OBJECTION (well that was dramatic)
Anyway your element is like the ultimate projection of you personality, so if you have a near death experience and start being like some whole new person, your element changes.
My Element is Water, because of my Calm, still and flowing personality, but with all these fine attributes, i tend to be very quiet in public/when i'm not with friends. So if i decided to be more outgoing, dominating and self confident, i feel my personality may change from a calm water to a self confident Fire. Get my point?
Now you may be speaking in terms of astrology ,my astrological sign is also water, but i think it's coincidence. Now people will not always match there astrological sign, and that's great :D Your astrological Element is not your personality :D