ORIGINAL ARTICLE
Factors differentiating infants identified by parents as
problem sleepers, and those that are not
Rosemary GIBSON,
1
Philippa GANDER
1
and Dawn ELDER
2
1
Sleep/Wake Research Centre, Massey University, and
2
Paediatrics and Child Health, University of Otago,
Wellington, New Zealand
Abstract
Sleep problems are common during infancy. Possible factors which contribute to parental perception
of problem sleep were investigated as part of a pilot study collecting objective data on the sleep of
1-year-old New Zealand infants (n = 52 families). Sleep of each infant was monitored for a week at
home (ankle actigraphy and sleep diaries, which also included daily infant mood ratings) and parents
completed questionnaires addressing their infant’s sleep, the living and sleeping environment, and
feeding. Thirty-five percent of the infants were considered by parents to have a sleeping problem.
These infants had shorter night-time sleep as measured by actigraphy (median = 10.0 h vs 10.7 h for
non-problem sleepers [U = 193.0, P < 0.05]), less total sleep per 24 h (median = 11.4 h vs 12.5 h [U
= 169.5, P < 0.01]), and were put to bed more often per 24 h (median = 3.5 times vs 3.0 times [U =
201.5, P < 0.05]). Problem sleepers were also more likely to spend 20 min awake at night (68% vs
32% [c
2
= 16.78, P < 0.001]), as well as currently being breastfed (55% vs 45% [c
2
= 5.97, P < 0.05]),
and to have moderate–bad mood at bedtime (59% vs 41% [c
2
= 6.54, P < 0.05]). Sleep was also related
to parent’s diary ratings of their infant’s mood and temperament. This study highlights factors
contributing to parental perception of problem sleep which is vital for recognizing and managing
such problems throughout infancy.
Key words: actigraphy, breastfeeding, infancy, mood, sleep.
INTRODUCTION
Sleep problems varying in nature and intensity are
reported in approximately one-third of infants from 6 to
36 months of age.
1,2
Sleep problems are one of the
leading reasons that parents consult with a pediatrician.
3
However, a survey in 2001 revealed that only 46% of a
sample of pediatricians were confident in screening for
sleep problems, despite acknowledging their impor-
tance to health and daytime performance.
4
Past studies have highlighted many factors that can
contribute to problematic sleep during infancy. Such
factors can be intrinsic or extrinsic and include infant
health, parenting style, and sleep rituals.
5,6
Infant mood
and temperament have also been highlighted as having
an effect on sleep quality and timing,
7,8
which may in
turn influence parents’ perception of their child having
sleep problems.
The aims of the present study were to pilot methods
for obtaining actigraphic sleep data from one-year-old
infants in their own homes and to test the following
hypotheses: (i) that infants indentified as problem sleep-
ers by their parents also have poorer sleep as indicated
by objective measures; (ii) that poor sleep (identified by
parents in a retrospective questionnaire) is related to
poorer mood and temperament as indicated by daily
Correspondence: Ms Rosemary Gibson, Sleep/Wake
Research Centre, Massey University, Private Bag 756,
Wellington, New Zealand. Email: r.gibson@massey.ac.nz
Accepted 11 August 2011.
Sleep and Biological Rhythms 2012; 10: 46–52 doi:10.1111/j.1479-8425.2011.00517.x
46 © 2011 The Authors
Sleep and Biological Rhythms © 2011 Japanese Society of Sleep Research