http://www.psychiatrictimes.com/geriatric-psychiatry/thyroid-may-hold-cognitive-key?rememberme=1&elq_mid=2773&elq_cid=176288

Basically, treating dementia with donezepil (a cholinesterase inhibitor) used to be a 50-50 proposition, but now this Taiwanese study showed that having higher T4 levels before treatment predicted response to the drug. This suggests a relationship between thyroid function (and cortisol BTW) and neurodegeneration/dementia. Other studies link dementia to number of general anesthesias and surgery, and another study between obesity and dementia. Dementia remains quite underdiagnosed.

JW