I doubt that it will. I use a digital camera at 14,000+ feet fairly routinely (and only use it below 6000 feet or so when I travel). Aircraft have used cameras with little or no modification for quite a while, often at considerably higher altitudes than you're considering. Many are different because they're specialized, (e.g., shooting only in infrared or other narrow range of color), but quite a few use pretty standard parts too (e.g., the 105 Micro Nikkor lens has been used for a fair amount of aerial photography).
The only thing I can think of right off isn't the camera or the altitude themselves, but that at altitude the temperature is generally a lot lower, which can reduce the power you get from your batteries. If it's very cold, you're often better off with at least two batteries, so you can carry one in a pocket (or whatever) where it'll stay warm, and you can swap the two as needed.
Edit: one other thing I should mention: at higher altitudes, you also get quite a bit more UV light, so a good UV filter can be extremely useful, even if you don't normally use one at lower altitude.