Table 2.

ORs with 95% CIs for the association of selected factors with risk of HL overall and EBV-negative and EBV-positive tumor in younger and older adults and for all ages combined

Relative risk of HL by selected exposures
18–44 yrs45–74 yrsAll ages
Cases versus controlsEBVpositive versus EBVnegativeCases versus controlsEBVpositive versus EBVnegativeCases versus controlsEBVpositive versus EBVnegative
IM (yes versus no)
    HL overall1.97 (1.29–3.01)2.68 (1.40–5.12)1.48 (0.65–3.35)0.58 (0.05–6.35)1.84 (1.27–2.66)2.32 (1.25–4.31)
    EBV-negative1.36 (0.81–2.26)1.31 (0.46–3.77)1.35 (0.86–2.14)
    EBV-positive3.96 (2.19–7.18)0.96 (0.13–7.28)3.23 (1.89–5.55)
Number of older siblings (trend per sibling)
    HL overall1.03 (0.88–1.22)0.65 (0.45–0.95)1.02 (0.88–1.16)1.60 (1.12–2.29)1.03 (0.93–1.14)1.06 (0.83–1.35)
    EBV-negative1.01 (0.83–1.22)0.84 (0.68–1.03)0.93 (0.81–1.07)
    EBV-positive0.77 (0.56–1.05)1.35 (1.06–1.70)1.11 (0.92–1.33)
Number of younger siblings (trend per sibling)
    HL overall0.94 (0.78–1.13)0.52 (0.33–0.80)1.03 (0.90–1.19)0.81 (0.53–1.22)0.99 (0.89–1.11)0.73 (0.55–0.96)
    EBV-negative1.02 (0.83–1.26)1.08 (0.89–1.32)1.04 (0.90–1.20)
    EBV-positive0.58 (0.39–0.86)0.85 (0.65–1.11)0.78 (0.63–0.97)
Persons per room in household (trend per person)
    HL overall1.03 (0.90–1.17)0.93 (0.71–1.23)1.00 (0.91–1.09)1.08 (0.85–1.36)1.01 (0.94–1.09)1.05 (0.89–1.24)
    EBV-negative0.98 (0.84–1.15)0.96 (0.84–1.09)0.97 (0.88–1.07)
    EBV-positive0.99 (0.77–1.26)1.06 (0.92–1.22)1.06 (0.94–1.20)
Kindergarten (yes versus no)
    HL overall0.78 (0.56–1.09)1.85 (0.95–3.58)0.93 (0.57–1.49)1.34 (0.36–5.05)0.82 (0.63–1.08)1.61 (0.91–2.86)
    EBV-negative0.71 (0.49–1.03)0.87 (0.46–1.62)0.75 (0.54–1.03)
    EBV-positive1.09 (0.61–1.96)0.95 (0.39–2.34)1.04 (0.65–1.69)
Mother's age at subject's birth (trend per year)
    HL overall1.01 (0.98–1.03)0.99 (0.94–1.05)0.99 (0.96–1.02)1.09 (1.03–1.17)1.00 (0.98–1.02)1.03 (0.99–1.07)
    EBV-negative1.00 (0.97–1.03)0.94 (0.91–0.98)0.98 (0.96–1.00)
    EBV-positive1.00 (0.95–1.05)1.05 (1.01–1.10)1.03 (0.99–1.06)
Paternal education *
    HL overall1.05 (0.84–1.32)1.12 (0.74–1.71)1.18 (0.87–1.60)0.59 (0.25–1.36)1.09 (0.91–1.30)0.96 (0.67–1.40)
    EBV-negative HL1.01 (0.78–1.31)1.27 (0.85–1.90)1.08 (0.87–1.34)
    EBV-positive HL1.00 (0.67–1.48)0.91 (0.51–1.63)0.95 (0.69–1.30)
Subject education *
    HL overall0.86 (0.66–1.12)0.85 (0.51–1.39)0.97 (0.78–1.22)0.96 (0.55–1.70)0.92 (0.77–1.08)0.89 (0.62–1.30)
    EBV-negative0.92 (0.68–1.25)0.99 (0.73–1.35)0.95 (0.77–1.19)
    EBV-positive0.84 (0.51–1.37)0.92 (0.62–1.37)0.87 (0.64–1.18)
Maternal education (Sweden) *
    HL overall1.36 (1.07–1.73)0.94 (0.58–1.52)1.17 (0.76–1.81)0.61 (0.21–1.71)1.31 (1.07–1.61)0.86 (0.56–1.32)
    EBV-negative HL1.56 (1.18–2.05)1.44 (0.86–2.42)1.53 (1.20–1.95)
    EBV-positive HL1.33 (0.86–2.06)0.99 (0.42–2.34)1.23 (0.85–1.80)
Maternal education (Denmark) *
    HL overall0.76 (0.54–1.05)0.78 (0.43–1.43)0.93 (0.60–1.44)1.22 (0.43–3.43)0.80 (0.62–1.05)0.85 (0.51–1.41)
    EBV-negative HL0.83 (0.58–1.19)0.98 (0.55–1.73)0.87 (0.64–1.18)
    EBV-positive HL0.68 (0.39–1.19)1.41 (0.68–2.95)0.85 (0.53–1.34)
  • NOTE: Analyses are adjusted for matching variables (age, gender, and country) besides history of IM and country-specific measures of maternal education. Analyses of older and younger siblings are mutually adjusted.

  • * Trend across educational categories <10, 10–12, and ≥13 yrs.