TABLE 1.
Subject characteristics by MTHFR 677C>T genotype
| CC (n = 185) | CT (n = 119) | TT (n = 32) | P value1 | ||
| Age (y) | 57 (55, 59)2 | 57 (54, 60) | 54 (48, 60) | 0.58 | |
| Sex [n (%)] | 0.36 | ||||
| Male | 67 (36) | 51 (43) | 10 (31) | ||
| Female | 118 (64) | 68 (57) | 22 (69) | ||
| Ethnic group [n (%)] | 0.013 | ||||
| White | 114 (62) | 87 (73) | 25 (78) | ||
| Black | 50 (27) | 16 (13) | 3 (9) | ||
| Asian | 11 (6) | 5 (4) | 2 (6) | ||
| Other | 5 (3) | 5 (4) | 1 (3) | ||
| Not recorded | 5 (3) | 6 (5) | 1 (3) | ||
| BMI (kg/m2) | 26.9 (25.9, 28.0) | 26.7 (25.7, 27.7) | 27.6 (25.2, 29.9) | 0.80 | |
| Smoking [n (%)] | |||||
| n | 172 | 112 | 30 | ||
| Nonsmoker | 132 (77) | 87 (78) | 20 (67) | 0.44 | |
| Smoker | 40 (23) | 25 (22) | 10 (33) | ||
| Supplement use [n (%)] | 0.80 | ||||
| n | 168 | 111 | 30 | ||
| Nonuser user | 114 (68) | 78 (70) | 22 (73) | ||
| User | 54 (32) | 33 (30) | 8 (27) | ||
| Folate-containing supplement use [n (%)] | |||||
| n | 168 | 111 | 30 | ||
| Nonuser | 145 (86) | 94 (85) | 26 (87) | ||
| User | 23 (14) | 17 (15) | 4 (13) | ||
| Dietary folate intake (μg/d)4 | 327 (287, 366) | 376 (316, 436) | 370 (284, 455) | ||
| Total folate intake (diet + supplements) (μg/d) | 345 (297, 393) | 415 (335, 495) | 392 (322, 462) | 0.21 | |
| Alcohol intake (g/d) | 1 (0–78)5 | 1 (0–103) | 1 (0–64) | 0.59 |
1
Differences between genotypes were tested by using chi-square tests (sex, smoking, and supplement use), ANOVA (age, BMI, and folate intake), and the Kruskal-Wallis test (alcohol intake).
2
Mean; 95% CI in parentheses (all such values).
3
The chi-square test was for white compared with black because of the limited number of subjects in the other groups.
4
= 33, 18, and 9 for the CC, CT, and TT groups, respectively.
5
Median; range in parentheses (all such values).