Table 1. The Distribution of Baseline Characteristics of Participants According to Depression Statusa.
| Baseline depression status | ||||||
|---|---|---|---|---|---|---|
| CKB cohort | DFTJ cohort | |||||
| Yes | No | P valueb | Yes | No | P valueb | |
| N | 3280 | 509,432 | 4723 | 21,575 | ||
| Age (years) | 51.5±10.0 | 52.0±10.7 | <.001 | 63.5±7.8 | 63.6±7.8 | .22 |
| Activity, MET-hours/day c | 19.9±14.1 | 21.1 ±13.9 | <.001 | 4.25±6.62 | 4.38±7.18 | .24 |
| BMI (continuous, kg/m2) | 23.2±3.4 | 23.7±3.4 | <.001 | 24.5±3.5 | 24.6±3.3 | .21 |
| BMI group (kg/m2) | ||||||
| <18.0 | 140 (4.3) | 13,927 (2.7) | <.001 | 104 (2.2) | 359 (1.7) | .09 |
| 18.0-24.9 | 2232 (68.1) | 327,501 (64.3) | 2678 (56.7) | 12,328 (57.1) | ||
| 25.0-29.9 | 790 (24.1) | 147,156 (28.9) | 1684 (35.7) | 7699 (35.7) | ||
| ≥30.0 | 118 (3.6) | 20,848 (4.1) | 257 (5.4) | 1189(5.5) | ||
| Female (%) | 2331 (71.1) | 300,178 (58.9) | <.001 | 2991 (63.3) | 11,517(53.4) | <.001 |
| Residential area | NA | NA | NA | |||
| Urban | 1132(34.5) | 225,049(44.2) | ||||
| Rural | 2148(65.5) | 284,383(55.8) | ||||
| Education (%) | <.001 | .01 | ||||
| Less than primary school | 1875 (57.1) | 258,480 (50.7) | 1455 (30.8) | 6481 (30.0) | ||
| Middle School | 889 (27.1) | 143,983 (28.3) | 1684 (35.7) | 7721 (35.8) | ||
| High School | 386 (11.8) | 77,122 (15.1) | 1155 (24.4) | 5081 (23.6) | ||
| College or higher | 130 (4.0) | 29,847 (5.9) | 429 (9.1) | 2292 (10.6) | ||
| Household income (yuan/year, %) | <.001 | NA | NA | NA | ||
| <10000 | 1339 (40.8) | 143,395 (28.1) | ||||
| 10000-19999 | 939 (28.7) | 148,017 (29.1) | ||||
| 20000-34999 | 673 (20.5) | 126,029 (24.7) | ||||
| ⩾35000 | 329 (10.0) | 91,991 (18.1) | ||||
| Marital status (%) | <.001 | <.001 | ||||
| Married | 2437 (74.3) | 462,025 (90.7) | 4002 (84.7) | 18,971 (87.9) | ||
| Widowed | 638 (19.5) | 35,919 (7.1) | 461 (9.8) | 1669 (7.7) | ||
| Separated / divorced | 155 (4.7) | 7787 (1.5) | 247 (5.2) | 872 (4.1) | ||
| Never married | 50 (1.5) | 3701 (0.7) | 13 (0.3) | 63 (0.3) | ||
| Drinking status (%) | <.001 | <.001 | ||||
| Never/ Occasional/ Monthly | 2762 (84.2) | 412,858 (80.5) | 3477 (73.6) | 15,788 (73.2) | ||
| Former/ Reduced intake | 194 (5.9) | 20,758 (4.1) | 352 (7.5) | 1181 (5.5) | ||
| Current | 1324 (9.9) | 75,816 (14.9) | 894 (18.9) | 4606 (21.3) | ||
| Smoking status (%) | <.001 | <.001 | ||||
| Never/ Occasional | 2424 (73.9) | 344,209 (67.6) | 3410 (72.2) | 15,089 (69.9) | ||
| Former | 146 (4.4) | 30,415 (6.0) | 558 (11.8) | 2545 (11.8) | ||
| Current | 710 (21.7) | 134,808 (26.4) | 755 (16.0) | 3941 (18.3) | ||
| Red meat (%) | <.001 | <.001 | ||||
| Daily | 610 (18.6) | 149,407 (29.3) | 1152 (24.4) | 5843 (27.1) | ||
| 4-6 days per week | 462 (14.1) | 91,340 (17.9) | 348 (7.4) | 1466 (6.8) | ||
| 1-3 days per week | 1352 (41.2) | 180,812 (35.5) | 1976 (41.8) | 9186 (42.6) | ||
| <1 day per week | 856 (26.1) | 87,873 (17.3) | 1247 (26.4) | 5080 (23.5) | ||
| Fresh vegetables (%) | .14 | .08 | ||||
| Daily | 3099 (94.5) | 482,837 (94.8) | 4400 (93.2) | 20,246 (93.8) | ||
| <1 per day | 181 (5.5) | 26,595 (5.2) | 323 (6.8) | 1329 (6.2) | ||
| Fresh fruits (%) | <.001 | .03 | ||||
| Daily | 420 (12.8) | 96,162 (18.9) | 2232 (47.3) | 10,715 (49.6) | ||
| 4-6 days per week | 221 (6.8) | 47,737 (9.3) | 299 (6.3) | 1271 (5.9) | ||
| 1-3 days per week | 932 (28.4) | 160,357 (31.5) | 1297 (27.5) | 5711 (26.5) | ||
| <1 day per week | 1707 (52.0) | 205,176 (40.3) | 895 (18.9) | 3878 (18.0) | ||
| Family history of CVD (%) | 847 (25.8) | 104,208 (20.5) | <.001 | 717 (15.2) | 1939 (9.0) | <.001 |
| Health index (%) | <.001 | <.001 | ||||
| 0 | 1921 (58.6) | 306,564 (60.2) | 1076 (22.8) | 6746 (31.3) | ||
| 1 | 1017 (31.0) | 165,952 (32.6) | 161 (34.2) | 8370 (38.8) | ||
| 2 | 283 (8.6) | 32,010 (6.3) | 1214 (25.7) | 4553 (21.1) | ||
| ≥3 | 59 (1.8) | 4906 (0.9) | 819 (17.3) | 1906 (8.8) | ||
| Chronic diseases | ||||||
| COPD/asthma (%) | 172 (5.2) | 15,125 (3.0) | <.001 | 927 (19.6) | 2487 (11.5) | <.001 |
| Hypertension (%) | 1047 (31.9) | 173,405 (34.0) | .01 | 2718 (57.6) | 11,825 (54.8) | <.001 |
| CHD (%) | 161 (4.9) | 15,311 (3.0) | <.001 | 1220 (25.8) | 3228 (15.0) | <.001 |
| Stroke (%) | 116 (3.5) | 8768 (1.7) | <.001 | 378 (8.0) | 1057 (4.9) | <.001 |
| Diabetes (%) | 23 3(7.1) | 30,066 (5.9) | .004 | 1078 (22.8) | 3828 (17.7) | <.001 |
| Cancer (%) | 43 (1.3) | 2535 (0.5) | <.001 | 426 (9.0) | 1163 (5.4) | <.001 |
Abbreviation: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); CHD, coronary heart disease; CKB, China Kadoorie Biobank; CVD, cardiovascular diseases; COPD, chronic obstructive pulmonary disease; DFTJ, Dongfeng-Tongji; NA, data not available.
a
Data are shown as mean ± standard deviation for continuous variables, or percentage for categorical variables.
b
P values were calculated by Student t-test for continuous variables or χ2 test for categorical variables.
c
MET hours/day: metabolic equivalent of task value for a day's work and leisure activities for both farmers and non-farmer.