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Browsing by Author "Gordeuk, Victor R."
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Item Biomarkers of Clinical Severity in Treated and Untreated Sickle Cell Disease: A Comparison by Genotypes of a Single Center Cohort and African Americans in the NHANES Study(Wiley, 2021) Njoku, Franklin; Zhang, Xu; Shah, Binal N.; Machado, Roberto F.; Han, Jin; Saraf, Santosh L.; Gordeuk, Victor R.; Medicine, School of MedicineHaemolysis and vaso-occlusion underlie multi-organ system complications in sickle cell disease (SCD). We assessed real-world biomarkers in University of Illinois adult SCD patients, categorised as severe (HbSS/Sβ0 -thalassaemia; n = 342) or mild (HbSC/Sβ+ -thalassaemia; n = 100) genotypes and stratified according to treatment. African-American controls from the National Health and Nutrition Examination Survey (NHANES) were matched with each genotype category. Most measures of haemolysis, anaemia, inflammation and function of kidneys, liver and lungs differed markedly in untreated severe genotype patients compared to NHANES controls. These same biomarkers were significantly closer to the NHANES control range in untreated mild versus severe genotype patients, but they were not improved in severe genotype patients receiving treatment with hydroxycarbamide or blood transfusions, except that haemoglobin and HbF were higher with hydroxycarbamide. Systolic blood pressures did not differ among the SCD and NHANES groups, but diastolic pressures were higher in mild genotype patients. Ferritin in severe genotype patients on chronic transfusions was 50-fold higher than NHANES controls. The cross-sectional real-world biomarkers of patients on hydroxycarbamide or transfusions were not markedly improved compared to untreated patients. This may be due partly to poor compliance or more severe disease. Our findings highlight the need for more effective treatments.Item The CYB5R3c.350C>G and G6PD A alleles modify severity of anemia in malaria and sickle cell disease(Wiley, 2020-11) Gordeuk, Victor R.; Shah, Binal N.; Zhang, Xu; Thuma, Philip E.; Zulu, Stenford; Moono, Rodgers; Reading, N. Scott; Song, Jihyun; Zhang, Yingze; Nouraie, Mehdi; Campbell, Andrew; Minniti, Caterina P.; Rana, Sohail R.; Darbari, Deepika S.; Kato, Gregory J.; Niu, Mei; Castro, Oswaldo L.; Machado, Roberto; Gladwin, Mark T.; Prchal, Josef T.; Medicine, School of MedicineGenetic modifiers of anemia in Plasmodium falciparum infection and sickle cell disease (SCD) are not fully known. Both conditions are associated with oxidative stress, hemolysis and anemia. The CYB5R3 gene encodes cytochrome b5 reductase 3, which converts methemoglobin to hemoglobin through oxidation of NADH. CYB5R3c.350C > G encoding CYB5R3T117S , the most frequent recognized African-specific polymorphism, does not have known functional significance, but its high allele frequency (23% in African Americans) suggests a selection advantage. Glucose-6-phosphate dehydrogenase (G6PD) is essential for protection from oxidants; its African-polymorphic X-linked A+ and A- alleles, and other variants with reduced activity, coincide with endemic malaria distribution, suggesting protection from lethal infection. We examined the association of CYB5R3c.350C > G with severe anemia (hemoglobin <5 g/dL) in the context of G6PD A+ and A- status among 165 Zambian children with malaria. CYB5R3c.350C > G offered protection against severe malarial anemia in children without G6PD deficiency (G6PD wild type or A+/A- heterozygotes) (odds ratio 0.29, P = .022) but not in G6PD A+ or A- hemizygotes/homozygotes. We also examined the relationship of CYB5R3c.350C > G with hemoglobin concentration among 267 children and 321 adults and adolescents with SCD in the US and UK and found higher hemoglobin in SCD patients without G6PD deficiency (β = 0.29, P = .022 children; β = 0.33, P = .004 adults). Functional studies in SCD erythrocytes revealed mildly lower activity of native CYB5R3T117S compared to wildtype CYB5R3 and higher NADH/NAD+ ratios. In conclusion, CYB5R3c.350C > G appears to ameliorate anemia severity in malaria and SCD patients without G6PD deficiency, possibly accounting for CYB5R3c.350C > G selection and its high prevalence.Item Exercise Induced Changes of Vital Signs in Adults with Sickle Cell Disease(Wiley, 2021) Johnson, Solomon; Gordeuk, Victor R.; Machado, Roberto; Gibbs, J. Simon R.; Hildesheim, Mariana; Little, Jane A.; Kato, Gregory J.; Gladwin, Mark T.; Nouraie, Mehdi; Medicine, School of MedicineThe six-minute walk test (6MWT) has been used in patients with sickle cell disease (SCD), in conjunction with tricuspid regurgitant velocity (TRV) and plasma N-terminal pro-brain natriuretic peptide (NT-pro BNP), to assess risk of having pulmonary hypertension. Exercise-induced vital sign changes (VSCs) are predictors of clinical outcomes in other diseases. In this study, we assess the predictors and prognostic value of 6MWT VSC in adult SCD patients. Data from a multinational study of SCD patients (Treatment of Pulmonary Hypertension with Sildenafil: walk-PHaSST) were used to calculate the 6MWT VSC. Predictors of VSC were identified by a multivariable analysis, and a survival analysis was conducted by the Cox proportional hazard method. An increase in heart rate was observed in 90% of the 630 SCD adults, 77% of patients had an increase in systolic blood pressure (SBP), and 50% of patients had a decrease in oxygen saturation. TRV (odds ratio [OR] = 1.82, p = .020), absolute reticulocyte count (OR = 1.03, p < .001), and hemoglobin (OR = 0.99, p = .035) predicted oxygen desaturation ≥ 3% during the 6MWT. In the adjusted analysis, SBP increase during the 6MWT was associated with improved survival (hazards ratio = 0.3, 95% confidence interval: 0.1-0.8). Increases in heart rate and blood pressure, as well as oxygen desaturation, are common in adults with SCD during the 6MWT. VSC is associated with markers of anemia and TRV and can be used for risk stratification. Any increase in SBP during the 6MWT was associated with improved survival and may be indicative of a patient's ability to increase stroke volume.Item Haptoglobin 1 allele predicts higher serum haptoglobin concentration and lower multiorgan failure risk in sickle cell disease(ASH Publications, 2022-12-22) Ruiz, Maria A.; Shah, Binal N.; Ren, Guohui; Hussain, Faiz; Njoku, Franklin; Machado, Roberto F.; Gordeuk, Victor R.; Saraf, Santosh L.; Medicine, School of MedicineHaptoglobin (HP) is an acute-phase protein and the main scavenger of cell-free hemoglobin. When HP is depleted, as observed in hemolytic conditions such as sickle cell disease (SCD), cell-free hemoglobin can lead to acute organ damage. The impact of the HP 1-1, 2-1, and 2-2 isoforms on HP and cell-free hemoglobin concentrations and SCD-related complications is unclear. In a longitudinal cohort of patients with SCD, the HP 1 allele was associated with higher HP and lower cell-free hemoglobin concentrations at a routine clinic visit as well as during hospitalization for a vaso-occlusive episode or acute chest syndrome. With a median follow-up of 6.8 years, acute chest syndrome occurred in 42% (n = 163) and multiorgan failure in 14% (n = 53) of 391 patients with SCD with a minimum follow-up of 6 months. The HP 1 allele was independently associated with lower risk of developing multiorgan failure during acute chest syndrome (additive model hazard ratio, 0.5; P < .001). Future studies assessing the regulation of HP concentrations and ability to bind cell-free hemoglobin according to the HP genotype may help to identify patients with SCD at high risk for multiorgan failure and to guide interventions, such as rapid initiation of exchange transfusion or HP replacement therapy.Item Hyperkalemia and Metabolic Acidosis Occur at a Higher eGFR in Sickle Cell Disease(Wolters Kluwer, 2022-02-03) Saraf, Santosh L.; Derebail, Vimal K.; Zhang, Xu; Machado, Roberto F.; Gordeuk, Victor R.; Lash, James P.; Little, Jane; Medicine, School of MedicineBackground: People with sickle cell disease (SCD) have an elevated estimated glomerular filtration rate (eGFR) compared with the general population, and this may alter the usual creatinine-based eGFR cutoffs for which physiologic evidence of kidney dysfunction is apparent. This study aimed to identify eGFR thresholds for hyperkalemia and metabolic acidosis in patients with SCD. Methods: This was a cross-sectional analysis of 733 patients with severe (hemoglobin SS or Sβ0-thalassemia) SCD genotype, 238 patients with moderate (hemoglobin SC or Sβ+-thalassemia) SCD genotype, and 1333 age- and sex-matched African Americans from the National Health and Nutrition Examination Survey (NHANES). The prevalence rates of hyperkalemia and metabolic acidosis were compared by eGFR category. Cutoffs for hyperkalemia and metabolic acidosis were determined using generalized additive models. Results: Hyperkalemia and metabolic acidosis were more common in those with severe SCD genotype (13% and 21%, respectively) compared with the NHANES (0.3% and 5%, respectively); the prevalence rates in the moderate SCD genotype were intermediate for hyperkalemia (3%) and metabolic acidosis (11%). The proportion of patients with hyperkalemia and metabolic acidosis progressively increased with lower eGFR category in both SCD genotype groups. The eGFR thresholds for hyperkalemia and metabolic acidosis were higher in the severe (85 and 91 ml/min per 1.73 m2, respectively) and moderate (52 and 102 ml/min per 1.73 m2, respectively) SCD genotypes compared with the NHANES (34 and 46 ml/min per 1.73 m2). Conclusions: We demonstrate that hyperkalemia and metabolic acidosis are more common and occur at higher eGFR values in patients with SCD compared with age- and sex-matched African Americans, including in eGFR ranges considered to be normal. Future studies using redefined creatinine-based eGFR thresholds for abnormal kidney function may identify high-risk patients for earlier intervention strategies and referral for specialized renal care in SCD.Item The impact of delayed treatment of uncomplicated P. falciparum malaria on progression to severe malaria: A systematic review and a pooled multicentre individual-patient meta-analysis(Public Library of Science, 2020-10-19) Mousa, Andria; Al-Taiar, Abdullah; Anstey, Nicholas M.; Badaut, Cyril; Barber, Bridget E.; Bassat, Quique; Challenger, Joseph D.; Cunnington, Aubrey J.; Datta, Dibyadyuti; Drakeley, Chris; Ghani, Azra C.; Gordeuk, Victor R.; Grigg, Matthew J.; Hugo, Pierre; John, Chandy C.; Mayor, Alfredo; Migot-Nabias, Florence; Opoka, Robert O.; Pasvol, Geoffrey; Rees, Claire; Reyburn, Hugh; Riley, Eleanor M.; Shah, Binal N.; Sitoe, Antonio; Sutherland, Colin J.; Thuma, Philip E.; Unger, Stefan A.; Viwami, Firmine; Walther, Michael; Whitty, Christopher J. M.; William, Timothy; Okell, Lucy C.; Pediatrics, School of MedicineBackground Delay in receiving treatment for uncomplicated malaria (UM) is often reported to increase the risk of developing severe malaria (SM), but access to treatment remains low in most high-burden areas. Understanding the contribution of treatment delay on progression to severe disease is critical to determine how quickly patients need to receive treatment and to quantify the impact of widely implemented treatment interventions, such as ‘test-and-treat’ policies administered by community health workers (CHWs). We conducted a pooled individual-participant meta-analysis to estimate the association between treatment delay and presenting with SM. Methods and findings A search using Ovid MEDLINE and Embase was initially conducted to identify studies on severe Plasmodium falciparum malaria that included information on treatment delay, such as fever duration (inception to 22nd September 2017). Studies identified included 5 case–control and 8 other observational clinical studies of SM and UM cases. Risk of bias was assessed using the Newcastle–Ottawa scale, and all studies were ranked as ‘Good’, scoring ≥7/10. Individual-patient data (IPD) were pooled from 13 studies of 3,989 (94.1% aged <15 years) SM patients and 5,780 (79.6% aged <15 years) UM cases in Benin, Malaysia, Mozambique, Tanzania, The Gambia, Uganda, Yemen, and Zambia. Definitions of SM were standardised across studies to compare treatment delay in patients with UM and different SM phenotypes using age-adjusted mixed-effects regression. The odds of any SM phenotype were significantly higher in children with longer delays between initial symptoms and arrival at the health facility (odds ratio [OR] = 1.33, 95% CI: 1.07–1.64 for a delay of >24 hours versus ≤24 hours; p = 0.009). Reported illness duration was a strong predictor of presenting with severe malarial anaemia (SMA) in children, with an OR of 2.79 (95% CI:1.92–4.06; p < 0.001) for a delay of 2–3 days and 5.46 (95% CI: 3.49–8.53; p < 0.001) for a delay of >7 days, compared with receiving treatment within 24 hours from symptom onset. We estimate that 42.8% of childhood SMA cases and 48.5% of adult SMA cases in the study areas would have been averted if all individuals were able to access treatment within the first day of symptom onset, if the association is fully causal. In studies specifically recording onset of nonsevere symptoms, long treatment delay was moderately associated with other SM phenotypes (OR [95% CI] >3 to ≤4 days versus ≤24 hours: cerebral malaria [CM] = 2.42 [1.24–4.72], p = 0.01; respiratory distress syndrome [RDS] = 4.09 [1.70–9.82], p = 0.002). In addition to unmeasured confounding, which is commonly present in observational studies, a key limitation is that many severe cases and deaths occur outside healthcare facilities in endemic countries, where the effect of delayed or no treatment is difficult to quantify. Conclusions Our results quantify the relationship between rapid access to treatment and reduced risk of severe disease, which was particularly strong for SMA. There was some evidence to suggest that progression to other severe phenotypes may also be prevented by prompt treatment, though the association was not as strong, which may be explained by potential selection bias, sample size issues, or a difference in underlying pathology. These findings may help assess the impact of interventions that improve access to treatment.Item RASA3 is a candidate gene in sickle cell disease-associated pulmonary hypertension and pulmonary arterial hypertension(Wiley, 2023-04-01) Prohaska, Clare C.; Zhang, Xu; Schwantes‐An, Tae‐Hwi L.; Stearman, Robert S.; Hooker, Stanley; Kittles, Rick A.; Aldred, Micheala A.; Lutz, Katie A.; Pauciulo, Michael W.; Nichols, William C.; Desai, Ankit A.; Gordeuk, Victor R.; Machado, Roberto F.; Medicine, School of MedicinePulmonary hypertension (PH) is associated with significant morbidity and mortality. RASA3 is a GTPase activating protein integral to angiogenesis and endothelial barrier function. In this study, we explore the association of RASA3 genetic variation with PH risk in patients with sickle cell disease (SCD)-associated PH and pulmonary arterial hypertension (PAH). Cis-expression quantitative trait loci (eQTL) were queried for RASA3 using whole genome genotype arrays and gene expression profiles derived from peripheral blood mononuclear cells (PBMC) of three SCD cohorts. Genome-wide single nucleotide polymorphisms (SNPs) near or in the RASA3 gene that may associate with lung RASA3 expression were identified, reduced to 9 tagging SNPs for RASA3 and associated with markers of PH. Associations between the top RASA3 SNP and PAH severity were corroborated using data from the PAH Biobank and analyzed based on European or African ancestry (EA, AA). We found that PBMC RASA3 expression was lower in patients with SCD-associated PH as defined by echocardiography and right heart catheterization and was associated with higher mortality. One eQTL for RASA3 (rs9525228) was identified, with the risk allele correlating with PH risk, higher tricuspid regurgitant jet velocity and higher pulmonary vascular resistance in patients with SCD-associated PH. rs9525228 associated with markers of precapillary PH and decreased survival in individuals of EA but not AA. In conclusion, RASA3 is a novel candidate gene in SCD-associated PH and PAH, with RASA3 expression appearing to be protective. Further studies are ongoing to delineate the role of RASA3 in PH.Item Whole Genome Sequencing Analysis of Body Mass Index Identifies Novel African Ancestry-Specific Risk Allele(medRxiv, 2023-08-22) Zhang, Xinruo; Brody, Jennifer A.; Graff, Mariaelisa; Highland, Heather M.; Chami, Nathalie; Xu, Hanfei; Wang, Zhe; Ferrier, Kendra; Chittoor, Geetha; Josyula, Navya S.; Li, Xihao; Li, Zilin; Allison, Matthew A.; Becker, Diane M.; Bielak, Lawrence F.; Bis, Joshua C.; Boorgula, Meher Preethi; Bowden, Donald W.; Broome, Jai G.; Buth, Erin J.; Carlson, Christopher S.; Chang, Kyong-Mi; Chavan, Sameer; Chiu, Yen-Feng; Chuang, Lee-Ming; Conomos, Matthew P.; DeMeo, Dawn L.; Du, Margaret; Duggirala, Ravindranath; Eng, Celeste; Fohner, Alison E.; Freedman, Barry I.; Garrett, Melanie E.; Guo, Xiuqing; Haiman, Chris; Heavner, Benjamin D.; Hidalgo, Bertha; Hixson, James E.; Ho, Yuk-Lam; Hobbs, Brian D.; Hu, Donglei; Hui, Qin; Hwu, Chii-Min; Jackson, Rebecca D.; Jain, Deepti; Kalyani, Rita R.; Kardia, Sharon L. R.; Kelly, Tanika N.; Lange, Ethan M.; LeNoir, Michael; Li, Changwei; Marchand, Loic Le; McDonald, Merry-Lynn N.; McHugh, Caitlin P.; Morrison, Alanna C.; Naseri, Take; NHLBI Trans-Omics for Precision Medicine (TOPMed) Consortium; O'Connell, Jeffrey; O'Donnell, Christopher J.; Palmer, Nicholette D.; Pankow, James S.; Perry, James A.; Peters, Ulrike; Preuss, Michael H.; Rao, D. C.; Regan, Elizabeth A.; Reupena, Sefuiva M.; Roden, Dan M.; Rodriguez-Santana, Jose; Sitlani, Colleen M.; Smith, Jennifer A.; Tiwari, Hemant K.; Vasan, Ramachandran S.; Wang, Zeyuan; Weeks, Daniel E.; Wessel, Jennifer; Wiggins, Kerri L.; Wilkens, Lynne R.; Wilson, Peter W. F.; Yanek, Lisa R.; Yoneda, Zachary T.; Zhao, Wei; Zöllner, Sebastian; Arnett, Donna K.; Ashley-Koch, Allison E.; Barnes, Kathleen C.; Blangero, John; Boerwinkle, Eric; Burchard, Esteban G.; Carson, April P.; Chasman, Daniel I.; Chen, Yii-Der Ida; Curran, Joanne E.; Fornage, Myriam; Gordeuk, Victor R.; He, Jiang; Heckbert, Susan R.; Hou, Lifang; Irvin, Marguerite R.; Kooperberg, Charles; Minster, Ryan L.; Mitchell, Braxton D.; Nouraie, Mehdi; Psaty, Bruce M.; Raffield, Laura M.; Reiner, Alexander P.; Rich, Stephen S.; Rotter, Jerome I.; Shoemaker, M. Benjamin; Smith, Nicholas L.; Taylor, Kent D.; Telen, Marilyn J.; Weiss, Scott T.; Zhang, Yingze; Heard-Costa, Nancy; Sun, Yan V.; Lin, Xihong; Cupples, L. Adrienne; Lange, Leslie A.; Liu, Ching-Ti; Loos, Ruth J. F.; North, Kari E.; Justice, Anne E.; Biostatistics and Health Data Science, School of MedicineObesity is a major public health crisis associated with high mortality rates. Previous genome-wide association studies (GWAS) investigating body mass index (BMI) have largely relied on imputed data from European individuals. This study leveraged whole-genome sequencing (WGS) data from 88,873 participants from the Trans-Omics for Precision Medicine (TOPMed) Program, of which 51% were of non-European population groups. We discovered 18 BMI-associated signals (P < 5 × 10−9). Notably, we identified and replicated a novel low frequency single nucleotide polymorphism (SNP) in MTMR3 that was common in individuals of African descent. Using a diverse study population, we further identified two novel secondary signals in known BMI loci and pinpointed two likely causal variants in the POC5 and DMD loci. Our work demonstrates the benefits of combining WGS and diverse cohorts in expanding current catalog of variants and genes confer risk for obesity, bringing us one step closer to personalized medicine.