Those with Down syndrome have a higher risk of developing Alzheimer’s disease. The extra copy of chromosome 21 contains a gene called the APP gene, which produces a protein that has links to the formation of plaques on the brain.

Down syndrome is a genetic condition that occurs due to the presence of an extra copy of chromosome 21. It leads to intellectual disabilities, certain physical characteristics, and an increased risk of certain health conditions.

Alzheimer’s disease is a neurodegenerative disorder that causes progressive cognitive decline, memory loss, and other cognitive impairments. It is the most common cause of dementia in older adults, affecting memory, behavior, and thinking.

This article will look at the connection between the two conditions.

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People with Down syndrome have an increased risk of developing Alzheimer’s disease as they age.

Within the extra copy of chromosome 21 in those with Down syndrome, there is a gene called the APP gene. This gene produces a protein called amyloid precursor protein (APP).

The body can process this protein into beta-amyloid, which is a substance that accumulates in the brains of those with Alzheimer’s disease, forming plaques that characterize the condition.

The prevalence of Alzheimer’s disease in people with Down syndrome is significantly higher than in the general population.

According to research from 2019, almost all people with Down syndrome show some signs of beta-amyloid deposits in their brains by the age of 40.

The risk continues to increase with age, and by the age of 60, around 50% of people with Down syndrome have developed clinical symptoms of Alzheimer’s disease.

However, the exact prevalence rates can vary according to various factors, including the specific research population and the criteria scientists use to diagnose Alzheimer’s disease.

The likelihood of a person with Down syndrome developing Alzheimer’s disease over a lifetime exceeds 90%.

While there is no surefire way to eliminate the risk of developing Alzheimer’s disease for people with Down syndrome, certain lifestyle factors and interventions may help lower the risk or delay its onset.

A person can aim to address modifiable risk factors, which can include:

People also need to attend regular medical checkups. Regular medical checkups and screenings can help detect any changes or early signs of cognitive decline. Early detection allows for timely intervention and management.

They can also help to address any modifiable risk factors for Alzheimer’s disease.

The early signs of Alzheimer’s disease in people with Down syndrome can sometimes differ from those in the general population.

Early symptoms of Alzheimer’s disease in people with Down syndrome may manifest as a reduced interest in social interactions and conversations and a decreased enthusiasm for activities they once enjoyed. They might also exhibit feelings of sadness, anxiety, and fear.

Their ability to pay attention may decline, and they may find it challenging to remember new information or find the right word. They may also take longer to respond to new information or scenarios.

Behavioral changes can include irritability, uncooperativeness, and even aggression. Restlessness and sleep disturbances might also become apparent.

Additionally, seizures that start in adulthood, alterations in coordination and walking, and heightened noisiness or excitability could indicate the early stages of the condition.

Generally, the stages of dementia in Down syndrome follow a pattern similar to the stages of dementia in the general population. However, the onset and progression might differ due to the underlying genetic factors.

Health experts typically categorize the stages of dementia as follows:

  • Early stage: People may develop mild cognitive changes. Memory problems and difficulty with tasks might become noticeable. The person can still perform many activities independently.
  • Middle stage: Cognitive decline becomes more evident, and memory loss and communication difficulties worsen. Behavioral and personality changes may be more apparent, while assistance with daily activities is usually necessary.
  • Late stage: Severe cognitive and functional impairment occurs. People may require full assistance with daily activities, as they might have difficulty with mobility, communication, and self-care. Physical health issues may also become more prevalent.

People with Down syndrome are more likely to develop Alzheimer’s disease than those without Down syndrome.

Ongoing research aims to decipher the mechanisms underlying this link, with the hope of developing interventions to delay or mitigate the effects of Alzheimer’s disease in people with Down syndrome.