The study: https://www.nature.com/articles/s43587-021-00138-z
Critique of the study: https://www.sciencemediacentre.org/e...imers-disease/
One comment:
“ A limitation in the insurance data analysis is a thing we call hidden variables. These are sneaky things we can’t measure that may explain the effect we are seeing. In this case there are many potential hidden variables. For example, walking slower has been associated with increased risk of a dementia diagnosis. Not because walking faster prevents dementia, it is because walking speed correlates with health. Now replace walking with sex life. Previous research has shown that people with the early signs of Alzheimer’s disease are, on average, less sexually active. So sildenafil use could be a spurious correlation – aka a red herring.”