Baseline characteristics of study participants according to depressive symptoms
| Characteristics (N, %) | Depressed | Non-depressed | P value |
| N | 18 904 (24.17) | 59 308 (75.83) | – |
| Age | <0.0001 | ||
| 50–59 | 8116 (42.93) | 26 199 (44.17) | |
| 60–69 | 5284 (27.95) | 19 461 (32.81) | |
| 70+ | 5504 (29.12) | 13 648 (23.01) | |
| Gender | <0.0001 | ||
| Men | 5489 (29.04) | 28 626 (48.27) | |
| Women | 13 415 (71.07) | 30 682 (51.73) | |
| Obesity | 3742 (20.58) | 9534 (16.47) | <0.0001 |
| Drinking | 7454 (39.59) | 30 873 (52.17) | <0.0001 |
| Smoking status | <0.0001 | ||
| Never smoker | 10 330 (55.34) | 31 452 (53.59) | |
| Ever smoker | 4274 (22.90) | 15 444 (26.32) | |
| Current smoker | 4061 (21.76) | 11 790 (20.09) | |
| Physical activity | <0.0001 | ||
| Hardly ever or never | 2981 (15.83) | 3386 (5.72) | |
| 1–3 times/month | 1116 (5.97) | 2466 (4.17) | |
| ≥1 times/week | 14 731 (78.24) | 53 318 (90.11) | |
| Marital status | 12 974 (68.71) | 47 273 (79.79) | <0.0001 |
| Education | <0.0001 | ||
| Less than secondary school | 9463 (50.06) | 22 310 (37.62) | |
| Upper secondary education | 6346 (33.57) | 22 514 (37.96) | |
| Tertiary education | 3095 (16.37) | 14 484 (24.42) | |
| No. of chronic diseases | <0.0001 | ||
| 0–1 | 11 975 (63.35) | 46 894 (79.07) | |
| 2–3 | 6099 (32.26) | 11 705 (19.74) | |
| ≥4 | 830 (4.39) | 709 (1.20) | |
| Taking medication for depression or anxiety | <0.0001 | ||
| Yes | 2604 (13.77) | 1629 (2.75) | |
| No | 16 300 (86.23) | 57 679 (97.25) | |