An international learning collaborative phase 2 trial for haploidentical bone marrow transplant in sickle cell disease.

ABSTRACT: In the setting of a learning collaborative, we conducted an international multicenter phase 2 clinical trial testing the hypothesis that nonmyeloablative-related haploidentical bone marrow transplant (BMT) with thiotepa and posttransplant cyclophosphamide (PTCy) will result in 2-year event-free survival (no graft failure or death) of at least 80%. A total of 70 participants were evaluable based on the conditioning protocol. Graft failure occurred in 8 of 70 (11.4%) and only in participants aged <18 years; all had autologous reconstitution. After a median follow-up of 2.4 years, the 2-year Kaplan-Meier-based probability of event-free survival was 82.6%. The 2-year overall survival was 94.1%, with no difference between children and adult participants. After excluding participants with graft failure (n = 8), participants with engraftment had median whole blood donor chimerism values at days +180 and +365 after transplant of 100% (n = 58), respectively, and 96.6% (57/59) were off immunosuppression 1 year after transplant. The 1-year grade 3 to 4 acute graft-versus-host disease (GVHD) rate was 10%, and the 2-year moderate-severe chronic GVHD rate was 10%. Five participants (7.1%) died from infectious complications. We demonstrate that nonmyeloablative haploidentical BMT with thiotepa and PTCy is a readily available curative therapy for most adults, even those with organ damage, compared to the more expensive myeloablative gene therapy and gene editing. Additional strategies are required for children to decrease graft failure rates. The trial was registered at www.clinicaltrials.gov as #NCT01850108.

Hydroxyurea for secondary stroke prevention in children with sickle cell anemia in Nigeria: a randomized controlled trial.

We tested the hypothesis that fixed oral moderate-dose hydroxyurea (20 mg/kg per day) for initial treatment of secondary stroke prevention results in an 80% relative risk reduction of stroke or death when compared with fixed oral low-dose hydroxyurea (10 mg/kg per day) in a phase 3 double-blind, parallel-group, randomized controlled trial in children with sickle cell anemia (SCA) living in Nigeria. A total of 101 participants were randomly allocated to low-dose (n = 49) and moderate-dose (n = 52) hydroxyurea treatment groups. The median participant follow-up was 1.6 years (interquartile range, 1.0-2.3), with a planned minimum follow-up of 3.0 years. A total of 6 recurrent strokes and 2 deaths vs 5 recurrent strokes and 3 deaths occurred in the low- and moderate-dose groups, respectively. The incidence rate ratio (IRR) of the primary outcome measure of stroke or death in the low- and moderate-dose hydroxyurea treatment groups was 0.98 (95% confidence interval [CI], 0.32-3.00; P = .97). The trial was stopped early owing to no clinical difference in the incidence rates of the primary outcome measure. The incidence rates of recurrent strokes were 7.1 and 6.0 per 100 person-years in the low- and moderate-dose groups, respectively, (IRR, 1.18; 95% CI, 0.30-4.88; P = .74). As a measure of adherence to the oral hydroxyurea therapy, the median percent of returned pills was 3.0% and 2.6% in the low- and moderate-dose groups, respectively. No participant had hydroxyurea therapy stopped for myelosuppression. For children with SCA in low-income settings without access to regular blood transfusion therapy, initial low-dose hydroxyurea is a minimum known efficacious dose for secondary stroke prevention.

Transcranial doppler velocity in iron-deficient Nigerian children with sickle cell anemia.

Oral iron supplementation in iron deficient children with sickle cell anemia and normal transcranial Doppler ultrasound (TCD) velocities does not reduce arterial flow in the middle cerebral artery.

Heart rate variability associated with acute exercise challenge in children with sickle cell anaemia.

We examined heart rate variability (HRV) during exercise testing in 20 children with sickle cell anaemia (SCA) and 12 controls. Subjects achieved lower median HRV at peak exercise [standard deviation of R-wave to R-wave intervals (SDNN), 2·3 vs 2·9 ms, P = 0·027; logarithmic transformation of high frequency power (lnHF), 0·9 vs 1·3 ln(ms2 ), P = 0·047] and had lower post-exercise HRV across minute-by-minute analysis of recovery. After adjustment for haemoglobin, fitness and SCA status, subjects had lower HRV at the end of recovery with differences increasing as baseline HRV increased. Further investigation of HRV and exercise safety in SCA is warranted.

Cerebral and skeletal muscle tissue oxygenation during exercise challenge in children and young adults with sickle cell anaemia.

We used near-infrared spectroscopy to examine tissue oxygenation (StO2) during exercise in 17 children and young adults with sickle cell anaemia (SCA) and 13 controls. Patients had lower cerebral StO2 at all exercise stages and demonstrated significantly greater decreases in cerebral StO2 later during exercise. Quadriceps StO2 increased similarly in patients and controls during early exercise, but decreases from baseline were greater in patients during later exercise. At similar workloads, patients demonstrated lower cerebral StO2 (69·2 ± 6·6 vs. 79·5 ± 5·3%, P < 0·001) and trended towards lower quadriceps StO2 (67·7 ± 9·0 vs. 73·2 ± 7·9%, P = 0·09) . Further studies of tissue oxygenation during exercise in SCA are warranted.

Primary prevention of stroke in children with sickle cell anemia in sub-Saharan Africa: rationale and design of phase III randomized clinical trial.

Strokes in children with sickle cell anemia (SCA) are associated with significant morbidity and premature death. Primary stroke prevention in children with SCA involves screening for abnormal transcranial Doppler (TCD) velocity coupled with regular blood transfusion therapy for children with abnormal velocities, for at least one year. However, in Africa, where the majority of children with SCA live, regular blood transfusions are not feasible due to inadequate supply of safe blood, cost, and the reluctance of caregivers to accept transfusion therapy for their children. We describe the Primary Prevention of Stroke in Children with Sickle Cell Disease in Nigeria Trial [StrokePreventioninNigeria (SPRING) trial, NCT02560935], a three-center double-blinded randomized controlled Phase III clinical trial to 1) determine the efficacy of moderate fixed-dose (20 mg/kg/day) versus low fixed-dose (10 mg/kg/day) hydroxyurea therapy for primary stroke prevention; 2) determine the efficacy of moderate fixed-dose hydroxyurea for decreasing the incidence of all cause-hospitalization (pain, acute chest syndrome, infection, other) compared to low fixed-dose hydroxyurea. We will test the primary hypothesis that there will be a 66% relative risk reduction of strokes in children with SCA and abnormal TCD measurements, randomly allocated, for a minimum of three years to receive moderate fixed-dose versus low fixed-dose hydroxyurea (total n = 220). The results of this trial will advance the care of children with SCA in sub-Saharan Africa, while improving research capacity for future studies to prevent strokes in children with SCA.

Low educational level of head of household, as a proxy for poverty, is associated with severe anaemia among children with sickle cell disease living in a low-resource setting: evidence from the SPRING trial.

Severe anaemia, defined as haemoglobin level < 6·0 g/dl, is an independent risk factor for death in individuals with sickle cell disease living in resource-limited settings. We conducted a cross-sectional study of 941 children with sickle cell anaemia, who had been defined as phenotype HbSS or HbSß0 thalassaemia, aged five to 12 years, and were screened for enrollment into a large primary stroke prevention trial in Nigeria (SPRING; NCT02560935). The main aim of the study was to determine the prevalence and risk factors for severe anaemia. We found severe anaemia to be present in 3·9% (37 of 941) of the SPRING study participants. Severe anaemia was significantly associated with the lower educational level of the head of the household (P = 0·003), as a proxy for poverty, and a greater number of children per room in the household (P = 0·004). Body mass index was not associated with severe anaemia. The etiology of severe anaemia in children living with sickle cell anaemia in Nigeria is likely to be multifactorial with an interplay between an individual's disease severity and other socio-economic factors related to poverty.

Automated exchange compared to manual and simple blood transfusion attenuates rise in ferritin level after 1 year of regular blood transfusion therapy in chronically transfused children with sickle cell disease.

BACKGROUND: Optimal strategies for regular blood transfusion therapy are not well defined in sickle cell disease (SCD). This analysis tested the hypothesis that in the first of year of regular transfusions, when chelation therapy use is minimal, automated exchange transfusion would be the superior method for attenuating the rise in ferritin levels compared to simple and manual exchange transfusions. STUDY DESIGN AND METHODS: The Silent Cerebral Infarct Multi-Center Clinical Trial randomly allocated children with SCD and silent cerebral infarcts to receive standard care or regular transfusions with a target pre-transfusion HbS concentration ≤ 30% and minimum hemoglobin level > 9.0 g/dL. Participants with at least nine transfusions and sufficient ferritin testing in the first year of the trial were included in a planned secondary analysis. Ferritin levels by the end of the first study year were compared between participants receiving automatic exchange transfusion, manual exchange transfusion, and simple transfusion. RESULTS: A total of 83 participants were analyzed. During the first year of the study, 75.9% of the participants had >80% of transfusions via one transfusion method. At baseline no significant differences in ferritin levels were observed in the three transfusion groups (p = 0.1). After 1 year of transfusions the median (interquartile range) ferritin levels in the simple transfusion (n = 40), manual exchange transfusion (n = 34) and automatic exchange transfusion (n = 9) groups were 1800 ng/mL (1426-2204 ng/mL), 1530 ng/mL (1205-1805 ng/mL), and 355 ng/mL (179-579 ng/mL), respectively (p < 0.001). CONCLUSION: Automated exchange transfusion, when compared to other transfusion methods, is the optimal transfusion strategy for attenuating increase in ferritin levels in children with SCD.

Rate of Food Insecurity Among Households with Children with Sickle Cell Disease is Above the National Average.

OBJECTIVES: Despite studies demonstrating the negative impact of food insecurity on health in children, limited research has been done to assess the prevalence and sequelae of food insecurity in sickle cell disease (SCD). We tested the hypothesis that food insecurity is common in children with SCD and is associated with increased SCD morbidity. METHODS: Between May and November 2017, we conducted a single-center cross-sectional study using the previously validated, self-administered, US 18-item household food security survey module and the 9-item youth (12-17 years old) food security survey module during regular outpatient clinic visits. We also included the incidence of vaso-occlusive pain or acute chest syndrome requiring hospitalizations in the year before the questionnaire. RESULTS: A total of 75 caregivers and 24 children completed the surveys. The median age of the children was 10.4 years (interquartile range 5.5-15.3), 46.7% were boys. The rate of household food insecurity was 21.3% (16 of 75). Among the 24 children who completed the youth survey, 45.8% were classified as food insecure. Discordance occurred between caregivers' and children's assessment of food insecurity. A total of 81.8% (9 of 11) children reported being food insecure, whereas their caregivers reported to be food secure. The incidence for pain and acute chest syndrome in the year pre-enrollment was not different between food-secure and food-insecure children (59.3 and 43.8/100 patient-years, P = 0.54; 8.5 and 12.5/100 patient-years, P = 0.49, respectively). CONCLUSIONS: In a tertiary care medical center in Tennessee, one in five households with children with SCD were assessed as food insecure, with a substantial discordance between caregiver and child assessment of food insecurity.

Multidisciplinary care results in similar maternal and perinatal mortality rates for women with and without SCD in a low-resource setting.

In Africa, the maternal mortality rate in sickle cell disease (SCD) is ~10%. Our team previously demonstrated an 89% decrease in mortality rate in a before-and-after feasibility study among women with SCD living in low-resource setting in Ghana. In the same cohort including additional participants with and without SCD, we used a prospective cohort design to test the hypothesis that implementing a multidisciplinary care team for pregnant women with SCD in low-resource setting will result in similar maternal and perinatal mortality rates compared to women without SCD. We prospectively enrolled pregnant women with and without SCD or trait and followed them up for 6-week postpartum. We tested the newborns of mothers with SCD for SCD. We recruited age and parity matched pregnant women without SCD or trait as the comparison group. Maternal and perinatal mortality rates were the primary outcomes. A total of 149 pregnant women with SCD (HbSS, 54; HbSC, 95) and 117 pregnant women without SCD or trait were included in the analysis. Post-intervention, maternal mortality rates were 1.3% and 0.9% in women with and without SCD, respectively (P = 1.00); the perinatal mortality rates were 7.4% and 3.4% for women with and without SCD, respectively (P = 0.164). Among the mothers with SCD, ~15% of newborns had SCD. Multidisciplinary care of pregnant women with SCD may reduce maternal and perinatal mortality rates to similar levels in pregnant women without SCD in low-resource settings. Newborns of mothers with SCD have a high rate of SCD.

Asthma in children with sickle cell disease.

PURPOSE OF REVIEW: Asthma is common in children with sickle cell disease (SCD) and appears to be associated with increased morbidity. Providers caring for children with SCD have struggled with the question of whether asthma exists as a true comorbidity or whether certain aspects of the chronic inflammatory disease gives children with SCD an asthma-like phenotype. RECENT FINDINGS: Clinical signs and symptoms seen in children with asthma in the general population, such as wheezing, airway hyperresponsiveness, atopy, elevated leukotrienes, and abnormal lung function are seen in children with SCD both with and without a diagnosis of asthma. SUMMARY: Current evidence highlights that the presence of lung disease in children with SCD has significant implications irrespective of the underlying cause, including asthma. Further research should focus on well tolerated and effective interventions to prevent disease-related complications for children with pulmonary complications of SCD.

Integrated psychology support and comprehensive cognitive evaluation improves access to special education services for children with sickle cell disease.

BACKGROUND: Children with sickle cell disease (SCD) are at risk for cognitive deficits. Limited data describe whether comprehensive cognitive evaluation improves education resources and whether caregivers perceive the assessment as beneficial. We tested our two hypotheses: (a) an integrated comprehensive cognitive evaluation program in children with SCD results in increased special education services allocation; and (b) caregivers will value comprehensive cognitive evaluation services provided. PROCEDURE: In a tertiary care medical facility, as part of quality improvement project, in a before-and-after evaluation between March 2011 and July 2014, we examined the impact of targeted comprehensive cognitive evaluation on change in special education services. We also evaluated the caregiver's perception regarding the utility of the provided services. RESULTS: A total of 21% (42 of 196) students (median age 11 years, range 3-18) with SCD were referred for cognitive assessment due to overt stroke (n = 11), silent stroke (n = 14), or concerns about cognitive or academic functioning without evidence of strokes (n = 17). At baseline, 45.2% received special education services and after the comprehensive cognitive evaluation 86.7% received special education services (P < 0.001). Among 33 caregivers who completed the survey, 97% reported that the assessment was helpful and 60% indicated that assessment led to beneficial changes for their children at school. CONCLUSION: Education advocacy coupled with comprehensive cognitive assessment in students with SCD improved access to special education services, and caregivers uniformly endorse this service as having added value.

Increased Patient Activation Is Associated with Fewer Emergency Room Visits and Hospitalizations for Pain in Adults with Sickle Cell Disease.

OBJECTIVE: Recurrent vaso-occlusive pain episodes, the most common complication of sickle cell disease (SCD), cause frequent health care utilization. Studies exploring associations between patient activation and acute health care utilization for pain are lacking. We tested the hypothesis that increased activation and self-efficacy are associated with decreased health care utilization for pain in SCD. METHODS: In this cross-sectional study of adults with SCD at a tertiary medical center, we collected demographics, SCD phenotype, Patient Activation Measure levels, and self-efficacy scores using structured questionnaires. We reviewed charts to obtain disease-modifying therapy and acute health care utilization, defined as emergency room visits and hospitalizations, for vaso-occlusive pain episodes. Negative binomial regression analyses were used to test the hypothesis. RESULTS: We surveyed 67 adults with SCD. The median age was 27.0 years, 53.7% were female, and 95.5% were African American. Median health care utilization for pain over one year (range) was 2.0 (0-24). Only one-third of participants (38.8%) were at the highest activation level (median [range] = 3 [1-4]). Two-thirds (65.7%) of participants had high self-efficacy (median [range] = 32.0 [13-45]). Regressions showed significant association between health care utilization and activation (incidence rate ratio [IRR] = 0.663, P = 0.045), self-efficacy (IRR = 0.947, P = 0.038), and male sex (IRR = 0.390, P = 0.003). Two outliers with high activation, self-efficacy, and health care utilization also had addictive behavior. CONCLUSIONS: Many individuals with SCD have suboptimal activation and reduced self-efficacy. Higher activation and self-efficacy were associated with lower health care utilization for pain. Additional studies are needed to evaluate interventions to improve activation and self-efficacy and reduce acute health care utilization for pain.

Contraceptive Methods and the Impact of Menstruation on Daily Functioning in Women with Sickle Cell Disease.

OBJECTIVES: Women with sickle cell disease (SCD) are living longer as a result of advances in the care of their underlying disease. With the population growing of women living with SCD, reproductive health issues in this population have become an emphasized area of medical care. We sought to describe current patterns of contraception use, menstruation, and quality-of-life (QOL) measures in women with SCD. METHODS: Using a cross-sectional study design, we administered paper surveys at two academic medical centers to women aged 10 to 55 years with SCD to capture current contraceptive use, characteristics of menstrual cycles, and QOL metrics. RESULTS: Of the 103 women who participated, 12.7% (13/102) experienced a duration of menses >7 days (defined here as prolonged menstrual bleeding). Approximately half of women (51.5%, 53/103) used some form of contraception, with depot medroxyprogesterone acetate injections and condoms being the most common. During their last menstrual periods, women with both dysmenorrhea and prolonged menstrual bleeding (6.9%, 7/102) were more likely to experience more days of poor QOL, with more nights with sleep disturbance (P = 0.001) and more days with trouble taking care of themselves (P = 0.003), as well as being unable to do things they previously enjoyed (P = 0.001), compared with those with neither phenomenon (28.2%, 29/103). CONCLUSIONS: Dysmenorrhea and prolonged menstrual bleeding negatively affect the QOL of women with SCD. Menstrual histories and preventive measures for menstruation-related morbidity should be incorporated into routine evaluations of women with SCD.

Aeroallergen sensitization predicts acute chest syndrome in children with sickle cell anaemia.

Asthma is associated with higher rates of acute chest syndrome (ACS) and vaso-occlusive pain episodes among children with sickle cell anaemia (SCA). Aeroallergen sensitization is a risk factor for asthma. We hypothesized that aeroallergen sensitization is associated with an increased incidence of hospitalizations for ACS and pain. Participants in a multicentre, longitudinal cohort study, aged 4-18 years with SCA, underwent skin prick testing to ten aeroallergens. ACS and pain episodes were collected from birth until the end of the follow-up period. The number of positive skin tests were tested for associations with prospective rates of ACS and pain. Multivariable models demonstrated additive effects of having positive skin tests on future rates of ACS (incidence rate ratio (IRR) for each positive test 1·23, 95% confidence interval [CI] 1·11-1·36, P < 0·001). Aeroallergen sensitization was not associated with future pain (IRR 1·14, 95%CI 0·97-1·33, P = 0·11). Our study demonstrated that children with SCA and aeroallergen sensitization are at increased risk for future ACS. Future research is needed to determine whether identification of specific sensitizations and allergen avoidance and treatment reduce the risk of ACS for children with SCA.

Exercise capacity and clinical outcomes in adults followed in the Cooperative Study of Sickle Cell Disease (CSSCD).

OBJECTIVES: To determine the factors associated with exercise capacity in adults with sickle cell disease (SCD) and its relationship to hospitalizations and mortality. METHODS: A total of 223 participants in the Cooperative Study of Sickle Cell Disease (CSSCD) (64% female, 70% hemoglobin SS/Sß0 thalassemia, mean age 43.3 ± 7.5 years) underwent maximal exercise testing using a treadmill protocol with a mean duration of 11.6 ± 5.2 minutes. RESULTS: Female sex (ß = -3.34, 95% CI [-1.80, -4.88], P < 0.001), older age (ß = -0.14, 95% CI [-0.24, -0.04], P = 0.005), higher body mass index (ß = -0.23, 95% CI [-0.37, -0.10]; P = 0.001), and lower hemoglobin (ß = 0.56, 95% CI [0.08, 1.04], P = 0.02) were independently associated with lower fitness, while there was a trend with abnormal pulmonary function testing (ß = -1.42, 95% CI [-2.92, 0.07]; P = 0.06). Lower percent-predicted forced expiratory volume in 1 second (FEV1 ) was independently associated with lower fitness (ß = 0.08, 95% CI [0.03, 0.13], P = 0.001). Genotype and hospitalization rates for pain and acute chest syndrome (ACS) prior to testing were not associated with exercise capacity. Baseline exercise capacity predicted neither future pain or ACS nor survival in our cohort. Adults with SCD tolerated maximal exercise testing. CONCLUSIONS: Prospective studies are needed to further evaluate the impact of regular exercise and improved fitness on clinical outcomes and mortality in SCD.

Sleep disordered breathing does not predict acute severe pain episodes in children with sickle cell anemia.

Conflicting evidence has suggested that low mean nocturnal hemoglobin oxygen saturation (SpO2 ) predicts future hospital days for acute severe pain in children with sickle cell anemia (SCA). In an unselected multicenter prospective cohort study, we tested the hypothesis that either low mean nocturnal SpO2 or high obstructive apnea-hypopnea index (OAHI; the number of obstructive apneas and hypopneas with ≥ 3% desaturation or arousal per hour of sleep) or high oxygen desaturation index (ODI; number of ≥ 3% desaturation from baseline saturation per hour of sleep) is associated with increased incidence rates of pain. A total of 140 children with SCA with a median age of 10.8 years (interquartile range 7.2) were followed for a median of 4.9 years (interquartile range 1.8). Overnight polysomnography evaluations at baseline health exam were measured and adjudicated centrally. Multivariable models created in two steps were included. First, all plausible covariates were included in a screening model. Subsequently, covariates meeting level of statistical significance of P < .20 were included in the final model. Contrary to our hypothesis, higher (but not lower) mean nocturnal SpO2 was associated with higher rates of pain episodes (Incidence rate ratio (IRR) 1.10, 95% CI [1.03-1.18], P = .004). Higher log OAHI did not pass screening criteria. Higher log ODI was not significantly associated with higher rates of pain episodes (IRR 0.93, 95% CI [0.82-1.06], P = .28). Neither low nocturnal SpO2, higher OAHI, nor higher ODI were associated with clinically relevant increased incidence rates of acute severe pain episodes.

Clustering of end-organ disease and earlier mortality in adults with sickle cell disease: A retrospective-prospective cohort study.

Chronic end-organ complications result in morbidity and mortality in adults with sickle cell disease (SCD). In a retrospective-prospective cohort of 150 adults with SCD who received standard care screening for pulmonary function abnormalities, cardiac disease, and renal assessment from January 2003 to 2016, we tested the hypothesis that clustering of end-organ disease is common and multiple organ impairment predicts mortality. Any end-organ disease occurred in 59.3% of individuals, and 24.0% developed multiple organ (>1) end-organ disease. The number of end-organs affected was associated with mortality (P ≤ .001); 8.2% (5 of 61) of individuals with no affected end-organ, 9.4% (5 of 53) of those with 1 affected organ, 20.7% (6 of 29) of those with 2 affected end-organs, and 85.7% (6 of 7) with 3 affected end-organs died over a median follow up period of 8.7 (interquartile range 3.5-11.4) years. Of the 22 individuals who died, 77.3% had evidence of any SCD-related end-organ impairment, and this was the primary or secondary cause of death in 45.0%. SCD-related chronic impairment in multiple organs, and its association with mortality, highlights the need to understand the common mechanisms underlying chronic end-organ damage in SCD, and the urgent need to develop interventions to prevent irreversible end-organ complications in SCD.

Age is a predictor of a small decrease in lung function in children with sickle cell anemia.

The longitudinal pattern of lung function in children with sickle cell anemia (SCA) has shown a decrease in FEV1 % predicted, a risk factor for death in adults with SCA, but predictors for this decline are poorly characterized. In a prospective longitudinal multi-center cohort of children with SCA, we tested the hypotheses that: (1) FEV1 % predicted declines over time; and (2) SCA-specific characteristics and therapy predict this decline. At three clinical centers, children with SCA (HbSS or HbSß0 thalassemia), unselected for respiratory disease, were enrolled in the Sleep and Asthma Cohort (SAC) study. Study-certified pulmonary function technicians performed spirometry and lung volumes. Each assessment was reviewed centrally. Predicted values were determined for TLC, FEV1 , FVC, and FEV1 /FVC ratio. A total of 197 participants, mean age 11.0 years at first testing (range 4-19.3 years), had a minimum of three spirometry measurements, over an average of 4.4 years (range 1.1-6.5 years) from baseline to endpoint. In a multivariable model, FEV1 % predicted declines by 0.3% for every additional year of age (95% CI -0.56 to -0.05, P = .020). Sex, asthma history, hemoglobin, reticulocyte count, white blood cell count, incidence rate of severe acute pain and acute chest syndrome episodes, and hydroxyurea therapy were not associated with a decline in FEV1 % predicted. In a large, rigorously evaluated, prospective cohort of an unselected group of children with SCA, FEV1 % predicted declines minimally over an average of 4 years, and none of the examined disease features predict the decline.

Children with sickle cell anemia with normal transcranial Doppler ultrasounds and without silent infarcts have a low incidence of new strokes.

In a prospective cohort study, we tested the hypothesis that children with sickle cell anemia (SCA) with normal transcranial Doppler ultrasound (TCD) velocities and without silent cerebral infarcts (SCIs) would have a lower incidence rate of new neurological events (strokes, seizures or transient ischemic attacks) compared to children with normal TCD measurements and SCIs, not receiving regular blood transfusions. Nonrandomized participants from the silent cerebral infarct transfusion (SIT) Trial who had screening magnetic resonance imaging (MRI) of the brain and normal TCD measurements were included. Follow-up ended at the time of first neurological event (stroke, seizure or transient ischemic attack), start of regular blood transfusion, or loss to follow-up, whichever came first. The primary endpoint was a new neurological event. Of 421 participants included, 68 had suspected SCIs. Mean follow-up was 3.6 years. Incidence rates of new neurological events in nontransfused participants with normal TCD values with SCIs and without SCIs were 1.71 and 0.47 neurological events per 100 patient-years, respectively, P = .065. The absence of SCI(s) at baseline was associated with a decreased risk of a new neurological event (hazard ratio 0.231, 95% CI 0.062-0.858; P = .029). Local pediatric neurologists examined 67 of 68 participants with suspected SCIs and identified 2 with overt strokes classified as SCIs by local hematologists; subsequently one had a seizure and the other an ischemic stroke. Children with SCA, without SCIs, and normal TCD measurements have a significantly lower rate of new neurological events when compared to those with SCIs and normal TCD measurements. Pediatric neurology assessment may assist risk stratification.