Predictive validity of developmental screening in young children with sickle cell disease: a longitudinal follow-up study.

AIM: To assess the predictive validity of developmental screenings in children with sickle cell disease (SCD) for academic outcomes and stroke risk. METHOD: Parent questionnaires and medical record data were collected for a cohort receiving developmental screenings between September 2004 and May 2008 as toddlers or early school age. Screening outcomes were dichotomized (positive, negative) by a priori criteria. Questionnaires assessed school and social functioning, services received, and quality of life. Medical record data assessed general SCD morbidity and stroke risk. RESULTS: Forty-one toddlers (mean age 2y 5mo; 25 males, 16 females) and 49 early school-age children (mean age 6y 5mo; 26 males, 23 females) completed follow-up. The mean follow-up period was 8 years 6 months (range 6.1-10.8y). For toddlers, positive screenings for language delays predicted lower academic performance (p=0.023). For older children, positive screenings for cognitive delays predicted more frequent academic/attentional problems at school (p<0.001), grade retention (p=0.007), and lower academic performance (p=0.001). Positive screenings were associated with an earlier onset of school problems and lower quality of life. Positive screenings for language/cognitive delays predicted increased stroke risk (both p<0.05). INTERPRETATION: Screening for language or cognitive development in young children with SCD predicts academic outcomes and stroke risk. WHAT THIS PAPER ADDS: Developmental screening predicts academic outcomes in sickle cell disease. Children with concerning language/cognitive screenings have early-onset school difficulties. Developmental screenings may help predict cerebrovascular complications.

Comorbid obstructive sleep apnea and increased risk for sickle cell disease morbidity.

PURPOSE: Sickle cell disease (SCD) imparts an increased risk for obstructive sleep apnea (OSA) in childhood. Studies of pediatric SCD have identified an increased risk for pain and neurologic complications with comorbid OSA. We determined the rate of a broad range of SCD-related medical complications to better characterize the spectrum of SCD complications related to OSA. METHODS: Retrospective chart review at a single hematology clinic identified 641 youth with SCD who received consistent screenings for OSA as part of routine hematological health maintenance visits over an 11-year period. Medical complication rates in the 136 children with OSA determined by polysomnography exams were compared to 136 matched controls at lower risk for OSA due to negative OSA screenings or exams. RESULTS: Children with SCD and OSA had higher overall rates of SCD complications than low OSA-risk controls; lung morbidity showed the largest effect size. Infection, cardiovascular, and neurologic complications occurred at higher rates in children with OSA. Children with comorbid OSA had higher rates of SCD complications both before and after OSA diagnosis. CONCLUSIONS: OSA in children with SCD is associated with higher rates of a broad range of SCD complications, including pneumonia and acute chest syndrome. Routine screenings, diagnosis, and increased therapeutic intervention for children with comorbid OSA could decrease SCD morbidity.

Parent Perspectives on Pain Management in Preschool-Age Children With Sickle Cell Disease.

Pain episodes occur for many preschoolers with sickle cell disease (SCD), but little is known about parent perceptions of managing pain episodes in young children. We surveyed parents of young children with SCD who had managed pain episodes in the past year to assess their management and satisfaction with their strategies, challenges of pain management, and interest in additional education. Parents were recruited from health maintenance visits at a SCD specialty clinic. Forty-two of 51 parents (82%) of 2- to-6-year-olds reported managing pain over the past year. Parents who had managed pain primarily reported using medications. These parents reported at least moderate satisfaction with current management strategies and resources. At least one-third of parents found each facet of pain management queried as at least somewhat challenging. Identifying when their child was in pain, encouraging functional activities, and managing irritable behavior were reported as most challenging. Parents of young children with SCD reported interest in additional pain management education, which could promote better parent and child coping skills.

Developmental Screening in Pediatric Sickle Cell Disease: Disease-Related Risk and Screening Outcomes in 4 Year Olds.

OBJECTIVE: Studies of early child development in sickle cell disease (SCD) have found modest associations between disease-related risks and developmental status in infants and toddlers, but such associations are evident by early elementary school. We screened 4-year-old children with SCD using 2 screening strategies to assess if biomedical risk factors for neurologic disease are related to developmental screening outcomes at this intermediate age. METHODS: Seventy-seven 4-year-old children with SCD (M = 4.5 yrs, SD = 0.3 yrs) completed developmental screenings at routine hematology visits using child testing (Fluharty Preschool Speech and Language Screenings Test, 2nd edition) and parent-report (Ages and Stages Questionnaire, 2nd edition) procedures. Genotype and other biomedical variables were coded from medical records. RESULTS: Children with higher-risk SCD genotypes (n = 52) showed lower performance than children with lower-risk genotypes (n = 25) on a measure related to neurologic disease risk in older children (syntactic processing); genotype risk was also related to rates of positive screenings on parent-reported developmental milestones (52% positive screenings in high-risk genotypes vs 12% in low-risk genotypes). Screening outcomes were also related to transcranial Doppler ultrasound findings assessing cerebral blood flow. CONCLUSION: Developmental screening at age 4 may be a useful target age for identifying preschoolers with sickle cell-related neurodevelopmental concerns. Parent report of developmental milestones and behavioral testing each may have a role in screening for children in need of follow-up services to address potential neurodevelopmental effects from SCD.

Genetic Modifiers of White Blood Cell Count, Albuminuria and Glomerular Filtration Rate in Children with Sickle Cell Anemia.

Discovery and validation of genetic variants that influence disease severity in children with sickle cell anemia (SCA) could lead to early identification of high-risk patients, better screening strategies, and intervention with targeted and preventive therapy. We hypothesized that newly identified genetic risk factors for the general African American population could also impact laboratory biomarkers known to contribute to the clinical disease expression of SCA, including variants influencing the white blood cell count and the development of albuminuria and abnormal glomerular filtration rate. We first investigated candidate genetic polymorphisms in well-characterized SCA pediatric cohorts from three prospective NHLBI-supported clinical trials: HUSTLE, SWiTCH, and TWiTCH. We also performed whole exome sequencing to identify novel genetic variants, using both a discovery and a validation cohort. Among candidate genes, DARC rs2814778 polymorphism regulating Duffy antigen expression had a clear influence with significantly increased WBC and neutrophil counts, but did not affect the maximum tolerated dose of hydroxyurea therapy. The APOL1 G1 polymorphism, an identified risk factor for non-diabetic renal disease, was associated with albuminuria. Whole exome sequencing discovered several novel variants that maintained significance in the validation cohorts, including ZFHX4 polymorphisms affecting both the leukocyte and neutrophil counts, as well as AGGF1, CYP4B1, CUBN, TOR2A, PKD1L2, and CD163 variants affecting the glomerular filtration rate. The identification of robust, reliable, and reproducible genetic markers for disease severity in SCA remains elusive, but new genetic variants provide avenues for further validation and investigation.

Examining Biopsychosocial Factors in Relation to Multiple Pain Features in Pediatric Sickle Cell Disease.

OBJECTIVE: To examine biopsychosocial variables in relation to multiple pain features in pediatric sickle cell disease (SCD). METHODS: 76 children with SCD (M = 14.05, SD = 3.26), ages 8-19 years, and 70 caregivers completed measures of coping, mood, and family functioning and reported on multiple pain features via retrospective interviews during routine hematological visits. Sickle cell genotype and health care utilization were collected via medical record review. Using hierarchical regression, biological (genotype), child psychological (coping and mood), and social factors (caregiver coping and family functioning) were evaluated in relation to multiple pain features. RESULTS: Genotype was associated with pain intensity, and child psychological factors were associated with pain frequency. Multiple biopsychosocial factors were related to health care utilization. CONCLUSIONS: Biopsychosocial factors may have distinct relationships with pain features in pediatric SCD. Understanding these relationships may refine the biopsychosocial model and inform integrated medical and psychosocial approaches in SCD.

Association between somatic growth trajectory and cognitive functioning in young children with sickle cell disease.

Children with sickle cell disease are at risk of cognitive deficits and somatic growth delays beginning in early childhood. We examined growth velocity from age 2 years (height and body mass index progression over time) and cognitive functioning in 46 children with sickle cell disease 4 to 8 years of age. Height-for-age velocity was not associated with cognitive outcomes. Higher body mass index velocity was associated with higher scores on global cognitive and visual-motor abilities but not processing resources or academic achievement. Body mass index progression over time may be a clinically useful indicator of neurocognitive risk in sickle cell disease, as it may reflect multiple sickle cell disease-related risk factors.

Changes in coping, pain, and activity after cognitive-behavioral training: a randomized clinical trial for pediatric sickle cell disease using smartphones.

OBJECTIVES: We examined the outcomes of a cognitive-behavioral therapy (CBT) intervention for pain in pediatric sickle cell disease (SCD) using smartphones as a novel delivery method. MATERIALS AND METHODS: Forty-six children with SCD received CBT coping skills training using a randomized, waitlist control design. The intervention involved a single session of CBT training and home-based practice using smartphones for 8 weeks. Pre-post questionnaires between the randomized groups were used to evaluate changes in active psychological coping and negative thinking using the Coping Strategies Questionnaire. Daily diaries completed by the full sample during the treatment period were used to assess whether CBT skill use was related to reductions in next-day pain intensity and increases in same-day functional activity. RESULTS: The pre-post group comparison suggested that the youth increased active psychological coping attempts with the intervention. Daily diary data indicated that when children used CBT skills on days with higher pain, there were reductions in next-day pain intensity. There was no such association between skill use and functional activity. DISCUSSION: CBT coping skills training supported using smartphones can increase coping and reduce pain intensity for children with SCD; however, additions to the study protocols are recommended in future studies. Advantages and caveats of using smartphones are also discussed.

Information-seeking coping behaviors during painful procedures in African-American children with sickle cell disease.

This study examined the frequency of information-seeking coping behaviors in 37 African-American children (ages 5-17 years) with sickle cell disease during venipuncture. The relationships between coping behaviors and child- and parent-reported pain and observational distress were also assessed. The majority of children attended to the procedure, but did not seek information via questions. This pattern of coping was only partially effective at reducing distress and had no relation to pain. This pattern of coping is discussed within the context of cultural factors that may be important in understanding responses to procedural pain in pediatric sickle cell disease.

Sensitization to acute procedural pain in pediatric sickle cell disease: modulation by painful vaso-occlusive episodes, age, and endothelin-1.

UNLABELLED: The impact of pain early in life is a salient issue for sickle cell disease (SCD), a genetic condition characterized by painful vaso-occlusive episodes (VOEs) that can begin in the first year of life and persist into adulthood. This study examined the effects of age and pain history (age of onset and frequency of recent VOEs) on acute procedural pain in children with SCD. Endothelin-1, a vaso-active peptide released during VOEs and acute tissue injury, and its precursor, Big Endothelin, were explored as markers of pain sensitization and vaso-occlusion. Sixty-one children with SCD (ages 2 to 18) underwent venipuncture at routine health visits. Procedural pain was assessed via child and caregiver reports and observational distress. Pain history was assessed using retrospective chart review. Three primary results were found: 1) younger age was associated with greater procedural pain across pain outcomes; 2) higher frequency of VOEs was associated with greater procedural pain based on observational distress (regardless of age); and 3) age was found to moderate the relationship between VOEs and procedural pain for child-reported pain and observational distress for children 5 years of age and older. Associations between the endothelin variables and pain prior to venipuncture were also observed. PERSPECTIVE: For children with SCD, the child's age and recent pain history should be considered in procedural pain management. The endothelin system may be involved in preprocedure pain, but additional research is needed to understand the role of endothelins in pain sensitization.

Responsiveness of the PedsQL to pain-related changes in health-related quality of life in pediatric sickle cell disease.

OBJECTIVE: To determine if caregiver report of the pediatric quality of life inventory (PedsQL) is responsive to changes in health-related quality of life (HRQL) associated with pain episodes in pediatric sickle cell disease (SCD). METHODS: 81 caregivers of children ages 2-19 years with SCD completed the PedsQL as part of routine psychosocial screenings at 2 time points, ranging from 6 to 18 months apart. Frequency of SCD-related pain episodes between time points was assessed using medical chart review. RESULTS: The frequency of pain episodes between time points was a significant predictor of decreases in physical, psychosocial, and total HRQL, even after controlling for time interval, demographic, and medical variables. CONCLUSIONS: The caregiver report of the PedsQL appears to be a useful tool for capturing changes in HRQL over time associated with pain episodes in SCD.

Cerebral blood flow velocity and language functioning in pediatric sickle cell disease.

We investigated the association of increased cerebral blood flow velocity with specific language abilities in children with sickle cell disease (SCD). Thirty-nine children ages 5 to 8 years old with high-risk genotypes of SCD underwent cognitive testing, which included tests of language skills, visual motor skills, and attention/working memory as part of a routine hematology health-maintenance visit. Transcranial Doppler (TCD) velocities were obtained from review of medical records, with the velocities that were in closest temporal proximity to the cognitive assessment used in the analysis. TCD velocities predicted scores on tests of syntactical skills, even when controlling for anemia severity. Semantic and phonological ability and other cognitive skills were not strongly related to TCD velocities. Elevated blood flow velocities in children with high-risk SCD may contribute to a specific language impairment or to a broader dysfunction of short-term and/or working memory. This study underscores the need for clinicians to monitor language skills of children with SCD who have elevated TCD velocities, as these cognitive abilities might be particularly sensitive to cerebrovascular disruption related to their disease.

Relationships between somatic growth and cognitive functioning in young children with sickle cell disease.

OBJECTIVE: Children with sickle cell disease (SCD) exhibit poor somatic growth due to nutritional and metabolic effects, but potential relationships between growth and other areas of development are unclear. We examined whether growth is related to cognition and whether growth might be one marker of neurocognitive risk. METHODS: Sixty-four children with SCD and eighty-one demographically similar controls, ages 4 to 8 years, completed cognitive and anthropometric measures. RESULTS: Height-for-age partially accounted for cognitive decrements related to SCD on all cognitive measures. Higher body-mass-index was a significant predictor of higher visual-motor and academic achievement scores in children with SCD, but not in controls. CONCLUSIONS: In some children with SCD, especially those with HbSS and Hb Sbeta(0), low height-for-age may help to explain neurocognitive risk. Higher body-mass-index may be related to better cognitive outcomes in children with SCD. Nutrition deficits in SCD could explain the association between somatic growth and cognitive deficits.

Criterion and convergent validity for 4 measures of pain in a pediatric sickle cell disease population.

OBJECTIVE: To evaluate the psychometric properties of 4 measures of acute pain in youth with sickle cell disease (SCD) during a medical procedure. METHODS: Heart rate, child self-report, parent proxy-report, and observable pain behaviors were examined in 48 youth with SCD ages 2 to 17 years. Criterion validity for acute pain was assessed by responsiveness to a standardized painful stimulus (venipuncture) in a prospective pre-post design. Convergent validity was evaluated through the correlation across measures in reactivity to the stimulus. RESULTS: Child self-reported pain, parent proxy-report, and behavioral distress scores increased in response to venipuncture (concurrent and convergent validity). In contrast, heart rate did not reliably change in response to venipuncture. Extent of change in response to venipuncture showed moderate intercorrelation across child and parent pain ratings, and behavioral distress. Preprocedure pain ratings correlated with pain experienced during the procedure. An item analysis of observable pain behaviors suggested differences in the presentation of pain in SCD compared with previous pediatric research. CONCLUSIONS: Criterion and convergent validity were demonstrated for child-report, parent-report, and observable pain behaviors. These measures seem to tap into distinct, yet overlapping aspects of the pain experience. Assessment of acute procedural pain responses in SCD requires evaluation of preprocedural pain due to the frequent presence of low-level, baseline pain.

Language processing deficits in sickle cell disease in young school-age children.

Verbal IQ deficits are frequently reported for school-age children with sickle cell disease (SCD), yet the profile of language abilities in SCD is unclear. We examined semantic, syntactic, and phonological processing in five-to-seven-year-olds at high neurologic risk based on SCD subtype (N = 33), at low neurologic risk with SCD (N = 21), and without SCD (N = 54). Low-risk SCD did not show language processing deficits. High-risk SCD showed deficits in all three language domains. Language processing deficits in SCD at the start of middle childhood are related to neurologic risks and include language skills beyond vocabulary.

Use of handheld wireless technology for a home-based sickle cell pain management protocol.

PURPOSE: To evaluate use of a handheld electronic wireless device to implement a pain management protocol for participants with sickle cell disease (SCD). METHODS: Participants were 19 patients with SCD aged 9-20 who experienced vaso-occlusive pain. A single-session training on the use of cognitive-behavioral coping skills was followed by instruction on how to practice these skills and monitor daily pain experience using the device. Daily pain experience and practice of coping skills were collected for the 8-week intervention period using wireless technology. RESULTS: High rates of participation, daily diary completion and consumer satisfaction support the use of handheld wireless devices to implement this protocol. A comparison of the rates of self and device-recorded skills practice provides important information about the use of electronic monitoring for behavioral interventions. CONCLUSION: Wireless data transfer technology has significant potential to become a practical method to improve symptom monitoring and communication between patients and providers.

Validity of the Pediatric Quality Of Life Inventory for youth with sickle cell disease.

OBJECTIVE: Evaluate the validity of the Pediatric Quality of Life Inventory (PedsQL) for sickle cell disease (SCD). METHODS: Sixty-eight parent-child dyads (children 5-18 years) completed the PedsQL. Medical record review assessed history of specific morbidities. RESULTS: Internal consistency of the scales varied. The strongest reliability was for parent proxy-report for specific domains or for global functioning scores with either informant. Modest internal consistency was found for specific domains with child informants, particularly for younger children. Moderate convergent validity was found between informants. History of neurologic problems or major pain episodes indicated criterion validity for specific scales. CONCLUSIONS: The PedsQL appears to validly assess quality of life in youth with SCD. Domain-specific measurement of quality of life was limited by (a) low reliability for youth-report and (b) lack of discriminant validity. Choice of informant may be important when evaluating quality of life effects from pain or neurologic problems in SCD.

Neurodevelopmental screening in toddlers and early preschoolers with sickle cell disease.

Sickle cell disease is associated with an elevated risk for neurologic complications beginning in early childhood. Detecting higher-risk cases with developmental screening instruments may be a cost-effective method for identifying young children in need of more frequent or intensive assessment. We evaluated the validity of the Denver II test as a tool to detect lower levels of developmental attainment and their association with neurologic risk in 50 young children with sickle cell disease. Children with suspect Denver II outcomes showed lower scores for functional communication skills, had lower hematocrit percentage, higher mean velocities on transcranial Doppler ultrasound imaging, and were more likely to have had preterm birth. Validity of age equivalencies from specific Denver II areas was demonstrated for Language and Fine Motor scores, suggesting the instrument could be used to index children's developmental levels in these domains. The Denver II may be a useful behavioral screening tool for neurodevelopmental risk in sickle cell disease.

Neurobehavioral impact of sickle cell disease in early childhood.

The physical effects of sickle cell disease (SCD) begin in infancy or early childhood, yet most behavioral studies have focused on school-age children. We evaluated the impact of higher versus lower neurologic risk on language, motor abilities, executive functions, and temperament in toddlers and early preschoolers with SCD. Thirty-nine children with higher risk SCD were compared to 22 children with lower risk SCD. Language and motor abilities were lower in older compared with younger children but were unrelated to sickle cell subgroups. Executive functions, particularly working memory, were poorer in children with higher risk SCD regardless of age. Parent-reported activity level was also lower in children with higher risk. Specific behavioral influences of SCD are evident early in childhood and include working memory decrements. Executive function deficits in SCD can emerge early in life and may be an important context for other areas of cognitive and behavioral development.

The association of oral hydroxyurea therapy with improved cognitive functioning in sickle cell disease.

This study examined potential cognitive benefits of oral hydroxyurea therapy for children with sickle cell disease (SCD). Cognitive abilities of 15 children with SCD on hydroxyurea were compared to 50 other children with SCD, controlling for demographics and hematocrit. Children on hydroxyurea scored significantly higher on tests of verbal comprehension, fluid reasoning, and general cognitive ability than children not on the drug. The data therefore provide preliminary evidence of cognitive benefits of hydroxyurea. Mechanisms for this effect may be improved blood/oxygen supply to the brain or reduced fatigue and illness.