Practice guidelines for communicating a prenatal or postnatal diagnosis of Down syndrome: recommendations of the national society of genetic counselors.

Down syndrome is one of the most common conditions encountered in the genetics clinic. Due to improvements in healthcare, educational opportunities, and community inclusion over the past 30 years, the life expectancy and quality of life for individuals with Down syndrome have significantly improved. As prenatal screening and diagnostic techniques have become more enhanced and widely available, genetic counselors can expect to frequently provide information and support following a new diagnosis of Down syndrome. This guideline was written for genetic counselors and other healthcare providers regarding the communication of a diagnosis of Down syndrome to ensure that families are consistently given up-to-date and balanced information about the condition, delivered in a supportive and respectful manner.

Prevalence of iron deficiency in children with Down syndrome.

OBJECTIVES: To determine the prevalence of iron deficiency (ID) and iron deficiency anemia (IDA) in a sample of children with Down syndrome (DS) and to evaluate the effect of macrocytosis on the diagnosis of ID/IDA in these children. STUDY DESIGN: Children with DS ≥ 12 months of age who were followed at the Duke University Medical Center Comprehensive DS Clinic from December 2004 to March 2007 were screened for ID/IDA with a complete blood count, reticulocyte count, iron panel, and erythrocytic protoporphyrins. RESULTS: A total of 114 children were enrolled, with a median age of 4.7 years. ID was identified in 12 subjects (10%), and IDA was identified in 3 subjects (3%). ID/IDA would not have been accurately diagnosed in 13 of 15 subjects (86%) if red blood cell (RBC) indices alone had been used for screening. Abnormal RBC indices with low transferrin saturation were 100% sensitive for ID/ IDA screening. CONCLUSIONS: Prevalence of ID/IDA in children with DS was comparable with that in the general pediatric population. Macrocytosis had implications for screening of ID/IDA with only RBC indices. We suggest ID/IDA screening in DS children be done with a laboratory panel at least including complete blood count, reticulocyte count, transferrin saturation, and serum ferritin.

Safety and efficacy of rivastigmine in adolescents with Down syndrome: a preliminary 20-week, open-label study.

Individuals with Down syndrome (DS) exhibit a cholinergic deficiency similar to that found in Alzheimer's disease. Cholinesterase inhibitors, used to treat Alzheimer's disease, may improve cognitive function in individuals with DS. This is the first investigation of the safety and efficacy of rivastigmine (an acetyl and butyryl cholinesterase inhibitor) on specific cognitive domains in pediatric DS. Eleven subjects with DS (ages 10-17 years) were treated with a liquid formulation of rivastigmine. Four subjects experienced no adverse events (AEs). Seven subjects reported AEs that were mild, transient and consistent with adverse events typically noted with cholinesterase inhibitors. Significant improvements were found in overall adaptive function (Vineland Adaptive Behavior Scales and Clinician's Interview-Based Impression of Change), attention (Leiter Attention Sustained tests A and B), memory (NEPSY: Narrative and Immediate Memory for Names subtests) and language (Test of Verbal Expression and Reasoning and Clinical Evaluation of Language Fundamentals-Preschool) domains. Improved language performance was found across all functional levels. These results underscore the need for larger, controlled studies employing a carefully constructed test battery capable of measuring the full scope of performance across multiple domains and a wide range of functional levels.

Down Syndrome Disintegrative Disorder: New-Onset Autistic Regression, Dementia, and Insomnia in Older Children and Adolescents With Down Syndrome.

Over a 10-year period in a Down syndrome Clinic, 11 children and adolescents were encountered with a history of new-onset (8) or worsening (3) autistic characteristics. Ten of the 11 (91%) had cognitive decline to a dementia-like state and 9 of the 11 (82%) new-onset insomnia. The mean age at which symptoms developed was 11.4 years (standard deviation = 3.6 years; range 5-14 years), an older age than usual for autistic regression in Down syndrome. Ten of 11 cases (91%) had elevated ("positive") thyroperoxidase antibody titers compared to only 5 of 21 (23%) age-matched control subjects with Down syndrome (P < .001). At follow-up at a mean age of 20.7 years (standard deviation = 3.9 years), 8 of the 11 (73%) were at least somewhat better. Down syndrome disintegrative disorder seems an appropriate name for this newly recognized clinical association, which may be due to autoimmunity.

Safety and efficacy of rivastigmine in adolescents with Down syndrome: long-term follow-up.

Following the completion of a 20-week, open-label study of the safety and efficacy of liquid rivastigmine for adolescents with Down syndrome, 5 of the 10 adolescents in the clinical trial continued long-term rivastigmine therapy and 5 did not. After an average period of 38 months, all 10 subjects returned for a follow-up assessment to determine the safety and efficacy of long-term rivastigmine use. Rivastigmine was well tolerated and overall health appeared to be unaffected by long-term rivastigmine use. Performance change on cognitive and language measures administered at the termination of the open-label clinical trial was compared between the two groups. No between-group difference in median performance change across the long-term period was found, suggesting that the long-term use of rivastigmine does not improve cognitive and language performance. However, two subjects demonstrated remarkable improvement in adaptive function over the long-term period. Both subjects had received long-term rivastigmine therapy. The discussion addresses the challenge of assessing cognitive change in clinical trials using adolescents with Down syndrome as subjects and the use of group versus individual data to evaluate the relevance of medication effects.

Preliminary study of the safety and efficacy of donepezil hydrochloride in children with Down syndrome: a clinical report series.

There is growing evidence to support the use of early central cholinergic enhancement to improve cognitive functioning in individuals with Down syndrome (DS). This report summarizes preliminary safety and cognitive efficacy data for seven children (8-13 years) with DS who participated in a 22-week, open-label trial of donepezil hydrochloride. Donepezil was dosed once daily at 2.5 mg and, based on tolerability, increased to 5 mg/day. Safety assessments were conducted at Week 1 (baseline), Week 8 (2.5 mg donepezil), Week 16 (5 mg) and Week 22 (after the donepezil had been discontinued). Measures of cognitive function were administered at each visit, encompassing the following domains: memory; attention; mood; and adaptive functioning. Donepezil was well tolerated at the 2.5 and 5 mg doses. The side effects were mild, transient, and consistent with the adverse events noted with cholinesterase inhibitors. Some children showed improvement on measures of memory (NEPSY Memory for Names and Narrative Memory) and sustained attention to tasks (Conners' Parent Rating Scales), although increased irritability and/or assertiveness were noted in some patients. Overall, this clinical report series adds to our initial findings of language gains in children with DS treated with donepezil. It also supports the need for larger, double-blind studies of the safety and efficacy of donepezil and other cholinesterase inhibitors for children with DS.

Clinical trials in children with Down syndrome: issues from a cognitive research perspective.

Clinical and translational research play a key role in the transition of basic research discoveries to effective therapies. In Down syndrome (DS), these research approaches are not well utilized or developed to test new therapies to improve cognitive and/or adaptive function in this population. This article reviews the history of clinical trial research in children with DS from a cognitive research perspective and discusses important issues relevant to the conduct of well designed clinical trials for this population. Specific issues addressed include: funding, study design, study medication, subject recruitment and retention, safety, and efficacy challenges. The Duke Down Syndrome Research Team's program of clinical research of cholinesterase inhibitors for individuals with DS serves as the model application for the identified research principles. It is hoped that this article will raise awareness of the unmet need for clinical research in the cognitive and adaptive function of individuals with DS, especially children with DS.