I don't know how helpful this is, but my husband is a brilliant, literate person who doesn't read very much. If he does, it's mostly reference books, like field guides. He does read the New Yorker and the New York Times, but I would estimate he reads maybe 2 fiction and 3 nonfiction books a year, and that's generous.

He read as a child, but not nearly as avidly as I did. He still scored extremely high on the verbal portions of his SAT and GRE, and he's a great writer. It just doesn't seem to be what excites him. He is musical, visual, and tactile in his hobbies.

FWIW, he reads rather slowly, at least by my estimation. He complains about it. I don't think there is any kind of LD involved, though.