1106 SUBJECTIVE AND OBJECTIVE SLEEP QUALITY INDICATORS AND THE RELATIONSHIP TO POSTPARTUM DEPRESSION

Abstract

Introduction: Relationships between subjective, but not objective sleep outcomes, and postpartum depression have been observed in small, cross-sectional samples. The purpose of this study was to examine these relationships using a large sample followed prospectively from birth through 6 and 12 weeks postpartum. Methods: Data from a RCT of a behavioural sleep intervention with 217 first-time mothers were subjected to secondary analysis. Objective sleep variables (nocturnal sleep, night awakenings, daytime sleep) were measured by actigraphy at 6 and 12 weeks. Subjective sleep quality was measured by the General Sleep Disturbance Scale (GSDS) and mothers' reports of their sleep as a “small”, “big” or “no” problem. Depressive symptoms were measured with the Edinburgh Postnatal Depression Scale (EPDS). Control variables included group allocation, baseline EPDS and social support. Logistic regression was used to estimate the association between subjective and objective sleep variables and the presence of postpartum depression. Separate models estimated the odds of postpartum depression according to each sleep variable. Results: GSDS scores at baseline were not related to depression; however, GSDS scores at 6 weeks were associated with >3 times the odds of depression (OR=3.56; 95% CI=1.73-7.33). The perception that sleep was a “small” or “big” problem at 6 weeks was associated with >3 (OR=3.40; 95% CI=1.54-7.46) and >8 (OR=8.29; 95% CI=2.41-28.59) times the odds of depression, respectively. There was no association between any objective sleep measures and postpartum depression. Conclusion: Subjective sleep quality indicators are strongly associated with postpartum depression while objective sleep outcomes are not. Sleep complaints may be an important clinical indicator of low mood. Future intervention studies to improve mood in the postpartum could target women's expectations and appraisal of their sleep via cognitive- behavioural strategies.