Pulmonary complications in children with Down syndrome: A scoping review

Global, regional, and national impact of Down syndrome on child and adolescent mortality from 1980 to 2021, with projections to 2050: a cross-sectional study

Introduction

Down syndrome, resulting from trisomy 21, is a prevalent genetic disorder. Despite improvements in life expectancy and quality of life due to medical progress, children and adolescents (under the age of 20 years) with Down syndrome still face higher mortality rates. Future research is essential to elucidate the epidemiological patterns and trends in Down syndrome among children and adolescents, enabling the development of effective prevention and intervention strategies to improve survival and health outcomes.

Methods

This study draws on Global Burden of Disease (GBD) 2021 mortality data for children and adolescents with Down syndrome. Pearson's correlation coefficient was leveraged to assess the relationship between Down syndrome mortality and the Socio-demographic Index (SDI). The estimated annual percentage change (EAPC) in mortality was calculated to track temporal trends, and the Bayesian age-period-cohort (BAPC) model was employed to forecast future mortality.

Results

Over the past 42 years, there have been fluctuations in mortality among children and adolescents with Down syndrome. Globally, deaths have decreased by 22.8% from 26.95 thousand (95% uncertainty interval [UI], 10.10-74.66 thousand) in 1980 to 20.81 thousand (95% UI, 14.18-36.49 thousand) in 2021. Furthermore, BAPC model projections indicate a sustained reduction in mortality for children and adolescents with Down syndrome. Predominantly, deaths occur in 0-4 age group, with higher death rates in Low SDI regions, and notably, the number and rate of female patients exceed those of male patients. Intriguingly, a negative correlation was observed between death rates and higher SDI.

Conclusion

Most countries have seen a decline in Down syndrome deaths among children and adolescents over the last 42 years, but a few high SDI countries are witnessing an increase. Future health interventions should prioritize these countries, focusing on resource allocation, infrastructure, and health education. Continued efforts on care for the 0-4 age group with Down syndrome are crucial to further reducing deaths in this age group.

Oscillometry Phenotypes in Children With Down Syndrome

OBJECTIVE

To evaluate lung function patterns measured by oscillometry in children with Down syndrome and determine associations with pulmonary diagnoses that may co-occur with Down syndrome, including evidence of dysphagia, obstructive sleep apnea, tracheomalacia, and congenital heart disease.

STUDY DESIGN AND PATIENTS

Cross-sectional study of children with Down syndrome who were enrolled during 2019-2022 at ages 4-18 years old.

MEASUREMENTS

Children performed oscillometry before and after albuterol administration to obtain respiratory impedance measures of resistance (R) and reactance (X). Aspiration from swallow study, obstructive sleep apnea from polysomnogram, tracheomalacia from flexible bronchoscopy, and congenital heart disease diagnoses were obtained from the electronic medical record.

RESULTS

In 50 children with Down syndrome, more negative X (median X5 z-score -0.93 [IQR - 2.15, 0.17]) was observed compared to a z-score of zero representing the mean in a pediatric reference population, but R was not increased at any frequency. Neither R nor X were related to tested pulmonary co-occurring diagnoses. Frequency dependence of resistance (R5-19) was elevated (median z-score 0.50 [IQR - 0.01, 1.14]), which, in combination with the more negative X, could indicate heterogeneity in peripheral and/or central airway sizes. After bronchodilator, R5 and AX decreased -26% [IQR -32%, -12%] and -43% [IQR -58%, -28%], respectively, and X5 increased 31% [IQR 12%, 45%], indicating physiological improvement.

CONCLUSIONS

In our population, a phenotype of lower lung compliance in 50% of children with Down syndrome was not associated with the presence of co-occurring pulmonary diagnoses. More work is needed to understand if this may be related to their diagnosis of DS.

Choking in Down Syndrome: Clinical and Forensic Perspectives

Choking is a serious yet often overlooked risk among individuals with Down syndrome (DS), primarily due to their anatomical and neuromuscular vulnerabilities. This case report discusses the sudden choking-related death of an 11-year-old child with DS, emphasizing both clinical and forensic perspectives. The child developed respiratory distress while eating and became unresponsive, leading to a medicolegal investigation. A comprehensive postmortem examination, including verbal autopsy, postmortem computed tomography (PMCT), and traditional autopsy, was performed. PMCT revealed a foreign body obstructing the laryngeal inlet, along with pulmonary interstitial emphysema and diffuse pulmonary edema - findings that strongly suggested antemortem choking. The traditional autopsy also confirmed the presence of a soya chunk completely blocking the laryngeal inlet, with all findings aligning with the PMCT results. This case highlights the role of PMCT as a valuable, non-invasive tool in diagnosing choking-related deaths, especially in cases with minimal external indicators. Given that swallowing difficulties in DS persist into adulthood, early screening, caregiver education, and dietary modifications are critical preventive measures. Training caregivers to recognize choking risks, adopt safe feeding practices, and respond promptly to airway obstruction could significantly reduce such fatalities. Forensic pathologists should also consider choking as a differential diagnosis in sudden unexplained deaths, with PMCT aiding in a thorough assessment of airway compromise. Strengthening preventive strategies and improving diagnostic approaches can help mitigate the risk of choking-related deaths in individuals with DS.

Dysregulated airway epithelial antiviral immunity in Down Syndrome impairs type III IFN response and amplifies airway inflammation during RSV infection

Trisomy 21 (TS21), also known as Down syndrome (DS), increases pediatric mortality risk from respiratory syncytial virus (RSV) by nine-fold, yet its underlying immunological basis remains unclear. Here, we investigated RSV-induced immunological responses in TS21 airway epithelial cells (AECs), the primary site of respiratory virus entry and host defense. TS21 AECs exhibit hyperactive interferon (IFN) signaling and reduced RSV infectivity, but they also show impaired type-III IFN responses during viral infection. Furthermore, TS21 AECs demonstrate heightened production of proinflammatory mediators CXCL5 and CXCL10 both before and after RSV exposure. Infants with DS suffering from severe viral bronchiolitis demonstrate dysregulated airway immune responses in vivo, characterized by diminished type-III IFN levels and increased CXCL5/CXCL10 secretion. Our results indicate that RSV severity in DS is not due to impaired viral control but to dysregulated airway proinflammatory responses, offering new therapeutic opportunities to mitigate the severity of RSV infection in children with DS.

Down syndrome-associated leukaemias: current evidence and challenges

Children with Down syndrome (DS) are at increased risk of developing haematological malignancies, in particular acute megakaryoblastic leukaemia and acute lymphoblastic leukaemia. The microenvironment established by abnormal haematopoiesis driven by trisomy 21 is compounded by additional genetic and epigenetic changes that can drive leukaemogenesis in patients with DS. GATA-binding protein 1 (GATA1) somatic mutations are implicated in the development of transient abnormal myelopoiesis and the progression to myeloid leukaemia of DS (ML-DS) and provide a model of the multi-step process of leukaemogenesis in DS. This review summarises key genetic drivers for the development of leukaemia in patients with DS, the biology and treatment of ML-DS and DS-associated acute lymphoblastic leukaemia, late effects of treatments for DS-leukaemias and the focus for future targeted therapy.

Flexible bronchoscopy in pediatric patients with Down syndrome: A case-control study of the indications, findings, and complications

BACKGROUND

Children with Down syndrome (DS) often undergo flexible bronchoscopies (FB) due to common respiratory symptoms.

OBJECTIVE

To examine the indications, findings, and complications of FB in pediatric DS patients.

METHODS

A retrospective case-control study on FB performed in DS pediatric patients between 2004 and 2021 in a tertiary center. DS patients were matched to controls (1:3) based on age, gender, and ethnicity. Data collected included demographics, comorbidities, indications, findings, and complications.

RESULTS

Fifty DS patients (median age 1.36 years, 56% males) and 150 controls (median age 1.27 years, 56% males), were included. Evaluation for obstructive sleep apnea and oxygen dependence were more common indications among DS (38% vs. 8%, 22% vs. 4%, p < 0.01, respectively). Normal bronchoscopy was less frequent in DS compared with controls (8% vs. 28%, p = 0.01). Soft palate incompetence and tracheal bronchus were more frequent in DS (12% vs. 3.3%, p = 0.024, 8% vs. 0.7%, p = 0.02, respectively). Complications were more frequent in DS (22% vs. 9.3%, incidence rate ratio [IRR] 2.36, p = 0.028). In DS, cardiac anomalies (IRR 3.96, p < 0.01), pulmonary hypertension (IRR 3.76, p = 0.006), and pediatric intensive care unit (PICU) hospitalization before the procedure (IRR 4.2, p < 0.001) were associated with higher complication rates. In a multivariate regression model, history of cardiac disease and PICU hospitalization before the procedure, but not DS, were independent risk factors for complications with an IRR of 4 and 3.1, respectively (p = 0.006, p = 0.05).

CONCLUSION

DS pediatric patients undergoing FB are a unique population with specific indications and findings. DS pediatric patients with cardiac anomalies and pulmonary hypertension are at the highest risk for complications.