Sleep-related erections in vegetative state patients

Study objectives: To determine whether sleep-related erections occur in veg etative state and if so, to investigate their relationship with rapid eye m ovement (REM) sleep. Design: N/A Setting: Major rehabilitation hospital. Patients: Nine male patients in vegetative state aged 17-40 years. Interventions: Continuous 24-hour polysomnographic recordings including pen ile circumferencial changes. Measurements and Results: Sleep-related erection episodes (SREe's) were not ed in all nine patients, ranging in number from 1-7/24 hr (average 4.4+2.4) and lasting 6 to 50 min (average 22.0+5.7 min). The number of REM periods (REMp's) ranged from 4-11 (average 6.6+2.5) and lasted for 1.0 to 44.0 min (average 16.0+6.6 min). Ninety-five percent of the SREe's recorded were ass ociated with REMp's, usually (76.3%) appearing simultaneously with the REMp or soon thereafter; 64.6% of the REMp's were associated with SRE's. For bo th the nocturnal and diurnal periods, there were more REMp's with SREe's th an without, and the REMp's associated with SREe's were of longer duration ( by 25.5% and 28.4%, respectively). There were no statistically significant differences for any of the REMp or SREe parameters between the recovered an d nonrecovered patients. Conclusions: The sleep-related erection characteristics of patients in vege tative state are similar to those of normal individuals. These findings may have implications for the assessment of the reorganization of REM sleep du ring recovery from vegetative state and may further help in our understandi ng of the pathophysiology of vegetative state. More studies are needed in l arger groups of patients.