DELTA-SLEEP-INDUCING PEPTIDE IN NORMAL HUMANS AND IN PATIENTS WITH SLEEP-APNEA AND NARCOLEPSY

We measured morning plasma concentrations of delta sleep-inducing-pept ide-like-immunoreactivity (DSIP-LI) in 9 sleep apnea patients, 10 narc olepsy patients, and 11 normal controls. Comparisons between the three groups showed no significant differences, although there was a trend toward association with low levels of DSIP-LI in the narcoleptic group , particularly in patients not using medications. No differences were found in the morning or evening plasma DSIP-LI levels in a second grou p of 11 normal controls and 8 sleep apneics. Our findings do not appea r to support a biological marker role of disease activity for single m easures of plasma DSIP in sleep apnea.