Table 1.
Participant characteristics by residential areas
| Characteristics | Total, n (%) | Urban, n (%) | Rural, n (%) | χ2/Z | P value |
| Number of participants | 2644 | 1805 (68.2) | 839 (31.8) | ||
| Demographics | |||||
| Female | 1325 (50.1) | 965 (53.5) | 360 (42.9) | 25.52 | <0.001 |
| Age (years)*, median (IQR) | 70 (67–75) | 70 (67–75) | 70 (67–74) | 717 546.53 | 0.030 |
| Age groups | |||||
| 60–69 | 1230 (46.5) | 837 (46.4) | 393 (46.8) | 16.15 | <0.001 |
| 70–79 | 1128 (42.7) | 744 (41.2) | 384 (45.8) | ||
| ≥80 | 286 (10.8) | 224 (12.4) | 62 (7.4) | ||
| Education (years)*, median (IQR) | 9 (5–12) | 11 (9–15) | 2 (0–6) | 143 464.51 | <0.001 |
| Education (years) groups | |||||
| <6 | 940 (35.6) | 243 (13.5) | 697 (83.1) | 1229.32 | <0.001 |
| 6–12 | 1166 (44.1) | 1031 (57.1) | 135 (16.1) | ||
| >12 | 538 (20.3) | 531 (29.4) | 7 (0.8) | ||
| BMI level (n=2458) | |||||
| Underweight (<18.5) | 136 (5.5) | 71 (4.1) | 65 (9.2) | 32.14 | <0.001 |
| Normal (18.5–23.9) | 1234 (50.2) | 868 (49.6) | 366 (51.7) | ||
| Overweight (24.0–27.9) | 855 (34.8) | 629 (35.9) | 226 (31.9) | ||
| Obesity (≥28.0) | 233 (9.5) | 182 (10.4) | 51 (7.2) | ||
| Marital status | |||||
| Unmarried | 581 (22.0) | 276 (15.3) | 305 (36.4) | 148.19 | <0.001 |
| Social connections | |||||
| Living alone | 383 (14.5) | 147 (8.1) | 236 (28.1) | 184.67 | <0.001 |
| Having at least one sibling alive | 1818 (68.8) | 1371 (76.0) | 447 (53.3) | 137.13 | <0.001 |
| Having close friends | 1703 (64.4) | 1370 (75.9) | 333 (39.7) | 327.61 | <0.001 |
| Lifestyle behaviours | |||||
| Smoking (yes) | 793 (30.0) | 467 (25.9) | 326 (38.9) | 45.98 | <0.001 |
| Drinking (yes) | 655 (24.8) | 362 (20.1) | 293 (34.9) | 67.93 | <0.001 |
| Fresh fish consumption (yes) | 2190 (82.8) | 1644 (91.1) | 546 (65.1) | 272.30 | <0.001 |
| Physical activities (yes) | 2129 (80.5) | 1587 (87.9) | 542 (64.6) | 198.63 | <0.001 |
| Cognitive activities (yes) | 1777 (67.2) | 1471 (81.5) | 306 (36.5) | 526.84 | <0.001 |
| Comorbidities | |||||
| Insomnia (yes) | 1372 (51.9) | 868 (48.1) | 504 (60.1) | 32.94 | <0.001 |
| Overweight and obesity (yes)† | 1088 (44.3) | 811 (46.3) | 277 (39.1) | 10.65 | 0.001 |
| Hypertension (yes) | 1618 (61.2) | 1096 (60.7) | 522 (62.2) | 0.54 | 0.462 |
| Diabetes (yes) | 449 (17.0) | 354 (19.6) | 95 (11.3) | 27.92 | <0.001 |
*Continuous variables (eg, age and education).
†Percentage of overweight and obesity (yes) on the total of BMI level (n=2458).