Table 1 Baseline population characteristics
Variables | Residence | Overall | |
|---|---|---|---|
Urban (N = 296) | Rural (N = 1459) | (N = 1755) | |
3-year average NDVI: mean (SD) (0.1 unit) | 4.44 (1.25) | 4.96 (0.83) | 4.88 (0.94) |
3-year average PM2.5: mean (SD) (10 μg/m3) | 4.91 (1.14) | 4.90 (1.60) | 4.90 (1.53) |
GDP per capita in 2012: mean (SD) (10,000 RMB) | 4.77 (4.85) | 4.27 (3.64) | 4.35 (3.87) |
Sex: n(%) Male | 127 (42.9) | 683 (46.8) | 810 (46.2) |
Age: mean (SD) | 84.6 (11.9) | 85.8 (12.3) | 85.6 (12.2) |
Schooling year: n(%) | |||
 No formal education | 168 (56.8) | 918 (62.9) | 1086 (61.9) |
 1–6 years education | 88 (29.7) | 417 (28.6) | 505 (28.8) |
  > 6 years education | 40 (13.5) | 124 (8.5) | 164 (9.3) |
Ethnicity: n(%) Han | 269 (90.9) | 1351 (92.6) | 1620 (92.3) |
Marriage: n(%) Currently married | 115 (38.9) | 563 (38.6) | 678 (38.6) |
Exercise: n(%) | |||
 Never | 238 (80.4) | 1199 (82.2) | 1437 (81.9) |
 Former | 4 (1.4) | 37 (2.5) | 41 (2.3) |
 Current | 54 (18.2) | 223 (15.3) | 277 (15.8) |
Smoking: n(%) | |||
 Never | 244 (82.4) | 1079 (74.0) | 1323 (75.4) |
 Former | 17 (5.7) | 128 (8.8) | 145 (8.3) |
  < 20 times/day | 21 (7.1) | 141 (9.7) | 162 (9.2) |
  ≥ 20 times/day | 14 (4.7) | 111 (7.6) | 125 (7.1) |
Alcohol: n(%) | |||
 Never | 245 (82.8) | 1123 (77.0) | 1368 (77.9) |
 Former | 20 (6.8) | 80 (5.5) | 100 (5.7) |
  ≤ 14 g/d(female) 28(male) | 9 (3.0) | 91 (6.2) | 100 (5.7) |
  > 14 g/d(female) 28(male) | 22 (7.4) | 165 (11.3) | 187 (10.7) |
TC: mean (SD) (mmol/L) | 4.30 (0.954) | 4.28 (0.981) | 4.29 (0.976) |
LDL-C: mean (SD) (mmol/L) | 2.43 (0.821) | 2.57 (0.821) | 2.54 (0.822) |
TG: median (P25-P75) (mg/dL) | 87 (61–118) | 70 (51–98) | 73 (52–102) |
HDL-C: mean (SD) (mg/dL) | 51.3 (15.2) | 49.8 (13.7) | 50.1 (14.0) |
Waist circumference: mean (SD) (centimeter) | 79.6 (11.4) | 79.7 (10.8) | 79.6 (10.9) |
Fasting glucose: median (P25-P75) (mg/dL) | 76 (54–91) | 80 (68–93) | 80 (67–92) |
SBP: mean (SD) (mmHg) | 141 (21.1) | 140 (23.1) | 141 (22.8) |
DBP: mean (SD) (mmHg) | 82.8 (11.2) | 80.8 (12.1) | 81.1 (11.9) |
Abdominal obesity: n(%) Yes | 107 (36.1) | 476 (32.6) | 583 (33.2) |
Elevated fasting glucose: n(%) Yes | 41 (13.9) | 266 (18.2) | 307 (17.5) |
Hypertension: n(%) Yes | 225 (76.0) | 1060 (72.7) | 1285 (73.2) |
Hypertriglyceridemia: n(%) Yes | 40 (13.5) | 117 (8.0) | 157 (8.9) |
Reduced HDL-C: n(%) Yes | 112 (37.8) | 567 (38.9) | 679 (38.7) |
Mets: n (%) Yes | 67 (22.6) | 303 (20.8) | 370 (21.1) |