Table 1. Baseline characteristics of study subjects (MMR gene mutation carriers and non-carriers).
|
Mutation carriers
|
Non-carriers
|
|||
|---|---|---|---|---|
| CRC-affected (N=659) number (%) | CRC-unaffected (N=665) number (%) | CRC-affected (N=36) number (%) | CRC-unaffected (N=1183) number (%) | |
| Sex | ||||
| Female | 332 (50) | 405 (61) | 19 (53) | 693 (59) |
| Age (year)a, mean (s.d.) | 44.0 (11.1) | 44.9 (13.7) | 56.8 (14.8) | 51.9 (15.6) |
| MMR gene mutated | ||||
| MLH1 | 273 (41) | 227 (34) | ||
| MSH2 | 308 (47) | 340 (51) | ||
| MSH6 | 40 (6) | 77 (12) | ||
| PMS2 | 38 (6) | 21 (3) | ||
| Country of recruitment | ||||
| Australia or New Zealand | 355 (54) | 484 (72) | 16 (44) | 967 (81) |
| USA | 216 (33) | 151 (23) | 15 (42) | 184 (16) |
| Canada | 88 (13) | 30 (5) | 5 (14) | 32 (3) |
| Source of recruitment | ||||
| Clinic based | 473 (72) | 599 (90) | 23 (64) | 1087 (92) |
| Population based | 186 (28) | 66 (10) | 13 (36) | 96 (8) |
| Cigarette smoking b | ||||
| Never | 319 (49) | 363 (55) | 15 (44) | 652 (55) |
| Ever | 338 (51) | 299 (45) | 19 (56) | 527 (45) |
| Unknown | 2 | 3 | 2 | 4 |
| Alcohol consumption c | ||||
| Never | 233 (36) | 193 (31) | 16 (44) | 417 (36) |
| Ever | 408 (64) | 439 (69) | 20 (56) | 732 (64) |
| Unknown | 18 | 33 | 0 | 34 |
| Body size, mean (s.d.) | ||||
| Height (cm) | 170.1 (10.1) | 169.8 (9.7) | 169.7 (9.5) | 169.4 (9.9) |
| Weight at age 20 (kg) | 66.9 (15.5) | 65.4 (14.6) | 65.8 (13.0) | 64.6 (13.8) |
| BMI at age 20 (kg m–2)d | 23.0 (4.0) | 22.5 (3.7) | 22.7 (3.3) | 22.4 (3.7) |
Abbreviations: BMI=body mass index; CRC=colorectal cancer; MMR=mismatch repair.
a
Age at first diagnosis of CRC for affected subjects; age at first polypectomy or diagnosis of another cancer or last contact for unaffected subjects (whichever came first).
b
Cigarette smoking status at age 20 years; cigarette smoking was defined as ever smoking one cigarette per day for 3 months or longer.
c
Alcohol consumption status at age 20 years; alcohol beverages include beer, wine, cider, spirits, mixed drinks or cocktails.
d
Calculated from self-reported height and weight at age 20 years.