Not one or two, but frequent nightmares are major caveats for underlying serious mental problems. Rapid Eye Movement sleep disorder is a rare disorder that causes the person to act violently during dreamy state. This may be a warning sign for major neurologic disorders like Parkinson's and neurodegenerative diseases like Alzheimer's !!
Night owls are more likely to have frequent sleep and mood disturbances than the early sleepers. Evidences suggest people suffering from nightmares and related sleep disorders are more likely to have suicidal tendencies than those not, in addition to other contributing factors.
- Jaskunwar Singh