Resilience Moderates the Association of Sleep Disturbance and Sleep Reactivity with Depressive Symptoms in Adult Volunteers

Purpose: Depression poses a substantial burden worldwide. Therefore, elucidating the pathophysiological mechanism of depression is important. Sleep disturbance and sleep reactivity are symptoms of depression and are also known to exacerbate depressive symptoms. On the other hand, it is well known that resilience ameliorates depressive symptoms. To our knowledge, there have been no reports to date regarding the interaction effects among sleep disturbance, sleep reactivity, and resilience on depressive symptoms. We hypothesized that resilience buffers the aggravating effects of sleep disturbance and sleep reactivity on depressive symptoms. To test this hypothesis, we conducted hierarchical multiple regression analyses. Subjects and Methods: A total of 584 Japanese adult volunteers were recruited between April 2017 and April 2018 by convenience sampling. Their demographic characteristics, sleep disturbance, sleep reactivity, resilience, and depressive symptoms were investigated using self-administered questionnaires. The data were analyzed using hierarchical multiple regression analyses. Results: Sleep disturbance and sleep reactivity were significantly positively associated with depressive symptoms, whereas resilience was significantly negatively associated with depressive symptoms. Moreover, there was a significant interaction between sleep disturbance or sleep reactivity and resilience on depressive symptoms. Resilience significantly alleviated the aggravating effect of sleep disturbance and sleep reactivity on depressive symptoms. Conclusion: Our results indicate that people with lower resilience have more severe depressive symptoms that are associated with sleep disturbance and sleep reactivity. Therefore, there is a possibility that the enhancement of resilience will buffer the aggravating effects of sleep disturbance and sleep reactivity on depressive symptoms, and that improving sleep quality might alleviate the negative effect of low resilience on depressive symptoms.