Plasma vitamin C, but not vitamin E, is associated with reduced risk of heart failure in older men.
http://circheartfailure.ahajournals.org/content/6/4/647.long
Accidentally found this 2013 study, and was confounded that that abstract failed to mention how much the risk of heart failure was reduced by higher plasma vitamin C. At least the article is free. If anyone can figure out the answer, please post!