Participant Characteristics
From the parent sample of 327 women with breast cancer, 98 participants (30.0%) self-identified as Black or African-American. The number of women who identified as Black or African-American enrolled in the parent study was representative of the population served by the treating cancer clinics based on clinic catchment area statistics. The current study used this sub-sample of women identifying as Black or African-American for the analyses. The average age of women in this sub-sample was 57.22 (SD=10.87) years. Approximately one-third (36%) of participants reported “at least some college”; nearly half (44%) of participants reported household income of up to $39,000/year. For nearly all women (97%), this was their first breast cancer diagnosis. Forty-nine participants (50%) had stage 1 disease. Additional demographic and medical characteristics are reported in Tables 1 and 2, respectively. Participant reported pain severity (M=4.59; SD=1.90) and interference (M=4.52; SD=2.59) were in the moderate range. Additional variable means and correlations are reported in Table 3.
Table 1
Demographic Characteristics (N=98)
|
N (%)
|
M (SD)
|
Age (years)
|
|
57.22 (10.78)
|
Race
|
|
|
Black or African-American
|
98 (100%)
|
|
Ethnicity
|
|
|
Non-Hispanic
|
98 (100%)
|
|
Education
|
|
|
Less than High School Diploma
|
5 (5.1%)
|
|
High School Diploma
|
16 (16.3%)
|
|
Some College
|
35 (35.7%)
|
|
Bachelor’s Degree
|
24 (24.5%)
|
|
Graduate Degree
|
18 (18.4%)
|
|
Income
|
|
|
Less than $10,000
|
7 (7.2%)
|
|
$10,000 to $19,999
|
14 (14.4%)
|
|
$20,000 to $39,999
|
22 (22.7%)
|
|
$40,000 to $59,999
|
28 (28.9%)
|
|
$60,000 to $100,000
|
18 (18.6%)
|
|
More than $100,000
|
8 (8.2%)
|
|
Note. M = mean; SD = standard deviation. |
Table 2
Medical Characteristics (N=98)
|
N (%)
|
M (SD)
|
Cancer Diagnosis
|
|
|
First/Initial
|
95 (96.9%)
|
|
Recurrence
|
3 (3.1%)
|
|
Months Since Diagnosis
|
|
10.39 (6.42)
|
Stage
|
|
|
I
|
49 (50.0%)
|
|
II
|
39 (39.8%)
|
|
III
|
10 (10.2%)
|
|
Mastectomy (one breast only)
|
|
|
Yes
|
18 (18.8%)
|
|
No
|
78 (81.3%)
|
|
Mastectomy (both breasts)
|
|
|
Yes
|
12 (12.5%)
|
|
No
|
84 (87.5%)
|
|
Breast Conserving Surgery
|
|
|
Yes
|
57 (59.4%)
|
|
No
|
39 (40.6%)
|
|
Lymph Node Removal
|
|
|
Yes
|
15 (15.6%)
|
|
No
|
81 (84.4%)
|
|
Reconstructive Surgery
|
|
|
Yes
|
13 (13.5%)
|
|
No
|
83 (86.5%)
|
|
Use of Antidepressant Medication
|
|
|
Yes
|
27 (27.6%)
|
|
No
|
71 (72.4%)
|
|
Note. M = mean; SD = standard deviation; Breast Conserving Surgery = lumpectomy, quadrantectomy, partial mastectomy, segmental mastectomy. |
Table 3
Means (M), Standard Deviations (SD), and Correlation Matrix for Main Study Variables (N=98)
Variable
|
Pain Severity
|
Pain Interference
|
Pain Self-Efficacy
|
Depressive Symptoms
|
M (SD)
|
4.59 (1.90)
|
4.52 (2.59)
|
60.14 (22.24)
|
17.20 (10.91)
|
Pain Severity
|
1
|
-
|
-
|
-
|
Pain Interference
|
.73**
|
1
|
-
|
-
|
Pain Self-Efficacy
|
-.50**
|
-.55*
|
1
|
-
|
Depressive Symptoms
|
.36**
|
.59**
|
-.47**
|
1
|
Note. M = mean; SD = standard deviation; Fatigue scores shown as T-score; *p<.05; **p<.01. |
Table 4
Predictors of Pain Severity and Pain Interference
|
Pain Severity
|
Pain Interference
|
|
B
|
p
|
95% CI
(Lower, Upper Bounds)
|
β
|
B
|
p
|
95% CI
(Lower, Upper Bounds)
|
β
|
Model 1
|
|
|
|
|
|
|
|
|
Education Level
|
2.27
|
<.01
|
.64, 3.90
|
.27
|
2.34
|
<.05
|
.39, 4.29
|
.20
|
Depressive Symptoms
(with covariates)
|
.06
|
<.001
|
.02, .09
|
.32
|
.13
|
<.001
|
.09, .17
|
.55
|
Model 2
|
|
|
|
|
|
|
|
|
Education Level
|
2.24
|
<.01
|
.69, 3.79
|
.26
|
2.30
|
<.05
|
.26, 4.34
|
.20
|
Self-Efficacy
(with covariates)
|
-.04
|
<.001
|
-.05, -.02
|
-.44
|
-.06
|
<.001
|
-.08, -.04
|
-.53
|
Note: Models 1 and 2 regression analyses included covariates of age, cancer stage, and education level. Only significant predictors shown. Education Level = less than high school diploma vs. some college.
|
Relationship between Depressive Symptoms and Pain Severity and Pain Interference
Without covariates in the regression models, depressive symptoms were significantly related to both pain severity (B=.06, p<.001, 95% CI [.03, 1.00], β = .36) and pain interference (B=.14, p<.001, 95% CI [.10, .18], β = .59), such that higher depressive symptoms were associated with higher pain severity and higher pain interference.
Once covariates were added to the regression models, depressive symptoms remained significantly related to both pain severity (B=.06, p<.01, 95% CI [.02, .09], β = .32) and pain interference (B=.13, p<.001, 95% CI [.09, .17], β = .55). Adding depressive symptoms to the regression models explained an additional 9.0% (p<.01) and 27.6% (p<.001) of the variance in pain severity and pain interference, respectively, above and beyond the covariates. The dummy code comparing “less than high school diploma” to “some college” was a significant predictor of both pain severity (B=2.27, p<.01, 95% CI [.64, 3.90], β = .27) and pain interference (B=2.34, p<.05, 95% CI [.39, 4.29], β = .20). These results indicate that, on average, women reporting “less than high school diploma” endorsed pain severity and pain interference 2.27 and 2.34 higher than those reporting “some college,” respectively. Age and cancer stage were not significantly related to pain.
Relationship between Self-Efficacy for Pain Management and Pain Severity and Pain Interference
Without covariates in the regression models, self-efficacy for pain management was significantly related to both pain severity (B=-.04, p<.001, 95% CI [-.06, -.03], β=-.50) and pain interference (B=-.06, p<.001, 95% CI [-.08, -.04], β=-.55), such that lower self-efficacy for pain management was associated with higher pain severity and higher pain interference.
Once covariates were added to the regression models, self-efficacy for pain management remained significantly related to both pain severity (B=-.04, p<.001, 95% CI [-.05, -.02], β=-.44) and pain interference (B=-.06, p<.001, 95% CI [-.08, -.04], β=-.53). Adding pain self-efficacy to the regression models explained an additional 15.6% (p<.001) and 21.1% (p<.001) of the variance in pain severity and pain interference, respectively, above and beyond the covariates. The dummy code comparing “less than high school diploma” to “some college,” was a significant predictor of both pain severity (B=2.24, p<.01, 95% CI [.69, 3.79], β = .26) and pain interference (B=2.30, p<.05, 95% CI [.26, 4.34], β = .20). These results indicate that, on average, women reporting “less than high school diploma” endorsed pain severity and pain interference 2.24 and 2.30 higher than those reporting “some college,” respectively. Age and cancer stage were not significantly related to pain.