Table 1.

Baseline characteristics of participants stratified by case-control status

CharacteristicMeasureCases (n = 1,461)Controls (n = 1,507)P*
AgeMean (SD)62.5 (5.1)62.3 (5.1)0.2
Ethnicity (white)98.5%98.7%0.3
BMI (kg/m2)Mean (SD)27.9 (3.7)28.2 (4.1)0.1
Tobacco useCurrent smoker20.2%17.3%0.1
Ever smoked63.3%65.5%0.3
Alcohol consumption in the past 12 moAlmost daily or more often38.5%37.8%0.5
Once or twice per week41.2%42.4%
Once or twice per month8.5%6.9%
Special occasions or never11.9%12.9%
Vitamin supplement use in past 12 mo (yes/no)7.8%7.9%0.9
Circulating vitamin and metabolite concentrationsMedian (5th-95th percentile) CasesMedian (5th-95th percentile) ControlsP*
Folate (nmol/L)15.9 (6.1-51.4)15.8 (6.2-52.3)0.6
Vitamin B12 (pmol/L)307 (156-542)299 (158-521)0.1
Holo-haptocorrin (pmol/L)247 (119-439)240 (120-425)0.04
Holo-transcobalamin (pmol/L)57 (23-117)56 (24-119)0.9
Total transcobalamin (pmol/L)860 (612-1,269)874 (602-1,270)0.1
tHcy (μmol/L)11.1 (7.8-17.6)11.1 (7.7-17.7)0.9
  • 2 test (proportions), Student's t test (means), or two-sample Wilcoxon rank-sum (Mann-Whitney) test (medians).

  • Numbers of cases and controls for whom these data were available: BMI (1,183 cases and 1,105 controls), current smoker (846 cases and 808 controls), ever smoked (1,208 cases and 1,117 controls), alcohol consumption (1,204 cases and 1,116 controls), and vitamin supplementation (875 cases and 831 controls).