Table 1 Baseline characteristics of the study population.
Variables | Total (N = 2,289,347) |
|---|---|
1. Demographic factors | |
Age, years, mean ± SD | 62.41 ± 8.25 |
Age group, No. (%) | |
50–54 years | 471,472 (20.59) |
55–59 years | 496,721 (21.70) |
60–64 years | 514,585 (22.48) |
65–69 years | 291,718 (12.74) |
70–74 years | 310,752 (13.57) |
75–79 years | 125,953 (5.50) |
≥ 80 years | 78,146 (3.41) |
Income, No. (%) | |
Q1 (lowest) | 520,295 (22.73) |
Q2 | 404,520 (17.67) |
Q3 | 540,526 (23.61) |
Q4 (highest) | 824,006 (35.99) |
2. Systemic comorbidities | |
Hypertension, No. (%) | |
No | 1,331,201 (58.15) |
Yes | 958,146 (41.85) |
Diabetes mellitus, No. (%) | |
No | 1,955,305 (85.41) |
Yes | 334,042 (14.59) |
Dyslipidemia, No. (%) | |
No | 1,624,088 (70.94) |
Yes | 665,259 (29.06) |
Stroke, No. (%) | |
No | 2,253,049 (98.41) |
Yes | 36,298 (1.59) |
Heart diseases, No. (%) | |
No | 2,196,562 (95.95) |
Yes | 92,785 (4.05) |
Chronic kidney disease, No. (%) | |
No | 2,100,209 (91.74) |
Yes | 189,138 (8.26) |
3. Behavioral factors | |
Smoking history, No. (%) | |
Never smoked | 2,210,674 (96.56) |
Former smoker | 25,971 (1.13) |
Current smoker | 52,702 (2.30) |
Drinking habit, No. (%) | |
None | 1,987,784 (86.83) |
Mild | 283,589 (12.39) |
Heavy | 17,974 (0.79) |
Regular physical activity, No. (%) | |
No | 1,796,638 (78.48) |
Yes | 492,709 (21.52) |
Body mass index, No (%) | |
< 18.5 kg/m2 | 54,225 (2.37) |
18.5 to < 23 kg/m2 | 840,944 (36.73) |
23 to < 25 kg/m2 | 590,348 (25.79) |
25 to < 30 kg/m2 | 705,413 (30.81) |
≥ 30 kg/m2 | 98,417 (4.30) |
4. Reproductive factors | |
Age at menarche, mean ± SD | 16.19 ± 2.02 |
Age at menarche in group, No. (%) | |
< 14 years | 142,577 (6.23) |
14–15 years | 734,166 (32.07) |
16–17 years | 875,342 (38.24) |
≥ 18 years | 537,262 (23.47) |
Age at menopause, mean ± SD | 50.63 ± 3.91 |
Age at menopause in group, No. (%) | |
< 45 years | 120,874 (5.28) |
45–49 years | 529,786 (23.14) |
50–54 years | 1,333,631 (58.25) |
≥ 55 years | 305,056 (13.33) |
Parity, No. (%) | |
Nulliparous | 40,211 (1.76) |
1 child | 186,256 (8.14) |
≥ 2 children | 2,062,880 (90.11) |
Duration of breastfeeding, No. (%) | |
Never | 191,413 (8.36) |
< 0.5 year | 208,816 (9.12) |
0.5 to < 1 year | 426,428 (18.63) |
≥ 1 year | 1,462,690 (63.89) |
Hormone replacement therapy, No. (%) | |
Never used | 1,834,474 (80.13) |
< 2 years | 202,796 (8.86) |
2 to < 5 years | 86,281 (3.77) |
≥ 5 years | 70,579 (3.08) |
Unknown | 95,217 (4.16) |
Oral contraceptive pill use, No. (%) | |
Never used | 1,838,861 (80.32) |
< 1 year | 201,721 (8.81) |
≥ 1 year | 134,661 (5.88) |
Unknown | 114,104 (4.98) |
