Resources/Down Syndrome Information/Health and Medical
People with Down syndrome are at an increased risk of Alzheimer’s disease because of the presence of three copies of chromosome 21. Chromosome 21 contains more than 300 genes, including several associated with Alzheimer’s disease, one of which is the amyloid precursor protein gene (APP). This and other genes are associated with the plaques that accumulate in the brain and inflammation and oxidative stress that occurs early in development. These may progressively lead to mitochondrial impairment, degeneration of neuronal pathways, accelerated aging, and loss of brain cells in the cerebral cortex and hippocampus. Although in Down syndrome Alzheimer’s, brain pathology is frequently seen in the 40s, not everyone with Down syndrome exhibits the clinical signs of Alzheimer’s, which usually presents in the 50s and 60s.
Current scientific evidence from studies of normal aging and Alzheimer’s in the general population points to a healthy Mediterranean diet with fish, nuts, legumes, fruit and vegetables, early treatment of sleep disorders, such as sleep apnea, moderate daily exercise, maintaining a healthy weight, monitoring cardiovascular health, maintaining social connections, and regularly learning new things as the best ways to try to reduce the risk of Alzheimer’s. New research focuses on discovering novel therapeutic interventions, including pharmaceutical and non-pharmaceutical approaches. So far, prevention is still the best tool we have, as there is no effective treatment. We hope there will soon be more clinical trials dedicated to helping older people with Down syndrome find ways to slow or prevent dementia.
When there is a change in behaviour, or decline in skills, it is essential to rule out other treatable conditions before assuming Alzheimer’s. According to Dr Brian Chicoine, in Mental Wellness in Adults with Down Syndrome: A Guide to Emotional and Behavioural Strengths and Challenges (2006):
“If we had assumed that all our patients over the age of 40 with declines in function had Alzheimer’s disease, we would have been wrong 75% of the time. Only 25% had Alzheimer’s disease. The other 75% are being successfully treated for other conditions. There is no cure for Alzheimer’s disease at this time, so detection of treatable conditions is a vital element of patient care.”
Some of these treatable conditions include thyroid disease, depression, B-12 deficiency, celiac disease, untreated sleep apnea, hearing or vision problems, and a range of other conditions.
The LowDOWN Podcast, Episode 1-3: Dr Brian Chicoine: Optimizing Physical and Mental Health for Adults with Down Syndrome (Apr. 29, 2020)
Supporting Communication in Down Syndrome and Alzheimer’s Disease
National Down Syndrome Society: Alzheimer’s Disease and Down Syndrome
National Task Group on Intellectual Disabilities and Dementia Practices