Table 1

Characteristicsa of distal colorectal adenoma cases (326) and matched controls (326) nested in the Nurses’ Health Study, 1989–1996

CaseControlPb
Plasma 1,25(OH)2D in 1989–1991 (pg/ml)
Mean± SD31.6 ± 8.432.2 ± 8.60.3c
Median31.131.4
90th percentile42.642.4
10th percentile21.421.6
<26.0 pg/ml (%)27.621.20.03
Plasma 25(OH)D in 1989–1991 (ng/ml)
Mean± SD26.4 ± 10.626.8 ± 10.20.7c
Median25.325.6
90th percentile40.139.5
10th percentile13.914.9
Plasma 1,25(OH)2D/25(OH)D (×103)1.4 ± 0.771.4 ± 7.40.6 
Mean age in 1990 (yr)58.5 ± 6.658.5 ± 6.6Matched
Mean solar radiationd in 1990 (Langleys/day)354 ± 61350 ± 610.4 
Mean vitamin D intake (IU/day)313 ± 187333 ± 2160.2 
Mean calcium intake (mg/day)977 ± 334992 ± 3330.6 
Vitamin D supplement use in 1990 (%)36.538.30.6 
Calcium supplement use in 1990 (%)49.148.50.9 
Mean phosphorus intake (mg/day)1153 ± 1731160 ± 1880.6 
Mean protein intake (g/day)75.2 ± 9.875.1 ± 10.90.9 
Mean body mass index (kg/m2)25.0 ± 4.024.9 ± 3.80.8 
Mean physical activity (METe-h/week)14.6 ± 19.216.1 ± 19.20.3 
Regular aspirin use (%)22.729.40.05
Mean alcohol intake (g/day)7.3 ± 10.66.5 ± 9.40.3 
Mean cigarette pack-years smoked18.1 ± 22.615.2 ± 21.50.08
Mean red meat intake (servings/day)0.29 ± 0.200.29 ± 0.210.9 
Mean folate intake in 1980 (μg/day)356 ± 217367 ± 2530.6 
Mean methionine intake (g/day)1.79 ± 0.291.79 ± 0.310.9 
Postmenopausal hormone use in 1990 (%)32.238.70.07
  • a Unless otherwise indicated, values for characteristics are the average exposure calculated from the 1980–1990 questionnaires.

  • b For the hypothesis test of no difference in means (paired t test) or distribution (McNemar’s test) between adenoma cases and controls.

  • c Wilcoxon (nonparametric) sign-rank test: P = 0.4 and 0.8 for 1,25(OH)2D and 25(OH)D, respectively.

  • d Mean daily solar UV irradiation to the postal code area of residence in 1990.

  • e MET, metabolic equivalent tasks.