Developmental Course of Nighttime Sleep-Wake Patterns in Full-Term and Premature Infants During the First Year of Life. I.

Abstract

Summary: Two groups of infants (40 normal full-term, 24 prematurely born infants) were matched on conceptional age and were studied at seven ages during the first year of life, All-night time-lapse video somnography was obtained in the home at 2, 4, 8, 20, 24, 36, and 52 weeks of age. The developmental course of sleep-wake state proportions, sleep onset indices, and special variables assessing temporal organization are compared. Age-appropriate developmental norms for sleep-wake state assessment during the first year of life are presented, using video somnography. In general, sleep-wake state ontogenesis is comparable in the two groups. The premature group is more variable from one age to the next, even though both groups demonstrate significant individual stability of some sleepwake variables over the first year of life. Key Words: Sleep-wake state-Gestational age-Active sleep-Quiet sleep.Sleep difficulties in infants from birth to 3 years have become one of the most common problems of pediatric practice. Usually the disturbances are short -lived and probably without long-term consequences, although sleep habits of young infants may reflect longer lasting temperamental characteristics or aspects of dyadic interaction that herald later childhood and adult sleep patterns. Given the prevalence of the problem in the pediatric age group, it is surprising how little longitudinal data exist describing the ontogenesis of sleep-wake patterns in normal infants.Cross-sectional studies during infancy and childhood have repeatedly confirmed that developmental changes of REM sleep, NREM sleep, and waking do occur (1)(2)(3)(4)(5)(6)(7)(8)(9). The studies confirm that, by and large, the REM state predominates in immature infants and declines during maturation, sleep onsets from wakefulness are to the REM state during the early months of life and to the NREM state later, diurnal influences on REM/NREM organization during the night emerge gradually, and poor epoch-by-epoch coordination of physiological systems results in immature sleep state organization (indeterminate states) in

Infant Arousals During Mother-Infant Bed Sharing: Implications for Infant Sleep and Sudden Infant Death Syndrome Research

“…The peak age for SIDS corresponds to a developmental stage when infant sleep in the solitary environment is undergoing consolidation, the amount of quiet sleep is increasing, and sustained bouts of quiet sleep are lengthening. 7,8,10,[17][18][19][20][21][22] Many SIDS researchers believe that arousal deficiency plays an important role in the etiology of SIDS (see beginning of article). If this is true, then manipulations or conditions that facilitate arousability might be protective against SIDS.…”

“…Sleep gradually consolidates over the first 6 months of postnatal life, as shown by lengthening of sustained sleep bouts. 8,[17][18][19][20] Also, the total duration of quiet sleep (associated with high-voltage slow-wave electroenchephalogram [EEG] or delta) increases and episodes of quiet sleep lengthen progressively. 7,10,18,21,22 The amount of rapid eye movement (REM) sleep and indeterminate sleep, by contrast, declines or remains stable.…”

“…8,[17][18][19][20] Also, the total duration of quiet sleep (associated with high-voltage slow-wave electroenchephalogram [EEG] or delta) increases and episodes of quiet sleep lengthen progressively. 7,10,18,21,22 The amount of rapid eye movement (REM) sleep and indeterminate sleep, by contrast, declines or remains stable. 10,21,22 Arguably, this selective increase in quiet sleep might undermine infant arousability because arousal threshold has been shown to be high in the EEG delta range in human infants and adults as well as in rats.…”

A Comparison of the Sleep?Wake Patterns of Cosleeping and Solitary-Sleeping Infants

“…The mean maternal age for the cosleeping group was 29.3 years (range 18-36), while the mean maternal age for the solitary-sleeping group was 29.1 years (range [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Five of the cosleeping families (62.5%) were middle-upper class, whereas six of the solitary-sleeping families (66.7%) were middle-upper class.…”

Developmental Care Does Not Alter Sleep and Development of Premature Infants

“…Conventionally, an infant is developmentally matured and settled at night when (s)he sleeps without waking during the hours from 12 midnight to 5 am, usually the time when parents are asleep. To measure this we have calculated, according to Anders and Keener, 12 the percentage longest sleep period (%LSP) (ie, number of minutes of sleep divided by 300 multiplied by 100). Another important developmental change in the organization of sleep-wake patterns is the appearance of diurnal (or circadian) rhythms.…”