Table 1.
Characteristics of the study population from the lifelines cohort, stratified for sex.
| Characteristic a | Total, n (%) (N = 56 896) | Male (N = 22 577) | Female (N = 34 319) | P b |
|---|---|---|---|---|
| Age, years; mean ± SD | 55.8 ± 12.2 | 57.3 ± 12.2 | 54.8 ± 12.1 | < 0.001 |
| Male | 22 577 (39.7) | 22 577 (100) | 0 | – |
| AD prevalence, n (%) [95% CI] | ||||
| Lifetime | 5196 (9.1) [8.9–9.4] | 1472 (6.5) [6.2–6.9] | 3724 (10.9) [10.5–11.2] | < 0.001 |
| Point | 1840 (3.3) [3.1–3.4] | 594 (2.7) [2.5–2.9] | 1246 (3.7) [3.5–3.9] | < 0.001 |
| Severity prevalence, c n (%) [95% CI] | ||||
| Clear or mild | 541 (1.0) [0.9–1.0] | 205 (0.9) [0.8–1.0] | 336 (1.0) [0.9–1.1] | 0.36 |
| Moderate to severe | 1288 (2.3) [2.1–2.4] | 386 (1.7) [1.5–1.9] | 902 (2.7) [2.5–2.8] | < 0.001 |
| Hand eczema, n (%) [95% CI] | 8482 (15.0) [14.7–15.3] | 2409 (10.7) [10.3–11.1] | 6073 (17.8) [17.4–18.2] | < 0.001 |
| Asthma, n (%) [95% CI] | 4631 (8.2) [7.9–8.4] | 1758 (7.8) [7.5–8.2] | 2873 (8.4) [8.1–8.7] | 0.01 |
| Smoking | ||||
| Smoking status | < 0.001 | |||
| Never smoker | 26 253 (47.0) | 9767 (43.9) | 16 486 (48.9) | < 0.001 |
| Former smoker | 20 499 (36.7) | 8509 (38.3) | 11 990 (35.6) | < 0.01 |
| Current smoker | 9163 (16.4) | 3953 (17.8) | 5210 (15.5) | < 0.001 |
| Cigarettes/day | ||||
| > 0–7.9 | 3622 (6.5) | 1517 (6.8) | 2105 (6.2) | 0.01 |
| 8–15 | 3897 (7.0) | 1612 (7.3) | 2285 (6.8) | 0.03 |
| > 15 | 1644 (2.9) | 824 (3.7) | 820 (2.4) | < 0.001 |
| Pack‐years | ||||
| 0 | 26 252 (48.1) | 9766 (45.3) | 16 486 (50.0) | < 0.001 |
| ≤ 15 | 20 330 (37.3) | 7591 (35.2) | 12 739 (38.6) | < 0.001 |
| > 15 | 7941 (14.6) | 4198 (19.5) | 3743 (11.4) | < 0.001 |
| Alcohol consumption, drinks/day | ||||
| 0 (nondrinker) | 11 096 (21.0) | 2187 (10.8) | 8909 (27.3) | < 0.001 |
| ≤ 1 (light drinker) | 26 534 (50.2) | 8941 (44.3) | 17 593 (54.0) | < 0.001 |
| > 1–2 (moderate drinker) | 11 152 (21.1) | 6083 (30.1) | 5069 (15.5) | < 0.001 |
| > 2 (heavy drinker) | 4025 (7.6) | 2987 (14.8) | 1038 (3.2) | < 0.001 |
| Stress | ||||
| Total LTE score | ||||
| 0 | 24 993 (44.7) | 10 368 (46.8) | 14 625 (43.3) | < 0.001 |
| 1 | 15 622 (27.9) | 6124 (27.6) | 9498 (28.1) | 0.2 |
| 2 | 8881 (15.9) | 3341 (15.1) | 5540 (16.4) | < 0.001 |
| ≥ 3 | 6421 (11.5) | 2325 (10.5) | 4096 (12.1) | < 0.001 |
| Total LDI score | ||||
| 0 | 12 666 (22.7) | 5802 (26.2) | 6864 (20.3) | < 0.001 |
| 1–2 | 21 944 (39.3) | 9240 (41.7) | 12 704 (37.6) | < 0.001 |
| 3–4 | 12 492 (22.3) | 4444 (20.1) | 8048 (23.8) | < 0.001 |
| ≥ 5 | 8803 (15.7) | 2671 (12.1) | 6132 (18.2) | < 0.001 |
| Obesity | ||||
| BMI, kg/m2 | ||||
| Underweight (< 18.5) | 397 (0.7) | 59 (0.3) | 338 (1.0) | < 0.001 |
| Normal weight (18.5–24.9) | 25 562 (44.9) | 8526 (36.6) | 17 306 (50.4) | < 0.001 |
| Overweight (25–29.9) | 22 663 (39.8) | 11 157 (49.4) | 11 506 (33.5) | < 0.001 |
| Class I obesity (30–34.9) | 6333 (11.1) | 2605 (11.5) | 3728 (10.9) | 0.01 |
| Class II/III obesity (≥ 35) | 1922 (3.4) | 492 (2.2) | 1430 (4.2) | < 0.001 |
| WC, cm | < 0.001 | |||
| Male | ||||
| < 102 | – | 16 931 (75.0) | – | |
| ≥ 102 | – | 5638 (25.0) | – | |
| Female | ||||
| < 88 | – | – | 20 255 (59.0) | |
| ≥ 88 | – | – | 14 053 (41.0) | |
| Physical activity, min/week | ||||
| MVPA | ||||
| 0 | 3345 (6.4) | 1412 (6.9) | 1933 (6.1) | < 0.001 |
| > 0–249 | 16 463 (31.5) | 5445 (26.6) | 11 018 (34.6) | < 0.001 |
| > 249–743 | 16 389 (31.3) | 6008 (29.4) | 10 381 (32.6) | < 0.001 |
| > 743 | 16 122 (30.8) | 7586 (37.1) | 8536 (26.8) | < 0.001 |
| VPA | ||||
| 0 | 8094 (15.5) | 3567 (17.4) | 4527 (14.2) | < 0.001 |
| > 0–120 | 15 829 (30.3) | 5669 (27.7) | 10 160 (31.9) | < 0.001 |
| > 120–295 | 13 705 (26.2) | 4899 (24.0) | 8806 (27.6) | < 0.001 |
| > 295 | 14 691 (28.1) | 6316 (30.9) | 8375 (26.3) | < 0.001 |
| Diet | ||||
| Vegetarian/vegan | 1183 (2.1) | 251 (1.1) | 932 (2.8) | < 0.001 |
| Total LLDS score | ||||
| 0–18 | 7549 (15.2) | 3911 (19.9) | 3638 (12.1) | < 0.001 |
| 19–22 | 10 317 (20.8) | 4864 (24.7) | 5453 (18.2) | < 0.001 |
| 23–25 | 9473 (19.1) | 3957 (20.1) | 5516 (18.4) | < 0.001 |
| 26–29 | 11 347 (22.8) | 4075 (20.7) | 7272 (24.2) | < 0.001 |
| 30–48 | 11 008 (22.2) | 2884 (14.6) | 8124 (27.1) | < 0.001 |
| Sleep duration, h/day | ||||
| ≤ 7 | 24 293 (43.3) | 11 401 (51.3) | 12 892 (38.0) | < 0.001 |
| > 7–9 | 31 093 (55.4) | 10 588 (47.7) | 20 505 (60.4) | < 0.001 |
| > 9 | 760 (1.4) | 214 (1.0) | 546 (1.6) | < 0.001 |
AD, atopic dermatitis; BMI, body mass index; LDI, Long‐term Difficulties Inventory; LLDS, Lifelines Diet Score; LTE, List of Threatening Events; MVPA, moderate to vigorous physical activity; VPA, vigorous physical activity; WC, waist circumference.
a
all characteristics excluding BMI and WC are self‐reported;
b
significant P values (< 0.05) are shown in bold;
c
severity measured according to the Patient‐Oriented Eczema Measure among the participants with physician‐diagnosed AD.