Yep. With rare exception, that's the case. The Holter shunt, the first to have a one-way valve, was patented in the '50s. It was also the first to be made of a flexible silicone-rubber/plastic so as to allow for more normal body movement and better tolerance by the body to the material.

As for your other question, many that I know who are older than I am (I'm 41) are not doing nearly as well and also have other age-related issues to deal with (osteoporosis, thyroid conditions [which I also have], etc). Anyone who also has complications/secondary conditions related to hydro should be aware of how they or their treatment may affect those other age-related issues (e.g. long-term anti-sz med use may deplete vit D., resulting in increased risk of osteoporosis). Aside from that, there's also the effect of what decades of hydro can do to the brain, so it's not surprising that many 40+ers have serious problems.

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