study of 482,914 patients.

Background: Whether natural selection may have attributed to the observed blood group frequency differences between populations remains debatable. The ABO system has been associated with several diseases and recently also with susceptibility to COVID-19 infection. Associative studies of the RhD system and diseases are sparser. A large disease-wide risk analysis may further elucidate the relationship between the ABO/RhD blood groups and disease incidence. Methods: We performed a systematic log-linear quasi-Poisson regression analysis of the ABO/RhD blood groups across 1,312 phecode diagnoses. Unlike prior studies, we determined the incidence rate ratio for each individual ABO blood group relative to all other ABO blood groups as opposed to using blood group O as the reference. Moreover, we used up to 41 years of nationwide Danish follow-up data, and a disease categorization scheme specifically developed for diagnosis-wide analysis. Further, we determined associations between the ABO/RhD blood groups and the age at the first diagnosis. Estimates were adjusted for multiple testing. Results: The retrospective cohort included 482,914 Danish patients (60.4% females). The incidence rate ratios (IRRs) of 101 phecodes were found statistically significant between the ABO blood groups, while the IRRs of 28 phecodes were found statistically significant for the RhD blood group. The associations included cancers and musculoskeletal-, genitourinary-, endocrinal-, infectious-, cardiovascular-, and gastrointestinal diseases. Conclusions: We found associations of disease-wide susceptibility differences between the blood groups of the ABO and RhD systems, including cancer of the tongue, monocytic leukemia, cervical cancer, osteoarthrosis, asthma, and HIV- and hepatitis B infection. We found marginal evidence of associations between the blood groups and the age at first diagnosis. Funding: Novo Nordisk Foundation and the Innovation Fund Denmark.

Association of blood group with COVID-19 disease susceptibility and severity in Saudi Arabia.

BACKGROUND: Novel SARS-CoV-2 (COVID-19) virus has rapidly spread worldwide and was declared a pandemic, making identifying and prioritizing individuals most at risk a critical challenge. The literature describes an association between blood groups and the susceptibility to various viral infections and their severity. Knowing if a specific blood group has more susceptibility to COVID-19 may help improve understanding the pathogenesis and severity of the disease. We aimed to assess the association between ABO/RhD and COVID-19 susceptibility and severity, and to compare results with similar studies in Saudi Arabia. STUDY DESIGN AND METHODS: This study was conducted between March and October 2021 on 600 patients confirmed positive for COVID-19 infection. Patients' data were collected and analyzed. As a control, 8423 healthy blood donors were enrolled as a sample representative of the population for blood group distribution. RESULTS: More individuals had blood group B in the COVID-19 group in comparison with the control group (24.2% vs. 18%), The opposite was observed among individuals of group O (39.5% vs. 47.3%). The B blood group was predictive of higher risk of mortality. No significant difference in the distribution of RhD was observed between the COVID-19 and the control groups. Neither ABO nor RhD was significantly associated with the severity of COVID-19. DISCUSSION: Although there was no significant association with the disease severity, the B blood group may be associated with a higher risk for COVID-19 infection. Further studies with a larger sample size are necessary to evaluate this correlation.

The association between different blood group systems and susceptibility to COVID-19: a single center cross-sectional study from Saudi Arabia.

Background: Since the beginning of COVID-19 pandemic, many associated factors have been investigated to clarify the susceptibility and severity among the affected individuals. Biological markers can play an important role in identification of individual susceptibility to such pandemic. Growing evidence suggest the influence of different blood group systems on susceptibility to COVID-19 virus, with a particular blood type conferring selection advantage. Objectives: The study aimed to determine the association of ABO, Rhesus (D) and P1 blood groups with COVID-19 susceptibility in Taif city, Western Saudi Arabia. Methods: ABO, D and P1 blood antigens were determined in 104 blood samples of COVID-19 patients versus 100 control samples using either automated immunohematology analyser or test tube method. Statistical differences between patients and control samples were calculated based on p-value where results of ≤ 0.05 were considered significant. Results: O+ve blood group constituted the predominant type among the studied samples. Determination of P1 antigen showed significant association where Anti-P1 was positive in 76.9% of patients compared to 61.0% of controls with a P value of 0.01 conferring the susceptibility of P1+ve patients to COVID-19. Conclusion: Although our study showed no significant association between ABO and D, and susceptibility to COVID-19, there was a significant association between P1+ve and COVID-19. P1+ve participants were 2.131 times more associated with the risk of COVID-19 infection than those with Anti P1-ve. Thus, P1 antigen can be used as a biological marker for identification of individuals susceptibility to COVID-19. It is strongly advised that such individuals should consider extra protective measures. Further studies on other contributing factors should also be considered for more scientific clarity.

Secondary prevention of rheumatic heart disease in Ethiopia: a multicenter study.

BACKGROUND: Ethiopia has a high acute rheumatic fever (ARF) and rheumatic heart disease (RHD) prevalence, and to our knowledge, there are no data on the status of secondary prevention in children with RHD. This study describes the status of secondary RHD prevention. METHODS: A multicenter, prospective study was performed on children aged 5-17 years with RHD in Ethiopia. Good adherence was defined as at least 80% completion of benzathine penicillin (BPG) or oral Amoxicillin within the previous year. The primary outcome measure was adherence to prophylaxis, expressed as a proportion. Socio-demographics, severity of RHD, and ARF recurrence were evaluated. RESULTS: A total of 337 children with a mean age of 12.9 ± 2.6 years were included. The majority (73%) had severe aortic/mitral disease. Participants were on BPG (80%) or Amoxicillin (20%) prophylaxis. Female sex (P = 0.04) use of BPG (0.03) and shorter mean duration of prophylaxis in months (48.5 ± 31.5 vs. 60.7 ± 33, respectively, P < 0.008) predicted good adherence. Running out of medications (35%), interrupted follow-up (27%), and the COVID-19 pandemic (26%) were the most common reasons for missing prophylaxis. Recurrence of ARF was higher in participants on Amoxicillin compared with BPG (40% vs. 16%, P < 0.001) and in those with poor adherence compared with good adherence (36.8% vs. 17.9%, respectively, P = 0.005). Type and duration of prophylaxis (OR 0.5, CI = 0.24, 0.9, P = 0.02; OR = 1.1, CI = 1.1, 1.2, P = 0.04, respectively), and sex (OR = 1.9, CI = 1.1, 3.4, P = 0.03) were independent predictors of poor adherence. CONCLUSION: Poor adherence is prevalent in Ethiopian children living with RHD. Amoxicillin is a suboptimal option for prophylaxis as its use is associated with lower adherence and a higher rate of ARF recurrence.

An observational multi-centric COVID-19 sequelae study among health care workers.

Background: India has seen more than 43 million confirmed cases of COVID-19 as of April 2022, with a recovery rate of 98.8%, resulting in a large section of the population including the healthcare workers (HCWs), susceptible to develop post COVID sequelae. This study was carried out to assess the nature and prevalence of medical sequelae following COVID-19 infection, and risk factors, if any. Methods: This was an observational, multicenter cross-sectional study conducted at eight tertiary care centers. The consenting participants were HCWs between 12 and 52 weeks post discharge after COVID-19 infection. Data on demographics, medical history, clinical features of COVID-19 and various symptoms of COVID sequelae was collected through specific questionnaire. Finding: Mean age of the 679 eligible participants was 31.49 ± 9.54 years. The overall prevalence of COVID sequelae was 30.34%, with fatigue (11.5%) being the most common followed by insomnia (8.5%), difficulty in breathing during activity (6%) and pain in joints (5%). The odds of having any sequelae were significantly higher among participants who had moderate to severe COVID-19 (OR 6.51; 95% CI 3.46-12.23) and lower among males (OR 0.55; 95% CI 0.39-0.76). Besides these, other predictors for having sequelae were age (≥45 years), presence of any comorbidity (especially hypertension and asthma), category of HCW (non-doctors vs doctors) and hospitalisation due to COVID-19. Interpretation: Approximately one-third of the participants experienced COVID sequelae. Severity of COVID illness, female gender, advanced age, co-morbidity were significant risk factors for COVID sequelae. Funding: This work is a part of Indian Council for Medical Research (ICMR)- Rational Use of Medicines network. No additional financial support was received from ICMR to carry out the work, for study materials, medical writing, and APC.

Correlation of SARS-CoV-2 infection severity with ABO blood groups and RhD antigen: a case-control study.

OBJECTIVE: The role of ABO types and RhD antigen in coronavirus disease 2019 (COVID-19) severity has been investigated in several recent studies. Thus, the objective of this study was to identify the relationship of ABO and RhD types with symptomatic COVID-19 disease and determine the groups associated with an increased risk of hospitalization. METHODS: This observational case-control study was performed in 530 Iraqi-Kurdish patients with COVID-19. Among them, 184 were severe cases that required hospitalization, while 346 were mild to moderate cases that were treated at home. ABO and RhD antigen groups were compared between cases and 1698 control records from 1 year before the pandemic. The diagnosis of COVID-19 was based on real-time polymerase chain reaction tests and high-resolution chest computed tomography scans with the typical clinical presentation. RESULTS: There were no significant differences in ABO and RhD antigen distributions between the COVID-19 cases and non-COVID controls. No ABO group was associated with the risk of hospitalization as a marker of the severity of infection. CONCLUSIONS: There was no significant association between symptomatic COVID-19 disease and any ABO group or RhD antigen type. No impact of ABO groups on hospitalization was documented.

ABO and RhD blood group are not associated with mortality and morbidity in critically ill patients; a multicentre observational study of 29 512 patients.

BACKGROUND: The ABO and RhD blood group represent antigens on the surface of erythrocytes. The ABO blood group antigens are also present on multiple other cells. Interestingly, previous studies have demonstrated associations between the blood group and many types of disease. The present study aimed to identifying associations between the ABO blood group, the RhD blood group, and morbidity and mortality in a mixed cohort and in six pre-defined subgroups of critically ill patients. METHODS: Adult patients admitted to any of the five intensive care units (ICUs) in the Scania Region, Sweden, between February 2007 and April 2021 were eligible for inclusion. The outcomes were mortality analysed at 28- and 90-days as well as at the end of observation and morbidity measured using days alive and free of (DAF) invasive ventilation (DAF ventilation) and DAF circulatory support, including vasopressors or inotropes (DAF circulation), maximum Sequential Organ Failure Assessment score (SOFAmax) the first 28 days after admission and length of stay. All outcomes were analysed in separate multivariable regression models adjusted for age and sex. In addition, in a sensitivity analysis, five subgroups of patients with the main diagnoses sepsis, septic shock, acute respiratory distress syndrome, cardiac arrest and trauma were analysed using the same separate multivariable regression models. RESULTS: In total, 29,512 unique patients were included in the analyses. There were no significant differences for any of the outcomes between non-O blood groups and blood group O, or between RhD blood groups. In the sensitivity analysis of subgroups, there were no differences in mortality between non-O blood groups and blood group O or between the RhD blood groups. AB was the most common blood group in the COVID-19 cohort. CONCLUSIONS: The ABO and RhD blood group do not influence mortality or morbidity in a general critically ill patient population.

The COVID-19 Pandemic Surge and Impact on Rheumatic Valvular Heart Disease Patient Care.

The COVID-19 crisis has surged worldwide, putting immense stress on the health care services, leading to institutions deferring elective procedures and struggling to triage the emergency care of cardiac patients. This has affected the management of the rheumatic valvular heart disease patients especially, in developing countries, potentially placing these patients at enormous risk for complications like congestive cardiac failure, stroke and death. This article explores the COVID-19 pandemic and its impact on rheumatic valvular heart disease patient care. We try to provide a framework that addresses the procedural considerations of interventions like percutaneous transluminal mitral commissurotomy (PTMC), mitral and aortic valve surgeries. This article also highlights the implications for the outpatient valve clinic, and safety issues of the patient and health care workers during this ongoing pandemic.

Emphasizing the link between blood types in multi-ethnic disparities and COVID-19 infection in Makkah, Saudi Arabia.

OBJECTIVES: To analyze the impact and distribution of blood groups in different ethnicities and the extent of susceptibility to infection with COVID-19 in Makkah, Saudi Arabia. METHODS: A retrospective study was performed on 4,609 COVID-19 patients from five ethnic groups to assess the impact and distribution of different blood types and susceptibility to COVID-19 infection. The study was carried out between November 2020 and June 2021 in the College of Medicine, Umm Al-Qura University in collaboration with the General Directorate of Health Affairs, Makkah, Saudi Arabia. RESULTS: Blood group (A, B, and O) distributions in 2,617 COVID-19 patients with local control populations was done. Our study found that in both Saudi and non-Saudi populations, blood groups O and A were associated with higher infection rates, whereas blood group AB was associated with lower infection rates (p=0.0001). COVID-19 seems to be associated with blood groups A, B, and AB (RR=3.23, 95% CI=2.702-3.821, p=0.0001). COVID-19 risk was lower in people with O blood group (RR=0.783, 95% CI=0.733-0.836, p=0.0001). South Asians had higher odds of COVID-19 infection when compared to Saudi cases and other ethnic groups (OR=1.12, 95 % CI: 1.074-1.24, p=0.04). CONCLUSION: We emphasize that COVID-19 infection is not proportional among ethnically related blood groups. Notably, RhD-negative protect against COVID-19, whereas A and O blood types are more susceptible. Thus, when assessing COVID-19 prognosis and vaccination priority, blood groups A and O are critical.

The impact of ABO blood groups on clinical outcomes and susceptibility to COVID-19: A retrospective study in an unselected population.

BACKGROUND: ABO blood groups have been linked to susceptibility to infection with certain microorganisms, including coronaviruses. We examined the relationship between blood group and clinical outcomes in individuals infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and compared their blood group distribution with the general population. METHODS: At the inception of the pandemic, all individuals testing positive for SARS-CoV-2 in Kuwait were admitted to one designated coronavirus disease 2019 (COVID-19) hospital and enrolled in a prospective registry. Patients admitted from February 24 to May 27, 2020, were stratified according to blood group. As a control, blood groups of 3,730,027 anonymized individuals representing almost Kuwait's entire population were obtained from a national database. RESULTS: Of 3305 SARS-CoV-2-positive patients, 37.1%, 25.5%, 28.9%, and 8.5% were groups O, A, B, and AB, respectively. Univariate analysis revealed no significant differences in severe clinical outcomes or death among the blood groups. However, multivariable analysis demonstrated that group A individuals had higher odds of developing pneumonia compared with non-group A (adjusted odds ratio 1.32, 95% confidence interval 1.02-1.72, p < .036). Compared with the general population, the COVID-19 cohort had a lower frequency of group O, equivalent frequency of A, and higher frequency of B and AB. No significant difference in the RhD group was found. CONCLUSION: This study supports potential involvement of the ABO blood group system in predisposing to infection with SARS-CoV-2 in an unselected population. Examination of the mechanistic link between blood group and COVID-19 and its implications on controlling the current pandemic is warranted.