Table 2.
Association of Alu and LINE-1 methylation with the characteristics of the study subjects, in combination as well as within each of the five studies
| Variable |
Alu |
LINE-1 |
|||||||
|---|---|---|---|---|---|---|---|---|---|
| N | %5mCa | 95% CIa | β (95% CI)a | N | %5mCa | 95% CIa | β (95% CI)a | ||
| All studies | |||||||||
| Age, years | |||||||||
| <48 | 285 | 26.1 | 25.8–26.4 | 264 | 77.2 | 76.7–77.8 | |||
| 48–63 | 279 | 26.0 | 25.8–26.2 | 271 | 77.4 | 77.0–77.8 | |||
| 64–69 | 314 | 26.0 | 25.8–26.2 | 307 | 77.2 | 76.8–77.6 | |||
| 70–74 | 267 | 25.9 | 25.7–26.1 | 263 | 77.1 | 76.7–77.6 | |||
| ≥75 | 320 | 25.9 | 25.7–26.1 | −0.011 (−0.020 to −0.001)b | 313 | 77.2 | 76.8–77.6 | 0.003 (−0.016 to 0.021)b | |
| Gender | |||||||||
| Female | 206 | 26.3 | 26.1–26.6 | 202 | 76.6 | 76.1–77.0 | |||
| Male | 1238 | 25.9 | 25.8–26.0 | −0.385 (−0.665 to −0.104) | 1216 | 77.4 | 77.2–77.5 | 0.796 (0.261 to 1.330) | |
| BMI, kg/m2 | |||||||||
| <25.3 | 413 | 25.8 | 25.7–25.9 | 408 | 78.0 | 77.8–78.3 | |||
| 25.3–28.5 | 415 | 25.8 | 25.6–25.9 | 415 | 78.3 | 78.1–78.5 | |||
| ≥28.6 | 410 | 25.9 | 25.7–26.0 | 0.012 (−0.005 to 0.030)b | 408 | 78.2 | 78.0–78.4 | 0.003 (−0.033 to 0.040)b | |
| Alcohol drinking | |||||||||
| Non-drinker | 609 | 26.1 | 26.0–26.3 | 604 | 77.2 | 76.9–77.4 | |||
| Ever drinker | 717 | 25.9 | 25.8–26.0 | −0.214 (−0.415 to −0.013) | 700 | 77.1 | 76.9–77.3 | −0.053 (−0.430 to 0.323) | |
| Smoking status | |||||||||
| Non-smoker | 519 | 26.0 | 25.8–26.1 | 504 | 77.2 | 77.0–77.5 | |||
| Former smoker | 665 | 26.0 | 25.9–26.1 | 659 | 77.3 | 77.0–77.5 | |||
| Current smoker | 257 | 26.0 | 25.8–26.2 | 252 | 77.2 | 76.7–77.6 | |||
| Trend statistics | 0.018 (−0.107 to 0.143) | −0.025 (−0.263 to 0.214) | |||||||
| Study 1 | |||||||||
| Age, years | |||||||||
| <48 | 0 | NA | NA | 0 | NA | NA | |||
| 48–63 | 63 | 26.5 | 26.2–26.7 | 63 | 77.4 | 77.0–77.9 | |||
| 64–69 | 199 | 26.5 | 26.3–26.6 | 196 | 76.9 | 76.6–77.1 | |||
| 70–74 | 185 | 26.3 | 26.1–26.4 | 186 | 76.8 | 76.5–77.1 | |||
| ≥75 | 261 | 26.2 | 26.1–26.3 | −0.022 (−0.034 to −0.010)b | 258 | 76.9 | 76.6–77.1 | −0.011 (−0.033 to 0.010)b | |
| Gender | |||||||||
| Female | 0 | NA | NA | 0 | NA | NA | |||
| Male | 708 | 26.3 | 26.2–26.4 | NA | 703 | 76.9 | 76.8–77.0 | NA | |
| BMI, kg/m2 | |||||||||
| <25.3 | 160 | 26.3 | 26.1–26.4 | 156 | 76.9 | 76.6–77.2 | |||
| 25.3–28.5 | 251 | 26.3 | 26.1–26.4 | 252 | 77.0 | 76.7–77.2 | |||
| ≥28.6 | 297 | 26.4 | 26.2–26.5 | 0.021 (0.001 to 0.041)b | 295 | 76.9 | 76.6–77.1 | 0.005 (−0.032 to 0.042)b | |
| Alcohol drinking | |||||||||
| Non-drinker | 383 | 26.3 | 26.2–26.5 | 381 | 76.7 | 76.5–76.9 | |||
| Ever drinker | 271 | 26.3 | 26.2–26.4 | −0.023 (−0.188 to 0.143) | 272 | 76.9 | 76.7–77.1 | 0.239 (−0.037 to 0.515) | |
| Smoking status | |||||||||
| Non-smoker | 208 | 26.3 | 26.2–26.5 | 206 | 76.7 | 76.5–77.0 | |||
| Former smoker | 473 | 26.3 | 26.2–26.4 | 470 | 76.9 | 76.8–77.1 | |||
| Current smoker | 27 | 26.2 | 25.8–26.6 | 27 | 77.4 | 76.7–78.2 | |||
| Trend statistics | −0.015 (−0.173 to 0.143) | 0.252 (−0.033 to 0.536) | |||||||
| Study 2 | |||||||||
| Age, years | |||||||||
| <48 | 41 | 25.0 | 24.6–25.5 | 40 | 79.4 | 78.4–80.4 | |||
| 48–63 | 141 | 25.1 | 24.8–25.3 | 141 | 80.5 | 79.9–81.0 | |||
| 64–69 | 109 | 24.9 | 24.7–25.2 | 108 | 80.2 | 79.6–80.9 | |||
| 70–74 | 75 | 24.9 | 24.6–25.3 | 75 | 80.2 | 79.5–80.9 | |||
| ≥75 | 55 | 25.4 | 25.0–25.8 | 0.004 (−0.009 to 0.017)b | 55 | 80.2 | 79.4–81.1 | 0.017 (−0.012 to 0.047)b | |
| Gender | |||||||||
| Female | 149 | 25.2 | 25.0–25.4 | 148 | 79.6 | 79.1–80.1 | |||
| Male | 272 | 25.0 | 24.8–25.1 | −0.201 (−0.486 to 0.084) | 271 | 80.6 | 80.2–80.9 | 0.951 (0.304 to 1.597) | |
| BMI, kg/m2 | |||||||||
| <25.3 | 206 | 25.1 | 24.9–25.3 | 205 | 80.1 | 79.6–80.5 | |||
| 25.3–28.5 | 126 | 25.0 | 24.7–25.2 | 125 | 80.4 | 79.8–81.0 | |||
| ≥28.6 | 88 | 25.0 | 24.7–25.3 | −0.013 (−0.051 to 0.025)b | 88 | 80.3 | 79.6–81.0 | −0.024 (−0.110 to 0.062)b | |
| Alcohol drinking | |||||||||
| Non-drinker | 138 | 25.2 | 24.9–25.5 | 138 | 80.4 | 79.8–81.0 | |||
| Ever drinker | 283 | 25.0 | 24.8–25.2 | −0.227 (−0.567 to 0.112) | 281 | 80.2 | 79.8–80.6 | −0.218 (−0.991 to 0.554) | |
| Smoking status | |||||||||
| Non-smoker | 169 | 24.9 | 24.7–25.1 | 168 | 80.3 | 79.7–80.8 | |||
| Former smoker | 143 | 25.1 | 24.9–25.4 | 143 | 80.3 | 79.7–80.8 | |||
| Current smoker | 109 | 25.2 | 24.9–25.5 | 108 | 80.1 | 79.5–80.8 | |||
| Trend statistics | 0.136 (−0.046 to 0.317) | −0.053 (−0.466 to 0.361) | |||||||
| Study 3 | |||||||||
| Age, years | |||||||||
| <48 | 164 | 27.2 | 26.7–27.7 | 150 | 71.8 | 70.8–72.7 | |||
| 48–63 | 36 | 26.7 | 25.6–27.8 | 31 | 71.3 | 69.2–73.4 | |||
| 64–69 | 3 | 26.8 | 23.0–30.7 | 3 | 72.7 | 65.9–79.4 | |||
| 70–74 | 2 | 27.4 | 22.7–32.1 | 2 | 69.5 | 61.1–77.8 | |||
| ≥75 | 0 | NA | NA | −0.027 (−0.069 to 0.014)b | 0 | NA | NA | 0.007 (−0.071 to 0.084)b | |
| Gender | |||||||||
| Female | 57 | 27.6 | 26.8–28.5 | 54 | 71.4 | 69.8–73.0 | |||
| Male | 148 | 26.9 | 26.3–27.4 | −0.782 (−1.811 to 0.247) | 132 | 71.8 | 70.8–72.8 | 0.397 (−1.500 to 2.294) | |
| BMI, kg/m2 | |||||||||
| <25.3 | NA | NA | NA | NA | NA | NA | |||
| 25.3–28.5 | NA | NA | NA | NA | NA | NA | |||
| ≥28.6 | NA | NA | NA | NA | NA | NA | NA | NA | |
| Alcohol drinking | |||||||||
| Non-drinker | 74 | 27.6 | 26.7–28.4 | 71 | 72.3 | 70.8–73.8 | |||
| Ever drinker | 129 | 26.8 | 26.2–27.4 | −0.756 (−1.831 to 0.319) | 113 | 71.2 | 70.0–72.3 | −1.164 (−3.128 to 0.800) | |
| Smoking status | |||||||||
| Non-smoker | 94 | 27.2 | 26.5–27.8 | 82 | 72.0 | 70.7–73.3 | |||
| Former smoker | 32 | 26.9 | 25.7–28.1 | 29 | 71.2 | 69.0–73.4 | |||
| Current smoker | 79 | 27.1 | 26.3–27.8 | 75 | 71.5 | 70.2–72.9 | |||
| Trend statistics | −0.051 (−0.554 to 0.451) | −0.232 (−1.171 to 0.707) | |||||||
| Study 4 | |||||||||
| Age, years | |||||||||
| <48 | 43 | 25.8 | 25.5–26.0 | 43 | 78.8 | 78.5–79.1 | |||
| 48–63 | 19 | 26.0 | 25.7–26.3 | 19 | 78.9 | 78.4–79.3 | |||
| 64–69 | 0 | NA | NA | 0 | NA | NA | |||
| 70–74 | 0 | NA | NA | 0 | NA | NA | |||
| ≥75 | 0 | NA | NA | 0.014 (−0.010 to 0.039)b | 0 | NA | NA | −0.006 (−0.040 to 0.027)b | |
| Gender | |||||||||
| Female | 0 | NA | NA | 0 | NA | NA | |||
| Male | 62 | 25.8 | 25.7–26.0 | NA | 62 | 78.8 | 78.6–79.1 | NA | |
| BMI, kg/m2 | |||||||||
| <25.3 | 21 | 25.7 | 25.4–26.0 | 21 | 79.1 | 78.7–79.5 | |||
| 25.3–28.5 | 26 | 25.8 | 25.5–26.1 | 26 | 78.8 | 78.4–79.2 | |||
| ≥28.6 | 15 | 26.0 | 25.6–26.4 | 0.035 (−0.034 to 0.104)b | 15 | 78.4 | 77.9–78.9 | −0.108 (−0.201 to −0.016)b | |
| Alcohol drinking | |||||||||
| Non-drinker | NA | NA | NA | NA | NA | NA | |||
| Ever drinker | NA | NA | NA | NA | NA | NA | NA | NA | |
| Smoking status | |||||||||
| Non-smoker | 20 | 26.2 | 25.9–26.5 | 20 | 78.8 | 78.3–79.2 | |||
| Former smoker | 15 | 25.5 | 25.1–25.8 | 15 | 78.8 | 78.3–79.4 | |||
| Current smoker | 24 | 25.9 | 25.6–26.1 | 24 | 78.9 | 78.4–79.3 | |||
| Trend statistics | −0.162 (−0.380 to 0.055) | 0.057 (−0.259 to 0.373) | |||||||
| Study 5 | |||||||||
| Age, years | |||||||||
| <48 | 31 | 24.9 | 24.6–25.3 | 31 | 79.1 | 77.9–80.2 | |||
| 48–63 | 17 | 24.8 | 24.3–25.3 | 17 | 78.1 | 76.6–79.7 | |||
| 64–69 | 0 | NA | NA | 0 | NA | NA | |||
| 70–74 | 0 | NA | NA | 0 | NA | NA | |||
| ≥75 | 0 | NA | NA | 0.006 (−0.025 to 0.037)b | 0 | NA | NA | −0.061 (−0.161 to 0.039)b | |
| Gender | |||||||||
| Female | 0 | NA | NA | 0 | NA | NA | |||
| Male | 48 | 24.9 | 24.6–25.2 | NA | 48 | 78.7 | 77.8–79.7 | NA | |
| BMI, kg/m2 | |||||||||
| <25.3 | 26 | 25.0 | 24.6–25.4 | 26 | 77.6 | 76.4–78.8 | |||
| 25.3–28.5 | 12 | 24.6 | 24.1–25.2 | 12 | 79.7 | 77.9–81.5 | |||
| ≥28.6 | 10 | 24.8 | 24.1–25.5 | −0.093 (−0.198 to 0.011)b | 10 | 80.5 | 78.5–82.5 | 0.386 (0.058 to 0.714)b | |
| Alcohol drinking | |||||||||
| Non-drinker | 14 | 25.4 | 24.8–25.9 | 14 | 77.6 | 75.8–79.5 | |||
| Ever drinker | 34 | 24.7 | 24.3–25.0 | −0.687 (−1.379 to 0.005) | 34 | 79.2 | 78.0–80.3 | 1.557 (−0.722 to 3.836) | |
| Smoking status | |||||||||
| Non-smoker | 28 | 24.9 | 24.5–25.3 | 28 | 79.1 | 77.9–80.3 | |||
| Former smoker | 2 | 25.3 | 23.8–26.8 | 2 | 74.5 | 70.0–79.1 | |||
| Current smoker | 18 | 24.8 | 24.3–25.3 | 18 | 78.6 | 77.1–80.2 | |||
| Trend statistics | −0.027 (−0.341 to 0.287) | −0.290 (−1.300 to 0.719) | |||||||
%5mC, percentage of 5-methyl cytosine; NA, not available.
aAdjusted for age, gender and study.
bβ for age and BMI were obtained using continuous variables.