Periodontal disease appears to be a substantial contributor to Alzheimer’s disease in people with Down syndrome, according to a new review published in Alzheimer’s & Dementia.
Researchers found that early colonization of pathogens, increased numbers of pathogens, and innate pro-inflammatory traits appear to contribute to the progression of Alzheimer’s disease in individuals with Down syndrome.
“Periodontal bacteria, bacterial products, and periodontal derived cytokines produced locally and systemically could reach the brain and amplify brain cytokine pools. The keystone pathogens P. gingivalis, T. forsythia, and T. denticola have survival advantage and ability to reach distant sites such as the brain. Then, bacteria, their products, and cytokines will act on the already primed glial cells because of the DS genetic factors, resulting in an amplified neuroinflammation and progression of AD.”
They also noted that an impaired immune system—characteristic of Down syndrome—likely also contributes to severe local and systemic inflammatory responses.
Periodontal disease often develops earlier (as early as six years of age) and is more severe in people with Down syndrome. Likewise, individuals with the disorder are at a significantly increased risk for Alzheimer’s disease, with some reports showing that more than 50% of people with Down’s syndrome develop some form of dementia in their lifetime.
Down syndrome affects approximately one in every 700 babies born in the United States. Thanks to advancements in healthcare, the average life expectancy of people with the disorder has risen drastically in the past few decades—from 10 years in 1960 to nearly 50 in 2007.
Since periodontal disease almost always precedes Alzheimer’s disease in people with Down syndrome, researchers concluded, the relationship between periodontal disease and Alzheimer’s may be causal—underlining the importance of preventive periodontal care, starting at an early age.