Table 1 Mean values of baseline characteristics according to current shift work and tertile of shift work duration
From: Association between shift work and obesity among female nurses: Korean Nurses’ Survey
Variables | Total | Current shift work | P-value | Tertile of shift work duration | P-value | |||
|---|---|---|---|---|---|---|---|---|
No | Yes | Tertile 1 | Tertile 2 | Tertile 3 | ||||
(n = 9,989) | (n = 4,702) | (n = 5,287) | (n = 1,732) | (n = 1,731) | (n = 1,686) | |||
Age (years) | 33.2 ± 8.6 | 37.6 ± 9.2 | 29.2 ± 5.6 | <0.001 | 24.9 ± 2.9c | 28.1 ± 3.1b | 34.7 ± 5.1a | <0.001 |
BMI (kg/m2) | 20.9 ± 2.5 | 21.4 ± 2.6 | 20.5 ± 2.5 | <0.001 | 20.0 ± 2.1c | 20.2 ± 2.4b | 21.3 ± 2.7a | <0.001 |
Hypertension | 220 (2.2) | 193 (4.1) | 27 (0.5) | <0.001 | 3 (0.2) | 6 (0.3) | 16 (0.9) | 0.003 |
Diabetes | 43 (0.4) | 31 (0.7) | 12 (0.2) | 0.001 | 3 (0.2) | 4 (0.2) | 5 (0.3) | <0.001 |
Osteoporosis | 102 (1.0) | 79 (1.7) | 23 (0.4) | <0.001 | 1 (0.1) | 6 (0.3) | 13 (0.8) | 0.003 |
Hyperlipidemia | 57 (7.6) | 472 (10.0) | 285 (5.4) | <0.001 | 40 (2.3) | 78 (4.5) | 165 (9.8) | <0.001 |
Breast cancer | 87 (0.9) | 73 (1.6) | 14 (0.3) | <0.001 | 1 (0.1) | 3 (0.2) | 10 (0.6) | 0.007 |
Current smoking status | 0.335 | <0.001 | ||||||
No | 9874 (98.8) | 4653 (99.0) | 5221 (98.8) | 1697 (98.0) | 1718 (99.2) | 1675 (99.3) | ||
Yes | 115 (1.2) | 49 (1.0) | 66 (1.2) | 35 (2.0) | 13 (0.8) | 11 (0.7) | ||
Regular drinking habit | <0.001 | <0.001 | ||||||
No | 5144 (51.5) | 2683 (57.1) | 2461 (46.5) | 625 (36.1) | 788 (45.5) | 993 (58.9) | ||
Yes | 4845 (48.5) | 2019 (42.9) | 2826 (53.5) | 1107 (63.9) | 943 (54.5) | 693 (41.1) | ||
Marital status | <0.001 | <0.001 | ||||||
Married (remarriage) | 4589 (45.9) | 3087 (65.7) | 1502 (28.4) | 88 (5.1) | 344 (19.9) | 1032 (61.2) | ||
Cohabitation | 16 (0.2) | 6 (0.1) | 10 (0.2) | 3 (0.2) | 2 (0.1) | 4 (0.2) | ||
Divorced | 246 (2.5) | 127 (2.7) | 119 (2.3) | 31 (1.8) | 42 (2.5) | 40 (2.4) | ||
Widowed | 36 (0.4) | 34 (0.7) | 2 (0.0) | 0 (0.0) | 0 (0.0) | 2 (0.1) | ||
Never-married | 5102 (51.1) | 1448 (30.8) | 3654 (69.1) | 1610 (93.0) | 1341 (77.5) | 608 (36.1) | ||
Family income | <0.001 | <0.001 | ||||||
Less than 30 million won | 1259 (12.6) | 490 (10.4) | 769 (14.5) | 401 (23.2) | 247 (14.3) | 96 (5.7) | ||
30-45 million won | 2787 (27.9) | 1002 (21.3) | 1785 (33.8) | 605 (34.9) | 685 (39.6) | 454 (26.9) | ||
45-75 million won | 3545 (35.5) | 1802 (38.3) | 1743 (33.0) | 472 (27.3) | 522 (30.2) | 699 (41.5) | ||
More than 75 million won | 2389 (24.0) | 1408 (29.9) | 990 (18.7) | 254 (14.7) | 277 (16.0) | 437 (25.9) | ||
Education | <0.001 | <0.001 | ||||||
Graduation from three-year course | 3469 (34.7) | 1294 (27.5) | 2175 (41.1) | 845 (48.8) | 733 (42.3) | 528 (31.3) | ||
Graduation from four-year course | 4839 (48.4) | 2083 (44.3) | 2756 (52.1) | 880 (50.8) | 954 (55.1) | 862 (51.1) | ||
Graduate school or higher | 1681 (16.8) | 1325 (28.2) | 356 (6.7) | 7 (0.4) | 44 (2.5) | 296 (17.6) | ||
Dietary habits | ||||||||
Breakfast skipping | 3649 (36.5) | 1371 (29.2) | 2278 (43.1) | <0.001 | 749 (43.2) | 815 (47.1) | 647 (38.4) | <0.001 |
Lunch skipping | 129 (1.3) | 23 (0.5) | 106 (2.0) | <0.001 | 50 (2.9) | 35 (2.0) | 19 (1.1) | <0.001 |
Dinner skipping | 96 (1.0) | 38 (0.8) | 58 (1.1) | 0.140 | 20 (1.2) | 23 (1.3) | 14 (0.8) | <0.001 |
Regular exercise | <0.001 | <0.001 | ||||||
No | 5588 (55.9) | 2478 (52.7) | 3110 (58.8) | 1063 (61.4) | 957 (55.3) | 1010 (59.9) | ||
Yes | 4401 (44.1) | 2224 (47.3) | 2177 (41.2) | 669 (38.6) | 774 (44.7) | 676 (40.1) | ||
Sleep problems, during the last 2 weeks | <0.001 | <0.001 | ||||||
Never | 4540 (45.4) | 2815 (59.9) | 1725 (32.6) | 477 (27.5) | 494 (28.5) | 707 (41.9) | ||
1-6 days | 3538 (35.4) | 1414 (30.1) | 2124 (40.2) | 685 (39.5) | 702 (40.6) | 679 (40.3) | ||
7-13 days | 1187 (11.9) | 304 (6.5) | 883 (16.7) | 333 (19.2) | 331 (19.1) | 202 (12.0) | ||
Every day | 724 (7.2) | 169 (3.6) | 555 (10.5) | 237 (13.7) | 204 (11.8) | 98 (5.8) | ||
Self-perceived health status | <0.001 | 0.003 | ||||||
Very good | 716 (7.2) | 389 (8.3) | 327 (6.2) | 119 (6.9) | 105 (6.1) | 92 (5.5) | ||
Good | 4545 (45.5) | 2219 (47.2) | 2326 (44.0) | 804 (46.4) | 756 (43.7) | 710 (42.1) | ||
Fair | 3837 (38.4) | 1735 (36.9) | 2102 (39.8) | 662 (38.2) | 666 (38.5) | 716 (42.5) | ||
So-so | 753 (7.5) | 290 (6.2) | 463 (8.8) | 134 (7.7) | 174 (10.1) | 143 (8.5) | ||
Bad | 138 (1.4) | 69 (1.5) | 69 (1.3) | 13 (0.8) | 30 (1.7) | 25 (1.5) | ||