Trends and predictions for survival and mortality in individuals with Down syndrome in Brazil: A 21-year analysis

Critical issue in the identification of Down syndrome and its problems in Central Java, Indonesia: The fact of needing health care and better management

We conducted a cross-sectional study to describe the health care problems of children with Down syndrome in Central Java, Indonesia. A total of 162 children (81 boys, 81 girls) with Down syndrome were included. Congenital heart defects and hypothyroidism were found in about 50%, followed by vision and hearing problems in 27.7% and 17.3%, respectively. Almost half of cases were diagnosed after the first month of age. Advanced maternal age was identified in more than 50%, and less than 10% was based on karyotype analysis. This study describes the essential issues such as critical co-morbidities, delayed diagnosis, advanced maternal age, and lack of (accessibility to) genetic testing facilities; thus, better health care and management is needed.

Anatomical and immunohistochemical analyses of the fusion of the premaxillary-maxillary suture in human fetuses

PURPOSE

The development of the premaxillary-maxillary suture (PMS) in human fetuses and a possible association between the fusion time of the PMS and maxillary deficiency were investigated. Expression of transforming growth factor beta (TGF-β1 and TGF-β3) and of fibulins (fibulin‑1 and fibulin-5) were also investigated.

METHODS

We analyzed 36 human fetus cadavers (19 males, 17 females; average age 23.97 ± 2.57 gestational weeks [gws], range 11-35 gws). Two cases, diagnosed with Down syndrome (DS), were characterized with maxillary deficiency; 34 fetus cadavers did not show any craniofacial abnormalities. The PMS was analyzed anatomically, followed by semi-quantitative immunohistochemical (IHC)-based expression analyses (i.e., TGF-β1/-β3, fibulin-1/-5). Spearman correlation test was conducted to investigate correlations.

RESULTS

In the fetuses without DS, the labial region of the PMS was open at 11 gws, after which it began to ossify from the middle to the upper and lower ends of the suture, typically fusing completely at 27 gws. Fetuses with DS demonstrated complete fusion of the labial region of PMS with a spongy bone structure at 23 gws and those without DS at 27 gws. IHC revealed similar patterns of TGF-βs and fibulins expression in the PMS during the human fetal period. There were significant positive correlations between the expression of TGF-β1 and TGF-β3 (r = 0.64, p = 0.009), TGF-β1 and fibulin‑1 (r = 0.66, p = 0.008), and TGF-β3 and fibulin‑1 (r = 0.67, p = 0.006).

CONCLUSION

Premature fusion of the PMS in the labial region during the human fetal period may be associated with maxillary deficiency, which is related to a class III malocclusion. Overall, the similar expression patterns of TGF-β1, TGF-β3 and fibulin‑1 suggested a close relationship between these factors in regulating the development of the PMS.

Risk for Severe Illness and Death among Pediatric Patients with Down Syndrome Hospitalized for COVID-19, Brazil

Down syndrome is the most common human chromosomal disorder. Whether Down syndrome is a risk factor for severe COVID-19 outcomes in pediatric patients remains unclear, especially in low-to-middle income countries. We gathered data on patients <18 years of age with SARS-CoV-2 infection from a national registry in Brazil to assess the risk for severe outcomes among patients with Down syndrome. We included data from 14,684 hospitalized patients, 261 of whom had Down syndrome. After adjustments for sociodemographic and medical factors, patients with Down syndrome had 1.8 times higher odds of dying from COVID-19 (odds ratio 1.82, 95% CI 1.22-2.68) and 27% longer recovery times (hazard ratio 0.73, 95% CI 0.61-0.86) than patients without Down syndrome. We found Down syndrome was associated with increased risk for severe illness and death among COVID-19 patients. Guidelines for managing COVID-19 among pediatric patients with Down syndrome could improve outcomes for this population.

Global, Regional, and National Burden and Trends of Down Syndrome From 1990 to 2019

Introduction: Down syndrome (DS) is the leading cause of genetically defined intellectual disability and congenital birth defects worldwide. A large population of people diagnosed with DS globally is posing an enormous socioeconomic burden. However, the global burden and trends of DS have not been reported.

Methods: Based on the data from the Global Burden of Disease database in 2019, we analyzed the incidence, prevalence, disability-adjusted life years (DALYs), and death of DS from 1990 to 2019 according to sex, age, regions, and social-demographic index (SDI). Then, age-standardized rates (ASRs) and estimated annual percentage change (EAPC) of these aforementioned indexes were calculated to evaluate the temporal trend of DS. Finally, the association of SDI with DS epidemiological parameters was assessed.

Results: In the past 30 years, the incident cases, age-standardized incident rate (ASIR), and age-standardized prevalent rate (ASPR) of DS first decreased slightly and subsequently increased globally. The number of prevalent cases increased steadily, while the number and age-standardized rate (ASRs) of DALYs and deaths decreased gradually from 1990 to 2019. In the meantime, disease burdens were different across various SDI regions. The prevalent cases and ASPR for both sexes were increasing in all SDI regions except for the high-middle SDI region. At the national level, Brunei Darussalam, Ireland, and Haiti were the top three countries with the highest ASIR in 2019. Georgia was in the top three with the highest increase in ASRs of four parameters, while Serbia was consistently ranked in the top three with fastest declining. Furthermore, we found that ASIR and ASPR were positively correlated with SDI, yet the age-standardized DALYs and age-standardized death rate (ASDR) were negatively correlated with SDI.

Conclusion: In the past 30 years, the burden and trends of DS were heterogeneous across different regions and countries with different sociodemographic characteristics. Great improvements had been achieved in reducing DALYs and deaths globally. However, the increased number and ASRs of incident and prevalent cases in some regions, especially in low SDI regions, were contributing to numerous challenges to public health. The findings may provide valuable information to the development or implementation of more effective measures.

Alzheimer's Disease in the Down Syndrome: An Overview of Genetics and Molecular Aspects

The overexpression of the amyloid precursor protein (APP) gene, encoded on chromosome 21, has been associated in Down syndrome (DS) with the development of early-onset Alzheimer's disease (EOAD). The increase in APP levels leads to an overproduction of amyloid-β (Aβ) peptide that accumulates in the brain. In response to this deposition, microglial cells are active and generate cascade events that include release cytokines and chemokine. The prolonged activation microglial cells induce neuronal loss, production of reactive oxygen species, neuron death, neuroinflammation, and consequently the development of Alzheimer's disease (AD). The intrinsically deficient immune systems in people with DS result in abnormalities in cytokine levels, which possibly contribute to the development of neurodegenerative disorders such as AD. Knowledge about the biomarkers involved in the process of neurodegeneration and neuroinflamation is important for understanding the mechanisms involved in the incidence and the precocity of AD in individuals with DS.

Evaluation of the craniofacial and oral characteristics of individuals with Down syndrome: A review of the literature

The aim of this investigation was to describe the craniofacial and oral characteristics of children and/or adolescents with and without Down syndrome (DS). A bibliographic search of the Medline database (via PubMed), Scopus and SCIELO was performed using the keywords "craniofacial characteristics", "dental characteristics" and "Down syndrome". Systematic reviews, observational cross-sectional and longitudinal studies were included. On the contrary, case reports, letters to the editor, editorials and opinion articles were excluded. 251 articles were recovered, and only 30 fulfilled the selection criteria. DS patients were characterized by reduced dimensions of the maxillary bone, mandible, and skull base, compared to normal patients. Likewise, some of these abnormalities influenced more frequent presentation of a class III malocclusion in these patients. On the other hand, this population group showed a higher prevalence of periodontal diseases, less risk of dental caries, and the presence of alterations in the tongue, lips, dental development and palate morphology. The quality of life of these individuals is affected by difficulties in swallowing, talking, eating or breathing through the nose. In conclusion, the craniofacial and oral characteristics of DS patients present various alterations compared to healthy patients, and these alterations have a negative impact on their quality of life.