Table 3.

Multivariable analysis of CIS in relation to HPV-16 status at first smear, stratified by smoking status

VariableNonsmokers*
Current smokers
Pinteraction
Cases/controlsOR (95% CI)Cases/controlsOR (95% CI)
HPV-16 status
    Negative96/169Reference172/177Reference0.12
    Positive35/125.6 (2.7-11.5)72/514.4 (5.6-36.8)
HPV-16 load
    Negative96/169Reference172/177Reference0.21
    Low12/55.1 (1.7-15.4)19/36.0 (1.7-20.8)
    High23/75.9 (2.4-14.6)53/227.0 (6.5-114.2)
    PtrendP < 0.0001P < 0.0001
  • * Nonsmokers, subject never smoked or smoked >2 years before the smear date.

  • Current smokers, subject smoked within 2 years before the smear date.

  • ORs adjusted for age at first smear, number of years between date of smear and diagnosis, current oral contraceptive use, and parity as categorized in Table 1. Number of sex partners before first smear was included as a continuous variable.