‘Night owls’ at increased risk for suicidal thoughts

People who spent more time awake at night had increased risk for recent suicidal ideation, whereas more time awake in the morning reduced this risk, according to results of a survey study published in The Journal of Clinical Psychiatry.

“Sleep disorders such as insomnia or nightmares are linked to increased risk for suicide,” Andrew S. Tubbs, BSc, of the department of psychiatry at the University of Arizona, told Healio Psychiatry. “We hypothesized that timing of sleep might also affect suicide risk, particularly if someone is awake at a time when they are supposed to be asleep (ie, night).

“We found some preliminary evidence to support this hypothesis in a previous study of community dwelling adults, but we wanted to confirm our findings using a large, nationally representative sample to minimize sampling bias,” Tubbs added.

Tubbs and colleagues analyzed data of 10,166 participants (51.1% women) of the U.S. National Health and Nutrition Examination Survey between 2015 and 2018 who had complete data available on suicidal ideation status, time to bed and time out of bed. They estimated correlations between time being awake and suicidal ideation using population-weighted logistic regression models.

Results showed suicidal ideation in the past 2 weeks among 385 participants, reflecting a population-weighted prevalence of 3.37% (95% CI, 2.85-3.87). After adjusting for sociodemographic factors and symptoms of sleep disorders, but not after adjusting for the severity of depression symptoms, the researchers noted an association between being awake between 11 p.m. and 5 a.m. and suicidal ideation (OR = 1.16; 95% CI, 1.08-1.24 per hour). However, being awake between 5 a.m. and 11 a.m. appeared to reduce risk for suicidal ideation (OR = 0.77; 95% CI, 0.7-0.85 per hour) in all models.

“It may be that individuals who naturally gravitate to later sleep schedules (so-called night owls) are naturally at a higher risk for suicide, as has been shown in other studies,” Tubbs said. “However, it is also possible that being awake at night is a modifiable risk factor for suicide — that is, by reducing nocturnal wakefulness and/or increasing morning wakefulness, we can reduce a person's risk for suicidal thoughts or behaviors.

“We plan to test this hypothesis using clinical studies in at-risk individuals in the hopes that sleep timing can be leveraged to reduce suicide risk,” Tubbs added.