Sleep and paranoia: A systematic review and meta-analysis

Background
Sleep dysfunction commonly co-occurs with paranoia and is hypothesised to be a contributory causal mechanism in its development and maintenance.
Objectives
To systematically review and quantitatively evaluate the evidence for the relationship between sleep dysfunction and paranoia across the spectrum of severity.
Method
A systematic search was conducted to identify studies investigating the relationship between aspects of sleep and paranoia across clinical and non-clinical groups. A random effects model using a Fisher r-to-z transformed correlation coefficient was used for meta-analysis.
Results
45 studies were included in the review and 14 in the meta-analysis. The literature supports a small-to-moderate association (r = 0.30, 95 % CI: 0.16–0.40 for the seven studies using the most robust measures) with significant heterogeneity among studies but no evidence of publication bias. There is evidence that the relationship is to some extent causal, with sleep disruption leading to increased paranoia, though there is also some evidence of a bi-directional relationship. Negative affect is frequently seen as a mediator of this relationship.
Conclusion
This review for the first time examines the significant relationship between sleep and paranoia individually. Studies are needed that further assess the potential for early intervention of sleep dysfunction in those experiencing paranoia.