Table 3.

Multivariate ORs with 95% CIs for the association between cigarette smoking and risk of classic HL overall and by tumor EBV status in a comparison with NHL patient controls

NHL patients
Classic HL
NumberHL overall
EBV-positive lymphoma
EBV-negative lymphoma
NumberOR (95% CI)OR (95% CI)OR (95% CI)
Never smokers1,367299ReferenceReferenceReference
Ever smokers1,6282751.21 (0.95-1.54)1.87 (1.20-2.89)1.14 (0.84-1.54)
Phomogeneity*0.140.0050.41
    Former smokers950920.87 (0.64-1.20)1.11 (0.62-1.97)0.90 (0.60-1.33)
    Current smokers6731821.56 (1.18-2.08)2.75 (1.69-4.47)1.35 (0.95-1.92)
    Phomogeneity0.0010.00010.12
Age at initiation (y)
    ≤14116572.49 (1.55-4.00)3.34 (1.50-7.47)2.80 (1.58-4.97)
    15-19354911.36 (0.96-1.94)2.21 (1.19-4.11)1.18 (0.76-1.82)
    ≥20201331.33 (0.81-2.16)3.32 (1.65-6.69)0.81 (0.40-1.60)
    Ptrend0.050.800.001
Intensity (cigarettes/day)
    1-9124310.95 (0.54-1.68)1.46 (0.57-3.76)0.79 (0.40-1.57)
    10-193621031.82 (1.29-2.56)3.71 (2.08-6.62)1.52 (0.99-2.33)
    ≥20180461.60 (1.01-2.52)2.59 (1.21-5.56)1.51 (0.85-2.68)
    Ptrend0.960.800.68
Duration (y)
    ≤911341.50 (0.65-3.46)2.40 (0.75-7.67)1.36 (0.54-3.43)
    10-29102821.28 (0.84-1.95)1.99 (0.94-4.22)1.06 (0.65-1.74)
    ≥30558651.79 (1.25-2.58)3.58 (1.90-6.76)1.66 (1.02-2.71)
    Ptrend0.480.650.87
Cumulative exposure (cigarette years)
    ≤14946531.29 (0.73-2.25)1.32 (0.52-3.37)1.11 (0.59-2.07)
    150-29983421.31 (0.76-2.23)2.37 (0.94-5.97)1.08 (0.57-2.05)
    ≥300537851.75 (1.25-2.45)3.83 (2.15-6.80)1.58 (1.01-2.45)
    Ptrend0.530.710.66
Time since cessation (y)§
    1-497150.68 (0.33-1.43)0.53 (0.11-2.43)0.33 (0.12-0.96)
    5-9152240.91 (0.50-1.66)1.53 (0.56-4.13)1.10 (0.53-2.25)
    ≥10701540.91 (0.63-1.31)1.16 (0.59-2.27)1.04 (0.65-1.65)
    Ptrend0.320.440.62
  • NOTE: All analyses are adjusted for matching variables [age (in 10-y categories), sex, and country], number of younger and older siblings, history of infectious mononucleosis, country-specific measure of mother's age at subject's birth, mother's education, subjects' level of education, and familial history of hematopoietic cancer.

  • * Test for homogeneity of effect of smoking history (ever versus never).

  • Test for homogeneity of effect of smoking status (former, current, never).

  • Among current smokers only.

  • § Among former smokers only.