A groundbreaking study conducted by researchers from the University of Southern California and the Karolinska Institute in Sweden, analyzed data from over 45,000 Swedish twins, focused on 90 pairs of identical twins and 288 pairs of fraternal twins where one twin was diagnosed with dementia.
The study found that if one twin is diagnosed with dementia, the undiagnosed twin sibling is also at a higher risk of a shorter lifespan. Published in the journal Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, the study shows that short life expectancy is not solely due to dementia but may also be due to shared genetic and environmental factors.
Does having an identical twin with dementia mean you’ll get it too? Well, it’s a bit of both yes and no.
Identical twins share 100% of their genetic material, making them genetically identical. This means that if one twin has a genetic predisposition to dementia, the other twin shares the same genetic risk factors.
Twins that shared similar environments throughout their lives, including education, diet, physical activity, and exposure to pollutants. If certain environmental factors contribute to the twin’s dementia, such as chronic stress or unhealthy lifestyle choices, the undiagnosed twin may also be exposed to these same environmental risks.
Although having an identical twin diagnosed with dementia doesn’t mean you’ll definitely get it too, but you are at risk of developing one.
This study highlights the importance of considering both genetics and environment in dementia research and care planning.
It also emphasized the lifelong impact of early life choices, suggesting that healthy habits and education in childhood can significantly reduce the risk of developing Alzheimer’s Disease and Dementia later in life.
