Diurnal variation present in youth suicidal ideation, suicide attempts

Key takeaways:

• Most youth suicide attempts occurred in the evenings and at night.
• Targeting self-critical rumination in the daily lives of youth could reduce suicidal ideation.

INDIANAPOLIS — In a survey of psychiatrically hospitalized youth, more than half of participants reported their most recent suicide attempt occurred in the evening and night. According to researchers, the diurnal variation in suicidal ideation points to the need for increased support in the later hours of the day to decrease youth suicide risk.

“Suicide is the second leading cause of death among adolescents between the ages of 15 and 24 years, and suicidal ideation is a vast risk factor for suicidal behavior, including suicide attempts,” Anastacia Y. Kudinova, PhD, assistant professor of psychiatry and human behavior at the Alpert Medical School of Brown University and a research scientist at Bradley Hospital in Providence, Rhode Island, said during her late-breaking abstract presentation here. “Both suicidal ideation and suicidal behavior have been increasing in the past decade. ... [D]ata from the CDC show that in 2021 ... approximately 20% of high school students had seriously considered suicide.”

She continued, “Much progress has been made in identifying long-term predictors of suicide risk ... however, there’s an urgent need to describe proximal time variants and risk factors for suicide so we can identify who is at a greater suicide risk over the time scale of weeks, days or even hours.”

Kudinova and colleagues sought to expand on previous research demonstrating suicide attempts are higher at night among youth, as well as study the link between time of day and suicidal ideation in a group of youth recruited after partial hospitalization. In a separate cohort, they examined whether this link was mediated by self-critical rumination or self-reassurance.

The first sample included 61 participants with a mean age of 13 years who were recruited mostly from a partial hospital setting. Kudinova and colleagues administered phone app surveys three times per day for 2 weeks to determine suicidal ideation, self-critical rumination and self-reassurance among participants.

According to generalized linear mixed models, suicidal ideation was significantly more frequent later in the day (P < .01).

“Self-critical rumination, not self-reassurance, moderated the risk for suicidal ideation, such that more self-critical youth had higher levels of suicidal ideation later in the day,” Kudinova said.

She added that lower levels of self-critical rumination appear to have a protective effect against increased suicidal ideation throughout the day, and that the findings were maintained after adjusting for current mood and stress levels.

The second study sample was comprised of 165 youth with a mean age of 14 years who were on the inpatient units of the psychiatric hospital. The researchers administered a single-item questionnaire inquiring about the participants’ most recent suicide attempt.

Results showed that most attempts occurred in the evenings and at night (57.6%) followed by daytime (35.2%) and mornings (7.3%), according to Kudinova. Again, findings were maintained after adjusting for stress levels and mood.

“Overall, suicidal ideation attempts appear to be lowest in the morning and greater at nighttime, and the link between time of day and suicidal ideation appears to be strongest among youth with high levels of self-critical rumination,” Kudinova said. “These are preliminary findings and there is need for more data, but the [results] signal, potentially, that there’s a need for availability of clinical providers and support, especially at nighttime and there might be potential for targeting self-critical rumination in daily lives of youth.”

Kudinova acknowledged study limitations, like the modest sample sizes and the lack of assessment of circadian timing and sleep duration, which she said may have a significant role in affecting diurnal variation. Current studies are ongoing, however, that will include these factors, as well as suicidal ideation and self-referential processing at times later than midnight, and the use of social media among this population.