Benefit of pulmonary subspecialty care for children with sickle cell disease and asthma

The impact of obstructive sleep apnea in children with sickle cell disease and asthma

INTRODUCTION

Asthma and obstructive sleep apnea (OSA) are chronic diseases that disproportionately affect children with sickle cell disease (SCD). The literature describes the negative impact that both conditions have on children with SCD separately; however, the effect of OSA on asthmatic children with OSA is less specific. We hypothesized that the presence of OSA in children with SCD and asthma is associated with specific hematologic markers, worse clinical outcomes, and greater healthcare utilization.

METHODS

We retrospectively evaluated children with both SCD and asthma who underwent polysomnography (PSG). We assessed their demographic information, PSG data, hematologic indices, and healthcare utilization based on the concurrent presence of OSA.

RESULTS

Fifty-nine percent of the cohort had OSA with a lower oxygen saturation (SpO2 ) nadir (87% vs. 93%, p < 0.001) and a lower median daytime SpO2 (96.5% vs. 98.5%, p < 0.05); those with OSA were more likely to have the hemoglobin SS genotype (86% vs. 46.5%, p = 0.03). Additionally, those with OSA had a higher mean corpuscular volume (87 vs. 77.2 fL, p = 0.03) and reticulocyte count (10.1% vs. 5.5%, p < 0.01). There was no difference in asthma severity or healthcare utilization between those with OSA and those without OSA.

DISCUSSION

Overall, children with SCD and asthma might be at increased risk for developing OSA, and screening for sleep-disordered breathing should be incorporated as part of their routine care.

Description of a Colocated Comprehensive Care Model for People With Sickle Cell and Comorbid Pulmonary Disease

Comorbid pulmonary complications in people with sickle cell disease (pwSCD) are associated with high rates of morbidity and mortality, and poor access to care contributes to poor outcomes among this particularly high-risk pwSCD. Our purpose was to describe the population served and the resources required for hematology, pulmonary, nursing, respiratory therapy, social work, genetics, psychology, and school liaison providers to see these patients in an integrated clinic. We abstracted demographic, medication, clinical, and diagnostics data of the pwSCD seen at least once in this clinic from February 1, 2014 to December 10, 2020 from the electronic medical record and identified 145 unique pwSCD. Abnormal lung function and bronchodilator responsiveness were detected in 31% and 42% of participants respectively. Sleep abnormalities were found in over two-thirds of those screened and 65% had ≥1 previous acute chest syndrome episode. This clinic also allowed for direct provider communication and required relatively limited resources to serve a large number of severely affected pwSCD. Given the degree of abnormal respiratory variables detected and the limited resources required to implement this model, studies are warranted to evaluate whether it has the potential to improve outcomes in high-risk populations.

Screening for asthma in preschool children with sickle cell disease

BACKGROUND

Asthma in preschool children is poorly defined, proving to be a challenge for early detection. The Breathmobile Case Identification Survey (BCIS) has been shown to be a feasible screening tool in older SCD children and could be effective in younger children. We attempted to validate the BCIS as an asthma screening tool in preschool children with SCD.

METHODS

This is a prospective, single-center study of 50 children aged 2-5 years with SCD. BCIS was administered to all patients and a pulmonologist blinded to the results evaluated patients for asthma. Demographic, clinical, and laboratory data were obtained to assess risk factors for asthma and acute chest syndrome in this population.

RESULTS

Asthma prevalence (n = 3/50; 6%) was lower than atopic dermatitis (20%) and allergic rhinitis (32%). Sensitivity (100%), specificity (85%), positive predictive value (30%), and negative predictive value (100%) of the BCIS were high. Clinical demographics, atopic dermatitis, allergic rhinitis, asthma, viral respiratory infection, hematology parameters, sickle hemoglobin subtype, tobacco smoke exposure, and hydroxyurea were not different between patients with or without history of ACS, although eosinophil was significantly lower in the ACS group (p = 0.0093). All those with asthma had ACS, known viral respiratory infection resulting in hospitalization (3 RSV and 1 influenza), and HbSS (homozygous Hemoglobin SS) subtype.

CONCLUSION

The BCIS is an effective asthma screening tool in preschool children with SCD. Asthma prevalence in young children with SCD is low. Previously known ACS risk factors were not seen, possibly from the beneficial effects of early life initiation of hydroxyurea.

The Cardiopulmonary Complications of Sickle Cell Disease

Sickle cell disease (SCD) is a genetic hemoglobinopathy associated with extensive morbidity and early mortality. While there have been recent improvements in available disease-modifying therapies for SCD, cardiopulmonary complications remain a major risk factor for death in this population. We provide an overview of current knowledge regarding several of the major acute and chronic cardiopulmonary complications in SCD, including: acute chest syndrome, airway disease, lung function abnormalities, nocturnal hypoxemia and sleep disordered breathing, pulmonary vascular disease, and sickle cell cardiomyopathy.