Cynical Mistrust seems to be linked to a  increased risk   for dementia – even after controlling for other risk factors and „substracting“ those factors statistically.
A high level of cynical distrust — for example, believing that no one cares much what happens to you and that it’s safer not to trust anybody — was associated with a threefold risk of developping symptoms of dementia in elderly patients.
The original article can be found here:
http://neurology.org/lookup/doi/10.1212/WNL.0000000000000528
and a commented article about the Research:
http://www.medscape.com/viewarticle/825822?nlid=58143_2052&src=wnl_edit_medn_psyc&uac=97338BZ&spon=12
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