Table 1.
Baseline characteristics of CRC cases and controls in the PLCO Cancer Screening Trial Cohort by sex and the ATBC Cohorta
| Characteristics | PLCO Women (n = 466) |
PLCO Men (n = 524) |
ATBC Men (n = 1196) |
|||
|---|---|---|---|---|---|---|
| Controls (n = 233) | Cases (n = 233) | Controls (n = 262) | Cases (n = 262) | Controls (n = 598) | Cases (n = 598) | |
| Mean age at baseline (SD), yb,c | 64.1 (5.4) | 64.2 (5.3) | 64.0 ( 5.1) | 64.0 ( 5.0) | 56.6 (4.8) | 56.6 (4.8) |
| Race, % (No.) | ||||||
| Asian | 0.9 (2) | 0.9 (2) | 5.0 (13) | 5.0 (13) | 0 (0) | 0 (0) |
| Black, Non-Hispanic | 5.6 (13) | 5.6 (13) | 3.8 (10) | 3.8 (10) | 0 (0) | 0 (0) |
| Hispanic, American Indian, or Pacific Islander | 1.3 (3) | 1.3 (3) | 2.7 (7) | 2.7 (7) | 0 (0) | 0 (0) |
| Non-Hispanic whiteb | 92.3 (215) | 92.3 (215) | 88.5 (232) | 88.5 (232) | 100 (598) | 100 (598) |
| College graduate, % (No.) | 34.4 (80) | 23.3 (54) | 43.3 (114) | 37.6 (99) | 4.4 (26) | 5.1 (31) |
| Current smoker, % (No.) | 5.3 (12) | 9.1 (21) | 8.4 (22) | 11.4 (30) | 100 (598) | 100 (598) |
| Self-reported diabetes, % (No.) | 4.9 (11) | 4.8 (11) | 7.3 (19) | 10.8 (28) | 3.1 (19) | 2.5 (15) |
| Family history of colorectal cancer, % (No.) | 14.3 (33) | 12.7 (30) | 9.1 (24) | 13.2 (35) | — | — |
| Vigorous activity, 4+ h/wk, % (No.) | 22.5 (52) | 21.2 (49) | 24.5 (64) | 24.5 (64) | — | — |
| Leisure time physical activity, 3+ times/wk, % (No.) | — | — | — | — | 19.9 (119) | 17.7 (106) |
| Never HRT user (women only), % (No.) | 31.1 (72) | 32.7 (76) | — | — | — | — |
| Alcohol drinker, % (No.) | 75.1 (175) | 70.3 (164) | 83.3 (218) | 86.4 (226) | 90.8 (543) | 94.7 (566) |
| Mean alcohol intake (SD), drinks/d | 0.4 (0.8) | 0.5 (1.1) | 1.3 (1.9) | 1.4 (2.9) | 1.3 (1.5) | 1.5 (1.6) |
| Mean whole grain intake (SD), oz/d/1000 kcal | 0.6 (0.4) | 0.6 (0.4) | 0.5 (0.4) | 0.5 (0.3) | 2.1 (1.4) | 2.0 (1.5) |
| Mean unprocessed red meat intake (SD), g/d/1000 kcal | 22.2 (13.9) | 22.0 (14.5) | 29.6 (16.7) | 33.0 (18.9) | 27.1 (11.8) | 28.0 (11.8) |
| Mean processed meat intake (SD), g/d/1000 kcal | 4.3 (4.5) | 4.3 (5.8) | 6.9 (6.6) | 8.6 (9.3) | 28.1 (17.9) | 28.4 (17.8) |
| Mean energy intake (SD), kcal/d | 1674.9 (595.3) | 1753.7 (675.0) | 2254.9 (948.2) | 2439.5 (925.4) | 2725.4 (688.6) | 2691.7 (704.4) |
| Mean body mass index (SD), kg/m² | 26.8 (5.4) | 27.6 (5.4) | 27.1 (3.8) | 28.6 (4.7) | 26.1 (3.7) | 26.4 (3.7) |
| Bile acids, Mean (SD) | ||||||
| Chenodeoxycholic acid, ng/mL | 61.2 ( 117.4) | 115.4 (557.6) | 123.4 (329.9) | 107.2 (207.3) | 132.0 (257.0) | 151.1 (377.8) |
| Cholic acid, ng/mL | 28.1 (78.6) | 55.2 (242.1) | 70.1 (209.7) | 43.9 (92.9) | 94.7 (192.8) | 118.2 (462.5) |
| Deoxycholic acid, ng/mL | 115.7 (123.5) | 154.5 (203.6) | 138.1 (210.2) | 135.1 (145.5) | 111.7 (156.9) | 124.5 (164.7) |
| Lithocholic acid, ng/mL | 4.2 (5.5) | 5.3 (8.4) | 4.5 (5.5) | 5.8 (7.6) | 3.0 (2.9) | 3.3 (4.1) |
| Ursodeoxycholic acid, ng/mL | 17.1 (31.7) | 32.8 (165.1) | 20.4 (40.6) | 19.0 (34.8) | 22.6 (38.9) | 23.7 (41.9) |
| Glycochenodeoxycholic acid, ng/mL | 263.5 (290.0) | 359.3 (451.3) | 388.5 (534.0) | 409.9 (558.1) | 206.1 (237.8) | 234.6 (305.5) |
| Glycocholic acid, ng/mL | 114.9 (199.0) | 145.7 (408.1) | 120.2 (180.0) | 168.4 (366.3) | 51.5 (95.0) | 65.2 (121.5) |
| Glycodeoxycholic acid, ng/mL | 140.4 (179.7) | 205.8 (259.1) | 170.9 (291.6) | 177.8 (244.8) | 53.9 (79.7) | 65.1 (97.6) |
| Glycolithocholic acid, ng/mL | 7.2 (13.2) | 9.4 (14.6) | 10.0 (17.6) | 9.3 (13.1) | 3.9 (5.2) | 4.1 (5.0) |
| Glycoursodeoxycholic acid, ng/mL | 48.6 (80.2) | 60.9 (121.2) | 47.3 (65.5) | 49.3 (75.4) | 36.6 (45.6) | 37.2 (49.4) |
| Taurochenodeoxycholic acid, ng/mL | 54.8 (81.3) | 68.0 (115.8) | 48.8 (79.7) | 72.7 (165.5) | 26.0 (32.5) | 36.6 (128.2) |
| Taurocholic acid, ng/mL | 27.9 (80.5) | 30.7 (105.2) | 14.9 (31.9) | 32.0 (111.3) | 8.5 (28.0) | 14.9 (91.3) |
| Taurodeoxycholic acid, ng/mL | 30.7 (47.7) | 40.8 (61.7) | 21.2 (41.6) | 29.5 (57.5) | 9.0 (21.0) | 10.3 (16.4) |
| Taurolithocholic acid, ng/mL | 1.2 (2.3) | 1.4 (2.8) | 1.2 (2.6) | 1.5 (3.1) | 1.4 (1.5) | 1.4 (0.7) |
| Tauroursodeoxycholic acid, ng/mL | 2.2 (4.6) | 2.6 (6.2) | 1.3 (3.6) | 2.3 (8.9) | 1.7 (1.5) | 1.7 (1.9) |
| Short-chain fatty acids, Mean (SD) | ||||||
| Acetic acid, ng/mL | 1747.5 (1455.0) | 1470.4 (1227.8) | 1661.1 (1458.3) | 2264.4 (5601.9) | 3223.2 ( 8269.5) | 3165.2 (7084.3) |
| Butyric acid, ng/mL | 31.5 (24.2) | 36.3 (31.2) | 31.1 (27.7) | 39.9 (74.4) | 38.8 (19.0) | 39.0 (23.1) |
| Propionic acid, ng/mL | 41.7 (40.5) | 48.7 (51.4) | 42.6 (40.7) | 49.6 (69.3) | 75.6 (36.0) | 76.9 (41.3) |
| Hexanoic acid, ng/mL | 45.4 (21.1) | 45.8 (22.2) | 40.7 (17.0) | 42.3 (18.8) | 84.5 (23.8) | 86.3 (26.5) |
| Isobutyric acid, ng/mL | 72.6 (84.3) | 82.8 (122.5) | 71.7 (74.6) | 76.3 (112.9) | 95.5 (25.0) | 96.1 (26.3) |
| Isovaleric acid, ng/mL | 59.2 (30.5) | 56.5 (29.2) | 72.6 (32.8) | 75.4 (40.2) | 84.9 (30.4) | 86.0 (33.8) |
a
Values are standardized to the age distribution of the study population. ATBC = Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study; CRC = colorectal cancer; PLCO = Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial.
b
Matching factor in PLCO.
c
Matching factor in ATBC.