Table 2

Parent-reported sleep problems in relation to behavioural problems in 11-year-old children born extremely preterm† in Norway during 1999 and 2000

Difficulty falling asleep or frequent awakeningsSnoringDaytime sleepinessNot recommended sleep duration‡
SDQ scores No
(n=143) mean
Yes
(n=54) mean
Adjusted§
(n=195)
OR (95% CI)
No
(n=144) mean
Yes
(n=55) mean
Adjusted§
(n=197)
OR (95% CI)
No
(n=165) mean
Yes
(n=33) mean
Adjusted§
(n=196)
OR (95% CI)
No
(n=104) mean
Yes
(n=32) mean
Adjusted§
(n=135)
OR (95% CI)
Parent-reported
Emotional problems 2.2 3.8*** 1.4 (1.2 to 1.6) 2.4 3.2* 1.2 (1.0 to 1.3) 2.3 3.9*** 1.4 (1.1 to 1.6)2.43.31.2 (0.9 to 1.4)
Conduct problems 0.9 1.5* 1.3 (1.1 to 1.7) 1.0 1.4* 1.3 (1.0 to 1.6)1.01.51.3 (0.9 to 1.7)1.01.41.2 (0.9 to 1.6)
Hyperactivity/inattention problems 3.2 4.6** 1.2 (1.1 to 1.4)3.44.01.1 (0.9 to 1.2) 3.4 4.6* 1.2 (1.0 to 1.4)3.34.41.2 (0.9 to 1.3)
Peer problems 1.2 2.1** 1.3 (1.1 to 1.5)1.31.81.2 (0.9 to 1.4) 1.3 2.1* 1.2 (1.0 to 1.5)1.41.61.1 (0.9 to 1.4)
Total difficulties 7.6 11.9*** 1.1 (1.1 to 1.2) 8.0 10.4* 1.1 (1.0 to 1.1) 8.0 12.1*** 1.1 (1.1,1,2) 7.9 10.6* 1.1 (1.0 to 1.1)
Teacher-reported (n=169)(n=170)(n=170)(n=120)
Emotional problems 1.5 2.7** 1.2 (1.1 to 1.4)1.72.31.1 (0.9 to 1.3) 2.0 2.7** 1.3 (1.1 to 1.5)1.71.91.1 (0.9 to 1.3)
Conduct problems1.01.51.3 (0.9 to 1.7) 0.5 0.9* 1.4 (1.0 to 1.8)1.11.61.2 (0.9 to 1.6)0.50.71.3 (0.8 to 2.1)
Hyperactivity/inattention problems2.93.8 1.1 (1.0 to 1.3)2.93.8*1.1 (1.0 to 1.3)2.93.91.2 (0.9 to 1.3)3.23.41.0 (0.9 to 1.2)
Peer problems1.31.81.1 (0.9 to 1.3)1.22.0*1.2 (1.0 to 1.4)1.41.91.1 (0.9 to 1.4)1.72.11.1 (0.9 to 1.4)
Total difficulties 6.3 9.1** 1.1 (1.0 to 1.1) 6.2 9.0** 1.1 (1.0 to 1.1) 6.5 9.6* 1.1 (1.0 to 1.2)6.67.71.0 (0.9 to 1.1)
  • *p≤0.05, **p≤0.01, ***p≤0.001 (t-test). Boldface denotes significant group differences.

  • †Gestational age <28 weeks or birth weight <1000 g.

  • ‡Not recommended sleep duration at 11 years was defined as <9 hours.

  • §Logistic regression: adjusted for sex, single parenthood and maternal education (dichotomised as less than a 3-year college education or not).

  • SDQ, Strengths and Difficulties Questionnaire.