INFANT SLEEP ARCHITECTURE DURING BEDSHARING AND POSSIBLE IMPLICATIONSFOR SIDS

Arousal is an important protective response during sleep, and arousal deficit is hypothesized to play a role in the etiology of sudden infan t death syndrome (SIDS). Because environmental or caretaking factors h ave been shown to exert powerful effects on susceptibility to SIDS, ma nipulations that facilitate arousability might be protective against S IDS. All-night laboratory polysomnographic recordings were performed i n 20 routinely bedsharing and 15 routinely solitary sleeping healthy b reast-feeding Latino infants within the peak age range for SIDS, in bo th bedsharing (with mother) and solitary sleeping environments. The mo st important findings revealed by repeated measures analyses of varian ce were a significant reduction in stage 3/4 sleep and an inverse incr ease in stage 1/2 sleep on the bedsharing night compared to the solita ry night, irrespective of routine sleeping arrangement. Shorter mean d uration episodes of stage 3/4 sleep and longer mean stage 1/2 sleep ep isodes accounted for these differences. Because the arousal threshold is high in the electroencephalographic delta range, by limiting the am ount of stage 3/4 sleep, bedsharing should promote infant arousability and might be protective against SIDS. The results also suggest that a ccepted normative values for infant sleep established in solitary slee ping infants may not be representative of infants rai sed in social sl eeping environments.