Alzheimers in one sibling increases risk of shortened lifespan for others

New USC Research Reveals Alzheimer’s Diagnosis in Sibling Increases Risk of Shorter Lifespan for Other Family Members

A new study conducted by researchers at the University of Southern California (USC) based on data from the Swedish Twin Registry suggests that an Alzheimer’s diagnosis in a sibling can lead to a shortened lifespan in other family members, even if they don’t have dementia themselves. This groundbreaking research, published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association, highlights the combined influence of genetics and environment in affecting longevity.

The research team initially hypothesized that the difference in lifespan between twins, where one developed dementia and the other did not, would be similar to unrelated individuals. However, their findings revealed a surprising increased risk of mortality beyond just the impact of dementia. The study included 90 pairs of identical twins and 288 pairs of fraternal twins, in which one twin had dementia while the other did not.

Both identical and fraternal twins who had a sibling with dementia demonstrated a shortened life expectancy compared to individuals without a sibling with dementia. These findings suggest that dementia alone does not solely cause a shortened lifespan, but rather a combination of shared genes and environmental factors, including conditions like cardiovascular disease.

Furthermore, the study highlights the significance of early life factors in reducing the risk of developing dementia later in life. Factors such as maintaining a healthy diet, engaging in regular exercise, and pursuing education were identified as potential protective measures against dementia.

The research aimed to provide families with valuable information to make informed financial and end-of-life decisions when dealing with dementia. Understanding the potential impact of genetics and environment on lifespan can help families plan for the future and take preventive measures.

The study was supported by grants from the National Institutes of Health, the Swedish Research Council for Health, Working Life and Welfare, as well as various foundations and institutions. The findings underscore the importance of ongoing research in the field of Alzheimer’s and dementia and the need for further exploration of the interplay between genetics and environmental factors in shaping health outcomes.