Association between sleep paralysis and anxiety: a systematic review and meta-analysis.

PURPOSE: Sleep paralysis is a REM-sleep parasomnia which manifests as a temporary inability to perform voluntary muscle movements during the sleep-wake transition. Anxiety disorders are characterized by excessive fear, anxiety, and related behavioral disturbances. Notably, lifetime prevalence of sleep paralysis is elevated among psychiatric populations. The purpose of this review and meta-analysis was to evaluate the association between sleep paralysis and anxiety, encompassing both anxiety symptoms and formally diagnosed anxiety disorders. METHODS: This systematic review and meta-analysis followed PRISMA and Cochrane guidelines and was registered in PROSPERO (CRD42024579831). PubMed, Embase, and Cochrane Library were searched. Risk ratios (RR) and standardized mean differences (SMD) were pooled using random-effects models estimated with restricted maximum likelihood (REML). Heterogeneity was quantified using I2. Subgroup and leave-one-out sensitivity analyses were performed. Publication bias was evaluated using funnel plots and Egger's test. Statistical analysis was conducted using R (version 4.4.1) with the metafor package. RESULTS: Eleven eligible studies involving 5568 participants were included. Sleep paralysis was associated with significantly higher anxiety scores compared to controls (SMD 0.35; 95% CI 0.27-0.44; p < 0.01) with zero heterogeneity (I2 = 0.0%). Publication bias was low. In a different analysis, meta-analysis showed no significant difference in anxiety prevalence (RR 1.28; 95% CI 0.59-2.77; p = 0.53); sensitivity analysis excluding one outlier demonstrated a significant risk (RR 1.80; 95% CI 1.08-2.99). CONCLUSION: Sleep paralysis appears to be associated with elevated anxiety levels and may occur more frequently among individuals with anxiety-related conditions.