Provision of pneumococcal prophylaxis for publicly insured children with sickle cell disease

Characterisation of medical conditions of children with sickle cell disease in the USA: findings from the 2007-2018 National Health Interview Survey (NHIS)

OBJECTIVES

We used the National Health Interview Survey (NHIS) data set to examine the prevalence of comorbid medical conditions; explore barriers to accessing healthcare and special educational services; and assess the associations between sickle cell disease (SCD) status and demographics/socioeconomic status (SES), and social determinants of health (SDoH) on comorbidities among children in the USA.

DESIGN

Cross-sectional.

SETTING

NHIS Sample Child Core questionnaire 2007-2018 data set.

PARTICIPANTS

133 481 children; presence of SCD was determined by an affirmative response from the adult or guardian of the child.

MAIN OUTCOME MEASURES

Multivariate logistic regression was used to compare the associations between SCD status, SES and SDoH for various medical conditions for all races and separately for black children at p<0.05.

RESULTS

133 481 children (mean age 8.5 years, SD: 0.02), 215 had SCD and ~82% (weighted) of the children with SCD are black. Children with SCD were more likely to suffer from comorbid conditions, that is, anaemia (adjusted OR: 27.1, p<0.001). Furthermore, children with SCD had at least two or more emergency room (ER) visits (p<0.001) and were more likely to have seen a doctor 1-15 times per year (p<0.05) compared with children without SCD. Household income (p<0.001) and maternal education were lower for children with SCD compared with children without SCD (52.4% vs 63.5% (p<0.05)). SCD children with a maternal parent who has < / > High School degree were less likely to have no ER visits or 4-5 ER visits, and more likely to have 2-3 ER visits within 12 months.

CONCLUSION

Children with SCD experienced significant comorbid conditions and have high healthcare usage, with black children being disproportionately affected. Moreover, maternal education status and poverty level illustrates how impactful SES can be on healthcare seeking behaviour for the SCD population. SDoH have significant implications for managing paediatric patients with SCD in clinical settings.

Trends in quality of care among children with sickle cell anemia

INTRODUCTION

For decades, it has been recommended that children with sickle cell anemia (SCA) receive antibiotic prophylaxis to prevent serious infections and undergo transcranial Doppler (TCD) screening to identify those at highest risk of overt stroke. We assessed recent temporal trends in antibiotic prophylaxis prescription fills and TCD screening among children with SCA using validated quality measures.

PROCEDURE

Using validated claims-based definitions, we identified children with SCA who were enrolled in Michigan or New York State (NYS) Medicaid programs (2011-2018). Among recommended age groups, two outcomes were assessed yearly: (a) filling of ≥300 days of antibiotics, and (b) receipt of greater than or equal to one TCD. The proportion of children with each outcome was calculated by state. Temporal trends in each preventive service were assessed using generalized linear models.

RESULTS

A total of 1784 children were eligible for antibiotic prophylaxis (Michigan: 384; NYS: 1400), contributing 3322 person-years. Annual rates of filling ≥300 days of antibiotics ranged from 16% to 22% and were similar by state. There was no change in rates of antibiotic filling over time in Michigan (p-value: .10), but there was a decrease in NYS (p-value: .02). A total of 3439 children with SCA were eligible for TCD screening (Michigan: 710; NYS: 2729), contributing 10,012 person-years. Annual rates of TCD screening ranged from 39% to 45%, were similar by state, and did not change over time (p-values >.05).

CONCLUSIONS

Most children with SCA do not receive recommended antibiotic prophylaxis and/or TCD screening. New, sustainable, and coordinated interventions across preventive services are urgently needed.

Administrative data identify sickle cell disease: A critical review of approaches in U.S. health services research

To identify people living with sickle cell disease (SCD) and study their healthcare utilization, researchers can either use clinical records linked to administrative data or use billing diagnosis codes in stand-alone administrative databases. Correct identification of individuals clinically managed for SCD using diagnosis codes in claims databases is limited by the accuracy of billing codes in outpatient encounters. In this critical review, we assess the strengths and limitations of claims-based SCD case-finding algorithms in stand-alone administrative databases that contain both inpatient and outpatient records. Validation studies conducted using clinical records and newborn screening for confirmation of SCD case status have found that algorithms that require three or more nonpharmacy claims or one inpatient claim plus two or more outpatient claims with SCD codes show acceptable accuracy (positive predictive value and sensitivity) in children and adolescents. Future studies might seek to assess the accuracy of case-finding algorithms over the lifespan.

Association between clinical outcomes and metformin use in adults with sickle cell disease and diabetes mellitus

Metformin was recently found to increase fetal hemoglobin, which is protective in sickle cell disease (SCD). We tested the hypothesis that, among adults with SCD and diabetes mellitus (DM), metformin use is associated with fewer adverse SCD clinical outcomes and lower health care utilization. This is a retrospective cohort study using the MarketScan Medicaid claims database for 2006 to 2016, comparing metformin users and nonusers. Patients on hydroxyurea, insulin, or iron chelation were excluded. Main outcomes included annual rates of all-cause inpatient encounters, all-cause emergency department (ED) encounters, inpatient and ED encounters with SCD codes, vaso-occlusive episodes (VOEs), strokes, acute chest syndrome (ACS), avascular necrosis (AVN), and gallstones. Of 457 adults (median age [interquartile range], 43 years [33-52 years]; 72% female), 142 (31%) were treated with metformin. Adjusted for age, sex, and Charlson Comorbidity Index, metformin users had significantly lower rate ratios of all-cause inpatient encounters (0.68; 95% confidence interval [CI], 0.52-0.88; P < .01), inpatient encounters with SCD codes (0.45; 95% CI, 0.30-0.66; P < .01), ED encounters with SCD codes (0.34; 95% CI, 0.21-0.54; P < .01), VOE (0.22; 95% CI, 0.12-0.41; P < .01), ACS (0.17; 95% CI, 0.05-0.60; P = .01), and AVN (0.30; 95% CI, 0.11-0.87; P = .03). A subgroup analysis of 54 enrollees preinitiation and postinitiation of metformin did not indicate significant changes in rates of clinical events. Metformin was associated with significantly fewer inpatient and ED SCD encounters in adults with SCD and DM; however, confounding of underlying SCD severity cannot be excluded.

Hydroxyurea Initiation Among Children With Sickle Cell Anemia

This study assesses characteristics of children with sickle cell anemia associated with hydroxyurea initiation. Medicaid administrative claims from 6 states (2005-2012) were used to identify children with sickle cell anemia enrolled in Medicaid for ≥2 years. Hydroxyurea use was defined as >30 days' supply of filled prescriptions. Children were classified as initiators (no use in year 1; use in year 2) or nonusers (no use in either year). Logistic regression was used to estimate associations between initiation, health care encounters, and demographics. A total of 4435 children were enrolled for 2 years during the study period; 885 (20.0%) initiators and 3080 (69.4%) nonusers. Children had an annual mean of 2.0 sickle cell disease-related inpatient admissions (SD = 2.2), 8.2 sickle cell disease-related outpatient visits (SD = 7.2), and 3.6 emergency department visits (SD = 3.5). The odds of initiating hydroxyurea increased with increasing health care utilization, age, and calendar year (all P values <.05).

Antibiotic Prophylaxis for Children With Sickle Cell Anemia

BACKGROUND

Children with sickle cell anemia (SCA) are at increased risk for invasive pneumococcal disease; antibiotic prophylaxis significantly reduces this risk. We calculated the proportion of children with SCA who received ≥300 days of antibiotic prophylaxis and identified predictors of such receipt.

METHODS

Children aged 3 months to 5 years with SCA were identified by the presence of 3 or more Medicaid claims with a diagnosis of SCA within a calendar year (2005-2012) in Florida, Illinois, Louisiana, Michigan, South Carolina, and Texas. Receipt of antibiotics was identified through claims for filled prescriptions. The outcome, receipt of ≥300 days of antibiotics, was assessed annually by using varying classifications of antibiotics. By using logistic regression with generalized estimating equations, we estimated the odds of receiving ≥300 days of antibiotics, with potential predictors of age, sex, year, state, and health services use.

RESULTS

A total of 2821 children contributed 5014 person-years. Overall, only 18% of children received ≥300 days of antibiotics. Each additional sickle cell disease-related outpatient visit (odds ratio = 1.01, 95% confidence interval: 1.01-1.02) and well-child visit (odds ratio = 1.08, 95% confidence interval: 1.02-1.13) was associated with incrementally increased odds of receiving ≥300 days of antibiotics.

CONCLUSIONS

Despite national recommendations and proven lifesaving benefit, antibiotic prophylaxis rates are low among children with SCA. Numerous health care encounters may offer an opportunity for intervention; in addition, such interventions likely need to include social factors that may affect the ability for a child to receive and adhere to antibiotic prophylaxis.

Rigorous and practical quality indicators in sickle cell disease care

In recent years, several sickle cell-specific quality indicators have been developed using rigorous approaches. A review of the history and current status of the development of sickle cell-specific indicators highlights opportunities for future refinement. Despite efforts at alignment, lack of strong evidence hinders the adoption of current quality indicators across stakeholder groups. There are many directions in which to take the current existing quality indicators, including expanding to different age groups, aims of care such as safety and equity, and better understanding of contextual and environmental factors.

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.

Preventive Care Delivery to Young Children With Sickle Cell Disease

Preventive services can reduce the morbidity of sickle cell disease (SCD) in children but are delivered unreliably. We conducted a retrospective cohort study of children aged 2 to 5 years with SCD, evaluating each child for 14 months and expecting that he/she should receive ≥75% of days covered by antibiotic prophylaxis, ≥1 influenza immunization, and ≥1 transcranial Doppler ultrasound (TCD). We used logistic regression to quantify the relationship between ambulatory generalist and hematologist visits and preventive services delivery. Of 266 children meeting the inclusion criteria, 30% consistently filled prophylactic antibiotic prescriptions. Having ≥2 generalist, non-well child care visits or ≥2 hematologist visits was associated with more reliable antibiotic prophylaxis. Forty-one percent of children received ≥1 influenza immunizations. Children with ≥2 hematologist visits were most likely to be immunized (62% vs. 35% among children without a hematologist visit). Only 25% of children received ≥1 TCD. Children most likely to receive a TCD (42%) were those with ≥2 hematologist visits. One in 20 children received all 3 preventive services. Preventive services delivery to young children with SCD was inconsistent but associated with multiple visits to ambulatory providers. Better connecting children with SCD to hematologists and strengthening preventive care delivery by generalists are both essential.

A validated measure of adherence to antibiotic prophylaxis in children with sickle cell disease

BACKGROUND

Antibiotic prophylaxis is a mainstay in sickle cell disease management. However, adherence is estimated at only 66%. This study aimed to develop and validate a Sickle Cell Antibiotic Adherence Level Evaluation (SCAALE) to promote systematic and detailed adherence evaluation.

METHODS

A 28-item questionnaire was created, covering seven adherence areas. General Adherence Ratings from the parent and one health care provider and medication possession ratios were obtained as validation measures.

RESULTS

Internal consistency was very good to excellent for the total SCAALE (α=0.89) and four of the seven subscales. Correlations between SCAALE scores and validation measures were strong for the total SCAALE and five of the seven subscales.

CONCLUSION

The SCAALE provides a detailed, quantitative, multidimensional, and global measurement of adherence and can promote clinical care and research.

Systematic and Meta-Analytic Review: Medication Adherence Among Pediatric Patients With Sickle Cell Disease

OBJECTIVE

To provide a comprehensive summary (systematic review) of medication adherence rates by assessment method and medication type for pediatric patients with sickle cell disease (SCD), as well as identify important correlates for future research.

METHODS

Articles assessing medication adherence and published between 1982 and February 2015 (n = 49) were identified using electronic databases. A meta-analysis of 14 studies examining demographic, medical, and psychosocial factors and medication adherence was conducted.

RESULTS

Adherence rates ranged from 12% to 100% across all medications. Approximately 30% of studies reported associations between adherence and key demographic, medical, and psychosocial correlates. Mean effect sizes were small to moderate (r = .02-.53).

CONCLUSIONS

The wide range of adherence rates reported in the literature may be because of, in part, the use of variable assessment strategies. Future studies examining pediatric SCD adherence should incorporate key correlates with the goal of replication.

The relationship between a worksite wellness clinic and hospital emergency department visits

OBJECTIVE

To assess the relationship between the provision of episodic medical care at the worksite and nonadmission emergency department (ED) visits.

METHODS

A historical cohort design was used to study the differences of nonadmission ED visits among insurance plan participants employed at two acute care hospitals, one with a worksite wellness clinic and one without over an 8-year period.

RESULTS

A significant reduction in the risk of an insurance plan member visiting the ED in the time period after the clinic was opened among plan members with access to a worksite wellness clinic was observed. No significant reduction was noted in ED visits for insurance plan members without access to a worksite clinic.

CONCLUSIONS

A wellness clinic rendering episodic medical care is associated with significant reductions in ED visits and insured employees who use an ED.

How we prevent and manage infection in sickle cell disease

Sickle cell disease (SCD) affects approximately 100,000 people in the US, 12,500 in the UK, and millions worldwide. SCD is typified by painful vaso-occlusive episodes, haemolytic anaemia and organ damage. A secondary complication is infection, which can be bacterial, fungal or viral. Universal newborn screening, routine use of penicillin prophylaxis, availability of conjugated vaccines against S. pneumoniae and comprehensive care programmes instituted during the past few decades in industrialized countries have dramatically reduced childhood mortality and improved life expectancy. Yet patients with SCD remain at increased risk of infection. Unfortunately, the treatment of most bacterial infections that are common in SCD is not based on the results of randomized controlled clinical trials. In their absence, treatment decisions are based on consensus guidelines, clinical experience or adapting treatment applied in other diseases. This leads to wide variation in treatment among institutions and even between treating physicians in a single institution. Prevention of infection, when possible, is most important and we focus on prevention through targeted prophylaxis and vaccination. We will share our management strategies for managing the more common infections in SCD and provide the rationale for our recommendations.

Transcranial Doppler screening of Medicaid-insured children with sickle cell disease

Transcranial Doppler screening reduces the risk of stroke in children with sickle cell disease. We tested the effect of informational letters sent to parents and doctors of Medicaid-insured children on improving screening efficiency. The letters did not improve the low baseline screening rates, suggesting the need for more aggressive outreach. Hematologist visits were correlated with increased screening rates.

Medication adherence among pediatric patients with sickle cell disease: a systematic review

OBJECTIVES

Describe rates of adherence for sickle cell disease (SCD) medications, identify patient and medication characteristics associated with nonadherence, and determine the effect of nonadherence and moderate adherence (defined as taking 60%-80% of doses) on clinical outcomes.

METHODS

In February 2012 we systematically searched 6 databases for peer-reviewed articles published after 1940. We identified articles evaluating medication adherence among patients <25 years old with SCD. Two authors reviewed each article to determine whether it should be included. Two authors extracted data, including medication studied, adherence measures used, rates of adherence, and barriers to adherence.

RESULTS

Of 24 articles in the final review, 23 focused on 1 medication type: antibiotic prophylaxis (13 articles), iron chelation (5 articles), or hydroxyurea (5 articles). Adherence rates ranged from 16% to 89%; most reported moderate adherence. Medication factors contributed to adherence. For example, prophylactic antibiotic adherence was better with intramuscular than oral administration. Barriers included fear of side effects, incorrect dosing, and forgetting. Nonadherence was associated with more vaso-occlusive crises and hospitalizations. The limited data available on moderate adherence to iron chelation and hydroxyurea indicates some clinical benefit.

CONCLUSIONS

Moderate adherence is typical among pediatric patients with SCD. Multicomponent interventions are needed to optimally deliver life-changing medications to these children and should include routine monitoring of adherence, support to prevent mistakes, and education to improve understanding of medication risks and benefits.

Identifying sickle cell disease cases using administrative claims

OBJECTIVE

To develop and test the accuracy of administrative claims method for identifying children with sickle cell disease (SCD) to enable quality of care assessments among children enrolled in Medicaid.

METHODS

All administrative claims with an SCD diagnosis were obtained from Michigan Medicaid from 2008 to 2011 for children ≤18 years, representing 1828 individuals. All Medicaid claims were obtained for these children and classified into categories on the basis of SCD care; these classifications were used to develop 37 alternative case definitions for identifying children with SCD. Children with ≥1 SCD claim in 2010 or 2011 were identified as confirmed SCD or not SCD using the gold standard of Michigan newborn screening administrative records. Measures of performance were calculated for each case definition for eligible children in 2010. Further validation of the case definitions was performed among eligible children in 2011.

RESULTS

In 2010, a total of 938 children met eligibility criteria and were linked to newborn screening records; 605 (59%) were confirmed SCD, and 333 (32%) were not SCD. Measures of performance varied among the 37 case definitions, and the 4 best case definitions on the basis of the sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve were validated among 924 children meeting eligibility criteria in 2011. The case definition of at least 3 SCD claims in any position identified children with SCD with the most accuracy, with an area under the ROC curve of 0.91 (95% confidence interval 0.89, 0.93).

CONCLUSIONS

This definition can be used to facilitate a more accurate identification of children with SCD in future studies. Further investigation is necessary to determine whether this method translates to other populations besides Michigan Medicaid-insured children.

Burden of illness of patients with allergic asthma versus non-allergic asthma

OBJECTIVE

Allergic and non-allergic asthma share similar symptoms, but differ in that allergic asthma is triggered by inhaled allergens. This study compared healthcare resource utilization (HCRU) and costs between these groups using US employer-based claims data.

METHODS

Health insurance claims from Truven Marketscan database (2002Q1-2010Q2) were analyzed. Included patients had ≥2 asthma diagnoses and ≥1 year of eligibility prior to and following the date of first asthma diagnosis. Patients with ≥1 diagnosis for allergic asthma and ≥1 diagnosis for other allergic conditions formed the allergic asthma cohort whereas patients without any of these diagnoses formed the non-allergic asthma cohort. Allergic and non-allergic asthma patients were matched 1:1. HCRU and costs during the study period were compared between cohorts using incidence rate ratios (IRR) and bootstrap methods.

RESULTS

Sixty four thousand four hundred and seventy three allergic and non-allergic asthma patients were matched (mean age = 30; 57.1% female; mean CCI = 0.2), with 7.1% and 0.36% having received an allergy test during the baseline period, respectively. During the study period, allergic asthma patients had significantly more asthma-related pharmacy dispensings (IRR[95% CI] = 2.25[2.22-2.28], p < 0.001) and asthma-related outpatient visits (IRR[95% CI] = 2.29[2.27-2.32], p < 0.001). Allergic asthma patients incurred 39% greater per-patient-per-year all-cause costs (allergic: $4008; non-allergic: $2889, p < 0.001) and 79% greater asthma-related costs (allergic: $1063; non-allergic: $592, p < 0.001) than non-allergic asthma patients.

CONCLUSIONS

These results indicate, even in a relatively healthy population, allergic asthma is associated with greater HCRU and costs. Guideline-recommended IgE allergy tests should be employed in distinguishing the two forms of asthma, to optimize patient management and reduce costs.

Bacteremia risk and outpatient management of febrile patients with sickle cell disease

BACKGROUND AND OBJECTIVES

Previous studies have indicated that febrile children with sickle cell disease (SCD) had a 3% to 5% risk of being bacteremic due to compromised immune function. The introduction of routine penicillin prophylaxis and conjugate vaccines may have lowered the risk of bacteremia. Our goals were to determine the rate of bacteremia among children with SCD per febrile episode and to estimate the safety of outpatient management among these febrile SCD patients.

METHODS

This 18-year retrospective cohort study included febrile SCD patients who presented to Boston Children's Hospital between 1993 and 2010.

RESULTS

A total of 1118 febrile episodes were evaluated. Nine blood specimens had growth of a pathogen in culture (0.8%; 95% confidence interval: 0.3%-1.3%). Of the 466 febrile patients initially managed as outpatients, 3 were bacteremic (0.6%). All 3 received intravenous ceftriaxone at the initial outpatient visit and returned when contacted after growth of bacteria was detected in the blood culture. Upon return to the hospital, none were "ill appearing," required supportive care, or were admitted to an ICU.

CONCLUSIONS

Our rate of bacteremia among febrile children with SCD is much lower than previous estimates, and there was no associated morbidity or mortality among the patients managed as outpatients. A well-appearing febrile child with SCD may be managed as an outpatient after blood is obtained for bacterial culture and parenteral antibiotics are administered, provided there are no other reasons for admission and the patient is able to return promptly for worsening condition or for growth of a pathogen from their blood culture.

Adherence to transcranial Doppler screening guidelines among children with sickle cell disease

BACKGROUND

Little is known about adherence to guidelines recommending yearly screening with transcranial Doppler (TCD) ultrasonography to detect stroke risk for children with severe sickle cell disease. The objective was to determine the proportion of children with hemoglobin SS (HbSS) or sickle-β(0) -thalassemia (HbSβ(0) ) aged 2-16 years who received recommended TCD screening from 1997 to 2008, and to identify factors associated with adherence.

PROCEDURE

A retrospective cohort study included patients enrolled in Tennessee Medicaid with HbSS or HbSβ(0) who received care at the two largest sickle cell centers in Tennessee. The outcome of interest was adherence with guidelines for annual screening TCD's, identified from computer claims and validated through medical record review. The cumulative rate of children who received a TCD per year was calculated using the Kaplan-Meier method. Cox proportional hazards regression was used to examine the association of child, family, and health care use characteristics with receiving a TCD.

RESULTS

Among 338 TCD eligible at-risk children, 232 (68.6%) had at least one TCD during the study period. The yearly cumulative incidence of annual TCD's increased from 2.5% in 1997 to 68.3% in 2008. In multivariate models, calendar year, maternal education, and increased number of sickle cell related outpatient visits were associated with an increased rate of receiving a TCD.

CONCLUSIONS

Publicly insured children with HbSS or HbSβ(0) had increasing adherence with TCD screening guidelines between 1997 and 2008, though 31% had no TCD at all during follow-up. Increasing number of sickle cell related outpatient visits was associated with increasing adherence to screening guidelines.

Setting the agenda for quality improvement in pediatric sickle cell disease

OBJECTIVE

Despite recent scientific advances, children with sickle cell disease (SCD) continue to experience high mortality and significant morbidity, in part due to variations in the care provided. We sought to identify and compare drivers for quality improvement among clinical staff and parents of children with SCD.

METHODS

We interviewed clinical staff across care settings in an urban teaching hospital to elicit their perspectives on improving care for children with SCD. Concurrently, we invited parents of children with SCD to participate in focus groups to identify their needs. Findings are reported according to Consolidated Criteria for Reporting Qualitative Research guidelines.

RESULTS

We conducted 29 interviews with clinical staff and 4 focus groups with parents. Both groups identified the need for effective communication of relevant patient information across disciplines as a key area for improvement. Clinical staff cited standardization of care delivery as a top priority through increased accessibility of pertinent clinical information, enhanced pain assessment and management, and improved availability of clinical decision-making tools. Parents listed the need for increased community awareness about SCD, including school and day care staff, enhanced parental education and peer support, and self-management skills for their children as opportunities to improve pediatric SCD care.

CONCLUSIONS

Identifying drivers for quality improvement is a critical first step in transforming the care provided to children with SCD. Using a systematic approach that includes eliciting the perspectives of both clinicians and parents may significantly enhance the development of a patient-centered quality improvement agenda.

Ambulatory care connections of Medicaid-insured children with sickle cell disease

BACKGROUND

Sickle cell disease (SCD) requires coordinated ambulatory care from generalists and hematologists. We examined when children with SCD establish ambulatory care connections, whether these connections are maintained, and how these connections are used before and after hospitalizations.

PROCEDURE

We conducted a retrospective cohort study of Medicaid-insured Maryland children with SCD from 2002 to 2008. For children enrolled from birth, time to first, second, and third generalist and first hematologist visits was plotted. For all children, we analyzed ambulatory visits by age group, by emergency department (ED) and hospital use, and before and after hospitalizations.

RESULTS

The overall study cohort comprised 851 children; 178 provided data from birth. Ambulatory care connections to generalists were made rapidly; connections to hematologists occurred more slowly, if at all (38% of children had not seen a hematologist by age 2 years). Visits with generalists decreased as patients aged, as did visits with hematologists (54% of children in the 12-17 year age group had no hematology visits in 2 years). Children with higher numbers of ED visits or hospitalizations also had higher numbers of ambulatory visits (generalist and hematologist). Most children had visits with neither generalists nor hematologists in the 30 days before and after hospitalizations.

CONCLUSIONS

Medicaid-insured children with SCD rapidly connect with generalists after birth; connections to hematologists occur more slowly. The observation that connections to generalists and hematologists diminish with time and are infrequently used around hospitalizations suggests that the ambulatory care of many Medicaid-insured children with SCD may be inadequate.

Hospitalization for invasive pneumococcal disease in a national sample of children with sickle cell disease before and after PCV7 licensure

OBJECTIVE

To estimate national hospitalization rates for invasive pneumococcal disease (IPD) in children with sickle cell disease (SCD) before and after the 2000 licensure of the heptavalent pneumococcal conjugate vaccine (PCV7).

PROCEDURE

We performed a retrospective trend analysis of the 1994-2007 Nationwide Inpatient Sample databases. Hospitalizations involving children with SCD and IPD were identified by ICD-9CM code. The primary outcomes, the annual hospitalization rate for IPD in children with SCD and the proportion of hospitalizations for IPD per 100 total SCD hospitalizations, were analyzed using multivariable linear regression and contingency analysis, respectively.

RESULTS

A total of 1,242 hospitalizations for IPD in SCD patients were identified from 1994-2007, with a mortality rate of 2.4%. The national mean annual rate of IPD hospitalization decreased by 65%, from 131.8  cases/year from 1994 to 2000 to 45.5  cases/year from 2001 to 2007 (P = 0.001). The national proportion of hospitalizations for IPD per 100 total SCD hospitalizations decreased from 0.4 to 0.15 (P < 0.0001) over the same interval. Following PCV7 licensure, the mean annual cumulative hospital days and cumulative hospital charges decreased nationally by 53% and 36%, respectively.

CONCLUSION

In a national sample, PCV7 licensure is temporally associated with a nearly threefold reduction in IPD hospitalizations in children with SCD.

Outpatient follow-up and rehospitalizations for sickle cell disease patients

BACKGROUND

Rehospitalization rates are increasingly used as quality indicators for a variety of illnesses, including sickle cell disease. While one small, single center study suggested outpatient follow-up with a pediatric hematologist was associated with fewer rehospitalizations, no study has examined the effect of post-discharge outpatient follow-up on rehospitalization rates across ages and beyond a single site.

PROCEDURE

This is a retrospective cohort study using Wisconsin Medicaid claims data for hospitalized children and adults with sickle cell disease from 2003 to 2007. The primary outcomes were rehospitalization at both 14 and 30 days after an index hospitalization for sickle cell pain crisis (ICD-9-CM codes 28242, 28262, 28264, 28269). Univariate survival analyses were performed based on outpatient visit, severe disease, asthma, and age. The Cox proportional hazards model was used for multivariate analyses yielding hazard ratios for the association between outpatient visits and subsequent rehospitalization rates.

RESULTS

Of the 408 patients included, 42 (10.2%) patients were rehospitalized within 14 days and 70 (17.1%) were rehospitalized within 30 days. Multivariate analysis showed that an outpatient visit is associated with lower rates of both 30-day rehospitalization (Hazard Ratio (HR) 0.442; 95%CI: 0.330-0.593) and 14-day rehospitalization (HR 0.226; 95%CI: 0.124-0.412), with the majority of 30-day rehospitalizations occurring within 14 days.

CONCLUSIONS

For sickle cell disease, post-discharge planning should emphasize early follow-up to prevent subsequent hospitalization and improve care quality. Pediatr Blood Cancer 2012; 58: 406-409. © 2011 Wiley Periodicals, Inc.

Carriage of encapsulated bacteria in Gabonese children with sickle cell anaemia

Sickle cell anaemia (SCA) is a haemoglobin disorder that alters the deformability of erythrocytes through abnormal polymerization of haemoglobin. Children with SCA have an increased risk of infections with encapsulated bacteria. To guide the antibiotic prophylaxis and vaccinations in children with SCA in Gabon, we characterized Streptococcus pneumoniae, Staphylococcus aureus and Haemophilus influenzae from children with and without SCA. We performed a cross-sectional study and compared nasal and pharyngeal S. pneumoniae, Staph. aureus and H. influenzae isolates from SCA children (n = 73) with comparators matched for age, residence and sex (n = 143) in a matched-comparison analysis. The resistance pattern and capsular type were identified for each isolate. The total carriage rate for S. pneumoniae, Staph. aureus and H. influenzae was 13.8%, 46.7% and 12.5%, respectively, and did not differ between groups (p >0.05). The mean number of days under antibiotic treatment in the past year was higher in children with SCA than in controls (penicillin: 70.1 vs 0.1 days, p 0.00002). The total non-susceptibility rate was 30% for oral and parenteral (meningitis) penicillin in S. pneumoniae, resistance rates were 1.6% for oxacillin in Staph. aureus and 14.8% for ampicillin in H. influenzae. Susceptibility to antibiotic agents and distribution of capsular types did not differ significantly between both groups. In conclusion, carriage and resistance rates are similar in children with and without SCA. Our data provide the basis to guide empiric therapy of invasive diseases caused by S. pneumoniae, Staph. aureus and H. influenza in children in Gabon.

Sickle cell disease in California: sociodemographic predictors of emergency department utilization

BACKGROUND

Patients with sickle cell disease (SCD) visit emergency departments (EDs) in rates leading to a significant health system burden. However, limited comprehensive evaluations of utilization patterns have been published using data connecting visits to patients across facilities. This study aims to examine sociodemographic predictors of ED utilization in SCD.

PROCEDURE

This retrospective cohort study employed 2007 data from the California Office of Statewide Health Planning and Development (OSHPD). Data included all ED encounters from California hospitals; identifiers connected each visit to an individual patient, across all facilities in the state. Multivariate regression techniques evaluated sociodemographic predictors of utilization while adjusting for confounding variables.

RESULTS

In 2007, 2,920 California patients with SCD made 16,364 ED visits. Adults ≥ 21 years of age had higher ED visit rates than children and were more likely to both be in the highest tier of users and visit multiple facilities. Patients living further from a self-identified provider of comprehensive SCD care had higher rates of ED visits and a lower likelihood of hospitalization from the ED. Publicly insured patients had higher rates of ED visits and were more likely to be in the highest tier of users than were the privately insured or uninsured.

CONCLUSIONS

Adulthood ≥ 21 years of age, distance from comprehensive SCD care, and insurance status are significant predictors of ED utilization in SCD. As a routine source of care decreases ED utilization, these findings prompt concern that these factors act as barriers to accessing comprehensive SCD care.

Bacteremia in children with sickle hemoglobinopathies

BACKGROUND

Bacteremia is one of the most feared infectious complications of sickle cell disease, and it is associated with a high mortality rate in children. The objective of our study was to investigate the proportion of bacteremia among febrile children with sickle hemoglobinopathies and the clinical factors associated with bacteremia.

METHODS

Clinical and microbiological data from children with sickle hemoglobinopathies being followed up at the Pediatric Hematology Clinic at the University of Rochester Medical Center in Rochester, New York, were retrospectively analyzed. The data were collected from medical records covering the time period of June 1997 to December 2006, which included the periods before and after the introduction of routine heptavalent pneumococcal conjugate vaccine usage. Proportions of positive blood cultures among febrile children, the types of organisms causing bacteremia, and clinical and sociodemographic factors were analyzed by χ and t tests as appropriate.

RESULTS

The overall proportion of positive blood cultures was 3.8%; 1% was considered to yield true pathogens. Pneumococcal bacteremia decreased from 0.7% in the pre-pneumococcal conjugate vaccine-7 era to 0.2% in the post-pneumococcal conjugate vaccine-7 era; however, the difference was not statistically significant. Pathogens other than pneumococcus were responsible for most bacteremic episodes. No clinical or social factors were found to have statistically significant associations with positive blood cultures.

CONCLUSIONS

Approximately 1% of children with sickle hemoglobinopathies with fever have bacteremia despite current penicillin prophylaxis and pneumococcal immunization, although most episodes are due to nonpneumococcal pathogens. Prompt evaluation of such febrile children with sickle hemoglobinopathies remains warranted.

Sickle-cell disease in California: a population-based description of emergency department utilization

BACKGROUND

Acute and chronic clinical manifestations of sickle-cell disease (SCD) lead to significant healthcare utilization, especially of the emergency department (ED). Limited population-level data are available in SCD with the ability to connect patients to visits, leaving us with minimal description of utilization patterns.

PROCEDURE

Using ED discharge data with links between patients and visits, we sought to describe the California SCD population and its ED utilization patterns across facilities. Non-public California Office of Statewide Health Planning and Development data employ unique patient identifiers, linking patients, and visits.

RESULTS

SCD patients of all ages are heavily reliant on Medicaid (46%). The majority of SCD Californians visit an ED more than once during a year (69%), but only a minority use more than one facility during a year (34%). However, adults with SCD have multiple visits and utilize multiple EDs in higher proportions than do children (72% vs. 60% and 40% vs. 21%, respectively). A higher proportion of visits to the ED are made by SCD adults, but a higher proportion of visits by children result in hospital admission. Uninsured adults outnumber uninsured children (16% vs. 5%).

CONCLUSIONS

ED utilization by the California SCD population is described on a population level. Utilization patterns by adults point towards increased utilization in the population no longer eligible for Title V pediatric coverage for their disease. Further investigation using population-level socioeconomic and geographic correlates is warranted to evaluate the factors leading to ED utilization in SCD.

Administrative data sets and health services research on hemoglobinopathies: a review of the literature

CONTEXT

Large administrative healthcare data sets are an important source of data for health services research on sickle cell disease (SCD) and thalassemia. This paper identifies and describes major U.S. healthcare administrative databases and their use in published health services research on hemoglobinopathies.

EVIDENCE ACQUISITION

Publications that used U.S. administrative healthcare data sets to assess healthcare use or expenditures were identified through PubMed searches using key words for SCD and either costs, expenditures, or hospital discharges; no additional articles were identified by using thalassemia as a key word. Additional articles were identified through manual searches of related articles or reference lists.

EVIDENCE SYNTHESIS

A total of 26 original health services research articles were identified. The types of administrative data used for health services research on hemoglobinopathies included federal- and state-specific hospital discharge data sets and public and private health insurance claims databases. Gaps in recent health services research on hemoglobin disorders included a paucity of research related to thalassemia, few studies of adults with hemoglobinopathies, and few studies focusing on emergency department or outpatient clinic use.

CONCLUSIONS

Administrative data sets provide a unique means to study healthcare use among people with SCD or thalassemia because of the ability to examine large sample sizes at fairly low cost, resulting in greater generalizability than is the case with clinic-based data. Limitations of administrative data in general include potential misclassification, under-reporting, and lack of sociodemographic information.

Discontinuation of thyroid hormone treatment among children in the United States with congenital hypothyroidism: findings from health insurance claims data

BACKGROUND

Thyroid hormone treatment in children with congenital hypothyroidism can prevent intellectual disability. Guidelines recommend that children diagnosed with congenital hypothyroidism through newborn screening remain on treatment to at least 3 years of age, after which a trial off therapy can determine which children have transient hypothyroidism. The purpose of this study was to describe the rate at which children with congenital hypothyroidism in the United States discontinue thyroid hormone treatment in early childhood.

METHODS

Retrospective analysis of the 2002-2006 MarketScan(R) Commercial Claims and Encounters research databases and the 2001-2005 MarketScan Multi-State Medicaid databases. Children were classified as having congenital hypothyroidism based on billing codes and having filled a prescription for thyroid hormone treatment. Kaplan-Meier curve analysis was used to determine discontinuation rates.

RESULTS

There were a total of 412 Medicaid-enrolled children and 292 privately-insured children with presumed congenital hypothyroidism included in this study. The overall birth prevalence of congenital hypothyroidism across both datasets was about 1 per 2,300. By 36 months, the percentage who had discontinued thyroid replacement treatment was 38% (95% Confidence Interval: 32%-44%). Medicaid-enrolled children had a more rapid decline in the first 24 months of treatment compared to those with private insurance (P = 0.02).

CONCLUSIONS

More than one-third of children treated for congenital hypothyroidism discontinued treatment within 36 months, which is inconsistent with current guidelines. It is not known how many of these children required continued treatment or experience adverse effects from discontinuation. These findings emphasize the critical need for follow-up systems to monitor the outcome of newborn screening.

Burden of influenza-related hospitalizations among children with sickle cell disease

OBJECTIVE

Children with sickle cell disease (SCD) are considered to be at high risk for complications from influenza infection despite minimal published data that characterize the burden of influenza in this population. Our objectives were to (1) estimate the rate of influenza-related hospitalizations (IRHs) among children with SCD, (2) compare this rate with rates of children with cystic fibrosis (CF) and children with neither SCD nor CF, and (3) explore mechanisms that underlie these potentially preventable hospitalizations.

METHODS

We analyzed hospitalizations from 4 states (California, Florida, Maryland, and New York) across 2 influenza seasons (2003-2004 and 2004-2005) from the Healthcare Cost and Utilization Project State Inpatient Databases. We included hospitalizations with a discharge diagnosis code for influenza in a child <18 years of age. We used census data and disease prevalence estimates to calculate denominators and compare rates of IRH among children with SCD, CF, and neither disease.

RESULTS

There were 7896 pediatric IRHs during the 2 influenza seasons. Of these, 159 (2.0%) included a co-occurring diagnosis of SCD. Annual rates of IRHs were 112 and 2.0 per 10 000 children with and without SCD, respectively, across both seasons. Children with SCD were hospitalized with influenza at 56 times (95% confidence interval: 48-65) the rate of children without SCD. Children with SCD had approximately double the risk of IRH compared with children with CF (risk ratio: 2.1 [95% confidence interval: 1.5-2.9]). IRHs among children with SCD were not longer, more costly, or more severe than IRHs among children without SCD; they were also rarely nosocomial and co-occurred with a diagnosis of asthma in 14% of cases.

CONCLUSIONS

IRHs are substantially more common among children with SCD than among those without the disease, which supports the potential importance of vigorous influenza vaccination efforts that target children with SCD.

Healthcare expenditures for privately insured people with cystic fibrosis

With improved survival and new therapies for people with cystic fibrosis (CF), updated information on medical care expenditures for those individuals is needed. We estimated medical care expenditures, including both insurance reimbursements and patient out-of-pocket expenses, for privately insured people with CF and investigated how those expenditures varied with certain complications of CF. From a private insurance claims database of people covered by health plans associated with large corporate employers, we identified people with CF who were currently receiving medical care for the disorder and characterized their medical expenditures during the period 2004-2006. We selected a matching group of people who did not have CF based on age, sex, and geographic area, and calculated incremental expenditures associated with CF. We also examined the effect of age and certain complications of CF on these expenditures. The annual medical care expenditure for a person with actively managed CF averaged $48,098 in 2006 dollars, which was 22 times higher than for a person without CF. This ratio is high relative to other chronic disorders. Outpatient prescription medications made up the largest component of total expenditures for people with CF (39%). Those who were recorded in claims data as having a liver or lung transplant, malnutrition, diabetes, or a chronic Pseudomonas aeruginosa pulmonary infection incurred much higher expenditures than people without these conditions. People with CF will incur high medical expenditures throughout their lifespan. These findings will assist in the development of economic evaluations of future CF screening and management initiatives.

Health care utilization and expenditures for privately and publicly insured children with sickle cell disease in the United States

BACKGROUND

There are no current national estimates on health care utilization and expenditures for US children with sickle cell disease (SCD).

PROCEDURE

We used the MarketScan Medicaid Database and the MarketScan Commercial Claims and Encounters Database for 2005 to estimate health services use and expenditures. The final samples consisted of 2,428 Medicaid-enrolled and 621 privately insured children with SCD.

RESULTS

The percentage of children with SCD enrolled in Medicaid with an inpatient admission was higher compared to those privately insured (43% vs. 38%), yet mean expenditures per admission were 35% lower ($6,469 vs. $10,013). The mean number of emergency department (ED) visits was 49% higher for Medicaid-enrolled children compared to those with private insurance (1.36 vs. 0.91), but mean expenditures per ED visit were 28% lower. The mean number of non-ED outpatient visits was similar (12.6 vs. 11.5) but mean expenditures were 40% lower for the Medicaid-enrolled children ($3,557 vs. $5,908). The mean expenditures on drug claims were higher among those with Medicaid than private insurance ($1,049 vs. $531). Mean total expenditures for children with SCD enrolled in Medicaid were 25% lower than for privately insured children ($11,075 vs. $14,722). The samples were comparable with respect to SCD-related inpatient discharge diagnoses and use of outpatient blood transfusions.

CONCLUSIONS

Children with SCD enrolled in Medicaid had lower expenditures than privately insured children, despite higher utilization of medical care, which indicates lower average reimbursements. Research is needed to assess the quality of care delivered to Medicaid-enrolled children with SCD and its relation to health outcomes.

Health plan notification and feedback to providers is associated with increased filling of preventer medications for children with asthma enrolled in Medicaid

OBJECTIVE

To test the hypothesis that children enrolled in Medicaid managed care health plans that provide asthma-specific communication to providers would be more likely to have adequate asthma medication filling.

STUDY DESIGN

We conducted a historical cohort study of 4498 children (2-17 years old) with moderate-severe asthma in Washington State and Tennessee Medicaid managed care programs from 2000 to 2002. Interviews with health plans were conducted to identify communication strategies health plans used to improve asthma care by providers in the plan. The main outcome measure was guideline-recommended filling of asthma preventer medications.

RESULTS

Children in plans that provided specific feedback to providers about asthma quality and notified providers when children had an asthma-related event had the highest mean days plus or minus SE of filling in the 365-day follow-up period (164.6 +/- 13 days) compared with children in plans with neither (135.3 +/- 10.8 days; P < .05). In children with the greatest asthma severity, enrollment in a plan with both features was associated with 27.1 additional days of filling (95% CI, 0.7-53.4 days) during the follow-up period.

CONCLUSION

Health plan communication to providers was associated with increased preventer filling in children with moderate-severe asthma in 2 state Medicaid programs.

Effectiveness of the 7-valent pneumococcal conjugate vaccine in children with sickle cell disease in the first decade of life

BACKGROUND

The incidence of and mortality from invasive pneumococcal disease are significantly higher in children with sickle cell disease than in the general pediatric population. The objective of this population-based study was to assess the effect of pneumococcal conjugate vaccine on rates of invasive pneumococcal disease among children with sickle cell disease.

PATIENTS AND METHODS

Records, including the history of pneumococcal conjugate vaccine administration, of 1247 children born after 1983 residing in metropolitan Atlanta, Georgia, with confirmed hemoglobinopathies were linked to an active surveillance database for invasive pneumococcal disease for the period of January 1, 1995, through January 1, 2003. The incidence of invasive pneumococcal disease and the percentage of rate reduction were estimated before and after pneumococcal conjugate vaccine licensure. Survival analysis was used to estimate the effect of pneumococcal conjugate vaccine on invasive pneumococcal disease rates while accounting for herd immunity.

RESULTS

A significant decline in invasive pneumococcal disease in children with sickle cell disease < or = 10 years of age was noted after pneumococcal conjugate vaccine licensure, from 1.7 infections per 100 person-years (1995-2000) to 0.5 infections per 100 person-years (2001-2002), which represents a 68% reduction. The effectiveness of > or = 1 dose of pneumococcal conjugate vaccine was estimated by crude analysis to be 84.5% and by stratified survival analysis to be 81.4% when controlling for the presence of herd immunity in the 2 years after pneumococcal conjugate vaccine licensure. Serotype 6A invasive pneumococcal disease represented 36% of invasive pneumococcal disease before pneumococcal conjugate vaccine licensure and 0% after pneumococcal conjugate vaccine licensure, suggesting a protective effect against this pneumococcal conjugate vaccine-related serotype.

CONCLUSIONS

Invasive pneumococcal disease significantly decreased in children with sickle cell disease < or = 10 years of age after pneumococcal conjugate vaccine licensure. Pneumococcal conjugate vaccine was effective even when controlling for herd immunity. Extending guideline recommendations for catch-up vaccination beyond 4 years of age should be considered.

Impact of proximity to comprehensive sickle cell center on utilization of healthcare services among children with sickle cell disease

BACKGROUND

The impact of comprehensive care on utilization of healthcare services by children with sickle cell disease (SCD) has not been fully evaluated. We compared the medical care utilization and mortality in children less than 20 years of age with SCD in four regions in the state of Tennessee with and without a comprehensive sickle cell center (CSCC).

METHODS

Rates of hospitalizations, outpatient and emergency department (ED) visits, and deaths were measured in a cohort of children aged <20 years with SCD, enrolled in TennCare, from January 1995 to December 2002. TennCare data linked to Tennessee vital records were used to define the population and identify the outcomes. The patients were classified into one of four regions based on their residential address on the day of their hospitalization or outpatient visit.

RESULTS

The cohort consisted of 1,214 children with 6,393 person-years of follow-up. Fifty-six percent of patients resided in the region with the CSCC. This region had the highest overall rates of hospitalization for all children (P < 0.001), while ED and outpatient visits were higher in other areas. The death rates ranged from 1.8 to 4.3 per 1,000 person-years in the four regions and did not represent statistically significant differences.

CONCLUSION

No clear pattern of improved utilization of medical care services were identified in relation to proximity of residence to a CSCC. This cohort was not large enough to detect small differences in death rates. In addition, other outcomes that incorporate quality of life measures may be more sensitive to differences in medical care.

Incidence of Invasive Pneumococcal Disease among Individuals with Sickle Cell Disease before and after the Introduction of the Pneumococcal Conjugate Vaccine

BACKGROUND

We sought to determine the incidence of invasive pneumococcal disease (IPD) among individuals with sickle cell disease (SCD) before and after the introduction of the pneumococcal conjugate vaccine (PCV).

METHODS

Individuals with SCD who were enrolled in Tennessee Medicaid from January 1995 through December 2004 were identified using SCD-specific International Classification of Diseases, Ninth Revision, Clinical Modification codes. Population-based surveillance data were used to identify individuals with IPD and were linked to patients with SCD in the Tennessee Medicaid database to determine incidence rates of IPD. Clinical data were collected on all subjects with IPD, and antibiotic susceptibility testing and serotyping were performed on all available pneumococcal isolates.

RESULTS

We identified 2026 individuals with SCD, who constituted 13,687 person-years of follow-up. During the study period, 37 individuals with SCD developed IPD, and 21 of these patients were aged <5 years. In a comparison of the pre-PCV period (1995-1999) with the post-PCV period (2001-2004), the rate of IPD decreased by 90.8% in children aged <2 years (from 3630 to 335 cases per 100,000 person-years; P<.001) and by 93.4% in children aged <5 years (from 2044 to 134 cases per 100,000 person-years; P<.001). Rates of IPD for patients with SCD who were aged >or=5 years decreased from 161 cases per 100,000 person-years during the pre-PCV period to 99 cases per 100,000 person-years during the post-PCV period (P=.36).

CONCLUSION

The rate of IPD among children with SCD who are aged <5 years has decreased markedly since the introduction of routine administration of PCV to young children.

Sickle cell disease: a question of equity and quality

Thirty years ago, the first major federal legislation concerning sickle cell disease treatment was passed, resulting in the development of comprehensive sickle cell centers. We are now at another watershed moment in the treatment of this illness with the passage in October 2004 of the Sickle Cell Treatment Act, designed to substantially expand specialized sickle cell treatment programs. This legislation offers a remarkable opportunity to significantly improve health outcomes for individuals with sickle cell disease if it is implemented with a specific focus on the distinct but related issues of equity and quality. Despite major advances in sickle cell disease treatment that have occurred over the past 3 decades, important gaps exist both in the equity of government and private philanthropic support for research and in the uniform provision of high quality clinical care. This article assesses the current gaps in funding support and in the implementation of improvements in clinical care in order to suggest strategies for making optimal use of the opportunity that the new legislation presents to improve the health of all individuals affected by this disease.

Controlling invasive pneumococcal disease: is vaccination of at-risk groups sufficient?

Risk factors for invasive pneumococcal disease (IPD) include young and old age, comorbidities (such as splenic dysfunction, immunodeficiencies, chronic renal disease, chronic heart or lung disease or cerebral spinal fluid leak), crowded environments or poor socioeconomic conditions. Universal use of the 7-valent pneumococcal conjugate (7vPncCRM) vaccine for infants and young children has led to significant decreases in IPD in the vaccinated population (direct protection), and there has also been a decrease in the incidence of IPD among the nonvaccinated population (indirect immunity; herd protection). While 7vPncCRM vaccine is administered universally to children in USA, many countries of the European Union have chosen to target children with comorbidities. This review aims to highlight individual risk factors for IPD, describe studies that evaluated pneumococcal conjugate vaccines in at-risk groups and estimate the proportion of at-risk children who may have been vaccinated in the European Union since the 7vPncCRM vaccine was introduced, using UK as an example. Although immunisation targeting only children with comorbidities may achieve satisfactory results for a few, many otherwise healthy children at risk simply because of their age will be neglected, and herd protection might not be established.

Medical care utilization and mortality in sickle cell disease: a population-based study

The purpose of this study was to evaluate the pattern of medical care utilization and mortality in children and adults with sickle cell disease (SCD) in the state of Tennessee. Rates of hospitalization, emergency department visits, and deaths were measured in a cohort of adults and children with SCD enrolled in TennCare, Tennessee's Medicaid managed health care program, from January 1995 to December 2002. TennCare data linked to Tennessee vital records were used to define the population and identify the outcomes. For children less than 5 years of age, the mortality rate was similar to that of other black Tennessee children (P = 0.71). Among children, the death rate was highest in 10-19 years of age and was 8-fold higher than Tennessee's race- and age-specific rate. Among 20- to 49-year-old patients with SCD, mortality was significantly higher in males than in females (P < 0.001). As compared to the black population without SCD in TennCare, patients with SCD had 7-30 times higher rate of hospitalization and 2-6 times higher rates of emergency department visits (P < 0.001). The death rate in adolescents and young adults with SCD continues to be much higher than population-specific rates. Interventions to prevent morbidity and mortality related to SCD are urgently needed.

Research for newborn screening: developing a national framework

Newborn metabolic screening represents the largest application of genetic testing in medicine. As new technologies are developed, the number of conditions amenable to newborn screening (NBS) will continue to expand. Despite the scope of these programs, the evidence base for a number of NBS applications remains relatively weak. This article briefly reviews the evidence base for several conditions. The article then develops a proposal for a structured sequence of research protocols to evaluate potential applications for NBS before their formal implementation in public health programs. Such a framework for research will require collaboration between states and the federal government, a collaboration that is emerging through recent federal legislation and funding.

Pneumococcal conjugate vaccines for preventing vaccine-type invasive pneumococcal disease and pneumonia with consolidation on x-ray in children under two years of age

BACKGROUND

Pneumonia, most commonly caused by Streptococcus pneumoniae (Pnc), is a major cause of morbidity and mortality among young children especially in developing countries. Recently, the prevalence of antibiotic-resistant Pnc has increased worldwide such that the effectiveness of preventive strategies, like the new pneumococcal conjugate vaccines (PCV) on rates of invasive pneumococcal disease (IPD) and pneumonia, needs to be evaluated.

OBJECTIVES

To determine the efficacy of PCV in reducing the incidence of IPD due to vaccine serotypes (VT) and x-ray confirmed pneumonia with consolidation of unspecified etiology in children who received PCV before 12 months of age.

SEARCH STRATEGY

We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 1 2004), MEDLINE (1990 to March 2004) and EMBASE (1990 to December 2003). Reference list of articles, and books of abstracts of relevant symposia, were hand searched. Researchers in the field were also contacted.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing PCV with placebo, or another vaccine, among children below two years with IPD and clinical/radiographic pneumonia as outcomes.

DATA COLLECTION AND ANALYSIS

Two reviewers independently identified eligible studies, assessed trial quality, and extracted data. Differences were resolved by discussion. The inverse variance method was used to pool effect sizes.

MAIN RESULTS

We identified four trials assessing the efficacy of PCV in reducing the incidence of IPD, two on x-ray confirmed pneumonia as outcome, and one on clinical pneumonia, with or without x-ray confirmation. Results from pooling HIV-1 negative children from the South African study with the other studies were as follows: the pooled vaccine efficacy (VE) for vaccine-type IPD was 88% (95% confidence interval (CI) 73% to 94%; fixed effect and random effects models), the effect measure was statistically significant (p <0.00001) and there was no heterogeneity (p = 0.77I2 0%); the pooled VE for all-serotype IPD was 66% (95% CI 46% to 79%; fixed effect model), the effect measure was statistically significant (p <0.00001) and there was no statistical heterogeneity (p = 0.09, I2 51%); the pooled VE for x-ray confirmed pneumonia was 22% (95% CI 11% to 31%; both fixed effect and random effects models) and there was no statistical heterogeneity (p = 0.80, I2 0%). Analyses that included all the children in the South African study (HIV-1 negative and HIV-1 positive children) and pooled with data from the other studies gave very similar results.

REVIEWERS' CONCLUSIONS

PCV is effective in reducing the incidence of IPD from all serotypes but exerts a greater effect in reducing VT IPD. Although PCV is also effective in reducing the incidence of x-ray confirmed pneumonia, there are still uncertainties about the definition of this outcome. Additional randomised controlled trials are currently in progress.