Before people sound off too bad, this is the Big Five personality construct of "neuroticism". The word has negative connotations, I know, but it is a
personality construct, not a direct measurement of actual disorder or mental instability. Everyone is Big-Five-neurotic to some extent or another. If you want, you could recast it as "vigilance" or, with a similar valence but using less scary words, "tendency to worry". Basically, this study is showing that areas where there are lots of worriers are also areas that swung towards Trump.
Anyway, this is sort of unsurprising. Previous studies of Big Five traits by state in the US have shown there's sort of a "neuroticism belt" from Appalachia down through Arkansas, which are places that unsurprisingly voted very strongly for Trump. If you want to see the map, check out page 32 in
this pdf.
