Table 1.
Baseline characteristics of the cohort with cut-off value 24 for MMSE scores, 1998–2018
| Cognitive impairment | ||||
|---|---|---|---|---|
| Overall | No | Yes | P value | |
| N = 9295 | N = 3852 | N = 5443 | ||
| Age (mean (SD)) | 88.35 (6.66) | 86.96 (6.13) | 89.34 (6.85) | < 0.001 |
| Age group (%) | < 0.001 | |||
| 80–90 | 5569 (59.91) | 2632 (68.33) | 2937 (53.96) | |
| 90–100 | 2749 (29.58) | 975 (25.31) | 1774 (32.59) | |
| 100 + | 977 (10.51) | 245 ( 6.36) | 732 (13.45) | |
| Follow-up time (mean (SD)) | 5.45 (4.95) | 7.16 (6.10) | 4.23 (3.46) | < 0.001 |
| Education (%) | < 0.001 | |||
| Illiteracy | 5760 (61.97) | 1992 (51.71) | 3768 (69.23) | |
| Literacy | 3535 (38.03) | 1860 (48.29) | 1675 (30.77) | |
| Gender (%) | < 0.001 | |||
| Female | 4663 (50.17) | 1477 (38.34) | 3186 (58.53) | |
| Male | 4632 (49.83) | 2375 (61.66) | 2257 (41.47) | |
| Marital status (%) | 0.193 | |||
| No | 106 ( 1.14) | 51 ( 1.32) | 55 ( 1.01) | |
| Yes | 9189 (98.86) | 3801 (98.68) | 5388 (98.99) | |
| Residence (%) | < 0.001 | |||
| Urban | 4266 (45.90) | 1865 (48.42) | 2401 (44.11) | |
| Rural | 5029 (54.10) | 1987 (51.58) | 3042 (55.89) | |
| Smoke (%) | < 0.001 | |||
| No | 5778 (62.16) | 2127 (55.22) | 3651 (67.08) | |
| Current | 2155 (23.18) | 1020 (26.48) | 1135 (20.85) | |
| Former | 1362 (14.65) | 705 (18.30) | 657 (12.07) | |
| Drink (%) | < 0.001 | |||
| No | 6171 (66.39) | 2406 (62.46) | 3765 (69.17) | |
| Current | 2156 (23.20) | 1002 (26.01) | 1154 (21.20) | |
| Former | 968 (10.41) | 444 (11.53) | 524 ( 9.63) | |
| Exercise (%) | < 0.001 | |||
| No | 5828 (62.70) | 2216 (57.53) | 3612 (66.36) | |
| Yes | 3467 (37.30) | 1636 (42.47) | 1831 (33.64) | |
| ADL disability (%) | < 0.001 | |||
| No | 8026 (86.35) | 3446 (89.46) | 4580 (84.14) | |
| Yes | 1269 (13.65) | 406 (10.54) | 863 (15.86) | |
| BMI (mean (SD)) | 19.99 (4.24) | 20.22 (4.24) | 19.82 (4.23) | < 0.001 |
| Hypertension (%) | 0.01 | |||
| No | 7805 (83.97) | 3189 (82.79) | 4616 (84.81) | |
| Yes | 1490 (16.03) | 663 (17.21) | 827 (15.19) | |
| Diabetes (%) | 0.223 | |||
| No | 9179 (98.75) | 3797 (98.57) | 5382 (98.88) | |
| Yes | 116 ( 1.25) | 55 ( 1.43) | 61 ( 1.12) | |
| Heart disease (%) | 0.036 | |||
| No | 8604 (92.57) | 3539 (91.87) | 5065 (93.06) | |
| Yes | 691 ( 7.43) | 313 ( 8.13) | 378 ( 6.94) | |
| Cerebrovascular disease (%) | 0.621 | |||
| No | 9004 (96.87) | 3736 (96.99) | 5268 (96.78) | |
| Yes | 291 ( 3.13) | 116 ( 3.01) | 175 ( 3.22) | |
| Respiratory disease (%) | 0.016 | |||
| No | 8235 (88.60) | 3376 (87.64) | 4859 (89.27) | |
| Yes | 1060 (11.40) | 476 (12.36) | 584 (10.73) | |
| Cancer (%) | 0.818 | |||
| No | 9271 (99.74) | 3841 (99.71) | 5430 (99.76) | |
| Yes | 24 ( 0.26) | 11 ( 0.29) | 13 ( 0.24) | |
| Comorbidity (%) | < 0.001 | |||
| No | 6397 (68.82) | 2552 (66.25) | 3845 (70.64) | |
| Yes | 2898 (31.18) | 1300 (33.75) | 1598 (29.36) | |
| Housework or childcare (%) | > 0.999 | |||
| No | 7078 (76.15) | 2933 (76.14) | 4145 (76.15) | |
| Yes | 2217 (23.85) | 919 (23.86) | 1298 (23.85) | |
| Main financial support (%) | < 0.001 | |||
| No | 3248 (34.94) | 1652 (42.89) | 1596 (29.32) | |
| Yes | 6047 (65.06) | 2200 (57.11) | 3847 (70.68) | |
| Living or being visited (%) | 0.31 | |||
| No | 704 (7.57) | 305 (7.92) | 399 (7.33) | |
| Yes | 8591 (92.43) | 3547 (92.08) | 5044 (92.67) | |
| MMSE scores (mean (SD)) | 27.64 (1.88) | 27.99 (1.78) | 27.40 (1.91) | < 0.001 |