Rates of isolated sleep paralysis in outpatients with anxiety disorders.

Initial research suggests that rates of isolated sleep paralysis (ISP) are elevated in individuals with panic disorder and particularly low in individuals with other anxiety disorders. To further evaluate these findings, we examined rates of ISP in a sample outpatients with primary diagnoses of panic disorder (n=24), social anxiety disorder (n=18), or generalized anxiety disorder (n=18). We obtained an overall rate of ISP of 19.7%; rates for patients with panic disorder (20.8%) fell between those with generalized anxiety disorder (15.8%) and social phobia (22.2%). Analysis of comorbidities failed to provide evidence of link between depressive disorders and ISP, but did indicate a significant association between anxiety comorbidity and higher rates of ISP. Results are discussed relative to other variables predicting variability in the occurrence of ISP.