Table 2.
Cohort characteristics at baseline entry into the UKB.
| <50 years (n = 117,830) | 50–59 years (n = 167,115) | >59 years (n = 217,463) | Overall (N = 502,408) | |
|---|---|---|---|---|
| Sex assigned at birth | ||||
| Females | 64,641 (54.9%) | 94,004 (56.3%) | 114,679 (52.7%) | 273,324 (54.4%) |
| Males | 53,189 (45.1%) | 73,111 (43.7%) | 102,784 (47.3%) | 229,084 (45.6%) |
| Age | ||||
| Mean (SD) | 45.0 (2.74) | 54.8 (2.88) | 64.1 (2.85) | 56.5 (8.09) |
| Systolic blood pressure | ||||
| Mean (SD) | 129 (15.9) | 136 (17.7) | 144 (18.7) | 138 (18.7) |
| Missing | 374 (0.3%) | 408 (0.2%) | 543 (0.2%) | 1,325 (0.3%) |
| Diastolic blood pressure | ||||
| Mean (SD) | 81 (10.4) | 82 (10) | 83 (10.2) | 82 (10.2) |
| Missing | 374 (0.3%) | 541 (0.2%) | 408 (0.2%) | 1,323 (0.3%) |
| Glycated hemoglobin (HbA1C) in % | ||||
| Mean (SD) | 5.27 (0.547) | 5.45 (0.624) | 5.56 (0.630) | 5.46 (0.620) |
| Missing | 8,713 (7.4%) | 12,148 (7.3%) | 15,133 (7.0%) | 35,994 (7.2%) |
| Cholesterol (mg/dL) | ||||
| Mean (SD) | 212 (39.4) | 225 (43.0) | 221 (47.1) | 220 (44.3) |
| Missing | 7,844 (6.7%) | 10,967 (6.6%) | 14,095 (6.5%) | 32,906 (6.5%) |
| BMI | ||||
| Mean (SD) | 27.0 (4.98) | 27.5 (4.97) | 27.6 (4.55) | 27.4 (4.80) |
| Missing | 763 (0.6%) | 1,020 (0.6%) | 1,321 (0.6%) | 3,104 (0.6%) |
| Fruit and vegetable servings per day | ||||
| Mean (SD) | 3.26 (2.17) | 3.60 (2.20) | 3.83 (2.24) | 3.62 (2.22) |
| Missing | 3,501 (3.0%) | 4,806 (2.9%) | 7,091 (3.3%) | 15,398 (3.1%) |
| Bread and cereal servings per day | ||||
| Mean (SD) | 2.29 (1.31) | 2.34 (1.28) | 2.50 (1.26) | 2.40 (1.28) |
| Missing | 3,229 (2.7%) | 3,927 (2.3%) | 4,879 (2.2%) | 12,035 (2.4%) |
| Red meat score | ||||
| Mean (SD) | 0.853 (0.989) | 0.922 (1.03) | 1.03 (1.06) | 0.952 (1.03) |
| Missing | 1,862 (1.6%) | 2,131 (1.3%) | 3,005 (1.4%) | 6,998 (1.4%) |
| Salt added to food | ||||
| Always | 6,525 (5.5%) | 7,942 (4.8%) | 9,959 (4.6%) | 24,426 (4.9%) |
| Usually | 12,579 (10.7%) | 19,105 (11.4%) | 26,700 (12.3%) | 58,384 (11.6%) |
| Sometimes | 33,458 (28.4%) | 47,381 (28.4%) | 59,753 (27.5%) | 140,592 (28.0%) |
| Never/rarely | 64,932 (55.1%) | 92,344 (55.3%) | 120,605 (55.5%) | 277,881 (55.3%) |
| Missing | 336 (0.3%) | 343 (0.2%) | 446 (0.2%) | 1,125 (0.2%) |
| Alcohol intake frequency | ||||
| Daily or almost daily | 17,722 (15.0%) | 33,423 (20.0%) | 50,608 (23.3%) | 101,753 (20.3%) |
| Three or four times a week | 27,276 (23.1%) | 40,373 (24.2%) | 47,773 (22.0%) | 115,422 (23.0%) |
| Once or twice a week | 33,956 (28.8%) | 43,520 (26.0%) | 51,794 (23.8%) | 129,270 (25.7%) |
| One to three times a month | 15,965 (13.5%) | 18,414 (11.0%) | 21,461 (9.9%) | 55,840 (11.1%) |
| Special occasions only | 13,208 (11.2%) | 18,349 (11.0%) | 26,439 (12.2%) | 57,996 (11.5%) |
| Never | 9,253 (7.9%) | 12,549 (7.5%) | 18,825 (8.7%) | 40,627 (8.1%) |
| Missing | 450 (0.4%) | 487 (0.3%) | 563 (0.3%) | 1,500 (0.3%) |
| Smoking status | ||||
| Current | 16,438 (14.0%) | 18,623 (11.1%) | 17,901 (8.2%) | 52,962 (10.5%) |
| Previous | 28,965 (24.6%) | 53,884 (32.2%) | 90,174 (41.5%) | 173,023 (34.4%) |
| Never | 71,805 (60.9%) | 93,766 (56.1%) | 107,904 (49.6%) | 273,475 (54.4%) |
| Missing | 622 (0.5%) | 842 (0.5%) | 1,484 (0.7%) | 2,948 (0.6%) |
| Days per week with 10+ minutes of moderate activity | ||||
| Mean (SD) | 3.44 (2.30) | 3.48 (2.34) | 3.84 (2.33) | 3.63 (2.33) |
| Missing | 4,991 (4.2%) | 8,211 (4.9%) | 14,062 (6.5%) | 27,264 (5.4%) |
| Days per week with 10+ minutes of vigorous activity | ||||
| Mean (SD) | 2.04 (1.95) | 1.81 (1.95) | 1.75 (1.97) | 1.84 (1.96) |
| Missing | 4,559 (3.9%) | 8,014 (4.8%) | 15,000 (6.9%) | 27,573 (5.5%) |
| Hours of sleep per day | ||||
| Mean (SD) | 7.12 (1.07) | 7.06 (1.09) | 7.24 (1.14) | 7.15 (1.11) |
| Missing | 976 (0.8%) | 1,375 (0.8%) | 1,863 (0.9%) | 4,214 (0.8%) |
| Number of days with tension, fidgetiness, or restlessness in the last two weeks | ||||
| Nearly every day | 3,062 (2.6%) | 3,693 (2.2%) | 2,585 (1.2%) | 9,340 (1.9%) |
| Several days | 29,998 (25.5%) | 37,635 (22.5%) | 37,798 (17.4%) | 105,431 (21.0%) |
| More than half the days | 4,184 (3.6%) | 5,004 (3.0%) | 4,238 (1.9%) | 13,426 (2.7%) |
| Not at all | 75,096 (63.7%) | 113,730 (68.1%) | 163,193 (75.0%) | 352,019 (70.1%) |
| Missing | 5,490 (4.7%) | 7,053 (4.2%) | 9,649 (4.4%) | 22,192 (4.4%) |
| Frequency of friends or family visits | ||||
| Almost daily | 9,991 (8.5%) | 16,680 (10.0%) | 31,085 (14.3%) | 57,756 (11.5%) |
| 2-4 times a week | 30,292 (25.7%) | 46,513 (27.8%) | 75,206 (34.6%) | 152,011 (30.3%) |
| About once a week | 46,005 (39.0%) | 60,754 (36.4%) | 69,618 (32.0%) | 176,377 (35.1%) |
| About once a month | 18,392 (15.6%) | 24,558 (14.7%) | 23,527 (10.8%) | 66,477 (13.2%) |
| Once every few months or never | 11,032 (9.4%) | 15,856 (9.5%) | 14,969 (6.9%) | 41,857 (8.3%) |
| Missing | 2,118 (1.8%) | 2,754 (1.6%) | 3,058 (1.4%) | 7,930 (1.6%) |
Blood sugar levels were measured as hemoglobin A1c (HbA1C). The red meat score is based on beef, pork, and lamb/mutton consumption, in which an individual score was first assigned for each meat type (“Never” or “Less than once a week” with 0; “Once a week” or “2–4 times a week” with 1; and “5–6 times a week” or “Once or more daily” with 2); these were then summed, with a score of 1–2 dichotomized into 1 and less than 1 or more than 2 with a 0. Moderate activity includes physical activities such as carrying light loads or cycling; vigorous activity includes activities such as fast cycling, aerobics, or heavy lifting. BMI stands for Body Mass Index.