0648 Decreased Slow-Wave Sleep May Exacerbate Anxiety in Individuals with Low Anxiety

Abstract

Introduction Evidence suggests that individuals with generalized anxiety disorder exhibit decreases in slow-wave sleep (SWS). Because SWS has been shown to be modifiable, it is imperative to better understand the relationship between symptoms of anxiety and amount of SWS to inform treatment development. This study aimed to explore the relationship between anxiety and SWS, and to investigate the impact of slow-wave sleep disruption on state anxiety. Methods Twenty-seven participants’ (mean age 30.9) were recruited as part of an ongoing study examining the relationship between SWS and depression. Participants spent two nights in the laboratory: baseline (BL) and slow-wave disruption (SWD), where SWS was disrupted using auditory stimulation. Anxiety was measured using the State-Trait Anxiety Inventory (STAI). Both trait and state anxiety (BL, SWD) measures were collected. Repeated measures ANOVA was used to determine the impact of SWD on state anxiety. Results Participants’ trait anxiety scores were significantly correlated with percent N3, such that greater anxiety was associated with less N3 (r = -0.43; p<0.05). Individuals were then categorized as either high-anxiety (HA) or low-anxiety (LA) by median split (M=46.5). Results of the repeated measures showed a significant main effect of group (F=43.963; p<0.001), with HA individuals showing greater state anxiety than LA individuals. A significant interaction of group*condition was also found (F(1,24)=4.703; p=0.40). LA participants showed a significant increase in state anxiety following SWD (t=-2.539; p=0.028), while HA participants showed no change. Conclusion The current findings replicate previous research showing that anxious individuals have a reduced amount of SWS and demonstrate that decreases in SWS may exacerbate anxiety in individuals with low anxiety. Further, this work suggests that individuals with high anxiety may be more resilient to changes in anxiety state than individuals with low anxiety when SWS is reduced. Support (If Any) Goldschmied: K23MH118580 (NIMH)