There is a growing appreciation among health specialists and the general public that nightmares are a frequent sleep problem with important consequences for sleep quality and mental health. Large student and community-based epidemiological studies across different countries indicate that 8% to 29% of adults report monthly nightmares while 2% to 6% report weekly nightmares. Community surveys assessing incidence of nightmare “problems” rather than frequency found that between 5% and 8% of the adult general population report a current problem with nightmares, while about 6% report a past problem.
Finally, one of our own studies based on almost 10 000 dream reports collected in home dream logs from over 550 participants showed almost 3% of all prospectively collected dream narratives were nightmares (very disturbing dreams that wake up the dreamer) while bad dreams (disturbing dreams which do not cause the dreamer to awaken; they are remembered only after being awakened by external factors such as an alarm clock or later during the day) accounted for almost 11% of the dream reports. Thus almost 15% of all remembered dreams are considered to be highly disturbing dreams.