Interpersonal Distress Is Associated with Sleep and Arousal in Insomnia and Good Sleepers

OBJECTIVE: The interpersonal environment is strongly linked to sleep. However, little is known about interpersonal distress and its association with sleep. We examined the associations among interpersonal distress, objective and subjective sleep in people with and without insomnia. METHODS: Participants in this cross-sectional observational study included men and women with insomnia (n = 28) and good sleeper controls (n = 38). Interpersonal distress was measured with the Inventory of Interpersonal Problems. Sleep parameters included insomnia severity, self-reported presleep arousal, and sleep quality; and polysomnographically-assessed sleep latency (SL), total sleep time (TST), wake after sleep onset (WASO), percent delta (stage 3 + 4 NREM), percent REM, and EEG beta power. Hierarchical linear regression was used to assess the relationship between distress from interpersonal problems and sleep and the extent to which relationships differed among insomnia patients and controls. RESULTS: More interpersonal distress was associated with more self-reported arousal and higher percentage of REM. More interpersonal distress was associated with greater insomnia severity and more cognitive presleep arousal for individuals with insomnia, but not for controls. Contrary to expectations, interpersonal distress was associated with shorter sleep latency in the insomnia group. Results were attenuated, but still significant, after adjusting for depression symptoms. CONCLUSION: Distress from interpersonal problems is associated with greater self-reported arousal and higher percent REM. Individuals with insomnia who report more distress from interpersonal problems have greater insomnia severity and cognitive presleep arousal, perhaps due to rumination. These findings extend our knowledge of the association between interpersonal stressors and sleep. Assessment and consideration of interpersonal distress could provide a novel target for insomnia treatment.