Nightmares and alexithymia in traumatized North Korean refugees.

BACKGROUND: The present study examined the association between nightmare distress and alexithymia in traumatized North Korean (NK) refugees resettled in South Korea and the effects of clinical or subclinical psychiatric symptoms on this association. METHODS: Thirty-eight NK refugees living in South Korea who had traumatic experiences (15 males, 23 females; 29.50 ± 13.11 years of age) were recruited. The Structured Clinical Interview for DSM-IV and the Clinician-Administered Post-Traumatic Stress Disorder (PTSD) Scale were conducted. All participants completed a series of questionnaires on the history of their previous traumatic experiences, the Beck Depression Inventory, the Nightmare Distress Questionnaire (NDQ), the Toronto Alexithymia Scale (TAS), and the Impact of Event Scale. In total, 18 refugees were classified as having nightmare distress based on NDQ scores, and 20 refugees were not. RESULTS: Refugees with nightmares reported significantly higher TAS total scores and Difficulty Identifying Feelings (DIF; a subscale of TAS) scores compared to those without nightmares. In addition, NDQ scores were positively correlated with TAS total scores (r = 0.43, p < 0.01) and DIF scores (r = 0.49, p < 0.01). These correlations remained significant after excluding refugees with current axis I psychiatric disorders or clinical or subclinical depressive symptoms. However, there was no significant correlation between nightmares and alexithymia after excluding refugees with clinical or subclinical trauma-related symptoms. CONCLUSIONS: Nightmares in traumatized refugees were associated with alexithymia even in the absence of current psychiatric disorders or depressive symptoms. Trauma-related symptoms might be a mediating factor between nightmares and alexithymia in traumatized refugees.

Polysomnographic Sleep and Attentional Deficits in Traumatized North Korean Refugees.

INTRODUCTION: Attentional deficits and sleep problems are common in refugees who have experienced trauma. In the present study, we used polysomnography (PSG) to investigate the relationship between attentional deficits and objective measures of sleep structure in traumatized North Korean refugees. METHODS: We recruited 32 North Korean refugees (mean age = 33.78 ± 14.33 years) and 39 South Korean participants (mean age = 35.03 ± 11.08 years). Sustained attention and divided attention were assessed using the Computerized Attention Test. We conducted an overnight PSG to objectively assess sleep structure. The participants also completed the Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Impact of Event Scale-Revised (IES-R), Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI), and Insomnia Severity Index (ISI). RESULTS: The North Korean refugees showed more commission errors (CEs, p < 0.05) and a larger standard deviation (SD) of the reaction time (RT) (p < 0.05) in the sustained attention task compared to the South Korean participants. Furthermore, the North Korean refugees showed a shorter period of wake after sleep onset (WASO, p < 0.01), less time spent in N1 (p < 0.05), and more time spent in N2 (p < 0.05). The larger SD of RT in the sustained attention task in the North Korean refugees was positively correlated with WASO (r = 0.62, p < 0.01) and N1 stage (r = 0.47, p < 0.05) after controlling for age, sex, BDI, BAI, and IES-R. CONCLUSION: The North Korean refugees showed poorer performance on the sustained attention task. Nocturnal PSG revealed shorter WASO and time spent in N1 in this population, which are independently associated with the preservation of attentional capacity. These data suggest that traumatized refugees may compensate for attentional deficits induced by their traumatic experiences via increased sleep continuity.