Isolated sleep paralysis (ISP) results from persistence of REM activity, including typical paralysis associated with REM, after an individual begins to awaken and become aware or as they are falling asleep.
During these episodes, individuals are aware of their surroundings, but are unable to move. Hallucinations, such as sensing presence of others, feeling external pressure on the chest, and hearing footsteps or odd sounds commonly accompany the paralysis. These experiences may cause fear and be interpreted as a supernatural experience in a culturally-distinct manner. Rates of isolated sleep paralysis (ISP) are elevated in individuals with panic disorder and particularly low in individuals with other anxiety disorders.
A recent study, to be published in the Journal of Anxiety Disorders
(available online 11 August 2005) examines the rates of ISP in outpatients with panic disorder relative to other anxiety groups, with particular attention to differences in rates among the anxiety disorders and the potential relationship of anxiolytic use to these rates.
Overall, a near 20% rate of ISP was obtained in this sample of outpatients seeking treatment for anxiety disorders, with no significant difference in rates among patients with a primary diagnosis of panic disorder, social anxiety disorder, or GAD. This study provides a much more reliable estimate of the rate of ISP in an anxiety-disordered population.
Although rates of ISP were significantly higher for patients with anxiety comorbidity, these results did not support an independent association between antidepressant/anxiolytic use and ISP.
This study was unique in examining anxiolytic use in a sample of outpatients with anxiety disorders, allowing for clarification of the predictive significance of medication use over and above the effect of having an anxiety disorder.
The authors stress that given the prevalence of ISP within anxiety samples, assessment of ISP symptoms as part of regular clinical practice may benefit patients by normalizing these often - frightening experiences.
Medindia on Sleep disorders:
Sleep disorders are of different kinds and the reason behind each disorder varies. This may include difficulty falling or staying asleep, falling asleep at inappropriate times, excessive total sleep time or abnormal behaviors associated with sleep.