The value of sleep recording in evaluating somnambulism in young adults

Somnambulism (SOM) is a benign childhood sleep disorder which may persist until young adulthood. The diagnosis relies heavily on the history, and no polysomnographic (PSG) criteria have yet been defined. The present study attempts to evaluate the role of whole-night polysomnographic recording in the investigation of SOM. The PSG records of 24 sleepwalkers, 18-25 years old, and 12 age-matched controls, were analysed. Sleepwalkers had remarkably more epochs containing hypersynchronous delta waves (HSD) (59.6 +/- 60.1 vs. 1.7 +/- 3.2; P less than 0.0001), a higher proportion of HSD/total time spent in stage 3-4 (24.9 +/- 21.1% vs. 1.1 +/- 2.0%, P less than 0.0002), and more stage 3-4 sleep interruptions (8.4 +/- 5.7 vs. 3.7 +/- 1.7, P less than 0.004). They also tended to have a larger proportion of their sleep time in stage 3-4 (30.6 +/- 11.7% vs. 22.6 +/- 6.8%; P less than 0.07). Although their sensitivity and specificity have yet to be more fully investigated, these seem to be quantitative, easy-to-use variables which may characterize adult SOM and may aid in its proper diagnosis.