Table 1.
Characteristics of participants by HTN status
| Characteristics | HTN | Without HTN | Stage 1 HTN | Stage 2 HTN | P values |
|---|---|---|---|---|---|
| (n = 27,004) | (n = 20,497) | (n = 12,552) | (n = 14,452) | ||
| Age, years, mean (SD) | 54.2 (12.7) | 45.5 (13.8) | 50.8 (12.9) | 57.1 (11.7) | < 0.001 |
| SBP, mm Hg, mean (SD) | 143.1 (16.2) | 116.1 (8.4) | 130.8 (6.2) | 153.7 (14.7) | < 0.001 |
| DBP, mm Hg, mean (SD) | 83.9 (9.6) | 70.0 (6.4) | 80.2 (6.2) | 87.1 (10.8) | < 0.001 |
| Air pollutants, µg/m 3 (SD) | |||||
| PM2.5 | 54.5 (23.1) | 51.9 (22.7) | 54.1 (23.1) | 54.9 (23.1) | < 0.001 |
|
10.0 (3.9) | 9.6 (3.9) | 10.0 (3.9) | 10.1 (3.9) | < 0.001 |
|
11.1 (5.4) | 10.3 (5.4) | 11.0 (5.4) | 11.3 (5.4) | < 0.001 |
|
7.7 (3.3) | 7.2 (3.4) | 7.6 (3.4) | 7.8 (3.4) | < 0.001 |
| BC | 2.7 (0.9) | 2.6 (0.9) | 2.7 (0.9) | 2.7 (0.9) | < 0.001 |
| OM | 13.3 (5.4) | 12.7 (5.3) | 13.2 (5.4) | 13.4 (5.4) | < 0.001 |
| Dietary score | |||||
| DASH | 20.0 (4.6) | 20.6 (4.7) | 20.2 (4.6) | 19.9 (4.6) | < 0.001 |
| AMED | 24.1 (4.3) | 24.2 (4.2) | 24.2 (4.3) | 24.0 (4.3) | 0.211 |
| Fruits | 2.9 (1.4) | 3.1 (1.4) | 3.0 (1.4) | 2.8 (1.4) | < 0.001 |
| Vegetables | 3.1 (1.4) | 3.1 (1.4) | 3.1 (1.4) | 3.1 (1.4) | 0.054 |
| Dairy | 2.3 (1.7) | 2.6 (1.8) | 2.3 (1.7) | 2.2 (1.7) | < 0.001 |
| Whole grains | 2.8 (1.7) | 2.7 (1.6) | 2.7 (1.6) | 2.8 (1.7) | < 0.001 |
| Legumes and nuts | 3.0 (1.4) | 3.1 (1.4) | 3.0 (1.4) | 2.9 (1.4) | < 0.001 |
| Red meat | 3.1 (1.4) | 2.9 (1.4) | 3.0 (1.4) | 3.2 (1.4) | < 0.001 |
| Sodium | 2.9 (1.4) | 3.1 (1.4) | 3.0 (1.4) | 2.9 (1.4) | < 0.001 |
| MUFA: SFA | 3.1 (1.4) | 2.9 (1.4) | 3.0 (1.4) | 3.2 (1.4) | < 0.001 |
| Fish | 2.9 (1.4) | 3.1 (1.4) | 3.0 (1.4) | 2.8 (1.4) | < 0.001 |
| Alcohol | 3.3 (0.8) | 3.3 (0.7) | 3.3 (0.8) | 3.3 (0.9) | < 0.001 |
| Sex (%) | < 0.001 | ||||
| Male | 14,068 (52.1) | 8066 (39.4) | 6630 (52.8) | 7438 (51.5) | |
| Female | 12,936 (47.9) | 12,431 (60.6) | 5922 (47.2) | 7014 (48.5) | |
| Education level (%) | < 0.001 | ||||
| Illiteracy | 7818 (29.0) | 4102 (20.0) | 3038 (24.2) | 4780 (33.1) | |
| Primary | 5807 (21.5) | 3786 (18.5) | 2586 (20.6) | 3221 (22.3) | |
| Junior high | 8428 (31.2) | 6882 (33.6) | 4240 (33.8) | 4188 (29.0) | |
| Senior high | 3417 (12.7) | 3189 (15.6) | 1761 (14.0) | 1656 (11.5) | |
| College and higher | 1534 (5.6) | 2538 (12.3) | 927 (7.4) | 607 (4.1) | |
| Marital status (%) | < 0.001 | ||||
| Married or cohabiting | 25,120 (93.0) | 18,735 (91.4) | 11,691 (93.1) | 13,429 (92.9) | |
| Widowed | 939 (3.5) | 351 (1.7) | 291 (2.3) | 648 (4.5) | |
| Separated or divorced | 190 (0.7) | 162 (0.8) | 87 (0.7) | 103 (0.7) | |
| Never married | 755 (2.8) | 1249 (6.1) | 483 (3.9) | 272 (1.9) | |
| Annual family income, CYN (%) | < 0.001 | ||||
| < 20,000 | 6118 (22.7) | 3644 (17.8) | 2503 (19.9) | 3615 (25.0) | |
| 20,000~49,999 | 9394 (34.8) | 6940 (33.9) | 4475 (35.7) | 4919 (34.0) | |
| ≥ 50,000 | 7198 (26.7) | 6740 (32.9) | 3677 (29.3) | 3521 (24.4) | |
| Unknown | 4294 (15.8) | 3173 (15.4) | 1897 (15.1) | 2397 (16.6) | |
| BMI, kg/m 2 (%) | < 0.001 | ||||
| 18.5~23.9 | 11,495 (42.6) | 12,030 (58.7) | 5817 (46.3) | 5678 (39.3) | |
| < 18.5 | 778 (2.9) | 1225 (6.0) | 393 (3.1) | 385 (2.7) | |
| 24.0~27.9 | 10,285 (38.1) | 5852 (28.6) | 4625 (36.9) | 5660 (39.2) | |
| ≥ 28.0 | 4446 (16.4) | 1390 (6.7) | 1717 (13.7) | 2729 (18.8) | |
| Smoking status (%) | < 0.001 | ||||
| Never | 17,154 (63.5) | 14,792 (72.2) | 7938 (63.2) | 9216 (63.8) | |
| Smoking or quit smoking | 9850 (36.5) | 5705 (27.8) | 4614 (36.8) | 5236 (36.2) | |
| Passive smoking (%) | < 0.001 | ||||
| Yes | 17,931 (66.4) | 13,930 (68.0) | 8560 (68.2) | 9371 (64.8) | |
| No | 9073 (33.6) | 6567 (32.0) | 3992 (31.8) | 5081 (35.2) | |
| Alcohol consumption (%) | < 0.001 | ||||
| Never | 16,579 (61.4) | 13,600 (66.4) | 7537 (60.1) | 9042 (62.6) | |
| ≤ 3 times/ month | 4306 (16.0) | 4062 (19.8) | 2229 (17.8) | 2077 (14.4) | |
| 1–4 times/ week | 2623 (9.7) | 1591 (7.8) | 1333 (10.6) | 1290 (8.9) | |
| ≥ 5 times/ week | 3496 (13.0) | 1244 (6.0) | 1453 (11.5) | 2043 (14.1) | |
| Household solid-fuel use (%) | < 0.001 | ||||
| Yes | 10,637 (39.4) | 6926 (33.8) | 4583 (36.5) | 6054 (41.9) | |
| No | 16,367 (60.6) | 13,571 (66.2) | 7969 (63.5) | 8398 (58.1) | |
| Physical activity (%) | < 0.001 | ||||
| Low | 6439 (23.8) | 4720 (23.0) | 2960 (23.6) | 3479 (24.1) | |
| Moderate | 6498 (24.1) | 5364 (26.2) | 3074 (24.5) | 3424 (23.7) | |
| High | 14,067 (52.1) | 10,413 (50.8) | 6518 (51.9) | 7549 (52.2) | |
| HTN family history (%) | 0.084 | ||||
| Yes | 7794 (28.9) | 6065 (29.6) | 3670 (29.2) | 4124 (28.5) | |
| No | 19,210 (71.1) | 14,432 (70.4) | 8882 (70.8) | 10,328 (71.5) | |
| Residence (%) | < 0.001 | ||||
| Urban | 10,498 (38.9) | 9064 (44.2) | 5090 (40.6) | 5408 (37.4) | |
| Rural | 16,506 (61.1) | 11,433 (55.8) | 7462 (59.4) | 9044 (62.6) | |
| Region (%) | < 0.001 | ||||
| North | 4366 (16.2) | 2496 (12.2) | 1916 (15.3) | 2450 (17.0) | |
| Northeast | 3060 (11.3) | 1954 (9.4) | 1423 (11.3) | 1637 (11.3) | |
| East | 7305 (27.1) | 5403 (26.4) | 3498 (27.9) | 3807 (26.3) | |
| Central | 3571 (13.2) | 2475 (12.1) | 1644 (13.1) | 1927 (13.3) | |
| Southwest | 3408 (12.6) | 3028 (14.8) | 1546 (12.3) | 1862 (12.9) | |
| Northwest | 2614 (9.7) | 2484 (12.1) | 1191 (9.5) | 1423 (9.9) | |
| South | 2680 (9.9) | 2657 (13.0) | 1334 (10.6) | 1346 (9.3) | |
| Outdoor time, mins/day (%) | < 0.001 | ||||
| Quintile 1 [0,75] | 5118 (19.0) | 4552 (22.2) | 2498 (19.9) | 2620 (18.1) | |
| Quintile 2 [76,142] | 5136 (19.0) | 4038 (19.7) | 2416 (19.3) | 2720 (18.8) | |
| Quintile 3 [143,225] | 5493 (20.3) | 4090 (20.0) | 2488 (19.8) | 3005 (20.8) | |
| Quintile 4 [226,357] | 5334 (19.8) | 3705 (18.1) | 2380 (19.0) | 2954 (20.4) | |
| Quintile 5 [360,750] | 5923 (21.9) | 4112 (20.0) | 2770 (22.0) | 3153 (21.9) | |
Abbreviations: HTN, hypertension; SD, standard deviation; SBP, systolic blood pressure; DBP, diastolic blood pressure; PM2.5, fine particulate matter; 
, sulfate; 
, nitrate; 
, ammonium; BC, black carbon; OM, organic matter; DASH, dietary approaches to stop hypertension; AMED, alternative Mediterranean diet; MUFA: SFA, the ratio of monounsaturated to saturated fatty acids; BMI, body mass index
Note: Data were expressed as Mean (SD) for continuous variables and counts (%) for categorical variables. P values for the test of variance between participants with HTN and those without HTN were calculated