Table 1.
Selected baseline characteristics (medians and interquartile ranges, or percents) for cases and controls
| Median (25%-75%) or percents |
|||
|---|---|---|---|
| Characteristic | Cases, n=232 | Controls, n=464 | p value* |
| Age (y) | 62 (57–65) | 61 (57–64) | 0.60 |
| Height (cm) | 174 (170–178) | 174 (169–178) | 0.65 |
| Weight (kg) | 79 (71–86) | 78 (70–86) | 0.20 |
| Body mass index (kg/m2) | 26.0 (23.9–28.6) | 25.7 (23.3–28.2) | 0.15 |
| No. of cigarettes smoked per day | 20 (13–25) | 20 (12–25) | 0.95 |
| Years of smoking | 40 (35–45) | 40 (35–45) | 0.67 |
| Benign prostatic hyperplasia (%) | 8.2 | 5.4 | 0.15 |
| Family history of prostate cancer (%)† | 5.4 | 4.3 | 0.62 |
| Physical activity (% active) | 9.9 | 11.6 | 0.49 |
| Urban residence (%) | 65.5 | 64.0 | 0.70 |
| Married (%) | 78.5 | 82.3 | 0.22 |
| Education (% >elementary school) | 19.8 | 23.7 | 0.25 |
| History of chronic renal failure (%) | 0 | 0.43 | 0.32 |
| History of diabetes mellitus (%) | 5.2 | 4.5 | 0.71 |
| History of hypertension (%) | 22.0 | 19.3 | 0.40 |
| Hypertension at baseline (%) | 67.2 | 63.4 | 0.32 |
| Blood pressure – systolic (mm Hg) | 142 (130–158) | 142 (130–156) | 0.77 |
| Blood pressure – diastolic (mm Hg) | 88 (80–96) | 88 (80–94) | 0.32 |
| Daily dietary intake‡ | |||
| Energy (kcal) | 2537 (2069–3065) | 2486 (2091–2994) | 0.66 |
| Protein(g) | 91 (84–99) | 91 (83–99) | 0.95 |
| Fat (g) | 119 (111–130) | 119 (108–128) | 0.22 |
| Carbohydrate (g) | 259 (238–281) | 261 (240–284) | 0.44 |
| Folate (ug) | 328 (291–358) | 330 (292–365) | 0.24 |
| Methionine (mg) | 1923 (1762–2210) | 1957 (1769–2194) | 0.78 |
| Alcohol (g) | 7.9 (1.7–20.5) | 9.3 (1.7–22.9) | 0.37 |
| Meat (g) | 181 | 174 | 0.23 |
| Serum biomarker concentrations§ | |||
| Creatinine (mg/dL) | 1.13 (1.05–1.23) | 1.10 (1.02–1.19) | 0.004 |
| α-Tocopherol (mg/L) | 11.4 (9.7–13.4) | 11.8 (10.0–13.8) | 0.19 |
| β-Carotene (ug/L) | 173 (119–274) | 178 (111–260) | 0.71 |
| Retinol (ug/L) | 575 (508–648) | 572 (493–650) | 0.49 |
| Cholesterol (mmol/L) | 6.25 (5.38–7.04) | 6.14 (5.42–6.90) | 0.66 |
| Folate (ng/mL) | 3.85 (3.04–4.82) | 3.84 (3.03–4.76) | 0.75 |
| Homocysteine (nmol/mL) | 12.2 (10.3–14.3) | 11.8 (10.1–14.2) | 0.74 |
*
p-value based on Chi-squared 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