Dementia in Down Syndrome

As people with Down syndrome (DS) are living longer, they are at a higher risk of developing dementia, particularly Alzheimer’s disease. This is due to the presence of an extra copy of chromosome 21, which carries a gene linked to the production of amyloid protein—a key factor in Alzheimer’s.

Dementia tends to develop earlier in people with DS, often in their 40s or 50s. However, recognising the early signs can be challenging, as changes in memory, behaviour, or daily functioning may overlap with other health conditions such as sensory impairments, depression, or thyroid issues.

Key Findings in Research

Biological Factors and Early Detection

Recent research from the Trisomy 21 Research Society (T21RS) has highlighted key biological processes linked to dementia in individuals with DS:

  • Amyloid Protein Build-Up: The extra copy of chromosome 21 leads to increased amyloid-beta plaque formation in the brain, a hallmark of Alzheimer’s disease.

  • Nerve Growth Factor (NGF) Disruption: Studies have found that individuals with DS and dementia exhibit altered NGF metabolism, particularly in the frontal cortex, which affects judgment and reasoning.

  • Biomarkers for Early Diagnosis: Measuring proNGF (a precursor to NGF) and related proteins in blood or cerebrospinal fluid could help detect Alzheimer’s in people with DS before symptoms appear. This early detection could enable earlier interventions to slow cognitive decline.

Current and Emerging Treatments

Existing Medications

  • Cholinesterase Inhibitors: Drugs like Donepezil, Rivastigmine, and Galantamine are used to treat Alzheimer’s in the general population, with some studies suggesting potential benefits in individuals with DS. However, results are mixed, and side effects must be carefully monitored.

  • Anti-Amyloid Therapies: New drugs such as Donanemab are being tested to target and reduce amyloid plaques. Clinical trials are being planned to assess their effectiveness specifically for people with DS.

Research into Future Treatments

  • Gene Editing Approaches: Scientists are exploring gene-editing techniques (e.g., CRISPR-Cas9) to regulate the overexpression of genes linked to Alzheimer’s in DS.

  • DYRK1A Inhibitors: DYR533 is a drug in development that aims to reduce the effects of DYRK1A, a gene linked to neurodegeneration in DS.

  • Vaccine Development: Clinical trials, such as the ABATE study, are testing vaccines designed to prevent amyloid build-up in people at high risk for Alzheimer’s, including individuals with DS.

The Importance of Holistic Care

While there is no cure for dementia, a combination of medical management, lifestyle changes, and early intervention can improve quality of life. Regular cognitive assessments, structured routines, and social engagement can help slow decline.

Research continues to advance, offering hope for better treatment and prevention strategies for people with Down syndrome and dementia. Staying informed about new clinical trials and emerging therapies is crucial for families and healthcare professionals supporting individuals with DS.

Information from DSA

chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.downs-syndrome.org.uk/wp-content/uploads/2020/06/2018.09.Alzheimers-Disease_DSMIG.pdf