Long and short sleep duration are both associated with suicidal ideation in Korean employees

The Impact of Homeostatic and Circadian Sleep Processes on Non-Suicidal Self-Injury and Suicide Urges in Borderline Personality Disorder

OBJECTIVE

Borderline personality disorder (BPD) involves high rates of non-suicidal self-injury (NSSI) and suicidal behaviors, which are often preceded by urges. Disrupted sleep processes have been linked to NSSI and suicidal behaviors. However, it is unclear which specific sleep processes influence NSSI and suicide urges at rest (i.e., baseline) or in response to distress (i.e., reactivity) in BPD, and thus require targeting in BPD-specific interventions. This study examined whether two distinct homeostatic sleep processes (i.e., total sleep time [TST] and time in bed [TIB]), and one circadian sleep process (i.e., chronotype, or tendencies toward early versus late bed and rise times) predict baseline NSSI and suicide urges and urge reactivity in BPD.

METHODS

Forty adults with BPD completed a seven-day sleep diary to measure average TST and TIB. They then completed a questionnaire to measure chronotype and underwent an experiment wherein they rated NSSI and suicide urges at baseline and following an emotion induction.

RESULTS

Generalized estimating equations revealed that higher TST was associated with lower baseline NSSI urges, and lower suicide urge reactivity. Additionally, higher TIB predicted higher NSSI urge reactivity.

CONCLUSIONS

Sleep deprivation and extended time in bed may increase proclivity toward NSSI and/or suicide. Targeting these variables in BPD interventions may ultimately facilitate the reduction of NSSI and suicidal acts. HighlightsHigher total sleep time predicts lower baseline NSSI urges, suicide urge reactivityHigher time in bed predicts higher NSSI urge reactivityReducing sleep deprivation in BPD may facilitate reductions in suicide, NSSI urges.

The Relationship of Lifestyle Risk Factors and Depression in Korean Adults: A Moderating Effect of Overall Nutritional Adequacy

Background: Little is known regarding the role of nutrition in determining the associations between lifestyle risk factors and depression. Objectives: This study examined whether or not nutritional adequacy modulates the relationship between depression and lifestyle risk factors in Korean adults aged 18-65 years (n = 7446). Methods: Data were obtained from the 2016 and 2018 Korea National Health and Examination Survey. Depression, smoking, at-risk alcohol consumption, physical inactivity, sleep deprivation, and mean adequacy ratio (MAR) were assessed. Results: Individuals with two (OR = 1.960, p < 0.001), three (OR = 4.237, p < 0.001), or four (OR = 5.312, p < 0.001) risk factors had a significantly higher risk of depression compared to individuals with one or zero risk factor. In contrast, individuals with moderate MAR (OR = 0.607, p < 0.001) and high (OR = 0.698, p < 0.001) MAR had a lower depression risk compared to individuals with low MAR. Moderation analysis showed a moderating effect of MAR (coefficient = −0.220, p = 0.007) on the relationship between risk factors and depression. Conclusions: The current findings suggest that overall nutritional adequacy plays a modulating role in determining the relationship between depression and lifestyle risk factors in Korean adults.