Analysis of the 2007-2018 National Health Interview Survey (NHIS): Examining Neurological Complications among Children with Sickle Cell Disease in the United States.

This study compared neurological complications among a national sample of United States children with or without sickle cell disease (SCD) and evaluated health status, healthcare and special education utilization patterns, barriers to care, and association of SCD status and demographics/socioeconomic status (SES) on comorbidities and healthcare utilization. Data was acquired from the National Health Interview Survey (NHIS) Sample Child Core questionnaire 2007-2018 dataset that included 133,542 children. An affirmation from the guardian of the child determined the presence of SCD. Regression analysis was used to compare the associations between SCD and demographics/SES on neurological conditions at p < 0.05. Furthermore, adjusted odds ratios (AORs) were estimated for having various neurological conditions. Of the 133,481 children included in the NHIS, the mean age was 8.5 years (SD: 0.02) and 215 had SCD. Of the children with SCD, the sample composition included male (n = 110), and Black (n = 82%). The SCD sample had higher odds of having neuro-developmental conditions (p < 0.1). Families of Black children (55% weighted) reported household incomes < 100% of federal poverty level. Black children were more likely to experience longer wait times to see the doctor (AOR, 0.3; CI 0.1-1.1). Compared to children without SCD, those with SCD had a greater chance of seeing a medical specialist within 12 months (AOR 2.3; CI 1.5-3.7). This representative sample of US children with SCD shows higher odds of developing neurological complications, increased healthcare and special education services utilization, with Black children experiencing a disproportionate burden. This creates the urgency to address the health burden for children with SCD by implementing interventions in healthcare and increasing education assistance programs to combat neurocognitive impairments, especially among Black children.

Racial and ethnic differences in sickle cell disease within the United States: From demographics to outcomes.

INTRODUCTION: Sickle cell disease mainly affects African Americans, and studies on racial differences in sickle cell disease outcomes are scanty. This study examined racial and ethnic differences in sickle cell disease prevalence, comorbidities, and outcomes. METHODS: Using the National Inpatient Sample database from 2016 to 2018, we identified patients' records with a diagnosis of sickle cell disease using the International Classification of Diseases, Tenth Revision codes. The overall study population was further stratified by race into Blacks, Whites, and Hispanics. Using logistic regression, comorbidities and outcomes among sickle cell disease patients were compared between the three races/ethnicities. RESULTS: Of the 74 817 hospitalized for sickle cell disease, 69 889 (93.4%) were Blacks, 3603 (4.8%) were Hispanics, and 1325 (1.8%) were Whites. Compared to Whites, Blacks were more likely to have significantly higher odds of sickle cell crisis (odds ratio [OR]: 3.32; 95% confidence interval [CI]: 2.66-4.14) and blood transfusion (OR: 1.66; 95% CI: 1.37-2.02). There was no difference in mortality between Blacks and Whites. Compared to Hispanics, Blacks had significantly higher odds of sickle cell crisis (OR: 1.35; 95% CI: 1.19-1.53) and blindness (OR: 2.94; 95% CI: 1.22-7.11), lower odds of asplenia (OR: 0.57; 95% CI: 0.45-0.71) and gallstones (OR: 0.75; 95% CI: 0.58-0.95). However, Blacks had statistically significantly lower odds of mortality of 0.60 (95% CI: 0.38-0.93) than Hispanics. CONCLUSION: Prevalent sickle cell type, severity, complications, and comorbidities vary in different races. Physicians need to be aware of these differences to manage sickle cell patients efficiently. This study hopes to inform further research regarding the reasons for varying disease characteristics among racial groups and bridge a gap in tailored management protocols.

Screening for Cognitive Dysfunction Using the Rowland Universal Dementia Assessment Scale in Adults With Sickle Cell Disease.

Importance: Adults with sickle cell disease (SCD) disproportionally experience early cognitive decline; however, guidance on the optimal screening strategy for cognitive dysfunction is lacking, and several available tools are biased by language, educational level, socioeconomic status, and race/ethnicity. The Rowland Universal Dementia Assessment Scale (RUDAS) was specifically designed for cognitive screening in multicultural populations. Objective: To ascertain the prevalence of suspected dementia in adults with SCD using the RUDAS, and to identify whether age, sex, educational level, several biological variables, and SCD complications were associated with RUDAS scores. Design, Setting, and Participants: This multicenter, bilingual, cross-sectional study was conducted in 2 SCD comprehensive care centers in Canada (Centre Hospitalier de l'Université Montréal in Montréal and University Health Network in Toronto). Participants were adults aged 18 years or older and were enrolled in the study between July 1, 2018, and July 30, 2019. All outpatients were eligible and offered study participation, unless they had an acute medical condition that required inpatient care or they were unable to follow study instructions. Interventions: The RUDAS was administered by trained personnel in either French or English, according to the patient's language preference. A questionnaire on social determinants of health was also administered, and participants underwent screening for anxiety and depression. Main Outcomes and Measures: Proportion of participants with RUDAS scores that were suggestive of dementia and the RUDAS score. Any score lower than 23 points was suggestive of dementia, a score between 23 and 27 points indicated a possible association with mild neurocognitive disorder, and a score higher than 27 points was normal. Results: A total of 252 adult patients with SCD were included (136 women [54.0%]; mean [range] age, 34.8 [18-75] years). Overall, 29 patients (11.5%) had RUDAS scores that were suggestive of dementia, and this proportion increased with age (15 [8.7%] in the 18-39 years age group, 10 [14.5%] in the 40-59 years age group, and 4 [36.4%] in the ≥60 years age group). The RUDAS scores were not associated with sex, language, SCD genotype, and SCD complications. The highest level of education was significantly associated with the RUDAS score; however, the association was small (η2 = 0.02; 95% CI, 0.00-0.07; P = .02). In a multivariable analysis, lower glomerular filtration rate (r = 0.40; 95% CI, 0.29-0.50; P < .001) and increasing age (r = -0.37; 95% CI, -0.47 to -0.26; P < .001), but not SCD genotype or disease severity, were associated with lower RUDAS scores. Conclusions and Relevance: This study found that using the RUDAS revealed a high prevalence of suspected dementia in adult patients with SCD that was associated with worsening kidney function and age. Cognition should be screened in all adult patients with SCD, regardless of age, disease severity, and SCD genotype; further validation of the RUDAS is ongoing.

Reflections of Healthcare Experiences of African Americans With Sickle Cell Disease or Cancer: A Qualitative Study.

BACKGROUND: The experiences of African American adult patients before, during, and after acute care utilization are not well characterized for individuals with sickle cell disease (SCD) or cancer. OBJECTIVE: To describe the experiences of African Americans with SCD or cancer before, during, and after hospitalization for pain control. METHODS: We conducted a qualitative study among African American participants with SCD (n = 15; 11 male; mean age, 32.7 ± 10.9 years; mean pain intensity, 7.8 ± 2.6) or cancer (n = 15; 7 male; mean age, 53.7 ± 15.2 years; mean pain intensity, 4.9 ± 3.7). Participants completed demographic questions and pain intensity using PAINReportIt and responded to a 7-item open-ended interview, which was recorded and transcribed verbatim. We used content analysis to identify themes in the participants' responses. RESULTS: Themes identified included reason for admission, hospital experiences, and discharge expectations. Pain was the primary reason for admission for participants with SCD (n = 15) and for most participants with cancer (n = 10). Participants of both groups indicated that they experienced delayed treatment and a lack of communication. Participants with SCD also reported accusations of drug-seeking behavior, perceived mistreatment, and feeling of not being heard or believed. Participants from both groups verbalized concerns about well-being after discharge and hopeful expectations. CONCLUSIONS: Race-concordant participants with SCD but not with cancer communicated perceived bias from healthcare providers. IMPLICATIONS FOR PRACTICE: Practice change interventions are needed to improve patient-provider interactions, reduce implicit bias, and increase mutual trust, as well as facilitate more effective pain control, especially for those who with SCD.

Relationship of Thrombospondin 1 to von Willebrand Factor and ADAMTS-13 in Sickle Cell Disease Patients of Arab Ethnicity.

BACKGROUND: Thrombospondin 1 (TSP-1) is a multifunctional glycoprotein secreted by platelets. In sickle cell disease (SCD), TSP-1 promotes red cell adhesion to the endothelium by binding to von Willebrand factor (vWF) and inhibiting its degradation by the protease ADAMTS-13. We investigated a possible correlation between TSP-1, vWF and ADAMTS-13 in adult and pediatric SCD patients. METHODS: Using commercially available ELISA kits, TSP-1, vWF and ADAMTS-13 levels were measured in 59 SCD patients (20 children and 39 adults) and compared with 59 age- and sex-matched controls. Associations between TSP-1 and parameters of interest were analyzed using Pearson's correlation coefficient. RESULTS: Although TSP-1 levels were higher in adult and pediatric SCD patients than in controls, the increase was not statistically significant (p > 0.05). We found a significant positive correlation between TSP-1 and platelet count in both adult (r = 0.402, p = 0.01) and pediatric (r = 0.589, p = 0.01) patients, which is expected due to increased platelet activation in SCD. There was a positive correlation between TSP-1 and vWF in normal adults (r = 0.305, p = 0.049) and children (r = 0.633, p = 0.005) but not in patients (p > 0.05). A significant negative correlation between TSP-1 and ADAMTS-13 activity (r = -0.41, p = 0.01) was found in adult patients. Also, a significant negative correlation between TSP-1 and ADAMTS-13/vWF antigen ratio in both normal controls (r = -0.595, p = 0.009) and patients (r = -0.493, p = 0.032) is reported for the pediatric group. CONCLUSIONS: Our findings confirm the inhibitory effects of TSP-1 on ADAMTS-13 activity in adult SCD patients. The negative correlation reported between TSP-1 and ADAMTS-13/vWF antigen ratio in pediatric subjects suggests a possible protective mechanism in younger individuals, although this is not related to the presence of SCD. This work emphasizes the impact of age on interpreting results related to the regulation of vWF expression and interaction with TSP-1 and ADAMTS-13 in SCD.

The Genetic and Clinical Significance of Fetal Hemoglobin Expression in Sickle Cell Disease.

Sickle cell disease (SCD) is phenotypically heterogeneous. One major genetic modifying factor is the patient's fetal hemoglobin (HbF) level. The latter is determined by the patient's ß-globin gene cluster haplotype and cis- and trans-acting single nucleotide polymorphisms (SNPs) at other distant quantitative trait loci (QTL). The Arab/India haplotype is associated with persistently high HbF levels and also a relatively mild phenotype. This haplotype carries the Xmn1 (C/T) SNP, rs7482144, in the HBG2 locus. The major identified trans-acting QTL contain SNPs residing in the BCL11A on chromosome 2 and the HMIP locus on chromosome 6. These collectively account for 15-30% of HbF expression in different world populations and in patients with SCD or ß-thalassemia. Patients with SCD in Kuwait and Eastern Saudi Arabia uniformly carry the Arab/India haplotype, but despite this, the HbF and clinical phenotypes show considerable heterogeneity. Pain episodes and avascular necrosis of the femoral head are particularly common, but severe bacterial infections, stroke, priapism, and leg ulcers are uncommon. Moreover, the HbF modifiers appear to be different; the reported BCL11A and HMIP SNPs appear to play insignificant roles. There are probably novel modifiers to be discovered in this population. This review examines the common clinical phenotypes in Kuwaiti patients with elevated HbF and the available information on HbF modifiers. The response of the patients to hydroxyurea is discussed. The presentation of patients with other sickle compound heterozygotes (Sßthal and HbSD), vis-à-vis their HbF levels, is also addressed critically.

An Analysis of Racial and Ethnic Backgrounds Within the CASiRe International Cohort of Sickle Cell Disease Patients: Implications for Disease Phenotype and Clinical Research.

Millions are affected by sickle cell disease (SCD) worldwide with the greatest burden in sub-Saharan Africa. While its origin lies historically within the malaria belt, ongoing changes in migration patterns have shifted the burden of disease resulting in a global public health concern. We created the Consortium for the Advancement of Sickle Cell Research (CASiRe) to understand the different phenotypes of SCD across 4 countries (USA, UK, Italy, and Ghana). Here, we report the multi-generational ethnic and racial background of 877 SCD patients recruited in Ghana (n = 365, 41.6%), the USA (n = 254, 29%), Italy (n = 81, 9.2%), and the UK (n = 177, 20.2%). West Africa (including Benin Gulf) (N = 556, 63.4%) was the most common geographic region of origin, followed by North America (N = 184, 21%), Caribbean (N = 51, 5.8%), Europe (N = 27, 3.1%), Central Africa (N = 24, 2.7%), and West Africa (excluding Benin Gulf) (N = 21, 2.4%). SCD patients in Europe were primarily West African (73%), European (10%), Caribbean (8%), and Central African (8%). In the USA, patients were largely African American (71%), Caribbean (13%), or West African (10%). Most subjects identified themselves as Black or African American; the European cohort had the largest group of Caucasian SCD patients (8%), including 21% of the Italian patients. This is the first report of a comprehensive analysis of ethnicity within an international, transcontinental group of SCD patients. The diverse ethnic backgrounds observed in our cohort raises the possibility that genetic and environmental heterogeneity within each SCD population subgroup can affect the clinical phenotype and research outcomes.

Diversity of variant alleles encoding Kidd, Duffy, and Kell antigens in individuals with sickle cell disease using whole genome sequencing data from the NHLBI TOPMed Program.

BACKGROUND: Genetic variants in the SLC14A1, ACKR1, and KEL genes, which encode Kidd, Duffy, and Kell red blood cell antigens, respectively, may result in weakened expression of antigens or a null phenotype. These variants are of particular interest to individuals with sickle cell disease (SCD), who frequently undergo chronic transfusion therapy with antigen-matched units. The goal was to describe the diversity and the frequency of variants in SLC14A1, ACKR1, and KEL genes among individuals with SCD using whole genome sequencing (WGS) data. STUDY DESIGN AND METHODS: Two large SCD cohorts were studied: the Recipient Epidemiology and Donor Evaluation Study III (REDS-III) (n = 2634) and the Outcome Modifying Gene in SCD (OMG) (n = 640). Most of the studied individuals were of mixed origin. WGS was performed as part of the National Heart, Lung, and Blood Institute's Trans-Omics for Precision Medicine (TOPMed) program. RESULTS: In SLC14A1, variants included four encoding a weak Jka phenotype and five null alleles (JKnull ). JKA*01N.09 was the most common JKnull . One possible JKnull mutation was novel: c.812G>T. In ACKR1, identified variants included two that predicted Fyx (FY*X) and one corresponding to the c.-67T>C GATA mutation. The c.-67T>C mutation was associated with FY*A (FY*01N.01) in four participants. FY*X was identified in 49 individuals. In KEL, identified variants included three null alleles (KEL*02N.17, KEL*02N.26, and KEL*02N.04) and one allele predicting Kmod phenotype, all in heterozygosity. CONCLUSIONS: We described the diversity and distribution of SLC14A1, ACKR1, and KEL variants in two large SCD cohorts, comprising mostly individuals of mixed ancestry. This information may be useful for planning the transfusion support of patients with SCD.

Some Lives Matter: The Dirty Little Secret of the U.S. Health Care System.

Our health care system in the United States reflects the inequities that are part of the larger society, which is why our system for financing access to needed and effective health care is so complicated and unfair.

Association between BCL11A, HSB1L-MYB, and XmnI γG-158 (C/T) gene polymorphism and hemoglobin F level in Egyptian sickle cell disease patients.

Sickle cell disease (SCD) is a monogenic disease characterized by multisystem morbidity and highly variable clinical course. Inter-individual variability in hemoglobin F (HbF) levels is one of the main modifiers that account for the clinical heterogeneity in SCD. HbF levels are affected by, among other factors, single nucleotide polymorphisms (SNPs) at the BCL11A gene and the HBS1L-MYB intergenic region and Xmn1 gene. Our aim was to investigate HbF-enhancer haplotypes at these loci to obtain a first overview of the genetic situation of SCD patients in Egypt and its impact on the severity of the disease. The study included 100 SCD patients and 100 matched controls. Genotyping of BCL11A (rs1886868 C/T), HBS1L-MYB (rs9389268 A/G) and Xmn1 γG158 (rs7842144 C/T) SNPs showed no statistically significant difference between SCD patients and controls except for the hetero-mutant genotypes of BCL11A which was significantly higher in SCD patients compared with controls. Baseline HbF levels were significantly higher in those with co-inheritance of polymorphic genotypes of BCL11A + HSB1L-MYB and BCL11A + Xmn1. Steady-state HbF levels, used as an indicator of disease severity, were significantly higher in SCD-Sß patients having the polymorphic genotypes of HSB1L-MYB. Fold change of HbF in both patient groups did not differ between those harboring the wild and the polymorphic genotypes of the studied SNPs. In conclusion, BCL11A, HSB1L, and Xmn1 genetic polymorphisms had no positive impact on baseline HbF levels solely but had if coexisted. Discovery of the molecular mechanisms controlling HbF production could provide a more effective strategy for HbF induction.

Coagulation Status and Venous Thromboembolism Risk in African Americans: A Potential Risk Factor in COVID-19.

Severe acute respiratory syndrome coronavirus 2 infection (COVID-19) is known to induce severe inflammation and activation of the coagulation system, resulting in a prothrombotic state. Although inflammatory conditions and organ-specific diseases have been shown to be strong determinants of morbidity and mortality in patients with COVID-19, it is unclear whether preexisting differences in coagulation impact the severity of COVID-19. African Americans have higher rates of COVID-19 infection and disease-related morbidity and mortality. Moreover, African Americans are known to be at a higher risk for thrombotic events due to both biological and socioeconomic factors. In this review, we explore whether differences in baseline coagulation status and medical management of coagulation play an important role in COVID-19 disease severity and contribute to racial disparity trends within COVID-19.

Pulmonary disease burden in Hispanic and non-Hispanic children with sickle cell disease.

RATIONALE: Pulmonary complications are the leading cause of morbidity and mortality in sickle cell disease (SCD) patients. Research in SCD has predominantly been conducted on African-Americans, and the disease burden of SCD in other races and ethnicities, including Hispanic patients, is not well characterized. OBJECTIVE: To compare pulmonary disease burden between Hispanic and non-Hispanic ethnic groups among children with SCD. METHODS: In a retrospective chart review on 566 SCD patients followed at the Children's Hospital at Montefiore, NY, we compared the pulmonary disease burden and disease management in Hispanic patients to their non-Hispanic counterparts. We also compared the contribution of demographic and clinical variables to acute chest syndrome (ACS), vaso-occlusive crisis (VOC), and hospitalizations for SCD related complications between the two ethnic groups. RESULTS: Hispanic patients had a greater proportion of ACS, and had lower forced expiratory volume (FEV1), forced vital capacity, and vital capacity, compared to non-Hispanics. Hispanic patients were more likely to be evaluated in pulmonary clinic and to be on inhaled corticosteroids, short-acting ß agonizts, and leukotriene receptor antagonists. In addition, Hispanic children were more likely to be on hydroxyurea, and receive exchange transfusions. However, the association of asthma with the proportion of ACS did not differ between Hispanics and non-Hispanics. CONCLUSION: Hispanic children with SCD had differences in their pulmonary function profile and received more pulmonary evaluations than non-Hispanic children.

Quality of Life of Latino and Non-Latino Youth With Sickle Cell Disease as Reported by Parents and Youth.

INTRODUCTION: Approximately 10% to 15% of people affected by sickle cell disease (SCD) in the United States are Latino, many of whom are primary Spanish speakers. A key tool for self-reported outcome measures, the Pediatric QOL Inventory (PedsQL) SCD module, was not available in Spanish. Here, we assess the linguistic validity of a Spanish translation and compare perception of disease-specific and generic quality of life (QOL) in a sample of Latino and non-Latino children with SCD and their parents. METHOD: Following forward and backward translation, Spanish-speaking child-parent dyads linguistically validated the translated instruments. Disease-specific and generic QOL perception of 28 child-parent dyads who participated in a clinical feasibility trial, HABIT (Hydroxyurea Adherence for Personal Best in Sickle Cell Disease), were compared by ethnicity. Data were analyzed by descriptive statistics, Mann-Whitney U test, absolute score differences, and minimal clinically important differences (MCID). RESULTS: The translated questionnaire required no further language changes. QOL scores were higher for Latino children and parents compared with non-Latinos, with score differences exceeding MCIDs for total scores and the majority of subscale scores. CONCLUSION: Spanish language PedsQL SCD instruments allow measurement of QOL in Spanish-speaking Latino children with SCD and their parents. Score differences for Latinos mostly exceeded MCIDs, suggesting that these differences are clinically meaningful. Confirmation of these findings is warranted.

Ocular Manifestations of Sickle Cell Disease: Signs, Symptoms and Complications.

BACKGROUND: Sickle cell disease is an inherited hematological disorder that can affect any organ in the body including the eyes (1-6). Previous studies on ocular manifestations of sickle cell disease generally included samples of less than 100 patients. In this study, we aim to assess the frequency of different ocular signs, symptoms and complications among sickle cell disease patients. METHODS: This study was conducted using data from the Cooperative Study of Sickle Cell Disease (CSSCD). Patients with major sickle cell hemoglobinopathies (SS, SC, S ß-thal) were eligible for enrollment. Patients from all age groups were included. Patients underwent detailed ophthalmological examination under standardized conditions. RESULTS: A total of 1904 patients were included in this study, with a mean age of 27.67 (±11.72) years. 1,802 (96.4%) patients had BCVA of more than 20/40 in the better-seeing eye. On slit lamp examination, the presence of vascular loops and segment, representing a positive conjunctival sign, was the most common reported abnormal finding (54.1%). The most common complication was peripheral retinal artery occlusion detected in225 patients (20.3%) bilaterally and 77 patients (6.9%) unilaterally. CONCLUSION: In this study that included one of the largest samples ever studied to assess ocular complications of sickle cell disease, we identified the frequency and percentages of different ocular signs, symptoms and complications in different age groups.

Sensitivities to Thermal and Mechanical Stimuli: Adults With Sickle Cell Disease Compared to Healthy, Pain-Free African American Controls.

Evidence supports, but is inconclusive that sensitization contributes to chronic pain in some adults with sickle cell disease (SCD). We determined the prevalence of pain sensitization among adults with SCD pain compared with pain-free healthy adults. In a cross sectional, single session study of 186 African American outpatients with SCD pain (age 18-74 years, 59% female) and 124 healthy age, gender, and race matched control subjects (age 18-69 years, 49% female), we compared responses to standard thermal (Medoc TSA II) and mechanical stimuli (von Frey filaments). Although we observed no significant differences in thermal thresholds between controls and patients, patients with SCD had lower pain thresholds to mechanical stimuli and reported higher pain intensity scores to all thermal and mechanical stimuli at a non-painful body site. Compared with controls, about twice as many patients with SCD showed sensitization: 12% versus 23% at the anterior forearm site (P = .02), and 16% versus 32% across 3 tested sites (P = .004). Among patients with SCD, 18% exhibited some element of central sensitization. Findings indicate that persistent allodynia and hyperalgesia can be part of the SCD pain experience and should be considered when selecting therapies for SCD pain. PERSPECTIVE: Compared with matched healthy controls, quantitative sensory testing in adults with pain and sickle cell disease (SCD) demonstrates higher prevalence of sensitization, including central sensitization. The findings of allodynia and hyperalgesia may indicate neuropathic pain and could contribute to a paradigm shift in assessment and treatment of SCD pain.

Comparative study of hypercoagulability change in steady state and during vaso-occlusive crisis among Sudanese patients living with sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) is an inherited blood disorder that affects red blood cells. (SCD) is characterized by recurrent vaso-occlusive crisis (VOC). MATERIAL AND METHODS: This was a descriptive cross sectional study conducted through the period from July 2015 to July 2017 in which a total of seventy two blood specimens were collected in 'EDTA' and citrated vacutainers from Sudanese patients with SCD attending "Fath Elrhman Albasheer" Centre. Both sexes' with different ages were included. Among these samples 49 (68.1%) were in steady state while the remained 23 (31.9%) were in VOC. All samples were tested for coagulation profile. RESULT: There was increase in fibrinogen and D-dimer levels in most patients 67% and 71%, respectively. Significant increase in D-dimers was observed in patients with (VOC) compared with steady state (P. value = 0.006). Protein S was significantly increased in males in comparison with females P. value = 0.017. The results of prothrombin time (PT), international normalized ratio (INR) and thrombin time (TT) were within normal range. CONCLUSION: Significant increase in levels of D-dimer during VOC indicating abnormal coagulation and fibrinolysis activation. Reduced levels of natural anticoagulants proteins C and S can be consider as predictive markers indicate hepatic dysfunction in patients with SCD.

Reducing Health Care Disparities in Sickle Cell Disease: A Review.

Sickle cell disease (SCD) is an inherited blood disorder most common among African American and Hispanic American persons. The disease can cause substantial, long-term, and costly health problems, including infections, stroke, and kidney failure, many of which can reduce life expectancy. Disparities in receiving health care among African Americans and other racial/ethnic minority groups in the United States are well known and directly related to poor outcomes associated with SCD. As an orphan disease-one that affects <200 000 persons nationwide-SCD does not receive the research funding and pharmaceutical investment directed to other orphan diseases. For example, cystic fibrosis affects fewer than half the number of persons but receives 3.5 times the funding from the National Institutes of Health and 440 times the funding from national foundations. In this review, we discuss the health inequities affecting persons with SCD, describe programs intended to improve their care, and identify actions that could be taken to further reduce these inequities, improve care, control treatment costs, and ease the burden of disease.

Genetic modulators of fetal hemoglobin expression and ischemic stroke occurrence in African descendant children with sickle cell anemia.

Sickle cell anemia (SCA) is an autosomal recessive monogenic disease with significant clinical variability. Cerebrovascular disease, particularly ischemic stroke, is one of the most severe complications of SCA in children. This study aimed to investigate the influence of genetic variants on the levels of fetal hemoglobin (Hb F) and biochemical parameters related with chronic hemolysis, as well as on ischemic stroke risk, in ninety-one unrelated SCA patients, children of sub-Saharan progenitors. Our results show that a higher Hb F level has an inverse relationship with the occurrence of stroke, since the group of patients who suffered stroke presents a significantly lower mean Hb F level (5.34 ± 4.57% versus 9.36 ± 6.48%; p = 0.024). Furthermore, the co-inheritance of alpha-thalassemia improves the chronic hemolytic pattern, evidenced by a decreased reticulocyte count (8.61 ± 3.58% versus 12.85 ± 4.71%; p < 0.001). In addition, our findings have confirmed the importance of HBG2 and BCL11A loci in the regulation of Hb F expression in sub-Saharan African SCA patients, as rs7482144_A, rs11886868_C, and rs4671393_A alleles are significantly associated with a considerable increase in Hb F levels (p = 0.019, p = 0.026, and p = 0.028, respectively). Concerning KLF1, twelve different variants were identified, two of them novel. Seventy-three patients (80.2%) presented at least one variant in this gene. However, no correlation was observed between the presence of these variants and Hb F level, severity of hemolysis, or stroke occurrence, which is consistent with their in silico-predicted minor functional consequences. Thus, we conclude that the prevalence of functional KLF1 variants in a sub-Saharan African background does not seem to be relevant to SCA clinical modulation.

Implication of HMOX1 and CCR5 genotypes on clinical phenotype of Egyptian patients with sickle cell anemia.

Sickle cell disease (SCD) is a relatively common inherited hemolytic anemia among individuals of African descent. Genetic factors might clarify clinical diversity of the disease and variations in treatment response. Some researchers investigated heme oxygenase-1 (HMOX1) or chemokine receptor 5 (CCR5Δ32) genotypes among SCD patients and their correlation with fetal hemoglobin (HbF) and disease severity. However, there are no such records among Arab nations. We aimed to estimate the prevalence of the HMOX1-413 A>T (rs2071746) and CCR5Δ32 (rs333) polymorphisms, and to assess their effect on SCD phenotype and HbF level among Egyptian patients. Polymerase chain reaction assay was used to determine these polymorphisms among 100 SCD patients and 100 healthy controls. Though not statistically significant, the frequency of individual carrying HMOX-1 polymorphic AT and TT genotypes in both patient and control groups was 92% and 85% respectively. Regarding CCR5Δ32 polymorphisms, all SCD patients harbored the wild genotype (100%), while the heteromutant genotype was encountered in 2% of our controls. Patients harboring mutant HMOX-1 had a less frequent vaso-occlusive crisis (VOC)/lifetime, less VOC in the last year, less incidence of stroke, less frequency of hospitalization, and responded more frequently to hydroxyurea with statistically significant differences (p = 0.028, 0.007, 0.046, 0.007, and 0.011 respectively). No significant associations with HbF level or other hematologic parameters were encountered among our cohort. Our study results suggest a protective effect of mutant HMOX-1 genotypes in ameliorating the phenotypic severity of the disease. HMOX1-413 A>T (rs2071746) polymorphisms might prove to be a prognostic marker among Egyptian SCD, but not CCR5Δ32 (rs333) polymorphisms.