Loneliness, sleep and daily stress: Evidence of direct and indirect effects.

This study investigated: i) the effects of loneliness on self-reported sleep outcomes and daily stress/hassles, ii) whether the effects of loneliness on sleep outcomes were mediated through prior-day stress/hassles and iii) if the effects of loneliness on daily stress/hassles were mediated through prior-night sleep measures. Using a 7-day diary design, this study aimed to investigate relationships between loneliness, daily sleep outcomes and daily stress/hassles. Participants (N = 174, M_age 19.95, 86.2% female) completed the UCLA Loneliness Scale once before a 7-day online diary twice per day. Measures of daily stress and hassles were completed before bed and sleep outcomes the following day. Multilevel modelling found higher levels of loneliness were associated with poorer sleep quality, greater pre-sleep arousal, morning tiredness, fewer total hours slept and higher levels of daily stress and hassles across the 7-day study. Loneliness was found also to have indirect effects on sleep quality, pre-sleep arousal and morning tiredness through prior-day daily stress and hassles. In addition, loneliness also had indirect effects on daily stress and hassles through prior night sleep measures. The current findings suggest that interventions aimed at mitigating the effects of loneliness should also incorporate components that target modifiable risk factors such as sleep and stress.