Table 4.

Associations between cumulative shift work and 6-sulfatoxymelatonin mesor and acrophase, stratified by shift work status and time of day

Cosinor parameters
Mesor (95% CI)Acrophase (95% CI)
NMean change per year (%)aAdjusted mean change per year (%)a,bMean difference per year (h)aAdjusted mean difference per year (h)a,b
Day (only)147−0.5 (−1.6, 0.7)0.3 (−1.0, 1.5)−0.01 (−0.04, 0.01)−0.01 (−0.04, 0.01)
Day (rotation)114−1.0 (−2.0, 0.09)0.4 (−1.4, 2.2)−0.001 (−0.02, 0.02)0.02 (−0.02, 0.06)
Night (rotation)114−1.1 (−2.3, 0.2)−0.09 (−2.4, 2.2)0.01 (−0.02, 0.05)0.004 (−0.06, 0.07)
  • aAll estimates were not significant (P > 0.05).

  • bAdjusted models controlled for age, education, parity, age of first birth, and use of sleep aid.