Transient - lasts one or two nights, or persists for a week or two. Intermittent - transient insomnia that recurs from time to time. Transient insomnia is often caused by stress. Most of us have had a night or two where some niggling worry won't let us rest. Chronic insomniacs don't have as clear-cut a problem.
Doctors say the condition seems to run in families.
When she began a new job, insomnia became routine, proving the stress link. In the book, The Promise of Sleep, co-authors William C. Dement, M.D., Ph.D., and Christopher Vaughan, say insomnia isn't a sleeping disorder at all. Rather, it's a symptom. Doctors often look at it as a single disorder or disease, but it isn't curable like gallstones or appendicitis. That's why sufferers and their doctors need to look for a cause they can eliminate rather than treat the symptom without getting at the root.