Table 1 Characteristics of the study population
CharacteristicCasesControlsχ2
No (%)No (%)p Value
All subjects16091972
Age*64.9 (9.8)65.0 (10.2)0.77
Sex
    Male901 (56.0)1043 (52.9)
    Female708 (44.0)929 (47.1)0.06
Race/ethnicity
    White, non-Hispanic1470 (91.4)1835 (93.1)
    Hispanic62 (3.8)79 (4.0)
    Black74 (4.6)56 (2.8)
    Other3 (0.2)2 (0.1)0.02
Postmenopausal hormone use
    No470 (75.6)551 (69.5)
    Yes144 (23.5)242 (30.5)0.003
Western diet†
    Low risk401 (24.9)668 (33.9)
    Intermediate risk556 (34.6)652 (33.1)
    High risk652 (40.5)652 (33.1)<0.001
Number of cigarettes smoked regularly
    Never661 (41.3)925 (47.0)
    ⩽20/day643 (40.2)773 (39.3)
    >20/day297 (18.6)269 (13.7)<0.001
Study centre
    Northern California777 (48.3)819 (41.5)
    Minnesota579 (36.0)805 (40.8)
    Utah253 (15.7)348 (17.6)<0.001
Microsatellite instability
    MSI-positive193 (15.9)
    MSI-negative1018 (84.1)
MLH1 -93G>A
    GG958 (59.6)1173 (59.6)
    GA555 (34.5)689 (35.0)
    AA95 (5.9)106 (5.4)0.78
MLH1 Ile219Val
    Ile/Ile767 (47.7)939 (47.6)
    Ile/Val682 (42.4)846 (42.9)
    Val/Val160 (9.9)187 (9.5)0.88
MLH1 -93G>A/Ile219Val
    GG and Ile/Ile354 (22.0)411 (20.9)
    GA and Ile/Ile318 (19.8)421 (21.4)
    GG and Ile/Val444 (27.6)576 (29.3)
    GA and Ile/Val237 (14.7)267 (13.6)
    AA and Ile/Ile95 (5.9)106 (5.4)
    GG and Val/Val160 (10.0)187 (9.5)0.55
MSH6 Gly39Glu
    Gly/Gly1042 (64.8)1343 (68.4)
    Gly/Glu517 (32.2)559 (28.5)
    Glu/Glu48 (3.0)62 (3.2)0.06
  • *Mean (SD and t test).

  • †Based on lower (low risk), middle (intermediate risk) and upper tertiles (high risk) of Western dietary pattern scores for control subjects; see Materials and methods section.