Table 2 Mean relative telomere length by characteristics of women, the Singapore Chinese Health Study
Variables | Age at blood draw | Number | Telomere length (95% CI) | P 1 |
|---|---|---|---|---|
Age at sample collection, years | ||||
 45 to < 55 | 52.5 | 2452 | 1.11 (1.10, 1.12) | < 0.0001 |
 55 to < 60 | 56.8 | 3528 | 1.09 (1.08, 1.09) | |
 60 to < 65 | 62.0 | 3173 | 1.04 (1.03, 1.05) | |
 ≥ 65 | 70.9 | 5152 | 0.98 (0.97, 0.99) | |
Body mass index, kg/m2 | ||||
 < 18.5 | 63.6 | 1016 | 1.04 (1.02, 1.05) | 0.21 |
 18.5 to < 23.0 | 61.8 | 5859 | 1.05 (1.04, 1.05) | |
 23.0 to < 27.5 | 62.6 | 5716 | 1.05 (1.04, 1.05) | |
 ≥ 27.5 | 62.3 | 1714 | 1.04 (1.03, 1.05) | |
Level of education | ||||
 No formal education | 66.4 | 4580 | 1.05 (1.04, 1.06) | 0.16 |
 Primary school | 61.6 | 6034 | 1.04 (1.04, 1.05) | |
 Secondary school and above | 58.3 | 3691 | 1.04 (1.03, 1.05) | |
Dialect group | ||||
 Cantonese | 62.5 | 7519 | 1.04 (1.04, 1.05) | 0.08 |
 Hokkien | 62.0 | 6786 | 1.05 (1.04, 1.05) | |
Alcohol consumption, drinks/week | ||||
 None | 62.5 | 12,788 | 1.04 (1.04, 1.05) | 0.41 |
 < 7 | 60.6 | 1331 | 1.05 (1.04, 1.06) | |
 ≥ 7 | 62.0 | 186 | 1.06 (1.03, 1.09) | |
Physical activity (weekly) | ||||
 No | 62.4 | 10,421 | 1.04 (1.04, 1.05) | 0.71 |
 Yes | 61.9 | 3884 | 1.04 (1.04, 1.05) | |
Smoking status | ||||
 Never | 61.8 | 13,053 | 1.04 (1.04, 1.05) | 0.87 |
 Former | 68.3 | 570 | 1.04 (1.02, 1.06) | |
 Current | 66.7 | 682 | 1.04 (1.03, 1.06) | |
Age when period became regular | ||||
 < 13 | 59.1 | 1988 | 1.04 (1.04, 1.05) | 0.77 |
 13–14 | 61.5 | 5152 | 1.04 (1.04, 1.05) | |
 15–16 | 63.5 | 4578 | 1.05 (1.04, 1.05) | |
 ≥ 17 | 64.7 | 2087 | 1.05 (1.04, 1.05) | |
 Never regular | 61.7 | 500 | 1.06 (1.04, 1.08) | |
Age at first live birth | ||||
 < 20.0 | 65.6 | 2420 | 1.05 (1.04, 1.06) | 0.42 |
 21.0–25.0 | 62.5 | 5357 | 1.04 (1.04, 1.05) | |
 26.0–30.0 | 60.8 | 3962 | 1.04 (1.03, 1.05) | |
 ≥ 31 | 61.0 | 1526 | 1.05 (1.04, 1.06) | |
 Nulliparous | 61.3 | 1040 | 1.04 (1.03, 1.06) | |
Number of live births | ||||
 0 | 61.2 | 1027 | 1.04 (1.03, 1.05) | 0.07 |
 1–2 | 59.3 | 4327 | 1.04 (1.03, 1.05) | |
 3–4 | 61.3 | 5748 | 1.04 (1.04, 1.05) | |
 ≥ 5 | 68.6 | 3158 | 1.05 (1.05, 1.06) | |
Menopausal status | ||||
 Premenopausal | 52.6 | 955 | 1.03 (1.02, 1.05) | 0.09 |
 Postmenopausal | 63.0 | 13,350 | 1.05 (1.04, 1.05) | |
Age at menopause | ||||
 ≤ 49 | 69.4 | 2425 | 1.05 (1.04, 1.06) | 0.97 |
 50–54 | 68.8 | 3376 | 1.04 (1.04, 1.05) | |
 ≥ 55 | 57.7 | 8504 | 1.04 (1.04, 1.05) | |
Family history of breast cancer | ||||
 No | 62.3 | 14,065 | 1.04 (1.04, 1.05) | 0.20 |
 Yes | 60.6 | 240 | 1.06 (1.03, 1.09) | |
Use of hormone therapy | ||||
 Never | 63.0 | 11,890 | 1.06 (1.05, 1.08) | 0.82 |
 Ever | 59.6 | 1602 | 1.04 (1.03, 1.05) | |
 Current | 57.4 | 813 | 1.04 (1.04, 1.05) | |
Use of oral contraceptive | ||||
 Never | 63.2 | 9888 | 1.05 (1.04, 1.05) | 0.23 |
 Former/current | 60.2 | 4417 | 1.04 (1.03, 1.05) | |
Sleeping hours | ||||
 ≤ 6 h | 63.2 | 4871 | 1.05 (1.04, 1.05) | 0.04 |
 7–8 h | 61.8 | 8503 | 1.04 (1.04, 1.05) | |
 ≥ 8 h | 62.4 | 931 | 1.03 (1.01, 1.04) | |