Table 1.

Selected baseline characteristics (medians and interquartile ranges, or percents) for cases and controls

CharacteristicMedian (25-75%) or percentsP*
Cases, n = 232Controls, n = 464
Age, y62 (57-65)61 (57-64)0.60
Height, cm174 (170-178)174 (169-178)0.65
Weight, kg79 (71-86)78 (70-86)0.20
Body mass index, kg/m226.0 (23.9-28.6)25.7 (23.3-28.2)0.15
No. of cigarettes smoked per day20 (13-25)20 (12-25)0.95
Years of smoking40 (35-45)40 (35-45)0.67
Benign prostatic hyperplasia (%)8.25.40.15
Family history of prostate cancer (%)5.44.30.62
Physical activity (% active)9.911.60.49
Urban residence (%)65.564.00.70
Married (%)78.582.30.22
Education (% >elementary school)19.823.70.25
History of chronic renal failure (%)00.430.32
History of diabetes mellitus (%)5.24.50.71
History of hypertension (%)22.019.30.40
Hypertension at baseline (%)67.263.40.32
Blood pressure - systolic, mm Hg142 (130-158)142 (130-156)0.77
Blood pressure - diastolic, mm Hg88 (80-96)88 (80-94)0.32
Daily dietary intake
Energy, kcal2,537 (2,069-3,065)2,486 (2,091-2,994)0.66
Protein, g91 (84-99)91 (83-99)0.95
Fat, g119 (111-130)119 (108-128)0.22
Carbohydrate, g259 (238-281)261 (240-284)0.44
Folate, ug328 (291-358)330 (292-365)0.24
Methionine, mg1,923 (1762-2210)1,957 (1769-2194)0.78
Alcohol, g7.9 (1.7-20.5)9.3 (1.7-22.9)0.37
Meat, g181 (141-223)174 (145-213)0.23
Serum biomarker concentrations§
Creatinine, mg/dL1.13 (1.05-1.23)1.10 (1.02-1.19)0.004
α-Tocopherol, mg/L11.4 (9.7-13.4)11.8 (10.0-13.8)0.19
β-Carotene, ug/L173 (119-274)178 (111-260)0.71
Retinol, ug/L575 (508-648)572 (493-650)0.49
Cholesterol, mmol/L6.25 (5.38-7.04)6.14 (5.42-6.90)0.66
Folate, ng/mL3.85 (3.04-4.82)3.84 (3.03-4.76)0.75
Homocysteine, nmol/mL12.2 (10.3-14.3)11.8 (10.1-14.2)0.74
  • *P value based on χ2 tests (for categorical variables) and Wilcoxon rank sum tests (for continuous variables).

  • Family history data available on only 65% of these subjects.

  • Dietary variables (except alcohol) are energy adjusted (n = 222 cases and 443 controls).

  • §Eight cases and 10 controls were lost due to cracked vials.