Table 1.
Baseline characteristics of participants by total sedentary time, Women's Health Initiative Observational Study and Extension Study (WHI-OSES), (N = 61,609).
| Characteristic | Total sedentary time (hours per day)1 | P value2 | |||
|---|---|---|---|---|---|
| Q1 (≤6 hrs/day) | Q2 (>6–8 hrs/day) | Q3 (>8–11 hrs/day) | Q4 (>11 hrs/day) | ||
| n (%) | n (%) | n (%) | n (%) | ||
| All | 19364 (31.53%) | 12316 (20.06%) | 15958 (25.99%) | 13769 (22.42%) | |
|
| |||||
| Age group at screening, years | <.0001 | ||||
| 50–59 | 6010 (31.04%) | 3622 (29.41%) | 5622 (35.23%) | 6049 (43.93%) | |
| 60–69 | 9213 (47.58%) | 5927 (48.12%) | 7097 (44.47%) | 5623 (40.84%) | |
| 70–79 | 4141 (21.39%) | 2767 (22.47%) | 3239 (20.30%) | 2097 (15.23%) | |
|
| |||||
| Ethnicity | <.0001 | ||||
| White | 16507 (85.25%) | 11103 (90.15%) | 14355 (89.95%) | 12301 (89.34%) | |
| Black | 1387 (7.16%) | 564 (4.58%) | 743 (4.66%) | 744 (5.40%) | |
| Hispanic | 694 (3.58%) | 264 (2.14%) | 300 (1.88%) | 248 (1.80%) | |
| American Indian | 84 (0.43%) | 36 (0.29%) | 50 (0.31%) | 34 (0.25%) | |
| Asian/Pacific Islander | 410 (2.12%) | 213 (1.73%) | 326 (2.04%) | 300 (2.18%) | |
| Unknown | 282 (1.46%) | 136 (1.10%) | 184 (1.15%) | 142 (1.03%) | |
|
| |||||
| Income | <.0001 | ||||
| <$20,000 | 2513 (13.94%) | 1327 (11.51%) | 1671 (11.05%) | 1387 (10.59%) | |
| $20,000–$34,999 | 3920 (21.74%) | 2604 (22.59%) | 3255 (21.52%) | 2775 (21.19%) | |
| $35,000–$49,999 | 3724 (20.66%) | 2408 (20.89%) | 3100 (20.50%) | 2670 (20.38%) | |
| $50,000–$74,999 | 3809 (21.13%) | 2515 (21.82%) | 3447 (22.79%) | 2962 (22.61%) | |
| ≥$75,000 | 4062 (22.53%) | 2674 (23.20%) | 3651 (24.14%) | 3304 (25.23%) | |
|
| |||||
| Education | <.0001 | ||||
| None-HS diploma | 4040 (21.01%) | 2217(18.11%) | 2507 (15.84%) | 2066 (15.12%) | |
| School after HS | 7050 (36.67%) | 4335(35.41%) | 5557 (35.10%) | 4685 (34.28%) | |
| College degree or higher | 8135 (42.31%) | 5689(46.47%) | 7768 (49.07%) | 6917 (50.61%) | |
|
| |||||
| Physical activity | <.0001 | ||||
| Inactive (no reported recreational activity) | 1971 (10.26%) | 1250 (10.24%) | 1815 (11.46%) | 2243 (16.42%) | |
| <5 MET-hrs/week | 3026 (15.75%) | 2066 (16.92%) | 2851 (18.01%) | 2871 (21.02%) | |
| 5-<12 MET-hrs/week | 4251 (22.12%) | 2830 (23.18%) | 3942 (24.90%) | 3382 (24.76%) | |
| ≥12 MET-hrs/week | 9967 (51.87%) | 6064 (49.66%) | 7223 (45.63%) | 5162 (37.79%) | |
|
| |||||
| Self-rate health status | <.0001 | ||||
| Excellent | 4366 (22.62%) | 2545 (20.72%) | 3312 (20.79%) | 2587 (18.83%) | |
| Very good | 8399 (43.51%) | 5552 (45.21%) | 6984 (43.84%) | 5764 (41.96%) | |
| Good | 5324 (27.58%) | 3525 (28.71%) | 4624 (29.03%) | 4188 (30.48%) | |
| Fair/poor | 1214 (6.29%) | 658 (5.36%) | 1009 (6.33%) | 1199 (8.73%) | |
|
| |||||
| BMI | <.0001 | ||||
| <18.5 | 260 (1.36%) | 135 (1.11%) | 157 (0.99%) | 112 (0.82%) | |
| 18.5–24.9 | 8655 (45.20%) | 5389 (44.27%) | 6450 (40.87%) | 5007 (36.83%) | |
| 25–29.9 | 6646 (34.70%) | 4112 (33.78%) | 5520 (34.98%) | 4464 (32.83%) | |
| >30.0 | 3589 (18.74%) | 2536 (20.83%) | 3655 (23.16%) | 4013 (29.52%) | |
|
| |||||
| Smoking | <.0001 | ||||
| Never | 10296 (53.85%) | 6323 (51.92%) | 7874 (49.84%) | 6425 (47.14%) | |
| Past | 7873 (41.18%) | 5258 (43.17%) | 7127 (45.12%) | 6380 (46.81%) | |
| Current | 951 (4.97%) | 598 (4.91%) | 796 (5.04%) | 825 (6.05%) %) | |
|
| |||||
| Alcohol intake, per week | <.0001 | ||||
| 0/past drinker | 5456 (28.34%) | 3078 (25.08%) | 3793 (23.86%) | 3381 (24.66%) | |
| <1 | 5966 (30.99%) | 3851 (31.38%) | 5180 (32.59%) | 4732 (34.51%) | |
| 1–14 | 6961 (36.16%) | 4769 (38.85%) | 6134 (38.59%) | 4939 (36.02%) | |
| ≥14 | 866 (4.50%) | 576 (4.69%) | 789 (4.96%) | 661 (4.82%) | |
|
| |||||
| Hormone use | <.0001 | ||||
| Never used | 5485 (28.83%) | 3452 (28.55%) | 4304 (27.46%) | 3526 (26.10%) | |
| Past user | 3811 (20.03%) | 2382 (19.70%) | 3127 (19.95%) | 2656 (19.66%) | |
| Current user | 9729 (51.14%) | 6257 (51.75%) | 8245 (52.60%) | 7326 (54.23%) | |
|
| |||||
| Depressed mood | <.0001 | ||||
| 0 | 5906 (31.00%) | 3442 (28.26%) | 4068 (25.70%) | 3047 (22.36%) | |
| 1-2 | 7137 (37.46%) | 4840 (39.74%) | 6183 (39.06%) | 5191 (38.09%) | |
| 3-4 | 3670 (19.26%) | 2355 (19.33%) | 3297 (20.83%) | 2955 (21.68%) | |
| 5+ | 2340 (12.28%) | 1543 (12.67%) | 2282 (14.42%) | 2437 (17.88%) | |
|
| |||||
| Living alone | 4025 (20.90%) | 2815 (22.96%) | 4028 (25.34%) | 3963 (28.92%) | <.0001 |
|
| |||||
| Activity of daily living disability (≥1 disability) | 238 (1.27%) | 139 (1.16%) | 200 (1.29%) | 281 (2.10%) | <.0001 |
|
| |||||
| History of CHD3 | 1098 (5.77%) | 759 (6.24%) | 958 (6.09%) | 789 (5.82%) | 0.2638 |
|
| |||||
| History of CHF | 159 (0.84%) | 99 (0.82%) | 156 (1.00%) | 126 (0.93%) | 0.3204 |
|
| |||||
| History of stroke | 217 (1.12%) | 126 (1.02%) | 159 (1.00%) | 144 (1.05%) | 0.6934 |
|
| |||||
| History of diabetes (use of pills or shots) | 500 (2.59%) | 295 (2.40%) | 439 (2.75%) | 442 (3.21%) | 0.0003 |
|
| |||||
| Hypertensive (on medications for high blood pressure) | 6826 (35.64%) | 4340 (35.61%) | 5594 (35.39%) | 4715 (34.61%) | 0.2261 |
|
| |||||
| History of arthritis | 8672 (45.11%) | 5852 (47.78%) | 7590 (47.85%) | 6577 (47.99%) | <.0001 |
|
| |||||
| History of cancer | 2255 (11.73%) | 1513 (12.36%) | 1954 (12.32%) | 1728 (12.61%) | 0.0826 |
|
| |||||
| History of COPD3 | 533 (2.81%) | 349 (2.89%) | 507 (3.23%) | 518 (3.83%) | <.0001 |
|
| |||||
| Number of falls in the previous 12 months | <.0001 | ||||
| None | 13245 (69.14%) | 8353 (68.47%) | 10530 (66.64%) | 8924 (65.44%) | |
| 1 time | 3741 (19.53%) | 2436 (19.97%) | 3254 (20.59%) | 2867 (21.03%) | |
| 2 times | 1467 (7.66%) | 928 (7.61%) | 1372 (8.68%) | 1212 (8.89%) | |
| 3 or more times | 703 (3.67%) | 482 (3.95%) | 646 (4.09%) | 633 (4.64%) | |
|
| |||||
| History of hip fracture at age ≥55 years | 83 (0.54%) | 70 (0.72%) | 77 (0.63%) | 67 (0.68%) | 0.3034 |
|
| |||||
| Number of chronic diseases | <.0001 | ||||
| 0 | 4515 (23.32%) | 2699 (21.91%) | 3406 (21.34%) | 2934 (21.31%) | |
| 1 | 6441 (33.26%) | 4041 (32.81%) | 5181 (32.47%) | 4357 (31.64%) | |
| 2 | 4661 (24.07%) | 3065 (24.89%) | 3955 (24.78%) | 3391 (24.63%) | |
| 3 | 2336 (12.06%) | 1532 (12.44%) | 2074 (13.00%) | 1819 (13.21%) | |
| 4 | 932 (4.81%) | 656 (5.33%) | 876 (5.49%) | 850 (6.17%) | |
| 5+ | 479 (2.47%) | 323 (2.62%) | 466 (2.92%) | 418 (3.04%) | |
1All WHI-OS participants who reported on sitting time and sleeping time at baseline were enrolled in the extension study and had filled out at least one Form 151 (N = 61,609). All the percentage calculations were based on number of participants who reported on the individual variable.
2 P value was based on chi-square test for the null hypothesis of no overall difference in the baseline variable among the 4 groups.
3Coronary heart disease (CHD) included MI, angina, CABG, and PTCA.