Table 1.
General characteristics and Insomnia Severity Index (ISI)/Epworth Sleepiness Scale (ESS) results by noise exposure groups
| Characteristics | All groups | Control | Low-exposure (75-80 WECPNL) | High-exposure (80-90 WECPNL) | p-value | |
|---|---|---|---|---|---|---|
| n = 3308(%) | n = 477(%) | n = 1403(%) | N = 1428(%) | |||
| Sexa) | Male | 1111(33.6) | 153(32.1) | 443(31.6) | 515(36.1) | 0.0308 |
| Female | 2197(66.4) | 324(67.9) | 960(68.4) | 913(63.9) | ||
| Mean age(years)b) | 50.5 ± 14.2 | 50.5 ± 14.4 | 50.6 ± 14.1 | 50.4 ± 14.2 | 0.9116 | |
| Age(years)a) | 20-29 | 268(8.1) | 44(9.2) | 110(7.8) | 114(8.0) | 0.4197 |
| 30-39 | 585(17.7) | 81(17.0) | 240(17.1) | 264(18.5) | ||
| 40-49 | 656(19.8) | 77(16.1) | 300(21.4) | 279(19.5) | ||
| 50-59 | 739(22.3) | 121(25.4) | 297(21.2) | 321(22.5) | ||
| 60-69 | 764(23.1) | 108(22.6) | 330(23.5) | 326(22.8) | ||
| 70-74 | 296(9.0) | 46(9.6) | 126(9.0) | 124(8.7) | ||
| Educationa) | Never | 77(2.3) | 4(0.8) | 26(1.8) | 47(3.3) | <0.0001 |
| Elementary school | 343(10.4) | 28(5.9) | 134(9.6) | 181(12.7) | ||
| Middle school | 512(15.5) | 57(11.9) | 242(17.3) | 213(14.9) | ||
| High school | 1407(42.5) | 225(47.2) | 552(39.3) | 630(44.1) | ||
| College or more | 969(29.3) | 163(34.2) | 449(32.0) | 357(25.0) | ||
| Residency period(year)a) | ≥15 | 826(28.7) | 86(20.3) | 382(31.4) | 358(29.0) | <0.0001 |
| 10-14 | 655(22.8) | 120(28.4) | 287(23.6) | 248(20.1) | ||
| 5-9 | 679(23.6) | 101(23.9) | 260(21.4) | 318(25.7) | ||
| <5 | 716(24.9) | 116(27.4) | 288(23.7) | 312(25.2) | ||
| Drinkinga) | No | 2055(62.1) | 284(59.5) | 906(64.6) | 865(60.6) | 0.0408 |
| Yes | 1253(37.9) | 193(40.5) | 497(35.4) | 563(39.4) | ||
| Smokinga) | Never | 2546(77.4) | 369(77.4) | 1102(78.5) | 1075(75.3) | 0.2182 |
| Past smoker | 273(8.2) | 43(9.0) | 101(7.2) | 129(9.0) | ||
| Current smoker | 489(14.8) | 65(13.6) | 200(14.3) | 224(15.7) | ||
| Regular Exercisea) | No | 1793(54.2) | 234(49.1) | 782(55.7) | 777(54.4) | 0.0398 |
| Yes | 1515(45.8) | 243(50.9) | 621(44.3) | 651(45.6) | ||
| Operation or hospitalization within 1 yeara) | No | 3025(91.4) | 446(93.5) | 1296(92.4) | 1283(89.9) | 0.0123 |
| Yes | 283(8.6) | 31(6.5) | 107(7.6) | 145(10.1) | ||
| ISIc) | Meanb) | 6.9 ± 6.4 | 4.1 ± 5.1 | 7.2 ± 6.5 | 7.6 ± 6.4 | <0.0001 |
| Normal | 1956(59.1) | 376(78.8) | 782(55.7) | 798(55.9) | <0.0001 | |
| Sub-threshold insomnia | 897(27.1) | 75(15.7) | 426(30.4) | 396(27.7) | ||
| Moderate insomnia | 382(11.6) | 25(5.2) | 155(11.1) | 202(14.2) | ||
| Severe insomnia | 73(2.2) | 1(0.2) | 40(2.8) | 32(2.2) | ||
| ESSc) | Meanb) | 5.5 ± 3.7 | 4.1 ± 3.0 | 5.4 ± 3.7 | 6.0 ± 3.8 | <0.0001 |
| Normal | 2853(86.2) | 451(94.5) | 1214(86.5) | 1188(83.2) | <0.0001 | |
| Daytime hypersomnia | 455(13.8) | 26(5.5) | 189(13.5) | 240(16.8) |
a)By Chi-square test
b)By ANOVA
c)By Mantel-Haenszel Chi-square test