Background
Methods
Design
Samples
Breast cancer group
Control group
Measurements
Data collection
Statistical analyses
Results
Descriptive data
Demographic & clinical variables
|
Breast cancer group n (%)
|
Control group n (%)
|
df
|
p value
|
---|---|---|---|---|
Age in years, Mean (SD)
| 46.1 (9.8) | 46.6 (8.4) | 370 | .071a
|
Marital status
| 2 | .572b
| ||
Single | 11 (6.8) | 24 (11.4) | ||
Married | 129 (79.6) | 170 (81.0) | ||
Divorced/Widowed | 22 (13.6) | 16 (7.6) | ||
Education
| 1 | .557b
| ||
Primary school | 23 (14.2) | 35 (16.7) | ||
Secondary school | 27 (16.7) | 23 (11.0) | ||
High school | 4 (2.5) | 6 (2.9) | ||
Diploma | 57 (35.2) | 75 (35.7) | ||
University | 51 (31.5) | 71 (33.8) | ||
Working status
| 2 | .356b
| ||
Housewife | 97 (59.9) | 117 (55.7) | ||
Employed | 51 (31.5) | 65 (31.0) | ||
Retired | 14 (8.6) | 28 (13.3) | ||
Menopause at beginning of the study
| 1 | .349b
| ||
Yes | 60 (37.0) | 68 (32.4) | ||
No | 102 (63.0) | 142 (67.6) | ||
Comorbidity
c
| 1 | .935b
| ||
Yes | 78 (48.1) | 102 (48.6) | ||
No | 84 (51.9) | 108 (51.4) | ||
Number of comorbidities
| 1 | .001b
| ||
One | 42 (26.0) | 30 (14.3) | ||
More than one | 36 (22.0) | 72 (34.3) |
Variable
|
n
|
Percent (%)
|
---|---|---|
Breast cancer
| ||
One side | 159 | 98.1 |
Two sides | 3 | 1.9 |
Biopsy before surgery
| ||
Yes | 96 | 59.3 |
No | 66 | 40.7 |
Type of surgery
| ||
Breast conservation | 72 | 44.4 |
Mastectomy | 90 | 55.6 |
Stage
| ||
0 | 4 | 2.5 |
I | 37 | 22.8 |
II | 80 | 49.4 |
III | 39 | 24.1 |
IV | 2 | 1.2 |
Chemotherapy
| ||
Yes | 128 | 79.0 |
No | 34 | 21.0 |
Radiotherapy
| ||
Yes | 122 | 75.3 |
No | 40 | 24.7 |
Hormonal therapy
| ||
Yes | 111 | 68.5 |
No | 51 | 31.5 |
Combined & single treatment modality
| ||
CT + RT + HT | 62 | 38.3 |
CT + RT | 35 | 21.6 |
CT + HT | 16 | 9.9 |
RT + HT | 23 | 14.2 |
CT | 15 | 9.3 |
RT | 1 | 0.6 |
HT | 10 | 6.2 |
Treatment at the 6-month follow-up
a
| ||
Ongoing treatment | 53 | 32.7 |
Treatment ended 1–2 weeks before follow-up | 75 | 46.3 |
Treatment ended more than 1 month before follow-up | 34 | 21.0 |
Variables
|
Range
|
BC
1
group mean (SD)
|
Differences within BC group
3
|
C
2
group mean (SD)
|
Differences within C group
3
|
Differences between groups
4
at T1
|
Differences between groups
4
at T2
| ||
---|---|---|---|---|---|---|---|---|---|
T1
|
T2
|
(p value)
|
T1
|
T2
|
(p value)
|
(p value)
|
(p value)
| ||
EORTCQLQ-C30:
| |||||||||
Global quality of life | 0-100 | 58.1(20.1) | 68.7 (18.5) |
.000
| 70.1 (21.6) | 72.4 (18.0) | .098 |
.000
| .053 |
Functional scales:
| |||||||||
Physical | 0-100 | 93.8 (9.6) | 77.4 (16.3) |
.000
| 85.5 (12.6) | 85.2 (12.7) | .713 |
.000
|
.000
|
Role | 0-100 | 94.6 (12.3) | 81.9 (19.3) |
.000
| 90.0 (16.4) | 88.2 (16.8) | .160 |
.002
|
.001
|
Emotional | 0-100 | 55.2 (27.4) | 65.3 (23.8) |
.000
| 72.5 (22.8) | 74.0 (21.6) | .335 |
.000
|
.000
|
Cognitive | 0-100 | 87.9 (15.1) | 83.3 (18.2) |
.009
| 82.5 (20.6) | 84.0 (19.2) | .261 |
.004
|
.716
|
Social | 0-100 | 82.2 (21.3) | 74.8 (24.6) |
.001
| 93.7 (14.5) | 93.3 (15.0) | .745 |
.000
|
.000
|
Symptom scales:
| |||||||||
Fatigue | 0-100 | 18.3 (18.4) | 31.6 (23.3) |
.000
| 21.0 (16.4) | 22.5 (19.3) | .234 | .130 |
.000
|
Nausea/vomiting | 0-100 | 4.2 (9.3) | 7.4 (16.2) |
.024
| 3.5 (9.1) | 3.3 (9.7) | .840 | .452 |
.005
|
Pain | 0-100 | 15.1 (17.4) | 25.0 (21.9) |
.000
| 15.9 (19.9) | 17.2 (19.9) | .342 | .699 |
.000
|
Dyspnea | 0-100 | 8.4 (17.1) | 11.3 (17.9) | .090 | 8.1 (16.7) | 9.4 (18.8) | .326 | .848 | .311 |
Insomnia | 0-100 | 22.0 (28.3) | 26.5 (29.7) | .076 | 18.1 (24.6) | 18.6 (24.4) | .788 | .162 |
.006
|
Appetite loss | 0-100 | 13.8 (23.1) | 13.7 (24.0) | .990 | 6.8 (15.0) | 7.6 (16.1) | .523 |
.001
|
.005
|
Constipation | 0-100 | 8.2 (19.0) | 15.2 (25.5) |
.001
| 12.8 (21.8) | 12.4 (21.3) | .761 |
.030
| .253 |
Diarrhea | 0-100 | 3.3 (11.3) | 3.5 (10.9) | .862 | 3.3 (10.0) | 4.8 (14.1) |
.217 | .970 | .347 |
Financial difficulties | 0-100 | 17.7 (29.0) | 37.9 (34.3) |
.000
| 10.3 (22.7) | 8.7 (19.4) | .309 |
.008
|
.000
|
Sense of Coherence
| 13-91 | 67.2 (11.3) | 63.1 (13.4) |
.000
| 61.9 (14.0) | 62.9 (13.4) | .171 |
.000
| .870 |
Spiritual Perspective Scale
| 10-60 | 54.5 (4.9) | 51.5 (6.5) |
.000
| 49.0 (7.5) | 49.2 (6.9) | .424 |
.000
|
.001
|
Religious Coping (+)
| 7-28 | 24.1 (4.2) | 22.8 (4.3) |
.000
| 22.8 (4.3) | 22.9 (4.2) | .684 | .004
| .806 |
Religious Coping (−)
| 7-28 | 11.5 (4.7) | 12.0 (4.9) | .135 | 12.3 (4.7) | 12.0 (4.2) | .322 | .072 | .927 |
Changes over time
Variables
|
GLM results
interaction effect
a
|
Statistical changes over time
(p value)
|
Adjusted mean differences between groups over time
b
(Clinical changes)
|
---|---|---|---|
Group * Time
|
T1 → T2
|
T1 → T2
| |
EORTCQLQ-C30:
| |||
Global quality of life | 12.5 |
.000
| +8.2 |
Functional scales:
| |||
Physical | 118.5 |
.000
|
- 16.2
|
Role | 30.1 |
.000
|
- 11.0
|
Emotional | 9.8 |
.002
| +8.5 |
Cognitive | 7.9 |
.005
| - 6.0 |
Social | 8.4 |
.004
| - 7.0 |
Symptom scales:
| |||
Fatigue | 22.7 |
.000
|
+12.0
|
Nausea/vomiting | 4.7 |
.030
| +3.4 |
Pain | 13.3 |
.000
| +8.6 |
Dyspnea | 0.6 | .419 | +1.7 |
Insomnia | 1.7 | .184 | +4.0 |
Appetite loss | 0.1 | .707 | - 1.0 |
Constipation | 8.6 |
.004
| +7.5 |
Diarrhea | 0.4 | .545 | - 1.1 |
Financial difficulties | 51.7 |
.000
|
+21.7
|
Sense of Coherence
| 17.3 |
.000
| - 6.5 |
Spiritual Perspective Scale
| 31.0 |
.000
| - 6.6 |
Religious Coping (+)
| 9.8 |
.002
| - 6.5 |
Religious Coping (−)
| 3.5 | .060 | +4.3 |
Predictors of HRQoL in the breast cancer group at T2
Dependent variables
|
\( \widehat{\boldsymbol{\upbeta}} \)
|
p value
|
Dependent variables
|
\( \widehat{\boldsymbol{\upbeta}} \)
|
p value
|
---|---|---|---|---|---|
Global quality of life
|
Pain
| ||||
Education | 0.21 |
.003
| Disease stage | 0.17 |
.032
|
SOC | 0.50 |
.000
| SOC | -0.26 |
.003
|
R
2
= 0.33 | PA-baseline | 0.20 |
.012
| ||
Physical Functioning
|
R
2
= 0.16 | ||||
Disease stage | -0.19 |
.012
|
Dyspnea
| ||
SOC | 0.31 |
.000
| DY-baseline | 0.26 |
.001
|
PF-baseline | 0.27 |
.000
|
R
2
= 0.16 | ||
R
2
= 0.26 |
Insomnia
| ||||
Role Functioning
| SOC | -0.39 |
.000
| ||
Disease stage | -0.17 |
.036
| SL-baseline | 0.36 |
.000
|
SOC | 0.33 | .000
|
R
2
= 0.30 | ||
R
2
= 0.19 |
Appetite Loss
| ||||
Emotional Functioning
| Education | -0.27 |
.001
| ||
Surgery type | -0.22 |
.001
| Disease stage | 0.17 |
.034
|
SOC | 0.49 |
.000
| SOC | -0.27 |
.001
|
R
2
= 0.40 |
R
2
= 0.17 | ||||
Cognitive Functioning
|
Constipation
| ||||
Age | 0.16 |
.041
| CO-baseline | 0.25 |
.001
|
SOC | 0.26 | .002
|
R
2
= 0.13 | ||
RCOPE (−) | -0.17 |
.034
|
Diarrhea
| ||
R
2
= 0.21 | Disease stage | 0.27 |
.001
| ||
Social Functioning
|
R
2
= 0.12 | ||||
SOC | 0.33 |
.000
|
Financial Difficulties
| ||
R
2
= 0.25 | SOC | -0.26 |
.002
| ||
Fatigue
| FI-baseline | 0.28 |
.000
| ||
Disease stage | 0.15 |
.041
|
R
2
= 0.24 | ||
SOC | -0.36 |
.000
| |||
FA-baseline | 0.21 |
.005
| |||
R
2
= 0.25 |