Sickle cell disease incidence among newborns in New York State by maternal race/ethnicity and nativity

Infrequent Resolution of Vaso-Occlusive Crises in Routine Clinical Care Among Patients Mimicking the Exa-Cel Trial Population: A Cohort Study of Medicaid Enrollees

The CRISPR-based gene editing therapy exagamglogene autotemcel (exa-cel) recently received FDA approval for patients with severe sickle cell disease (SCD). The approval was based on a phase III trial (CLIMB SCD 121), which showed 97% efficacy of this treatment in eliminating vaso occlusive crises (VOCs) for 12 consecutive months. To help contextualize results from this trial, we aimed to investigate the proportion of patients with severe SCD who remain VOC-free for a 1-year period in routine clinical care. Using Medicaid claims data (2000-2018), we identified a cohort of patients, 12-35 years old with severe SCD, defined by ≥ 2 VOCs per year for 2 consecutive years, who met other exa-cel trial inclusion criteria to mimic a trial-like population. A VOC was identified using ICD diagnosis codes during hospitalization and ER visits. The primary outcome was the proportion of patients with no VOCs during a 1-year follow-up. A total of 7,425 patients with severe SCD [mean (SD) age: 20.5 (6.0) years, 54.6% females, 84% African Americans], had a mean of 5.2 VOCs, 5.1 ER visits and 3.5 hospitalizations per year during the baseline period. The proportion of patients with no VOCs during the 1-year follow-up was 7.7% (95% confidence interval: 7.1%-8.3%). In conclusion, less than one in 12 patients with severe SCD achieved VOC-free status within 1 year in routine clinical care. These findings suggest that the high efficacy observed for exa-cel in the trial, if replicated in routine clinical care, could translate into a significant public health impact.

Sickle Cell Disease and Lead Poisoning in New York City, 2005-2019

OBJECTIVES

Previous analyses of New York City (NYC) health department's lead registry indicated that, among children with lead poisoning, an increased prevalence of sickle cell disease (SCD) exists. However, SCD is not considered a risk factor for lead poisoning. We assessed the association between SCD and childhood lead poisoning to determine if specific lead poisoning prevention efforts are needed for children with SCD.

METHODS

We analyzed NYC's lead registry data for children with venous blood lead levels (BLLs) ≥15 mcg/dL during 2005 to 2019. t tests and χ2 tests were performed to compare demographic characteristics, BLLs, and lead exposure risks in non-Hispanic Black children with and without SCD. A t test was used to compare observed SCD prevalence among Black children with BLLs ≥15 mcg/dL with an estimated 0.43% SCD prevalence among Black NYC children.

RESULTS

Among 1728 Black children with BLLs ≥15 mcg/dL identified, 37 (2.14%) had SCD. When comparing children with and without SCD, both mean age at peak BLL (62.8 versus 42.7 months; P = .003) and peak BLL (42.59 versus 23.06 mcg/dL; P = .008) were higher for children with SCD. Among risk factors for lead exposure, children with SCD had higher prevalence of pica. Observed SCD prevalence was 1.71% higher than estimated SCD prevalence among Black NYC children (P < .001).

CONCLUSIONS

We found a potential association between SCD and childhood lead poisoning. Pica emerged as a potentially important risk factor. Our findings might have implications for lead poisoning prevention guidelines for children with SCD.

Sleep experiences of parents of children 18 years or younger with sickle cell disease during the COVID-19 pandemic: a qualitative study

STUDY OBJECTIVES

The coronavirus disease pandemic has highlighted disparities in health care. Parents assist in sickle cell disease management in children. Understanding sleep in parents of children who are diagnosed with sickle cell disease is an important facet of disease management. Our objectives were to identify sleep characteristics of parents of children with sickle cell disease age 18 years or younger during the coronavirus disease pandemic, to investigate measures used by parents to achieve restful sleep, and to discuss how sleep may be improved in parents of children diagnosed with sickle cell disease.

METHODS

This study conducted 14 face-to-face semistructured interviews with parents of children diagnosed with sickle cell disease. A majority of the interviews (93%) were conducted at a hematology clinic. Qualitative thematic analysis was used to analyze data.

RESULTS

All parents reported that their child experienced pain because of sickle cell disease. Most parents (86.7%) reported that their child was diagnosed with sickle cell anemia. Four themes were identified: difficulty obtaining restful sleep during their child's sickle cell crisis, sleep during the coronavirus disease pandemic, factors affecting sleep, and effects of sleep disturbance and deprivation on parental performance.

CONCLUSIONS

This research has highlighted some of the difficulties experienced by parents of children who are diagnosed with sickle cell disease and allows for additional insight into the sleep experiences of parents as they attempt to manage their child's disease.

CITATION

Osborne JC, Odlum M, Sedrak A. Sleep experiences of parents of children 18 years or younger with sickle cell disease during the COVID-19 pandemic: a qualitative study. J Clin Sleep Med. 2024;20(5):777-782.

Adhesion molecules and cerebral microvascular hemodynamic abnormalities in sickle cell disease

Cerebrovascular abnormalities are a common feature of sickle cell disease that may be associated with risk of vaso-occlusive pain crises, microinfarcts, and cognitive impairment. An activated endothelium and adhesion factors, VCAM-1 and P-selectin, are implicated in sickle cell vasculopathy, including abnormal hemodynamics and leukocyte adherence. This study examined the association between cerebral expression of these adhesion factors and cortical microvascular blood flow dynamics by using in-vivo two-photon microscopy. We also examined the impact of blood transfusion treatment on these markers of vasculopathy. Results showed that sickle cell mice had significantly higher maximum red blood cell (RBC) velocity (6.80 ± 0.25 mm/sec, p ≤ 0.01 vs. 5.35 ± 0.35 mm/sec) and more frequent blood flow reversals (18.04 ± 0.95 /min, p ≤ 0.01 vs. 13.59 ± 1.40 /min) in the cortical microvasculature compared to controls. In addition, sickle cell mice had a 2.6-fold (RFU/mm2) increase in expression of VCAM-1 and 17-fold (RFU/mm2) increase in expression of P-selectin compared to controls. This was accompanied by an increased frequency in leukocyte adherence (4.83 ± 0.57 /100 μm/min vs. 2.26 ± 0.37 /100 μm/min, p ≤ 0.001). We also found that microinfarcts identified in sickle cell mice were 50% larger than in controls. After blood transfusion, many of these parameters improved, as results demonstrated that sickle cell mice had a lower post-transfusion maximum RBC velocity (8.30 ± 0.98 mm/sec vs. 11.29 ± 0.95 mm/sec), lower frequency of blood flow reversals (12.80 ± 2.76 /min vs. 27.75 ± 2.09 /min), and fewer instances of leukocyte adherence compared to their pre-transfusion imaging time point (1.35 ± 0.32 /100 μm/min vs. 3.46 ± 0.58 /100 μm/min). Additionally, we found that blood transfusion was associated with lower expression of adhesion factors. Our results suggest that blood transfusion and adhesion factors, VCAM-1 and P-selectin, are potential therapeutic targets for addressing cerebrovascular pathology, such as vaso-occlusion, in sickle cell disease.

Sickle cell disease among Latinx in California

INTRODUCTION

After African Americans, Latinx are the second largest population affected by Sickle Cell Disease (SCD) in the U.S. However, research has largely ignored how this devastating rare blood disorder specifically affects Latinx nationwide.

METHODS

This study compared demographics, genotypes, primary insurance, and health care utilization among Latinx and non-Latinx Californians living with SCD, using data from the California SCD Data Collection Program (2016-2018) and newborn screening cases 2000-2017.

RESULTS

Stemming from 6,837 SCD patients, 501(7%) were Latinx. Latinx with SCD (Lx-SCD) were statistically significantly younger than non-Latinx (NLx-SCD) counterparts. Within both groups, females predominated, with 70% being insured by Medicaid. Mean Emergency Department encounters were statistically significantly lower among Lx-SCD adults.

DISCUSSION

Lx-SCD differ in age, genotype, and Emergency Department utilization, when compared to NLx-SCD counterparts in California. Latinx are now the largest racial and/or ethnic group in the US, and their presence in SCD population is expected to grow. Therefore, their specific demographic, genotypic, and health care utilization characteristics merit attention to inform policies and programs that will improve their health.

Maternal hereditary hemolytic anemia and birth defects in the National Birth Defects Prevention Study

OBJECTIVES

Hereditary hemolytic anemia (HHA) results from genetic mutations that cause red blood cell abnormalities. Little research exists on the relationship between HHA and birth defects. Using data from the National Birth Defects Prevention Study (NBDPS), we described characteristics of HHA-exposed women and estimated associations between HHA during pregnancy and specific birth defects.

METHODS

The NBDPS was a population-based, case-control study of major birth defects and included pregnancies with estimated delivery dates from October 1997 through December 2011. Participants were ascertained from hospital discharge lists or birth defect registries at 10 sites. Trained interviewers collected information about pregnancy exposures via telephone questionnaire. We described characteristics among HHA-exposed women and calculated crude odds ratios and exact 95% confidence intervals for defects with ≥3 exposed cases.

RESULTS

Among 31 HHA-exposed women (28 cases/3 controls), 13 (42%) reported sickle cell anemia, 17 (55%) reported thalassemia, and one (3%) reported hereditary spherocytosis. The average age at delivery for HHA-exposed case women was 27.3 years (range: 17-38). The majority (82%) of HHA-exposed case women reported additional conditions during pregnancy, including hypertension, genitourinary infections, and respiratory illnesses. Additionally, 93% of case women reported using medication during pregnancy. Among the 28 cases, 18 (64%) had isolated birth defects. The defects with ≥3 exposed cases were anencephaly, atrial septal defect, gastroschisis, and cleft palate. Except for anencephaly, the 95% confidence intervals for all estimates were close to or included the null.

CONCLUSION

This hypothesis-generating study adds to the sparse literature on the association between HHA and birth defects.

Food insecurity, housing instability, and dietary quality among children with sickle cell disease: Assessment from a single urban center

BACKGROUND

Food insecurity and housing instability, both social determinants of health (SDoH), disproportionately affect economically unstable, under-resourced US communities in which children with sickle cell disease (SCD) live. Association between these SDoH markers and dietary quality among children with SCD is unknown.

PROCEDURES

We assessed a cross-sectional sample of dyadic parent-child patients and young adult patients up to age 21 from one pediatric SCD center. Food insecurity, housing instability, and dietary quality were measured using validated US instruments and a food frequency questionnaire. Better dietary quality was defined using US dietary guidelines. Multivariate regression assessed for associations among dietary quality and food insecurity with or without (±) housing instability and housing instability alone.

RESULTS

Of 100 enrolled participants, 53% were Black and 43% Hispanic; mean age 10.6 ± 5.6 years. Overall, 70% reported less than or equal to one economic instability: 40% housing instability alone and 30% both food insecurity and housing instability. Eighty percent received more than or equal to one federal food assistance benefit. Compared to no economic instability, food insecurity ± housing instability was significantly associated with higher intake of higher dairy and pizza, while housing instability alone was significantly associated with higher dairy intake. Food insecurity ± housing instability was significantly associated with lower intake of whole grains compared to housing instability alone.

CONCLUSIONS

Our sample reported high frequencies of both food insecurity and housing instability; having more than or equal to one SDoH was associated with elements of poorer diet quality. Screening families of children with SCD for food insecurity and housing instability may identify those with potential nutrition-related social needs.

Maternal mortality among women with sickle cell disease in Jamaica over two decades (1998-2017)

BACKGROUND

Sickle cell disease (SCD) affects 2.8% of Jamaican antenatal women. Between 1998-2007 their maternal mortality ratio was 7-11 times higher than women without these disorders. We aim to determine if outcomes improved between 2008 and 17 amid declining fertility and changes in referral obstetric care.

METHODS

Maternal deaths in Jamaica's maternal mortality surveillance database (assembled since 1998) with SCD reported as underlying or associated cause of death were compared to those without known SCD, over two decades from 1998 to 2017. Social, demographic and health service variables were analysed using SPSS and EpiInfo Open.

FINDINGS

Over the two decades from 1998 to 2017, 806 (74%) of the 1082 pregnancy-associated deaths documented by the Jamaican Ministry of Health and Wellness were maternal deaths. The maternal mortality ratio (MMR) did not statistically change over the two periods for women with (p = 0.502) and without SCD (p = 0.629). The MMR among women with and without SCD in 2008-17 was 378.1 (n = 41) and 89.2/100,000 live births (n = 336) respectively, an odds ratio of 4.24 (95% CI: 3.07-5.87). When deaths due to their blood disorders were excluded, risk remained elevated at 2.17 (95% CI: 1.36-3.32). There was an upward trend in direct deaths over the two decades (p [trend]=0.051).

INTERPRETATION

MMRs were unchanged over two decades for Jamaicans with SCD. The high contribution to maternal mortality by women with SCD may explain some of the persistently higher mortality experience of women in the African diaspora. Multi-disciplinary evidence-based strategies need to be developed and tested which improve survival for women with SCD who want to have children.

FUNDING

No external funding was provided.

Colocating Wound Care for Patients with Sickle Cell Ulcers in a Hematology Clinic

OBJECTIVE

Leg ulcers affect 15% of people with sickle cell disease. However, wound centers typically treat few people with this condition, which makes it difficult to concentrate clinical expertise or support the scientific study of this orphan disease. This article describes an initiative to increase engagement in care through a partnership between wound healing and hematology leadership that led to colocating wound services within a sickle cell clinic.

METHODS

Via a retrospective chart review, the authors collected records of all adult patients with sickle cell disease who received wound care in the last decade, including 7 years of wound center data and 3 years of data from the colocated services. Patient and visit characteristics were analyzed using descriptive analytics.

RESULTS

The general wound center had previously treated 35 patients with sickle cell ulcers over 7 years. In contrast, colocated services engaged 56 patients within 3 years, including 20 who transferred care and 36 new patients. The majority of patients at the colocated site were women, unlike at the wound center (58% vs 47%, P = .07). Results indicated that 36% of patients healed initial wounds, and 45% had new wound occurrences.

CONCLUSIONS

Colocation successfully increases the number of patients with sickle cell ulcers who will engage in wound care at a single site, laying the foundation for clinical studies to improve the evidence base for this difficult-to-treat condition.

Developing an emergency department order set to treat acute pain in sickle cell disease

STUDY OBJECTIVE

Patients with sickle cell disease (SCD) have many emergency department visits because of painful vaso-occlusive episodes (VOE). Guidelines recommend treatment within 30 minutes of triage, but this is rarely achieved in clinical practice. Our goal was to develop an order set that is being implemented in the ED to facilitate and standardize emergency care for SCD patients in acute pain from VOEs presenting to the emergency department (ED) in New York City (NYC).

METHODS

Using a RAND/University of California, Los Angeles modified Delphi panel, we convened a multidisciplinary panel and reviewed evidence on how to best manage SCD pain in the ED. Panelists collaboratively developed then rated 202 items that could be included in an ED order set.

RESULTS

A consensus order set, a practical how-to guide for managing SCD pain in the ED, was developed based on items that received high median ratings.

CONCLUSIONS

The management of acute pain experienced during VOEs is critical to patients with SCD; ED order sets, such as this one, can help standardize pain management, including at triage, evaluation, discharge, and follow-up care. After implementation in NYC EDs, studies to examine changes in quality care metrics (eg, wait times, readmissions) are planned.

Opioid Use in Adults With Sickle Cell Disease Hospitalized During Vaso-Occlusive Crisis: A Systematic Review

Background

While pain is the hallmark of sickle cell disease (SCD), healthcare personnel are often ill-equipped to adequately treat patients who present in vaso-occlusive crisis (VOC). Although symptom severity varies from individual to individual, SCD is characterized by intervallic pain as a result of oxygen deprivation in tissues and organs. Regardless of pain severity, SCD patients are often viewed as drug seekers by healthcare personnel who have concerns regarding patients’ dependence on opioids which may lead to addiction. The objective was to assess the types and amount of opioids used to treat VOC in comparison to Centers for Disease Control opioid prescription guidelines.

Methods

Literature search was conducted using CINAHL, PubMed, the Cochrane Library, Web of Science and hand search. Data were analyzed from 1999 to 2018. Randomized trials, observational, and case studies involved hospitalized adults with SCD who were prescribed opioids to treat VOC. Quality assessment was conducted using Downs and Black checklist. Meta-analysis was not conducted.

Results

Five studies were conducted in the USA, Arabia and the Netherlands, and the USA and Canada were included. Participants were treated with either morphine or morphine milligram equivalent (MME). No study used the same method of opioid administration.

Conclusions

Patients with SCD who are hospitalized secondary to VOC mostly received opioids for pain well within the Centers for Disease Control and Prevention prescription guidelines. No uniform method exists. Additional research is warranted.

Acute Appendicitis in Pediatric Patients With Sickle Cell Disease: Lower Incidence, More Imaging, and More False-Positives

OBJECTIVE

Patients with sickle cell disease (SCD) experience recurrent pain crises, which may mimic appendicitis. A prior study found a significantly lower rate of appendicitis in patients with SCD compared with national averages. We investigate the incidence of appendicitis and number of imaging studies for appendicitis in pediatric patients with SCD.

METHODS

Using a retrospective study design from a single institution, SCD and control cohorts were created. Inclusion criteria included age 0 to 21years and at least one follow-up appointment within 24 months. Length of observation was calculated from initial presentation to either inpatient admission for appendicitis or last clinic visit. Analysis of an SCD subgroup and a control subset (n = 1,596) was used to compare the number of imaging studies. Incidence rates of appendicitis and number of appendicitis studies were determined. Z-tests, binomial enumeration exact tests, and Fischer's exact tests were used.

RESULTS

The SCD cohort included 1,064 patients between January 1, 2001, to December 31, 2014, and the control cohort included 115,109 patients without SCD between January 1, 2011, and December 31, 2011. Incidence rate of appendicitis per 10,000 patient-years was significantly lower in the SCD group compared with controls (2.9 cases versus 10.7 cases per 10,000 patient-years; P = .044). Additionally, the SCD group received significantly more ultrasounds (148 versus 60 per 10,000 patient-years; P< .0001) and CTs (94 versus 27 per 10,000 patient-years; P< .0001) for appendicitis, which remained significant when controlling for race. Patients with SCD also received more false-positive scans.

DISCUSSION

Patients with SCD had a significantly lower incidence of appendicitis than controls, yet had a higher number of imaging tests performed for appendicitis. Appendicitis should be viewed as a less common cause of acute abdominal pain in SCD. This consideration should help guide imaging strategy.

Effect of immigration on mortality trends in sickle cell patients

BACKGROUND

Sickle cell patient population in the U.S. continues to increase due a combination of birth of sickle cell disease infants, extension of lifespan of existing patients and also possibly, a contributing immigration component. These factors and most importantly the latter, might be altering national estimates by both underestimating the number of affected individuals as well as underestimating the impact of public health strategies given the estimates for which there were conceived.

METHODS

National sickle cell disease estimates as per Centers for Disease Control (CDC) and immigrant population trends obtained from the U.S. Census Bureau from years 2010-2017 were examined. Immigrant groups from geographical regions highly prevalent for sickle cell disease were evaluated throughout this period of time.

RESULTS

From years 2010 to 2017 Western Africa (Nigeria, Ghana, Cape Verde, Liberia, Sierra Leona), showed a population increase of 45.2%, 44.15%, 24%, 19.0% and 16.3% respectively. Eastern Africa (Ethiopia, Kenya and Eritrea) had a population increase of 55.7%, 46.8% and 65% respectively. Caribbean island (Dominican Republic, Haiti and Jamaica) showed an increase of 31.8%, 18.6% and 46.8% respectively. Extrapolation of the prevalence in these populations shows that the sickle cell disease prevalence is likely higher than what is reported in US.

CONCLUSIONS

The complexities of reaching an estimated number may be more challenging in an ever-changing and growing population. More so considering the different situations behind the immigration of each group and the migratory status which might be inducing an underestimation of the sickle cell population in the U.S. This study attempts to shed light on factors that may be skewing previous statistical estimates. Examining the migratory aspects inducing possible statistical bias may contribute to further address this disease encompassing this population's growth rate into prospective public health strategies to a more comprehensive approach to the disease.

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 β 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.

Improving an Administrative Case Definition for Longitudinal Surveillance of Sickle Cell Disease

Objective:

Several states are building infrastructure and data collection methods for longitudinal, population-based surveillance systems for selected hemoglobinopathies. The objective of our study was to improve an administrative case definition for sickle cell disease (SCD) to aid in longitudinal surveillance.

Methods:

We collected data from 3 administrative data sets (2004-2008) on 1998 patients aged 0-21 in Georgia who had ≥1 encounter in which an SCD International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code was recorded, and we compared these data with data from a laboratory and medical record review. We assessed performance (sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) of case definitions that differed by number and type of SCD-coded encounters; addition of SCD-associated treatments, procedures, and complications; and length of surveillance (1 vs 5 years). We identified correct diagnoses for patients who were incorrectly coded as having SCD.

Results:

The SCD case definition of ≥3 SCD-coded encounters in 5 years simplified and substantially improved the sensitivity (96.0% vs 85.8%) and NPV (68.2% vs 38.2%) of the original administrative case definition developed for 5-year, state-based surveillance (≥2 encounters in 5 years and ≥1 encounter for an SCD-related treatment, procedure, or complication), while maintaining a similar PPV (97.4% vs 97.4%) and specificity (76.5% vs 79.0%).

Conclusions:

This study supports an administrative case definition that specifies ≥3 ICD-9-CM–coded encounters to identify SCD with a high degree of accuracy in pediatric patients. This case definition can be used to help establish longitudinal SCD surveillance systems.

Sickle cell disease

Sickle cell disease (SCD) is a group of inherited disorders caused by mutations in HBB, which encodes haemoglobin subunit β. The incidence is estimated to be between 300,000 and 400,000 neonates globally each year, the majority in sub-Saharan Africa. Haemoglobin molecules that include mutant sickle β-globin subunits can polymerize; erythrocytes that contain mostly haemoglobin polymers assume a sickled form and are prone to haemolysis. Other pathophysiological mechanisms that contribute to the SCD phenotype are vaso-occlusion and activation of the immune system. SCD is characterized by a remarkable phenotypic complexity. Common acute complications are acute pain events, acute chest syndrome and stroke; chronic complications (including chronic kidney disease) can damage all organs. Hydroxycarbamide, blood transfusions and haematopoietic stem cell transplantation can reduce the severity of the disease. Early diagnosis is crucial to improve survival, and universal newborn screening programmes have been implemented in some countries but are challenging in low-income, high-burden settings.

An analysis of inpatient pediatric sickle cell disease: Incidence, costs, and outcomes

OBJECTIVE

To identify characteristics of pediatric sickle cell disease (SCD) hospitalizations and to examine admission demographics and medical expenditures.

METHODS

Admissions with SCD were identified from the 2009 and 2012 releases of the Healthcare and Cost Utilization Project's Kids Inpatient Database. Disease-specific secondary diagnoses including acute chest syndrome (ACS), vaso-occlusive pain crisis (VOC), splenic sequestration, and stroke/transient ischemic attack were analyzed for patient and hospital demographics. Analytical endpoints included total healthcare expenditures and mortality.

RESULTS

We reviewed 75,234 inpatient hospitalizations with a diagnosis of SCD. Over $900,000,000 was spent annually in associated healthcare expenditure. The median length of hospitalization stay (LOS) for all admissions was 3 days (interquartile range [IQR] 2-5 days). VOC was the most frequent secondary diagnosis, recording 48,698 total hospitalizations and a median LOS of 3 days (IQR 2-6 days). Of the 8,490 hospitalizations with ACS, the infant population had a significantly higher mortality rate compared to other age groups (2% vs. 0.3%, P < 0.001). Cerebral vascular accidents incurred the second highest median hospitalization cost ($18,956), behind ACS ($22,631). A high proportion of Caucasian patients died during hospitalization for VOC (0.4% vs. 0.1%, P = 0.014) and ACS (4% vs. 0.2%, P < 0.001) when compared to non-Caucasians.

CONCLUSION

Inpatient hospitalizations for secondary manifestations of pediatric SCD were associated with significant healthcare expenditures. Patients with an increased statistical risk for death during hospitalization included Caucasians with SCD complications of ACS and VOC, and patients <1-year-old with ACS. Further research is needed to substantiate the associated clinical significance of these findings.

Prevalence of Sickle Cell Disease among Newborns in St Vincent and the Grenadines: A Retrospective Study

Objective

In the United States of America (USA), sickle cell disease (SCD) occurs in 1:375 African-American births. However, published data from the Caribbean have revealed higher numbers for some Caribbean islands. St Vincent and the Grenadines (SVG) is a multi-island nation in the Caribbean, and there are currently no data on the incidence or prevalence of the disease in this population. The objective of this study was to obtain birth prevalence estimates for SCD in SVG.

Methods

A retrospective review of haemoglobin electrophoresis test results at the laboratory of the main hospital in SVG for the period of October 1, 2005 to December 31, 2013 was done. Test results and demographic data were extracted to determine the estimated birth prevalence of SCD.

Results

The estimated birth prevalence of SCD was found to be 1:172 live births, and 86% of the patients were diagnosed after one year of age.

Conclusion

The birth prevalence of SCD in SVG was higher than those in the USA, but was similar to the numbers in other Caribbean populations.

Newborn Screening for Sickle Cell Disease in St. Vincent and the Grenadines: Results of a Pilot Newborn Screening Program

Objective: To pilot a newborn screening program for sickle cell disease (SCD) in St. Vincent and the Grenadines using a novel partnership method to determine the feasibility of a universal newborn screening program in this country. Methods: A prospective study of mothers and their newborns was conducted between January 1, 2015, and November 1, 2015, at the country's main hospital. Mothers of infants born at this hospital were offered screening for SCD for their infants. If accepted, the newborn's heel-stick blood specimen was obtained and mailed to the South Carolina Department of Health and Environmental Control Newborn Screening Laboratory for testing. Samples were analyzed for variant hemoglobins using standard laboratory techniques and results were communicated to local physicians. Feasibility was determined by a benchmark of having >50% of SCD patients receive the diagnosis and initiate disease-specific care by 3 months of age. Descriptive statistics were completed using SAS 9.4. Results: There were 1147 newborn infants screened for SCD. Of these, 123 (10.7%) had results indicative of sickle trait and 3 patients (0.3%) were diagnosed with SCD: 1 with HbSS and 2 with HbSC. All 3 patients with SCD received treatment before 3 months of age. Conclusions: A newborn screening program is feasible in this population when partnered with an established newborn screening laboratory.

Different pain responses to chronic and acute pain in various ethnic/racial groups

AIM

Our goal in this study was to review the similarities and differences among ethnic groups and their respective responses to acute and chronic clinically related and experimentally induced pain.

METHOD

In this review, the PUBMED and Google-Scholar databases were searched to analyze articles that have assessed the variations in both acute and chronic pain responses among different ethnic/racial groups.

RESULTS

According to the results from 42 reviewed articles, significant differences exist among ethnic-racial groups for pain prevalence as well as responses to acute and chronic pain. Compared with Caucasians, other ethnic groups are more susceptible to acute pain responses to nociceptive stimulation and to the development of long-term chronic pain.

CONCLUSION

These differences need to be addressed and assessed more extensively in the future in order to minimize the pain management disparities among various ethnic-racial groups and also to improve the relationship between pain management providers and their patients.

Hydroxyurea Use in Young Children With Sickle Cell Anemia in New York State

INTRODUCTION

This study examined hydroxyurea usage in young children with sickle cell anemia within New York State (NYS). The cohort was 273 children with sickle cell anemia born in NYS in 2006-2009 and enrolled essentially continuously in Medicaid for the first 4 years of life.

METHODS

Medicaid data were used to examine hydroxyurea usage in this group by age at first prescription fill, persistence, region, treatment institution, and year. Log-binomial regression models were used to estimate the likelihood of receiving hydroxyurea treatment. Data from birth through 2014 for all members of the study group were assembled and analyzed in 2015.

RESULTS

About 25% of the cohort had at least one filled hydroxyurea prescription by their fifth birthday, and nearly 40% by the end of the study period. The mean proportion of days covered for the first year of therapy was 56.3%. Adherence was also assessed by calculating medication possession ratios for individual treatment periods. Slightly more than one third of treated children showed 80% coverage by these measures. There was a consistent, but not statistically significant, trend toward younger age at first fill. Significant regional and treatment center differences in initiation of hydroxyurea use, but not in persistence after initiation, were noted among NYS centers.

CONCLUSIONS

Subsequent to clinical studies demonstrating safety, current NYS-wide use of hydroxyurea in young children with sickle cell anemia appears to be widespread and increasing. However, practice differences between treatment centers and inadequate adherence may limit the full disease-modifying effects of hydroxyurea.

Quality Indicator Development for Positive Screen Follow-up for Sickle Cell Disease and Trait

Extensive variation exists in the follow-up of positive screens for sickle cell disease. Limited quality indicators exist to measure if the public health goals of screening-early initiation of treatment and enrollment to care-are being achieved. This manuscript focuses on the development of quality indicators related to the follow-up care for individuals identified with sickle cell disease and trait through screening processes. The authors used a modified Delphi method to develop the indicators. The process included a comprehensive literature review with rating of the evidence followed by ratings of draft indicators by an expert panel held in September 2012. The expert panel was nominated by leaders of various professional societies, the Health Resources and Services Administration, and the National Heart, Lung, and Blood Institute and met face to face to discuss and rate each indicator. The panel recommended nine quality indicators focused on key aspects of follow-up care for individuals with positive screens for sickle cell disease and trait. Public health programs and healthcare institutions can use these indicators to assess the quality of follow-up care and provide a basis for improvement efforts to ensure appropriate family education, early initiation of treatment, and appropriate referral to care for individuals identified with sickle cell disease and trait.

Sickle cell in Latin America and the United States [corrected]

Latin Americans are an underappreciated population affected by sickle cell disease (SCD). Sickle trait and SCD exist throughout Latin America and U.S. Latino communities. We describe the epidemiology and genetic heterogeneity of SCD among Latin Americans, and fetal hemoglobin expression. National population-based newborn screening for SCD is limited to Brazil, Costa Rica, and the U.S. Available and extrapolated data suggest that over 6,000 annual births and 100,000-150,000 Latin Americans are affected by SCD. This comprehensive review highlights the substantial numbers and population distribution of SCD and sickle trait in Latin America, and where national newborn screening programs for SCD exist.

Population based surveillance in sickle cell disease: methods, findings and implications from the California registry and surveillance system in hemoglobinopathies project (RuSH)

BACKGROUND

There are no population-based surveillance systems to determine prevalence, impact or outcomes in sickle cell disease (SCD). Estimates of the SCD population in California range broadly from 4,500 to 7,000, and little is known about their health status, health care utilization or health outcomes. A surveillance strategy was implemented using diverse data sources to develop a multi-dimensional, state-based surveillance system for SCD that includes adults and children and describes utilization, treatment and outcomes.

PROCEDURE

Data from California newborn screening, inpatient and emergency room records, Medi-Cal/Medicaid claims and two SCD special care centers were collected for 2004-2008. A multi-step, iterative linkage process was used to link and de-duplicate these data sources, and case definitions were used to categorize cases.

RESULTS

After linking and de-duplicating, there were 1,975 confirmed cases of SCD, 3,159 probable cases as well as 8,024 possible cases. Among individual data sources, newborn screening and data from clinics contributed the greatest number of unique cases to the total. Select analyses of utilization and treatments for the population are described.

CONCLUSIONS

Using linked existing data sources, an estimate of the statewide count of the SCD population is possible. The approach can be used to create an in-depth health status profile of the affected population by aggregating utilization, treatment, and outcomes data including mortality and morbidity information. This effort sets the stage for development of an on-going, state-based surveillance system.

Meeting the emerging public health needs of persons with blood disorders

In its decades-long history, the Division of Blood Disorders (DBD) at CDC has evolved from a patient-focused, services-supporting entity at inception, to one of the world leaders in the practice of public health to improve the lives of people at risk for or affected by nonmalignant blood disorders. The DBD's earliest public health activities consisted of working with care providers in a network of hemophilia treatment centers to provide AIDS risk reduction services to people with hemophilia. Because this infectious disease threat has been reduced over time as a result of the development of safer treatment products, the DBD--under the auspices of congressional appropriations guidance--has expanded its core activities to encompass blood disorders other than hemophilia, including hemoglobinopathies such as thalassemia and sickle cell disease, and Diamond Blackfan anemia. Simultaneously, in transitioning to a greater public health role, the DBD has expanded its network of partners to new consumer and professional organizations, as well as state and other federal health agencies. The DBD has also developed and maintains many surveillance and registry activities beyond the Universal Data Collection system aimed at providing a better understanding of the health status, health needs, and health-related quality of life of people with nonmalignant blood disorders. The DBD has integrated applicable components of the Essential Services of Public Health successfully to promote and advance the agenda of blood disorders in public health.

Mortality of New York children with sickle cell disease identified through newborn screening

PURPOSE

Long-term follow-up of newborn screening for conditions such as sickle cell disease can be conducted using linkages to population-based data. We sought to estimate childhood sickle cell disease mortality and risk factors among a statewide birth cohort with sickle cell disease identified through newborn screening.

METHODS

Children with sickle cell disease identified by newborn screening and born to New York residents in 2000-2008 were matched to birth and death certificates. Mortality rates were calculated (using numbers of deaths and observed person-years at risk) and compared with mortality rates for all New York children by maternal race/ethnicity. Stratified analyses were conducted to examine associations between selected factors and mortality.

RESULTS

Among 1,911 infants with sickle cell disease matched to birth certificates, 21 deaths were identified. All-cause mortality following diagnosis was 3.8 per 1,000 person-years in the first 2 years of life and 1.0 per 1,000 person-years at ages 2-9 years. The mortality rate was significantly lower among children of foreign-born mothers and was significantly higher among preterm infants with low birth weight. The mortality rates were not significantly higher for infants after 28 days with sickle cell disease than for all New York births, but they were 2.7-8.4 times higher for children 1 through 9 years old with homozygous sickle cell disease than for those of all non-Hispanic black or Hispanic children born to New York residents.

CONCLUSION

Estimated mortality risk in children with homozygous sickle cell disease remains elevated even after adjustment for maternal race/ethnicity. These results provide evidence regarding the current burden of child mortality among children with sickle cell disease despite newborn screening.Genet Med 17 6, 452-459.

Personalized medicine, availability, and group disparity: an inquiry into how physicians perceive and rate the elements and barriers of personalized medicine

BACKGROUND

The success of personalized medicine depends on factors influencing the availability and implementation of its new tools to individualize clinical care. However, little is known about physicians' views of the availability of personalized medicine across racial/ethnic groups and the relationship between perceived availability and clinical implementation. This study examines physicians' perceptions of key elements/tools and potential barriers to personalized medicine in connection with their perceptions of the availability of the latter across subpopulations.

METHODS

Study subjects consisted of physicians recruited from Cincinnati Children's Hospital Medical Center and UC Health. An electronic survey conducted from September 2012 to November 2012 recruited 104 physicians. Wilcoxon rank sum analysis compared groups.

RESULTS

Physicians were divided about whether personalized medicine contributes to health equality, as 37.4% of them believe that personalized medicine is currently available only for some subpopulations. They also rated the importance of racial/ethnic background almost as high as the importance of genetic information in the delivery of personalized medicine. Actual elements of personalized medicine rated highest include family history, drug-drug interaction alerts in medical records, and biomarker measurements to guide therapy. Costs of gene-based therapies and genetic testing were rated the most significant barriers. The ratings of several elements and barriers were associated with perceived availability of personalized medicine across subpopulations.

CONCLUSION

While physicians hold differing views about the availability and implementation of personalized medicine, they likewise establish complex relationships between race/ethnicity and personalized medicine that may carry serious implications for its clinical success.

Racial and socioeconomic disparities in presentation and outcomes of well-differentiated thyroid cancer

CONTEXT

Racial/ethnic minorities suffer disproportionate morbidity and mortality from chronic diseases.

OBJECTIVE

Our objective was to assess racial and socioeconomic status (SES) disparities in well-differentiated thyroid cancer (WDTC) patients.

DESIGN AND PARTICIPANTS

We conducted a retrospective cohort study on 25 945 patients with WDTC (1999-2008) from the California Cancer Registry (57% white, 4% black, 24% Hispanic, and 15% Asian-Pacific Islander [API]).

MAIN OUTCOMES

We evaluated effect of race and SES variables on stage of cancer presentation and overall/disease-specific survival.

RESULTS

Significant differences in stage of presentation between all racial groups were found (P<.001), with minority groups presenting with a higher percentage of metastatic disease as compared with white patients (black, odds ratio [OR]=1.36 with confidence interval [CI] 1.01-1.84; Hispanic, OR=1.89 [CI, 1.62-2.21], API, OR=1.82 [CI, 1.54-2.15]). Hispanic (OR=1.59, [CI, 1.48-1.72]) and API (OR=1.32 [1.22-1.44]) patients also presented with higher odds of regional disease. Patients with the lowest SES presented with metastatic disease more often than those with the highest SES (OR=1.45 [CI, 1.16-1.82]). Those that were poor/uninsured and/or with Medicaid insurance had higher odds of presenting with metastatic disease as compared with those with private insurance (OR=2.41, [CI, 2.10-2.77]). Unadjusted overall survival rates were higher among API and Hispanic patients and lower among black patients (P<.001 vs white patients). Adjusted overall survival also showed a survival disadvantage for black patients (hazard ratio=1.4, [CI, 1.10-1.73]) and survival advantage for API patients (hazard ratio=0.83, [CI, 0.71-0.97]). In disease-specific survival analyses, when only those patients with metastatic disease were analyzed separately, black patients again had the lowest survival rates, and Hispanic/API patients had the highest survival rates (P<.04).

CONCLUSION

Black patients and those with low SES have worse outcomes for thyroid cancer. API and Hispanic patients may have a protective effect on survival despite presenting with more advanced disease.