Table 1.
Demographic and Epidemiologic Characteristics of Included Study Participants.
| HPFS | NHS | PHS | PLCO | VITAL | WHI | Total | ||
|---|---|---|---|---|---|---|---|---|
| Total cases a | 92 | 134 | 102 | 737 | 178 | 1006 | 2249 | |
| No. deaths (%) | 47 (51) | 58 (43) | 72 (71) | 226 (31) | 64 (36) | 305 (30) | 772 (34) | |
| No. CRC deaths (%) | 29 (32) | 40 (30) | 54 (53) | 158 (21) | 39 (22) | 230 (23) | 550 (24) | |
| Median years follow-up | 5.5 | 8.9 | 5.9 | 4.7 | 4.6 | 3.9 | 4.5 | |
| Sex (% female) | 0 | 100 | 0 | 44 | 46 | 100 | 69 | |
| Mean age at reference (SD) | 65.5 (8.5) | 59.7 (6.3) | 61.4 (8.7) | 64.1 (5.2) | 66.0 (6.4) | 66.1 (6.6) | 64.8 (6.6) | |
| Mean age at diagnosis (SD) | 71.5 (8.5) | 66.1 (6.2) | 67.3 (8.9) | 70.2 (5.7) | 70.6 (6.6) | 71.7 (7.0) | 70.6 (6.9) | |
| Smoking status (%) | ||||||||
| Current | 5 (05) | 22 (16) | 10 (10) | 75 (10) | 17 (10) | 71 (07) | 200 (09) | |
| Former | 47 (51) | 55 (41) | 63 (62) | 330 (45) | 98 (55) | 450 (45) | 1043 (46) | |
| Never | 40 (43) | 57 (43) | 29 (28) | 332 (45) | 63 (35) | 485 (48) | 1006 (45) | |
| Body mass index category (%) | ||||||||
| Normal (18.5–24.9) | 42 (46) | 77 (57) | 55 (54) | 207 (28) | 52 (29) | 334 (33) | 767 (34) | |
| Overweight (25.0–29.9) | 40 (43) | 42 (31) | 43 (42) | 343 (47) | 75 (42) | 351 (35) | 894 (40) | |
| Obese (≥ 30.0) | 10 (11) | 15 (11) | 4 (04) | 187 (25) | 51 (29) | 331 (32) | 588 (26) | |
| Stage at diagnosis (%) | ||||||||
| I | 30 (33) | 32 (24) | 24 (24) | 225 (31) | 59 (33) | 328 (33) | 698 (31) | |
| II | 19 (21) | 40 (30) | 26 (25) | 214 (29) | 45 (25) | 285 (28) | 629 (28) | |
| III | 23 (25) | 38 (28) | 30 (29) | 196 (27) | 46 (26) | 257 (26) | 590 (26) | |
| IV | 20 (22) | 24 (18) | 22 (22) | 102 (14) | 28 (16) | 136 (14) | 332 (15) | |
| Tumor site (%) | ||||||||
| Distal | 34 (37) | 43 (32) | 40 (39) | 184 (25) | 46 (26) | 248 (25) | 595 (26) | |
| Proximal | 35 (38) | 59 (44) | 45 (44) | 427 (58) | 101 (57) | 564 (56) | 1231 (55) | |
| Rectal | 22 (24) | 30 (22) | 13 (13) | 109 (15) | 29 (16) | 188 (19) | 391 (17) | |
| Not specified | 1 (01) | 2 (01) | 4 (04) | 17 (02) | 2 (01) | 6 (01) | 32 (01) | |
Abbreviations: HPFS, Health Professionals Follow-up Study; NHS, Nurses’ Health Study; PHS, Physicians’ Health Study; PLCO, The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial; VITAL, VITamins and Lifestyle Study; WHI, The Women’s Health Initiative.
a
Represents cases after exclusions (n = 1,051) and missing observations (n = 194).