Introduction
Methods
Subjects
Study design
Sleep study
Statistical analysis
Results
Comparison in demographic characteristics between AMI and control groups
Variables | AMI group (n = 314) | Control group (n = 559) | P value |
---|---|---|---|
Age (years) | 59 (51, 68) | 63 (55, 69) | 0.010 |
Men (n, %) | 250 (79.6%) | 361 (64.6%) | < 0.001 |
BMI (kg/m2) | 25.1 (22.8, 27.0) | 24.6 (22.8, 27.1) | 0.509 |
Residence in cities (n, %) | 239 (76.1%) | 393 (70.3%) | 0.070 |
Education level (n, %) | |||
Illiterate | 40 (12.7%) | 116 (20.8%) | 0.001 |
Elementary school | 58 (18.4%) | 138 (24.7%) | |
Junior high school | 101 (32.2%) | 140 (25.0%) | |
Senior high school and technical secondary school | 63 (20.1%) | 98 (17.5%) | |
Junior college or above | 52 (16.6%) | 67 (12.0%) | |
Diabetes (n, %) | 54 (17.2%) | 119 (21.3%) | 0.157 |
Hypertension (n, %) | 165 (52.5%) | 340 (60.8%) | 0.019 |
Dyslipidemia (n, %) | 20 (6.4%) | 28 (5.0%) | 0.440 |
Family history of CAD (n, %) | 15 (4.8%) | 16 (2.9%) | 0.181 |
Statins (n, %) | 11 (3.5%) | 33 (5.9%) | 0.147 |
Antiplatelet agents (n, %) | 21 (6.7%) | 51 (9.1%) | 0.249 |
β-blockers (n, %) | 13 (4.1%) | 42 (7.5%) | 0.059 |
ACEI or ARB (n, %) | 54 (17.2%) | 154 (27.5%) | 0.001 |
Smoking (n, %) | |||
Never | 102 (32.5%) | 276 (49.4%) | < 0.001 |
Former | 30 (9.6%) | 82 (14.7%) | |
< 20 cigarettes/day | 46 (14.6%) | 66 (11.8%) | |
≥ 20 cigarettes/day | 136 (43.3%) | 135 (24.2%) | |
Drinking (n, %) | |||
No | 154 (49.0%) | 349 (62.4%) | 0.002 |
1 to 3 times a month | 65 (20.7%) | 88 (15.7%) | |
1 to 6 times a week | 47 (15.0%) | 58 (10.4%) | |
At least once a day | 48 (15.3%) | 64 (11.4%) | |
Diet (n, %) | |||
Low-fat diet | 9 (2.9%) | 49 (8.8%) | < 0.001 |
Normal diet | 183 (58.3%) | 367 (65.7%) | |
High-fat diet | 122 (38.8%) | 143 (25.6%) | |
Regular exercise (n, %) | 85 (27.1%) | 200 (35.8%) | 0.009 |
Differences in sleep factors between AMI and control groups
Variables | AMI group (n = 314) | Control group (n = 559) | P value | |
---|---|---|---|---|
Timing of sleep | Before 22:00 | 88 (28.0%) | 213 (38.1%) | < 0.001 |
22:00 to 23:00 | 68 (21.7%) | 174 (31.1%) | ||
23:00 to 24:00 | 58 (18.5%) | 118 (21.1%) | ||
24:00 and after | 100 (31.8%) | 54 (9.7%) | ||
Timing of morning waking | Before 6:00 | 159 (50.6%) | 331 (59.2%) | 0.001 |
6:00 to 7:00 | 125 (39.8%) | 207 (37.0%) | ||
After 7:00 | 30 (9.6%) | 21 (3.8%) | ||
Sleep duration | < 6 h | 78 (24.8%) | 62 (11.1%) | < 0.001 |
6-9 h | 220 (70.1%) | 476 (85.1%) | ||
> 9 h | 16 (5.1%) | 21 (3.8%) | ||
Sleep quality | Very poor | 17 (5.4%) | 25 (4.5%) | 0.105 |
Fairly poor | 38 (12.1%) | 99 (17.7%) | ||
Fairly good | 126 (40.1%) | 230 (41.1%) | ||
Very good | 133 (42.4%) | 205 (36.7%) | ||
Insomnia frequency | Never | 125 (39.8%) | 168 (30.1%) | 0.037 |
≤ 3 times/month | 116 (36.9%) | 256 (45.8%) | ||
4–6 times/month | 44 (14.0%) | 76 (13.6%) | ||
7–12 times/month | 12 (3.8%) | 29 (5.2%) | ||
> 12 times/month | 17 (5.5%) | 30 (5.3%) | ||
Sleep medication use | Yes | 12 (3.8%) | 43 (7.7%) | 0.029 |
LAN | Level 1a | 9 (2.9%) | 9 (1.6%) | < 0.001 |
Level 2b | 28 (8.9%) | 37 (6.6%) | ||
Level 3c | 68 (21.7%) | 230 (41.2%) | ||
Level 4d | 209 (66.5%) | 283 (50.6%) | ||
Frequency of night-time waking | Never | 112 (35.7%) | 138 (24.7%) | 0.001 |
1 time | 89 (28.3%) | 175 (31.3%) | ||
2 times | 66 (21.0%) | 159 (28.4%) | ||
3 times | 29 (9.3%) | 37 (6.6%) | ||
> 3 times | 18 (5.7%) | 50 (9.0%) | ||
Night work | Yes | 37 (11.8%) | 32 (5.7%) | 0.002 |
Daytime napping | Yes | 110 (35.0%) | 234 (41.9%) | 0.051 |
Sleep noise | Never | 292 (93.0%) | 530 (94.8%) | 0.337 |
≤ 3 times/month | 4 (1.3%) | 9 (1.6%) | ||
4–12 times/month | 3 (1.0%) | 6 (1.1%) | ||
> 12 times/month | 15 (4.7%) | 14 (2.5%) |
Associations between sleep factors and AMI
Variables | Crude OR (95% CI) | P value | Adjusted OR (95% CI)e | P value | Adjusted OR (95% CI)f | P value | |
---|---|---|---|---|---|---|---|
Timing of sleep | Before 22:00 | 1 | 1 | 1 | |||
22:00 to 23:00 | 0.946 (0.650, 1.376) | 0.771 | 0.935 (0.625, 1.400) | 0.745 | 0.937 (0.624, 1.407) | 0.755 | |
23:00 to 24:00 | 1.190 (0.797, 1.776) | 0.395 | 1.124 (0.719, 1.757) | 0.607 | 1.149 (0.732, 1.803) | 0.546 | |
24:00 and after | 4.482 (2.963, 6.780) | < 0.001 | 3.866 (2.352, 6.354) | < 0.001 | 4.005 (2.418, 6.634) | < 0.001 | |
Timing of morning waking | Before 6:00 | 1 | 1 | 1 | |||
6:00 to 7:00 | 1.257 (0.939, 1.683) | 0.124 | 1.076 (0.773, 1.499) | 0.765 | 1.194 (0.826, 1.725) | 0.347 | |
After 7:00 | 2.974 (1.650, 5.359) | < 0.001 | 1.960 (1.020, 3.767) | 0.043 | 2.544 (1.239, 5.225) | 0.011 | |
Sleep duration | 6-9 h | 1 | 1 | 1 | |||
< 6 h | 2.722 (1.881, 3.940) | < 0.001 | 2.629 (1.770, 3.905) | < 0.001 | 2.968 (1.951, 4.516) | < 0.001 | |
> 9 h | 1.648 (0.844, 3.221) | 0.144 | 1.857 (0.913, 3.777) | 0.088 | 1.696 (0.795, 3.616) | 0.172 | |
Sleep quality | Very poor | 1 | 1 | 1 | |||
Fairly poor | 0.564 (0.275, 1.161) | 0.120 | 0.599 (0.277, 1.295) | 0.193 | 0.631 (0.288, 1.381) | 0.249 | |
Fairly good | 0.806 (0.419, 1.548) | 0.517 | 0.805 (0.399, 1.626) | 0.546 | 0.888 (0.434, 1.818) | 0.745 | |
Very good | 0.954 (0.496, 1.834) | 0.888 | 0.905 (0.447, 1.830) | 0.781 | 1.018 (0.495, 2.093) | 0.962 | |
Insomnia frequency | > 12 times/month | 1 | 1 | 1 | |||
Never | 1.313 (0.693, 2.486) | 0.403 | 1.103 (0.557, 2.186) | 0.779 | 1.361 (0.676, 2.742) | 0.388 | |
≤ 3 times/month | 0.800 (0.424, 1.508) | 0.490 | 0.738 (0.376, 1.449) | 0.377 | 0.908 (0.455, 1.811) | 0.784 | |
4–6 times/month | 1.022 (0.507, 2.060) | 0.952 | 1.082 (0.515, 2.274) | 0.836 | 1.212 (0.568, 2.589) | 0.619 | |
7–12 times/month | 0.730 (0.297, 1.793) | 0.493 | 1.059 (0.409, 2.740) | 0.906 | 1.224 (0.461, 3.252) | 0.684 | |
Sleep medication use | No | 1 | 1 | 1 | |||
Yes | 0.477 (0.248, 0.918) | 0.027 | 0.577 (0.289, 1.152) | 0.119 | 0.441 (0.212, 0.918) | 0.029 | |
LAN | Level 1a | 1 | 1 | 1 | |||
Level 2b | 0.757 (0.266, 2.154) | 0.602 | 0.661 (0.220, 1.990) | 0.462 | 0.466 (0.147, 1.477) | 0.194 | |
Level 3c | 0.296 (0.113, 0.774) | 0.013 | 0.282 (0.102, 0.778) | 0.015 | 0.243 (0.084, 0.700) | 0.009 | |
Level 4d | 0.739 (0.288, 1.893) | 0.528 | 0.695 (0.257, 1.875) | 0.472 | 0.598 (0.212, 1.684) | 0.330 | |
Frequency of night-time waking | Never | 1 | 1 | 1 | |||
1 time | 0.627 (0.439, 0.895) | 0.010 | 0.825 (0.559, 1.220) | 0.335 | 0.878 (0.589, 1.309) | 0.525 | |
2 times | 0.511 (0.350, 0.748) | 0.001 | 0.751 (0.488, 1.156) | 0.194 | 0.766 (0.494, 1.189) | 0.235 | |
3 times | 0.966 (0.559, 1.668) | 0.900 | 1.745 (0.940, 3.240) | 0.078 | 1.851 (0.984, 3.484) | 0.056 | |
> 3 times | 0.444 (0.245, 0.803) | 0.007 | 0.687 (0.357, 1.319) | 0.259 | 0.566 (0.288, 1.113) | 0.099 | |
Night work | No | 1 | 1 | 1 | |||
Yes | 2.200 (1.341, 3.609) | 0.002 | 1.407 (0.819, 2.417) | 0.216 | 0.648 (0.299, 1.404) | 0.272 | |
Daytime napping | No | 1 | 1 | 1 | |||
Yes | 0.749 (0.562, 0.997) | 0.048 | 0.765 (0.564, 1.037) | 0.084 | 0.765 (0.554, 1.056) | 0.104 | |
Sleep noise | Never | 1 | 1 | 1 | |||
≤ 3 times/month | 0.807 (0.246, 2.642) | 0.723 | 0.628 (0.176, 2.248) | 0.475 | 0.715 (0.190, 2.683) | 0.619 | |
4–12 times/month | 0.908 (0.225, 3.655) | 0.891 | 0.792 (0.185, 3.385) | 0.753 | 0.914 (0.204, 4.104) | 0.906 | |
> 12 times/month | 1.945 (0.926, 4.085) | 0.079 | 1.836 (0.833, 4.044) | 0.132 | 1.926 (0.813, 4.563) | 0.136 |
Subgroup analysis of the associations between sleep factors and AMI
Variables | ≤ 65 years (n = 554) | > 65 years (n = 319) | |||
---|---|---|---|---|---|
Adjusted OR (95% CI)e | P value | Adjusted OR (95% CI)e | P value | ||
Timing of sleep | Before 22:00 | 1 | 1 | ||
22:00 to 23:00 | 0.814 (0.466,1.422) | 0.469 | 0.884 (0.440,1.775) | 0.729 | |
23:00 to 24:00 | 0.800 (0.437,1.465) | 0.469 | 1.970 (0.897,4.324) | 0.091 | |
24:00 and after | 3.328 (1.773,6.245) | < 0.001 | 16.827 (4.492,63.026) | < 0.001 | |
Timing of morning waking | Before 6:00 | 1 | 1 | ||
6:00 to 7:00 | 1.136 (0.728,1.772) | 0.574 | 1.114 (0.568,2.184) | 0.754 | |
After 7:00 | 3.006 (1.357,6.663) | 0.007 | 1.460 (0.224,9.493) | 0.692 | |
Sleep duration | 6-9 h | 1 | 1 | ||
< 6 h | 2.522 (1.506,4.225) | < 0.001 | 5.121 (2.222,11.807) | < 0.001 | |
> 9 h | 1.607 (0.417,6.189) | 0.490 | 2.449 (0.912,6.574) | 0.076 | |
Sleep quality | Very poor | 1 | 1 | ||
Fairly poor | 0.841 (0.290,2.441) | 0.750 | 0.657 (0.165,2.614) | 0.551 | |
Fairly good | 2.067 (0.789,5.411) | 0.139 | 0.447 (0.122,1.638) | 0.224 | |
Very good | 1.939 (0.738,5.091) | 0.179 | 0.645 (0.175,2.381) | 0.510 | |
Insomnia frequency | > 12 times/month | 1 | 1 | ||
Never | 2.875 (1.001,8.260) | 0.050 | 0.915 (0.299,2.801) | 0.877 | |
≤ 3 times/month | 2.107 (0.737,6.019) | 0.164 | 0.419 (0.140,1.255) | 0.120 | |
4–6 times/month | 1.577 (0.515,4.829) | 0.425 | 1.493 (0.447,4.990) | 0.515 | |
7–12 times/month | 1.642 (0.343,7.867) | 0.535 | 0.908 (0.220,3.744) | 0.894 | |
Sleep medication use | No | 1 | 1 | ||
Yes | 0.361 (0.132,0.988) | 0.047 | 0.480 (0.136,1.695) | 0.254 | |
LAN | Level 1a | 1 | 1 | ||
Level 2b | 0.408 (0.096,1.744) | 0.227 | 0.257 (0.016,4.162) | 0.339 | |
Level 3c | 0.272 (0.070,1.049) | 0.059 | 0.061 (0.004,0.860) | 0.038 | |
Level 4d | 0.536 (0.144,2.004) | 0.354 | 0.324 (0.025,4.269) | 0.391 | |
Frequency of night-time waking | Never | 1 | 1 | ||
1 time | 0.814 (0.511,1.296) | 0.385 | 1.465 (0.572,3.749) | 0.426 | |
2 times | 0.521 (0.299,0.906) | 0.021 | 1.580 (0.636,3.928) | 0.325 | |
3 times | 2.097 (0.855,5.139) | 0.106 | 3.467 (1.091,11.019) | 0.035 | |
> 3 times | 0.724 (0.273,1.919) | 0.516 | 0.537 (0.156,1.857) | 0.326 | |
Night work | No | 1 | 1 | ||
Yes | 1.057 (0.589,1.894) | 0.853 | – | 0.999 | |
Daytime napping | No | 1 | 1 | ||
Yes | 0.645 (0.419,0.992) | 0.046 | 1.041 (0.561,1.930) | 0.899 | |
Sleep noise | Never | 1 | 1 | ||
≤ 3 times/month | 0.633 (0.160,2.511) | 0.515 | 0.960 (0.043,21.574) | 0.980 | |
4–12 times/month | 0.645 (0.106,3.913) | 0.633 | 1.468 (0.253,8.521) | 0.668 | |
> 12 times/month | 2.146 (0.737,6.250) | 0.161 | – | – |
Associations between sleep factors and Gensini score
Variables | High score group (> 42.0) (n = 352) | Low score group (≤ 42.0) (n = 357) | P value |
---|---|---|---|
Age (years) | 63 (53, 69) | 62 (54, 69) | 0.786 |
Men (n, %) | 276 (78.4%) | 250 (70.0%) | 0.013 |
BMI (kg/m2) | 24.8 (22.8, 27.3) | 24.7 (22.8, 26.9) | 0.503 |
Residence in cities (n, %) | 268 (76.1%) | 248 (69.5%) | 0.052 |
Education level (n, %) | |||
Illiterate | 47 (13.4%) | 69 (19.3%) | 0.012 |
Elementary school | 68 (19.3%) | 90 (25.2%) | |
Junior high school | 112 (31.8%) | 89 (24.9%) | |
Senior high school and technical secondary school | 67 (19.0%) | 68 (19.0%) | |
Junior college or above | 58 (16.5%) | 41 (11.5%) | |
Diabetes (n, %) | 84 (23.9%) | 69 (19.3%) | 0.145 |
Hypertension (n, %) | 209 (59.4%) | 217 (60.8%) | 0.759 |
Dyslipidemia (n, %) | 21 (6.0%) | 21 (5.9%) | 1.000 |
Family history of CAD (n, %) | 16 (4.5%) | 13 (3.6%) | 0.574 |
Statins (n, %) | 19 (5.4%) | 17 (4.8%) | 0.735 |
Antiplatelet agents (n, %) | 29 (8.2%) | 30 (8.4%) | 1.000 |
β-blockers (n, %) | 15 (4.3%) | 31 (8.7%) | 0.021 |
ACEI or ARB (n, %) | 75 (21.3%) | 102 (28.6%) | 0.030 |
Smoking (n, %) | |||
Never | 121 (34.4%) | 154 (43.1%) | 0.044 |
Former | 46 (13.1%) | 53 (14.8%) | |
< 20 cigarettes/day | 53 (15.1%) | 44 (12.3%) | |
≥ 20 cigarettes/day | 132 (37.5%) | 106 (29.7%) | |
Drinking (n, %) | |||
No | 189 (53.7%) | 199 (55.7%) | 0.048 |
1 to 3 times a month | 77 (21.9%) | 54 (15.1%) | |
1 to 6 times a week | 45 (12.8%) | 44 (12.3%) | |
At least once a day | 41 (11.6%) | 60 (16.8%) | |
Diet (n, %) | |||
Low-fat diet | 20 (5.7%) | 16 (4.5%) | 0.040 |
Normal diet | 196 (55.7%) | 232 (65.0%) | |
High-fat diet | 136 (38.6%) | 109 (30.5%) | |
Regular exercise (n, %) | 102 (29.0%) | 126 (35.3%) | 0.077 |
Variables | Crude OR (95% CI) | P value | Adjusted OR (95% CI)e | P value | Adjusted OR (95% CI)f | P value | |
---|---|---|---|---|---|---|---|
Timing of sleep | Before 22:00 | 1 | 1 | 1 | |||
22:00 to 23:00 | 1.076 (0.733, 1.580) | 0.708 | 1.036 (0.682, 1.573) | 0.868 | 1.075 (0.705,1.641) | 0.737 | |
23:00 to 24:00 | 1.140 (0.757, 1.717) | 0.531 | 1.132 (0.714, 1.795) | 0.599 | 1.153 (0.724,1.835) | 0.549 | |
24:00 and after | 1.815 (1.183, 2.784) | 0.006 | 1.671 (0.991, 2.821) | 0.054 | 1.683 (0.989,2.866) | 0.055 | |
Timing of morning waking | Before 6:00 | 1 | 1 | 1 | |||
6:00 to 7:00 | 1.248 (0.914, 1.705) | 0.163 | 1.179 (0.828, 1.680) | 0.361 | 1.324 (0.903,1.940) | 0.151 | |
After 7:00 | 1.335 (0.724, 2.464) | 0.355 | 0.987 (0.499, 1.952) | 0.969 | 1.250 (0.593,2.634) | 0.557 | |
Sleep duration | 6-9 h | 1 | 1 | 1 | |||
< 6 h | 2.070 (1.380, 3.106) | < 0.001 | 2.221 (1.447, 3.409) | < 0.001 | 2.374 (1.523,3.703) | < 0.001 | |
> 9 h | 1.502 (0.732, 3.079) | 0.267 | 1.442 (0.674, 3.085) | 0.346 | 1.234 (0.554,2.750) | 0.606 | |
Sleep quality | Very poor | 1 | 1 | 1 | |||
Fairly poor | 0.355 (0.159, 0.795) | 0.012 | 0.386 (0.166, 0.898) | 0.027 | 0.435 (0.183,1.034) | 0.060 | |
Fairly good | 0.565 (0.269, 1.184) | 0.130 | 0.583 (0.269, 1.264) | 0.171 | 0.691 (0.310,1.539) | 0.365 | |
Very good | 0.553 (0.264, 1.161) | 0.117 | 0.577 (0.265, 1.254) | 0.165 | 0.680 (0.304,1.521) | 0.348 | |
Insomnia frequency | > 12 times/month | 1 | 1 | 1 | |||
Never | 0.892 (0.462, 1.725) | 0.735 | 0.830 (0.410, 1.681) | 0.605 | 0.835 (0.411,1.698) | 0.619 | |
≤ 3 times/month | 0.611 (0.318, 1.174) | 0.139 | 0.574 (0.288, 1.145) | 0.115 | 0.574 (0.287,1.150) | 0.117 | |
4–6 times/month | 0.800 (0.384, 1.667) | 0.551 | 0.834 (0.387, 1.797) | 0.643 | 0.813 (0.376,1.758) | 0.598 | |
7–12 times/month | 0.469 (0.173, 1.273) | 0.137 | 0.616 (0.214, 1.776) | 0.370 | 0.598 (0.207,1.727) | 0.342 | |
Sleep medication use | No | 1 | 1 | 1 | |||
Yes | 0.503 (0.265, 0.956) | 0.036 | 0.586 (0.298, 1.153) | 0.122 | 0.512 (0.255,1.028) | 0.060 | |
LAN | Level 1a | 1 | 1 | 1 | |||
Level 2b | 1.037 (0.338, 3.180) | 0.949 | 1.193 (0.376, 3.785) | 0.765 | 1.006 (0.294,3.442) | 0.992 | |
Level 3c | 0.626 (0.225, 1.738) | 0.368 | 0.678 (0.237, 1.940) | 0.469 | 0.649 (0.211,1.992) | 0.449 | |
Level 4d | 0.817 (0.299, 2.236) | 0.694 | 0.900 (0.319, 2.537) | 0.842 | 0.825 (0.274,2.483) | 0.732 | |
Frequency of night-time waking | Never | 1 | 1 | 1 | |||
1 time | 0.965 (0.655, 1.420) | 0.856 | 1.042 (0.682, 1.591) | 0.851 | 1.069 (0.697,1.639) | 0.760 | |
2 times | 0.633 (0.424, 0.944) | 0.025 | 0.674 (0.426, 1.067) | 0.092 | 0.672 (0.423,1.068) | 0.092 | |
3 times | 0.599 (0.328, 1.092) | 0.095 | 0.725 (0.369, 1.421) | 0.349 | 0.739 (0.375,1.456) | 0.382 | |
> 3 times | 0.699 (0.388, 1.258) | 0.233 | 0.627 (0.323, 1.217) | 0.168 | 0.620 (0.318,1.211) | 0.162 | |
Night work | No | 1 | 1 | 1 | |||
Yes | 1.054 (0.618, 1.796) | 0.847 | 0.879 (0.492, 1.572) | 0.664 | 0.540 (0.250,1.166) | 0.117 | |
Daytime napping | No | 1 | 1 | 1 | |||
Yes | 0.810 (0.600, 1.094) | 0.170 | 0.829 (0.603, 1.139) | 0.247 | 0.810(0.583,1.126) | 0.211 | |
Sleep noise | Never | 1 | 1 | 1 | |||
≤ 3 times/month | 3.156 (0.633, 15.751) | 0.705 | 2.233 (0.431, 11.568) | 0.338 | 2.708(0.491,14.953) | 0.253 | |
4–12 times/month | 1.052 (0.261, 4.242) | 0.676 | 1.199 (0.286, 5.035) | 0.804 | 1.190 (0.273,5.184) | 0.816 | |
> 12 times/month | 2.104 (0.889, 4.983) | 0.091 | 2.540 (1.026, 6.287) | 0.044 | 2.422 (0.935,6.277) | 0.069 |