Table 1.
Characteristics of 85 subjects with metastatic breast cancer.
| Variables | Total (N=85) |
Aligned bedtime (N=72) |
Misaligned bedtime (N=13) |
|
|---|---|---|---|---|
| Age at initial diagnosis | ||||
| All subjects [Mean (SD, range)] years | 46.1 (8.0, 28– 67) |
45.3 (7.3, 32–65) | 50.5 (10.3, 28–67) | t = −2.210, df = 83, p = 0.030 |
| 28–39 years | 18 (21.2) | 16 (22.2) | 2 (15.4) | p = 0.025g |
| 40–49 years | 42 (49.4) | 39 (54.2) | 3 (23.1) | |
| 50–67 years | 25 (29.4) | 17 (23.6) | 8 (61.5) | |
| Ethnicity | ||||
| Asian | 3 (3.5) | 3 (4.2) | 0 | p=0.166g |
| Black | 6 (7.1) | 3 (4.2) | 3 (23.1) | |
| Hispanic | 1 (1.2) | 1 (1.4) | 0 (0.0) | |
| White | 75 (88.2) | 65 (90.3) | 10 (76.9) | |
| Educational level | ||||
| High school | 7 (8.2) | 5 (6.9) | 2 (15.4) | p=0.450g |
| College - Bachelor’s degree | 43 (50.6) | 35 (48.6) | 8 (61.5) | |
| Graduate school – Master’s degree | 25 (29.4) | 23 (31.9) | 2 (15.4) | |
| Ph.D., M.D., J.D. | 10 (11.8) | 9 (12.5) | 1 (7.7) | |
| Marital status | ||||
| Married | 6 (7.1) | 4 (5.6) | 2 (15.4) | p=0.14g |
| Never married | 47 (55.3) | 44 (61.1) | 3 (23.1) | |
| Separated | 4 (4.7) | 3 (4.2) | 1 (7.7) | |
| Divorced | 22 (25.9) | 18 (25.0) | 4 (30.8) | |
| Widowed | 5 (5.9) | 2 (2.8) | 3 (23.1) | |
| Others | 1 (1.2) | 1 (1.4) | 0 (0.0) | |
| Total gross household income | ||||
| < $20,000 | 11 (13.3) | 7 (9.9) | 4 (33.3) | p=0.026g |
| $20,000 – $39,999 | 13 (15.7) | 13 (18.3) | 0 (0.0) | |
| $40,000 – $59,999 | 10 (12.0) | 7 (9.9) | 3 (25.0) | |
| $60,000 – $79,999 | 7 (8.4) | 7 (9.9) | 0 (0.0) | |
| $80,000 – $99,999 | 13 (15.7) | 10 (14.1) | 3 (25.0) | |
| $100,000 or above | 29 (34.9) | 27 (38.0) | 2 (16.7) | |
| Employment status | ||||
| Full time | 23 (27.1) | 20 (27.8) | 3 (23.1) | p=0.408g |
| Part time | 17 (20.0) | 16 (22.2) | 1 (7.7) | |
| None | 45 (52.9) | 36 (50.0) | 9 (69.2) | |
| Amount of caffeine consumption, mg | ||||
| Morning [Mean (SD)] | 163.2 (268.4) | 176.3 (279.1) | 90.7 (191.4) | p=0.027h |
| Afternoon [Mean (SD)] | 36.0 (75.4) | 31.0 (45.5) | 63.3 (163.3) | p=0.830h |
| Evening [Mean (SD)] | 11.9 (21.8) | 11.3 (22.0) | 14.8 (21.0) | p=0.560h |
| CES-D [Mean (SD)] | 8.9 (7.0) | 8.5 (6.4) | 11.2 (9.6) | P=0.423h |
| STAI, trait [Mean (SD)] | 34.1 (8.8) | 34.4 (8.6) | 32.5 (10.2) | p=0.343h |
| STAI, state [Mean (SD)] | 28.5 (7.6) | 28.6 (7.5) | 28.6 (8.5) | p=0.864h |
| PCL-C, total [Mean (SD)] | 28.6 (9.2) | 29.3 (9.4) | 24.8 (7.3) | p=0.060h |
| PCL-C, reexperience/intrusion [Mean (SD)] | 7.9 (3.5) | 8.1 (3.7) | 6.9 (1.8) | p=0.366h |
| PCL-C, avoidance/numbing [Mean (SD)] | 11.6 (4.2) | 12.0 (4.2) | 9.5 (4.0) | p=0.012h |
| PCL-C, arousal [Mean (SD)] | 9.1 (3.1) | 9.2 (3.2) | 8.5 (2.8) | p=0.514h |
| BPI, severity [Mean (SD)] | 2.0 (1.9) | 1.8 (1.7) | 3.2 (2.5) | p=0.052h |
| BPI, interference [Mean (SD)] | 1.7 (2.0) | 1.5 (1.7) | 2.9 (2.7) | p=0.086h |
| Stage at initial diagnosis | ||||
| 0 | 5 (5.9) | 4 (5.6) | 1 (7.7) | p=0.172g |
| I | 28 (32.9) | 24 (33.3) | 4 (30.8) | |
| II | 36 (42.4) | 33 (45.8) | 3 (23.1) | |
| III | 16 (18.8) | 11 (15.3) | 5 (38.5) | |
| Receptor status at initial diagnosis | ||||
| Estrogen receptor + | 70 (82.4) | 60 (83.3) | 10 (76.9) | p=0.692g |
| Progesterone receptor + a | 58 (71.6) | 51 (72.9) | 7 (63.6) | p=0.498g |
| HER2 receptor + b | 17 (22.7) | 17 (26.6) | 0 (0.0) | p=0.060g |
| Treatment before metastasis or recurrence | ||||
| Surgery + | 80 (94.1) | 68 (94.4) | 12 (92.3) | p=0.573g |
| Chemotherapy + | 54 (63.5) | 44 (61.1) | 10 (76.9) | p=0.358g |
| Radiation therapy + | 41 (48.2) | 36 (50.0) | 5 (38.5) | χ2=0.587, p=0.444 |
| Hormonal therapy + | 43 (50.6) | 37 (51.4) | 6 (46.2) | χ2=0.121, p=0.728 |
| Herceptin + | 2 (2.4) | 2 (2.8) | 0 (0.0) | p=1.000g |
| Natural killer cell count/mm3 [Mean (SD, range)]c |
136 (77, 24– 431) |
140 (77, 24–431) | 112 (73, 29–265) | p=0.353h |
| Higher natural killer cell counte | 36 (50.0) | 31 (50.0) | 5 (50.0) | χ2=0.000, p=1.000 |
| Karnofsky performance rating [Mean (SD)]d | 92.4 (10.2) | 92.3 (10.2) | 93.0 (10.6) | p=0.730h |
| Chronotype score [Mean (SD, range)] | 22.3 (4.4, 13– 32) |
22.6 (3.9, 14–32) | 20.7 (6.8, 13–32) | t=0.968, df=13.42, p=0.350 |
| Chronotypef | p=0.008g | |||
| Morning type | 43 (50.6) | 38 (52.8) | 5 (38.5) | |
| Neither type | 36 (42.4) | 32 (44.4) | 4 (30.8) | |
| Evening type | 6 (7.1) | 2 (2.8) | 4 (30.8) |
SD, standard deviation; CES-D, Center for Epidemiologic Studies-Depression; STAI, State and Trait Anxiety Index; PCL-C, Post-Traumatic Stress Disorder Checklist-Civilian version; BPI, Brief Pain Inventory; HER2, Human Epidermal Growth Factor Receptor 2.
a
: n=81,
b
: n=75,
c
: n=72,
d
n=71
e
NK-cell count was classified into higher and lower one by median value of 116.97/mm3
f
Chronotype was classified into three types according to MEQ score (morning type 32 – 23, neither type 22 – 16, evening type 15 – 6)
g
Fisher’s exact test
h
Mann-Whitney U-test
Data are shown as number of subjects (percentage of subjects) unless otherwise noted.