Excess consumption of diuretics (say, ethanol) can cause hyperuricemia (high levels of uric acid in the blood). So can some of the other ingredients in beer and liquor.
That's why beer and liquor are more commonly associated with gout attacks. But drinking excessively in general can cause it.
EDIT: I'm WAYYYY too late on this. See GerryGout's answer above for a far better response.