It usually only affects your camera by it either being dead or not.
It is certainly possible that it COULD slow down instead of just break, though.
Did you notice your camera being faster when it had lower shutter count? And does it seem mechanical in its slowness? Or more like software? (for instance, is the shutter sort of getting stuck / hanging? Or is it as snappy as ever but then the camera just sits there thinking?). If there is actual mechanical slowness in your shutter, then it should be VERY obvious insofar as all of your exposures should be wrong. Especially extremely fast shutter speed shots should be off if there's a mechanical issue.
Usually shutters are not worth repairing. Especially for your 1000D, if that's the problem. Would almost definitely cost as much as the camera. Sort of like your engine exploding in an older car.