The purpose of this study was to describe the circadian rhythm of abdominal skin temperature and explore factors related to the timing of circadian rhythmacr ophase. Thirty-four preterminfants (gestational age 26 to 33 weeks) were studied in the home environment at 44 to 46 weeks postconceptional age. Insulated abdominal skin was monitored continuously, and parents recorded sleep/wake activity over a 24-h period. Circadian rhythmwas analyzed using cosinor analysis. Using MANCOVA, the effects of cosleeping, feeding method, night feeding, hospital stay, time home, and illness on acrophase were determined. Infants demonstrated evidence of developing circadian rhythm of temperature. Cosleeping and length of hospital stay were significantly related to acrophase. The mean acrophase for cosleeping infants was 07:44 (95% confidence interval = 05:12, 11:08), whereas that for non- cosleeping infants was 22.05 (95% confidence interval = 17:31, 01:42). Proximity with
parents during nighttime hours may serve to entrain preterminfant circadian rhythm. |