No Link Found Between Nightmare Severity and Next-Day Suicidal Ideation Severity

A study found although nightmare severity did not correlate with next-day suicidal ideation severity, there was a strong positive relationship between suicide severity on any given day and the severity of suicidal ideation the following day. The data was presented at SLEEP 2024, the 38th annual meeting of the Associated Professional Sleep Societies, in Houston, Texas.¹

Nightmares are considered a significant risk factor for suicidal ideation. Studies suggests nightmare severity is a significant predictor for suicidal ideation severity, but the discovered short-term relationships needed further research.

A 2017 study found both frequent and occasional nightmares increased the suicide risk, but the effect size of the association was not large. The finding suggested a dose dependent risk where an increase in nightmare frequency increases the risk for suicide.²

According to the Centers for Disease Control and Prevention, suicide is the leading cause of death.³ An estimation of 12.3 million US adults experienced suicidal ideation in 2021. Risk factors for suicide include previous suicide attempts, feelings of hopelessness or worthlessness, social isolation, agitation, experiencing stressful life events, substance use problems, suicidal thoughts with access to firearms in the home, underlying psychiatric disorders, a family history of mental disorders, medical conditions linked to depression and suicidal thinking, and being a part of the LGBTQ community in an unsupportive family or environment.⁴

The more recent study presented at SLEEP 2024, led by Sage Robins, from the department of psychology at Brigham Young University, sought to determine the daily relationship and directionality between nightmare severity and suicidal ideation severity.¹

They recruited 26 participants, 8 male and 18 female (aged 19 – 38 years) who reported being suicidal. Over a period of 10 – 21 days, participants completed a sleep survey every morning and night regarding their suicidal questions and nightmare experiences.

In the morning, participants filled out a sleep diary, answering questions about their nightmare severity the previous night. At night, they would complete a survey about the severity of suicidal ideation they experienced that day.

Investigators analyzed the survey responses with a 2-level cross-lagged panel model using Bayesian methods.They estimated the cross-lag effects of nightmare dream severity and suicidal ideation severity without adjusting for covariates.

The team observed suicide severity on any day predicted the suicide severity of the next day (P = .008). However, nightmare severity did not predict suicide severity or next-day suicide severity (P = .440). Additionally, nightmares did not predict nightmares the following day (P = .067).

“Previous studies have found nightmares to be a strong predictor of suicidality over months and years, suggesting that this relationship may only be found within long-term considerations,” investigators concluded. “More research may be necessary to fully understand the relationship between nightmares and suicidality.”

References

1. ^{Robins, S, Larson, A, Kay, D. Suicide and Nightmares: Understanding Predictive Factors of Suicidality. Abstract presented at SLEEP 2024. Houston, TX. June 1-5, 2024.}
2. ^{Sandman N, Valli K, Kronholm E, Vartiainen E, Laatikainen T, Paunio T. Nightmares as predictors of suicide: an extension study including war veterans. Sci Rep. 2017;7:44756. Published 2017 Mar 15. doi:10.1038/srep44756}
3. ^{Facts About Suicide. Centers for Disease Control & Prevention. https://www.cdc.gov/suicide/facts/index.html. Accessed June 1, 2024.}
4. ^{Suicide and Suicidal Thoughts. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/suicide/symptoms-causes/syc-20378048. Accessed June 1, 2024.}