Abstract
Background
Physical activity (PA) is recommended for women with breast cancer; however, data are sparse on the association of PA with quality of life and patient-reported symptoms for women on adjuvant endocrine therapy (AET).
Methods
Women with hormone receptor positive breast cancer taking AET completed standardized surveys about their health-related quality of life (HRQoL), AET-related symptoms, and levels of PA using validated measures. Wald X2 and ANOVA were used to assess associations with PA and independent variables. Generalized linear regession analyses assessed assocations between PA, quality of life, and AET-related symptoms.
Results
The analytic cohort included 588 Black and White women. Black race, high BMI, and being on aromatase inhibitors (vs. Tamoxifen) were associated with lower PA in bivariate analysis. In multivariate analysis, lower self-reported PA was associated with high BMI (p=0.002) and chemotherapy uptake (p=0.006). Better HRQoL (p=0.01),lower overall AET related symptoms (p=0.02), and lower gynecological symptoms (p=0.03) were associated with increasing levels of moderate physical activity.
Conclusion
Among women taking AET, moderate levels of PA may be associated with fewer medication related symptoms and overall better ratings of HRQoL. Given the low levels of PA observed in the sample overall and particularly for Black women, identifying successful strategies to promote PA are needed.
Keywords: Exercise, Breast Neoplasms, Quality of Life, Therapeutics
PRECIS:
Among women taking AET, moderate levels of PA may be associated with fewer medication related symptoms and overall better ratings of HRQL. Given the low levels of PA observed in the sample overall and particularly for Black women, identifying successful strategies to promote PA are needed.
Introduction
Breast cancer (BC) is the leading cause of cancer among women worldwide.1 Advances in early detection and targeted therapies for BC such as adjuvant endocrine therapy (AET) for hormone receptor positive (HR+) BC, have led to improved survival.2 Because women with HR+ breast cancer are recommended to take AET for at least five years,3 many women contend with treatment-related toxicities over the long-course of therapy.4,5Women taking AET often report symptoms related to their medication such as weight gain, hot flushes, bone, or joint pain and lower quality of life (QOL).6
Physical activity (PA) among BC survivors is associated with several positive health outcomes such as enhanced quality of life,7 reduction in chronic pain,8 and weight loss and decreased body mass index (BMI) leading to improved physical function.9 PA may reduce medication-related symptoms in women taking AET.10,11 The American Cancer Society (ACS) recommends cancer survivors engage in at least 150 minutes of moderate- or 75 minutes of vigorous-intensity PA per week.12 Unfortunately, most survivors fail to meet these recommedations.13–15 Given established benefits of regular PA for a range of toxicities (eg physical, mental, social, etc.) it is important to examine PA among women with HR+ BC and relationships with AET-related symptoms.10,16
Most studies of PA in breast cancer survivors have not examined the relationship between AET-related symptoms in women who are HR+ and there has been low representation of African Americans survivors.17–19 Further, there is a dearth in the literature with regard to factors that may be associated with PA levels in African American women. For example, social support has been shown to be a key contributor to healthy behaviors, including PA; however, data are lacking for racial/ethnic minorities.20,21 This report aims to fill gaps in knowledge of the relationship between PA and quality of life. Particularly, in this study we will 1) characterize PA levels based on sociodemographic (e.g. race, education), clinical (body mass index, AET type) and psychosocial (e.g. emotional support, tangible support ) factors and 2) assess the relationship between PA and quality of life and AET-related symptoms (e.g. gynecological, gastrointestinal) in a diverse cohort of HR+ BC survivors. We hypothesize that we will observe significantly higher levels of PA in White women (vs. Black women), women taking Tamoxifen (vs. women on aromatase inhibitors) women with lower BMI (vs. higher BMI) and women who report greater emotional and tangible support. In addition, we hypothesize that more severe AET-related symptoms and lower QOL will be significantly related to lower levels of PA. Findings may have the potential to inform barriers of PA participation in BC survivors, so interventions can best promote PA a group of women who have prolonged therapy that often adversely impacts their quality of life.
METHODS
Setting and Sample
This is a secondary analysis of the data from the Women’s Hormonal Initiation and Persistence (WHIP) study, an observational trial of women taking AET. A secondary aim of WHIP was to identify factors that may be associated with patient reported AET-related symptoms and overall quality of life. WHIP recruitment and data collection methods have been described previously.22 Briefly, women diagnosed with BC were identified from academic medical centers, integrated health systems, and via community outreach. Eligibility criteria included: being within 12 months of a diagnosis of hormonal receptor (HR) positive breast cancer (confirmed via lab reports), ≥ 18 years old, having initiated AET, and ability to speak English or Spanish. Women were deemed as potentially eligible in medical centers, integrated health systems based on cancer registry, and pharmacy records. These women were mailed letters that described the study protocol and were asked to call a toll-free number or to return a stamped self-addressed postcard if they did not want to be contacted about the study. Women recruited via community outreach were screened for eligibility by a clinical research assistant (CRA). Research assistants contacted women who did not opt out within a two-week time frame, confirmed level of interest, consented interested participants, and scheduled phone interviews to complete the survey.
Data were collected via standardized telephone surveys (REDCap) that were administered according to a woman’s preference via a trained CRA or via a secure on-line survey.23
The baseline cohort included 592 women. Women were excluded from this analysis if they were missing PA data (N=37) or had incomplete data for QOL or treatment-associated symptom scores (N=29). An additional 31 women who reported being a race/ethnicity other than non-Hispanic White or non-Hispanic Black were excluded due to limited numbers to sufficiently evaluate other racial/ethnic groups. An additional N=10 were excluded due to missing covariate data. Those excluded for missing data were generally similar to those included in the present analysis. Excluded participants were somewhat less likely to have received chemotheraphy, were less likely to have borderline Human Epidermal growth factor Receptor 2 (HER2) status and more likely to have HER2 negative status and were less likely to report an income ≥$100,000/year. The final analytic cohort consisted of 485 non-Hispanic White (N=349) and non-Hispanic Black (N=136) breast cancer survivors.
Measures
PA was measured using the International Physical Activity Questionnaire, short form (IPAQ-SF).24,25 Participants are asked to self-report PA in the previous 7 days. This 7-item IPAQ assesses the time spent per week sitting, walking, or participating in moderate- (e.g., carrying light loads, bicycling at a regular pace) and vigorous-intensity (heavy lifting, aerobics) activities. PA was evaluated as a categorical variable and was assessed as levels of moderate physical activity (None, <60 minutes/week, ≥60 minutes/week), vigorous physical activity (None, <60 minutes/week, ≥60 minutes/week), and total physical activity (<60 minutes/week, 60-<120 minutes/week, ≥120 minutes/week), which also included walking.
Quality of life was measured using two previously-validated Functional Assessment of Cancer Therapy (FACT) questionnaires – FACT-B, which is specific to breast cancer, and FACT-Endocrine Subscale (ES) a symptom specific scale.26 Four subscales, physical wellbeing (FACT-PWB) (Cronbach alpha = 0.66), social/family wellbeing (FACT-SWB) (Cronbach alpha = 0.67), emotional wellbeing (FACT-EWB) (Cronbach alpha = 0.63), and functional wellbeing (FACT-FWB) (Cronbach alpha = 0.55), comprise the FACT-B. The FACT-B scale ranges from 0 to 123 (Cronbach alpha = 0.76). Higher FACT-B scores indicate better health-related quality of life. Quality of life and AET symptoms scores were evaluated for total scores and by subscales. Quality of life scores (FACT-B, FACT-EWB, FACT-PWB, FACT-SWB,FACT-FWB) and AET symptom scores (ES-overall (Cronbach alpha = 0.79), vasomotor, neurological, gastrointestinal, gynecological) were assessed as continuous variables. Higher FACT-B scores indicated higher ratings of QOL, and higher AET scores indicated more AET-related symptoms.
The Medical Outcome Study (MOS) Social Support Questionnaire was used to assess participants’ ratings of support, using two subscales (emotional/informational(Cronbach alpha = 0.93), tangible (Cronbach alpha = 0.92)).27
Clinical variables included body mass index (BMI), clinical stage at diagnosis (0, I, II, III/IV), HER2 status, type of AET (e.g. anastrozole, tamoxifen), chemotherapy (yes, no), radiation (yes, no), and surgery (none/unknown, lumpectomy, mastectomy). We also assessed number of comorbidities, time since AET initiation, and time since diagnosis. Sociodemographic variables included age, self-identified race, marital status, educational level, income, and employment status.
Statistical Analysis
Differences in total PA levels by sociodemographic, body composition, cancer stage and treatment history were evaluated using Wald X2 tests. Two-way analysis of variance (ANOVA) was used to calculate mean scores and standard deviation across categories of population characteristics and assess associations between population characteristics and scores.
Generalized linear regression models were used to assess associations between PA levels and quality of life and endocrine symptoms. Mean scores and 95% confidence intervals were calculated using unadjusted regression models. Multivariable-adjusted regression models included the following covariates: age (continuous), race (black, white), marital (married/living with partner, single/divorced/widowed), education (≤ high school, ≥ some college), income (<$60,000, $60,000 - <$100,000, ≥$100,000, Unknown), body mass index (<25, 25 - <30, ≥30 kg/m2), cancer stage (0, I, II, III/IV, unknown), comorbidities (1, >1, unknown), time since diagnosis (≤1 year, >1 year, unknown), time since AET initiaton (≤6 months, >6 months, unknown), tangible support (score ≤15, 16–19, >19), emotional/informational support (score ≤31, 32–39, >39). Variables included in the final adjusted model were chosen a priori based on factors previously reported to be associated with PA levels, quality of life or endocrine symptom; and multicollinearity was not detected. Multicollinearity was assessed using condition indices calculated using the COLLIN option in PROC REG procedure in SAS software.28 Statistical significance is defined as P<0.05. Two-sided P-values are reported. Analyses were conducted using SAS 9.3 (SAS Institute, Inc.) software.
RESULTS
A total of 485 survivors were included in this analysis. Black survivors comprised 28% of our sample (Table 1). A majority of survivors were married or living with a partner (64.9%), had at least some college education (86.4%), and worked full-time (40.2). Most surviors had a lumpectomy (39.0%) were taking aromatase inhibitors (56.0%), had a BMI ≥30 kg/m2 (40.6%). With regard to psychosocial factors, most survivors reported moderate levels of emotional/information (40.1%) and high levels of tangible support (41.0%).
Table 1.
Socio-demographic and Clinical Characteristics and Physical Activity Levels among Non-Hispanic Black and White Breast Cancer Survivors
| TOTAL PHYSICAL ACTIVITY | |||||
|---|---|---|---|---|---|
| <60 minutes/week | 60 - <120 minutes/week | ≥ 120 minutes/week | P-valuea | ||
| N (%) | N (%) | N (%) | N (%) | ||
| Overall | 485 (100) | 231 (47.6) | 135 (27.8) | 119 (24.5) | 0.2 |
| Ageb | |||||
| <55 years | 182 (37.5) | 77 (42.3) | 57 (31.3) | 48 (26.4) | |
| 55 - <65 years | 158 (32.6) | 76 (48.1) | 47 (29.8) | 35 (22.2) | |
| ≥65 years | 145 (29.9) | 78 (53.8) | 31 (21.4) | 36 (24.8) | |
| Race | 0.01 | ||||
| Black | 136 (28.0) | 79 (58.1) | 32 (23.5) | 25 (18.4) | |
| White | 349 (72.0) | 152 (43.6) | 103 (29.5) | 94 (26.9) | |
| Marital Status | 0.05 | ||||
| Married/Living with Partner | 314 (64.9) | 137 (43.6) | 96 (30.6) | 81 (25.8) | |
| Divorced/Widowed / Single | 170 (35.1) | 94 (55.3) | 39 (22.9) | 37 (21.8) | |
| Educational Level | 0.01 | ||||
| ≤ High School | 61 (12.6) | 39 (63.9) | 8 (13.1) | 14 (23.0) | |
| ≥ Some college | 419 (86.4) | 192 (45.8) | 125 (29.8) | 102 (24.3) | |
| Employment Status | 0.03 | ||||
| Full-Time | 194 (40.2) | 85 (43.8) | 62 (32.0) | 47 (24.2) | |
| Part-Time | 85 (17.6) | 32 (37.7) | 31 (36.5) | 22 (25.9) | |
| Retired | 143 (29.7) | 77 (53.9) | 29 (20.3) | 37 (25.9) | |
| Otherc | 60 (12.4) | 36 (60.0) | 12 (20.0) | 12 (20.0) | |
| Income | 0.001 | ||||
| <$60,000 | 142 (29.3) | 85 (59.9) | 21 (14.8) | 36 (25.4) | |
| $60,000- <100,000 | 127 (26.2) | 61 (48.0) | 36 (28.4) | 30 (23.6) | |
| ≥$100,000 | 190 (39.2) | 73 (38.4) | 69 (36.3) | 48 (25.3) | |
| Unknownd | 26 (5.4) | 12 (46.2) | 9 (34.6) | 5 (19.2) | |
| Time since Diagnosis | 0.54 | ||||
| ≤ 1 year | 49 (10.1) | 23 (46.9) | 13 (26.5) | 13 (26.5) | |
| > 1 year | 384 (79.2) | 186 (49.6) | 109 (28.3) | 89 (22.1) | |
| Unknown | 52 (10.7) | 22 (42.3) | 13 (25.0) | 17 (32.7) | |
| Stage at Diagnosis | 0.67 | ||||
| Stage 0 | 14 (2.9) | 8 (57.1) | 4 (28.6) | 2 (14.3) | |
| Stage I | 235 (48.5) | 109 (46.4) | 65 (27.7) | 61 (26.0) | |
| Stage II | 114 (23.5) | 59 (51.8) | 32 (28.1) | 23 (20.2) | |
| Stage III/IV | 30 (6.2) | 17 (56.7) | 8 (26.7) | 5 (16.7) | |
| Missing/Unknown | 92 (19.0) | 38 (41.3) | 26 (28.3) | 28 (30.4) | |
| Her2 Status | 0.03 | ||||
| Unknown | 220 (45.4) | 96 (43.6) | 75 (34.1) | 49 (22.3) | |
| Negative | 205 (42.3) | 99 (48.3) | 49 (23.9) | 57 (27.8) | |
| Borderline | 41 (8.5) | 26 (63.4) | 9 (22.0) | 6 (14.6) | |
| Positive | 19 (3.9) | 10 (52.6) | 2 (10.5) | 7 (36.8) | |
| Time since AET initiation | 0.03 | ||||
| ≤ 6 months | 199 (41.0) | 101 (53.1) | 54 (27.0) | 44 (20.0) | |
| > 6 months | 221 (45.6) | 105 (47.5) | 54 (24.4) | 62 (28.1) | |
| Unknown | 65 (13.4) | 25 (38.5) | 27 (41.5) | 13 (20.0) | |
| AET Medication | 0.01 | ||||
| Aromatase Inhibitorg | 258 (56.0) | 151 (53.0) | 57 (32.4) | 50 (28.4) | |
| Tamoxifen | 203 (44.0) | 69 (39.2) | 68 (23.9) | 66 (23.2) | |
| Chemotherapy | 0.04 | ||||
| Yes | 120 (24.7) | 65 (54.2) | 23 (19.2) | 32 (26.7) | |
| No | 142 (29.3) | 64 (45.1) | 37 (26.1) | 41 (28.9) | |
| Unknown | 223 (46.0) | 102 (45.7) | 75 (33.6) | 46 (20.6) | |
| Radiation Treatment | 0.01 | ||||
| Yes | 214 (44.1) | 109 (50.9) | 48 (22.4) | 57 (26.6) | |
| No | 74 (15.3) | 41 (55.4) | 15 (20.3) | 18 (24.3) | |
| Unknown | 197 (40.6) | 81 (41.1) | 72 (36.6) | 44 (22.3) | |
| Surgery Typeh | 0.07 | ||||
| None/Unknown | 144 (29.7) | 59 (41.0) | 53 (36.8) | 32 (22.2) | |
| Lumpectomy | 189 (39.0) | 98 (51.9) | 43 (22.8) | 48 (25.4) | |
| Mastectomy | 152 (31.3) | 74 (48.7) | 39 (25.6) | 39 (25.6) | |
| Body Mass Index | <0.001 | ||||
| <25 kg/m2 | 162 (33.9) | 54 (33.3) | 55 (34.0) | 53 (33.7) | |
| 25 - <30 kg/m2 | 122 (25.5) | 62 (50.8) | 36 (29.5) | 24 (19.7) | |
| ≥30 kg/m2 | 194 (40.6) | 109 (56.2) | 44 (22.7) | 41 (21.1) | |
| Comorbidities | 0.0003 | ||||
| 1 | 24 (4.9) | 13 (54.2) | 5 (20.8) | 6 (25.0) | |
| > 1 | 219 (45.2) | 121 (57.3) | 41 (18.6) | 57 (24.1) | |
| Unknown | 242 (49.9) | 97 (40.1) | 89 (36.8) | 56 (23.1) | |
| Emotional/Informational Supporte | 0.84 | ||||
| ≤31 | 121 (24.9) | 60 (49.6) | 32 (26.5) | 29 (24.0) | |
| 32 – 39 | 243 (40.1) | 119 (49.0) | 66 (27.2) | 58 (23.9) | |
| >39 | 121 (24.9) | 52 (43.0) | 37 (30.6) | 32 (26.5) | |
| Tangible Support Scalef | 0.68 | ||||
| ≤15 | 130 (26.8) | 56 (43.1) | 40 (30.8) | 34 (26.2) | |
| 16 – 19 | 156 (32.2) | 73 (47.8) | 45 (28.9) | 38 (24.4) | |
| >19 | 199 (41.0) | 102 (51.3) | 50 (25.1) | 47 (23.6) | |
Wald X2 Test
Quartiles.
Full-time home-maker or family caregiver, unemployed, but seeking employment, student, other or refused to answer.
Respondent did not know or refused to answer.
Tertiles. Score range: 8 – 40. Higher score=better emotional support.
Tertiles. Score range: 4 – 20. Higher score=better tangible support.
Aromatase Inhibitors included: Anastrozole, Exemestane, Letrozole.
No surgery N=3; Missing/Unknown N=155; Mastectomy category includes women who reported having both a lumpectomy and mastectomy N=16
Associations of total PA with sociodemographic and breast cancer-related clinical/pathological variables among Black and White breast cancer survivors are presented in Table 1. Black survivors and those with low educational attainment, retired/unemployed, and low annual income were more likely to report low total PA (<60 minutes/week). Among clinical factors, high BMI at diagnosis, more recent AET initiation, being on aromatase inhibitors compared to tamoxifen, and having received chemotherapy were also associated with lower total PA. Additionally, women who initatied AET six months or less from interview compared to those who initated greater than six months from interview and women with more than one comorbidity compared to those with one comorbidity reported lower total PA. In generalized linear models with PA as the dependent continuous variable and after adjusting for all sociodemographic variables shown in Table 1, only BMI (P=0.02) and chemotherapy (P=0.006) were significantly associated with self-reported total PA.
Better QOL, as determined by higher scores on FACT-B, were associated with increasing age, White race, being married/living with a partner, and higher socioeconomic status (results not shown). Additionally, patients with higher BMI at diagnosis, and those reporting non-surgical treatment and chemotherapy for their breast cancer had significantly lower scores for both FACT-B. However, QOL scores did not differ between tamoxifen users and those on aromatase inhibitors. Patients diagnosed at later stages (III/IV) also reported lower QOL scores than those diagnosed at earlier stages (P=0.21). Social support, as measured by emotional/informational support and tangible support, was strongly associated with QOL (P<0.001). Given that social wellbeing might be correlated with the support scale questions, we rescored the QOL data without the social wellbeing component. Social support was still strongly associated with QOL (P<0.001). Associations of social support with QOL were strongest for the functional, emotional, and social wellbeing subscales and also for the BCS subscale (all P<0.001).
Patient reported AET symptoms were higher for survivors under the age of 65, Black women, those with less than a college education, those retired or unemployed, and those with obesity. Treatment modalities (e.g. chemotherapy, radiation) were not strongly associated with AET symptoms but there was some evidence of higher symptoms among women who reported undergoing chemotherapy. Women reporting higher emotional support had lower endocrine symptoms (P=0.03) but tangible support was not statistically significantly associated with symptoms.
In bivariate analyses, increasing total PA was associated with better QOL and lower AET symptoms among survivors. However, the differences were not statistically significant for FACT-B or AET symptom scores, suggesting a stronger relationship betweenf PA and functional and physical wellbeing, than with emotional or social wellbeing and AET-related symptoms.
In multivariate analyses adjusted for sociodemographic, social support, and clinical variables, increasing levels of moderate activity were associated with better QOL (P=0.02) (Table 2), lower overall AET-related symptoms (P=0.03), and lower gynecological symptoms (p=0.02) (Table 3). Compared to those reporting no activity, survivors reporting ≥ 60 minutes /week of moderate activity had 4% (P=0.01) higher FACT-B scores. Similar results were obtained for the association of QOL with vigorous activity but the results for FACT-B or overall AET-related symptoms were no longer significant in multivariate models (Tables 2 and 3).
Table 2.
Physical activity levels among breast cancer survivors and quality of life
| N | Overall Quality of Life Parameter Estimate (Standard Deviation) | |
|---|---|---|
| Physical Activity Level | ||
| Vigorous Activity | ||
| None | 329 | REF |
| <60 min/week | 101 | 2.96 (2.23) |
| ≥60 min/week | 55 | 2.67 (2.72) |
| P=0.09a | ||
| Moderate Activity | ||
| None | 190 | REF |
| <60 min/week | 215 | 5.80**(2.00) |
| ≥60 min/week | 80 | 4.69**(1.50) |
| P=0.01a | ||
| Total Physical Activity | ||
| <60 min/week | 231 | REF |
| 60 - <120 min/week | 135 | 3.40 (1.74) |
| ≥120 min/week | 119 | 1.56 (1.68) |
| P=0.14a | ||
Abbreviations: ACS=American Cancer Society; CI=confidence interval; ES=Endocrine Symptoms Scale
Test for linear regression parameter estimate=0
P<0.05
P<0.001
P<0.0001
Multivariable-adjusted regression model. Covariates: age (continuous), race (black, white), marital (married/living with partner, single/divorced/widowed), education (≤ high school, ≥ some college), income (<$60,000, $60,000 - <100,000, ≥$100,000, Unknown), body mass index (<25, 25 - <30, ≥30 kg/m2), cancer stage (0, I, II, III/IV, unknown), comorbidities (1, >1, unknown), Time since AET initiation (≤6months, >6 months, unknown), Time since diagnosis (≤1 year, >1 year, unknown), tangible support (score ≤15, 16–19, >19), emotional/informational support (score ≤31, 32–39, >39).
Table 3.
Multiple Regression of Physical Activity Levels and Overall AET Symptoms and Symptom Domains in Breast Cancer
| Symptom Domain | ||||||
|---|---|---|---|---|---|---|
| N | Overall ES | Vasomotor | Neurological | Gastrointestinal | Gynecological | |
| Parameter Estimate (Standard Deviation) | ||||||
| VIGOROUS ACTIVITY | ||||||
| None | 329 | REF | REF | REF | REF | REF |
| <60 min/week | 101 | −1.56(1.73) | −0.25(0.58) | −0.16(0.45) | −0.37(0.52) | −0.43(0.62) |
| ≥60 min/week | 55 | −2.61(1.33) | −0.35(0.45) | −0.33(0.35) | −0.41(0.40) | −1.16*(0.48) |
| P=0.13 | P=0.70 | P=0.63 | P=0.52 | P=0.05 | ||
| MODERATE ACTIVITY | ||||||
| None | 190 | REF | REF | REF | REF | REF |
| <60 min/week | 215 | −2.87(1.56) | −0.73(0.52) | −0.46(0.41) | −0.73(0.47) | −0.55(0.56) |
| ≥60 min/week | 80 | −3.43**(1.17) | −0.85*(0.39) | −0.59(0.31) | −0.57(0.35) | −1.13**(0.42) |
| P=0.02 | P=0.08 | P=0.43 | P=0.17 | P=0.03 | ||
| TOTAL PHYSICAL ACTIVITY | ||||||
| None | 231 | REF | REF | REF | REF | REF |
| <60 min/week | 135 | −1.99(1.35) | −0.68(0.45) | 0.13(0.35) | −0.42(0.40) | −0.65(0.48) |
| ≥60 min/week | 119 | −2.06(1.30) | −0.55(0.43) | 0.02(0.34) | −0.31(0.39) | −0.82(0.47) |
| P=0.18 | P=0.24 | P=0.93 | P=0.52 | P=0.16 | ||
Abbreviations: ACS=American Cancer Society; CI=confidence interval; ES=Endocrine Symptoms Scale
Test for linear regression parameter estimate=0
P<0.05
P<0.001
P<0.0001
Multivariable-adjusted regression model. Covariates: age (continuous), race (black, white), marital (married/living with partner, single/divorced/widowed), education (≤ high school, ≥ some college), income (<$60,000, $60,000 - <100,000, ≥$100,000, Unknown), body mass index (<25, 25 - <30, ≥30 kg/m2), cancer stage (0, I, II, III/IV, unknown), comorbidities (1, >1, unknown), Time since AET initiation (≤6months, >6 months, unknown), Time since diagnosis (≤1 year, >1 year, unknown), tangible support (score ≤15, 16–19, >19), emotional/informational support (score ≤31, 32–39, >39).
DISCUSSION
This observational study of Black and White HR+ BC survivors examined associations of PA with HRQOL and AET-related symptoms. A majority of the survivors (84%) did not meet the PA recommendations for cancer survivors from the ACS.12 Additionally, nearly half (47.6%) of the survivors in the study had PA levels less than one hour per week underscoring the need to improve PA in this group of survivors. Results suggested lower QOL and higher endocrine symptoms with cancer among young survivors, Black survivors and those with low SES. Moderate PA was associated with better QOL and lower AET symptoms in breast cancer survivors in multivariable adjusted models.
Given that most HR+ BC survivors will be prescribed to take AET for at least five years, identifying targets to enhance QOL is a priority. There has been limited empirical data about AET-related symptoms and PA in diverse BC Survivors so this study begins to fill gaps in this area. While the overall level of PA was low, among women with moderate PA, QOL appeared higher and AET-related symptoms were lower.
Results from this study suggest a more consistent effect of moderate PA than vigorous PA. Although both moderate and vigorous (or a combination of the two) aerobic exercise are recommended for cancer survivors,12 moderate intensity activity might be more feasible to achieve in survivors not currently meeting PA recommendations. This is, in part, due to the fact that most survivors have low levels of PA at diagnosis, fail to meet recommended PA after treatment, and may endure physical limitations to vigorous PA.29,30 In addition, walking, which accounts for the majority of self-reported moderate intensity activity, is more precisely reported than vigorous intensity activities.31,32 In our sample, less severe overall AET-related, gynecological, and vasomotor symptoms were associated with performing at least 60 minutes of moderate PA per week. To our knowledge, this finding has not been previously reported; however, given the symptoms within the aforementioned domains (e.g. hot flashes, vaginal itching/irritation), it is possible that such symptoms may serve as barriers to varying levels of PA. Finally, residual confounding by diet and other “healthy lifestyle” factors that are associated with PA intensity cannot be ruled out as an explanation. Achieving moderate levels of PA may be an attainable goal for many women taking AET. Moderate level of PA also appears to be practical given that it includes a range of activities as part of daily living (heavy cleaning, mowing the lawn, walking, etc.).
Similar to other reports, Black survivors reported lower levels of PA across all categories compared to White survivors.33,34 Reasons for lower PA are not well elucidated in this population but may include negative attitudes about exercise, lack of access to facilities and lack of time.35–37 Future studies that examine the level and type of PA in Black women are needed to inform interventions. Nearly half (47.6%) of survivors in the study had PA levels less than one hour per week.
The are several strengths of this study such as its focus on HR+ survivors, inclusion of substantial proportion of Black HR+ survivors, and use of vetted measures that are clinically relevant to survivors (eg Functional Assessment of Chronic Illness (FACIT)). However, several limitations should be noted. First, given the cross-sectional design we cannot determine causality. Future studies will enable assessment of long-term impact of PA. Additionally, it is possible that those with most severe symptoms may have prematurely quit therapy though at the time of data collection all women were currently taking AET. Next, findings may not be generalizable to survivors with other BC subtypes (i.e., triple negative, etc.). However, the focus of this study was to examine relationships between PA and women taking AET. Similar studies in other BC subtypes groups will be important in the future. PA was based on self-report and not collected via observation or any other type of wearable technology. However, the measure used in the study (IPAQ) is frequently used in both clinical and epidemiological observational studies. Finally, our study was underpowered for some of the stratified analyses conducted and there is a possibility of type I error given the number of covariates examined with QOL and AET-related symptoms. However, it should be noted that we detrmined covariates for the models a priori and did not use bivariate association p-values to determine covariates for the multiple regression models, thereby reducing some of the issues that type I errors may cause in model specification.
PA may a offer low-cost, practical approach to positively impact dimensions of overall quality of life and some AET-related symptoms. Future studies are needed that examine how PA may impact symptoms over time and other factors such as treatment adherence.
Acknowledgements:
The authors are grateful to the study participants who provided invaluable data by participating in this study. We also appreciate technical assistance from Mr. Matthew Wells, M.S.
Funding Information: This research was funded by the National Institutes of Health R01CA154848 and Bank of America (Sheppard). It was also supported in part by the NCI 2T32CA093423 (Sutton), NIH-NCI Cancer Center Support Grant P30 CA016059 and the TSA award No. UL1TR002649 from the National Center for Advancing Translational Sciences. Its contents are solely the responsibility of the authors and do not necessarily represent official views of the National Center for Advancing Translational Sciences or the National Institutes of Health.
Footnotes
Conflict of Interest: The authors declare that they have no conflict of interest.
References
- 1.Torre LA, Bray F, Siegel RL, et al. : Global cancer statistics, 2012. CA Cancer J Clin 65:87–108, 2015 [DOI] [PubMed] [Google Scholar]
- 2.Early Breast Cancer Trialists’ Collaborative Group E: Effects of chemotherapy and hormonal therapy for early breast cancer on recurrence and 15-year survival: an overview of the randomised trials. Lancet (London, England) 365:1687–1717, 2005 [DOI] [PubMed] [Google Scholar]
- 3.Society AC: Breast Cancer Facts & Figures 2017–2018 Atlanta, American Cancer Society, Inc. 2017 [Google Scholar]
- 4.Amir E, Seruga B, Niraula S, et al. : Toxicity of adjuvant endocrine therapy in postmenopausal breast cancer patients: a systematic review and meta-analysis. J Natl Cancer Inst 103:1299–309, 2011 [DOI] [PubMed] [Google Scholar]
- 5.Khosrow-Khavar F, Filion KB, Al-Qurashi S, et al. : Cardiotoxicity of aromatase inhibitors and tamoxifen in postmenopausal women with breast cancer: a systematic review and meta-analysis of randomized controlled trials. Ann Oncol 28:487–496, 2017 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6.Harrington CB, Hansen JA, Moskowitz M, et al. : It’s not over when it’s over: long-term symptoms in cancer survivors--a systematic review. Int J Psychiatry Med 40:163–81, 2010 [DOI] [PubMed] [Google Scholar]
- 7.Kim S, Ko YH, Song Y, et al. : Development of an exercise adherence program for breast cancer survivors with cancer-related fatigue-an intervention mapping approach. Support Care Cancer, 2019 [DOI] [PubMed] [Google Scholar]
- 8.Arem H, Sorkin M, Cartmel B, et al. : Exercise adherence in a randomized trial of exercise on aromatase inhibitor arthralgias in breast cancer survivors: the Hormones and Physical Exercise (HOPE) study. J Cancer Surviv 10:654–62, 2016 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Christensen JF, Simonsen C, Hojman P: Exercise Training in Cancer Control and Treatment. Compr Physiol 9:165–205, 2018 [DOI] [PubMed] [Google Scholar]
- 10.Park SH, Tish Knobf M, Jeon S: Endocrine Therapy-Related Symptoms and Quality of Life in Female Cancer Survivors in the Yale Fitness Intervention Trial. J Nurs Scholarsh 51:317–325, 2019 [DOI] [PubMed] [Google Scholar]
- 11.Baglia ML, Lin IH, Cartmel B, et al. : Endocrine-related quality of life in a randomized trial of exercise on aromatase inhibitor-induced arthralgias in breast cancer survivors. Cancer, 2019 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Kushi LH, Doyle C, McCullough M, et al. : American Cancer Society Guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA: a cancer journal for clinicians 62:30–67, 2012 [DOI] [PubMed] [Google Scholar]
- 13.Rock C, Doyle C, Demark-Wahnefried W, et al. : Nutrition and physical activity guidelines for cancer survivors. CA: a cancer journal for clinicians 62:275, 2012 [DOI] [PubMed] [Google Scholar]
- 14.McTiernan A, Kooperberg C, White E, et al. : Recreational physical activity and the risk of breast cancer in postmenopausal women: the Women’s Health Initiative Cohort Study. JAMA 290:1331, 2003 [DOI] [PubMed] [Google Scholar]
- 15.Tarasenko Y, Linder D, Miller E: Muscle-strengthening and aerobic activities and mortality among 3+ year cancer survivors in the U.S. An International Journal of Studies of Cancer in Human Populations 29:475–484, 2018 [DOI] [PubMed] [Google Scholar]
- 16.Duijts SFA, van Beurden M, Oldenburg HSA, et al. : Efficacy of cognitive behavioral therapy and physical exercise in alleviating treatment-induced menopausal symptoms in patients with breast cancer: results of a randomized, controlled, multicenter trial. Journal of clinical oncology : official journal of the American Society of Clinical Oncology 30:4124, 2012 [DOI] [PubMed] [Google Scholar]
- 17.Penttinen H, Utriainen M, Kellokumpu-Lehtinen PL, et al. : Effectiveness of a 12-month Exercise Intervention on Physical Activity and Quality of Life of Breast Cancer Survivors; Five-year Results of the BREX-study. In Vivo 33:881–888, 2019 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18.Pekmezi D, Ainsworth C, Desmond R, et al. : Physical Activity Maintenance Following Home-Based, Individually Tailored Print Interventions for African American Women. Health Promot Pract:1524839918798819, 2018 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19.Lee K, Tripathy D, Demark-Wahnefried W, et al. : Effect of Aerobic and Resistance Exercise Intervention on Cardiovascular Disease Risk in Women With Early-Stage Breast Cancer: A Randomized Clinical Trial. JAMA Oncol, 2019 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Phillips SM, McAuley E: Social cognitive influences on physical activity participation in long-term breast cancer survivors. Psychooncology 22:783–91, 2013 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Brunet J, Taran S, Burke S, et al. : A qualitative exploration of barriers and motivators to physical activity participation in women treated for breast cancer. Disabil Rehabil 35:2038–45, 2013 [DOI] [PubMed] [Google Scholar]
- 22.Sheppard VB, Hurtado-de-Mendoza A, Zheng YL, et al. : Biospecimen donation among black and white breast cancer survivors: opportunities to promote precision medicine. J Cancer Surviv 12:74–81, 2018 [DOI] [PubMed] [Google Scholar]
- 23.Harris PA, Taylor R, Thielke R, et al. : Research electronic data capture (REDCap)--a metadata-driven methodology and workflow process for providing translational research informatics support. Journal of Biomedical Informatics 42:377–381, 2009 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Craig CL, Marshall AL, Sjostrom M, et al. : International physical activity questionnaire: 12-country reliability and validity. Medicine and science in sports and exercise 35:1381–1395, 2003 [DOI] [PubMed] [Google Scholar]
- 25.Lee PH, Macfarlane DJ, Lam TH, et al. : Validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF): a systematic review. Int J Behav Nutr Phys Act 8:115, 2011 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26.Cella DF, Tulsky DS, Gray G, et al. : The Functional Assessment of Cancer Therapy scale: development and validation of the general measure. Journal of clinical oncology : official journal of the American Society of Clinical Oncology 11:570–579, 1993 [DOI] [PubMed] [Google Scholar]
- 27.Sherbourne CD, Stewart AL: The MOS social support survey. Social science & medicine (1982) 32:705–714, 1991 [DOI] [PubMed] [Google Scholar]
- 28.Belsley DA: Regression diagnostics : identifying influential data and sources of collinearity. New York, New York: : Wiley, 1980 [Google Scholar]
- 29.Mason C, Alfano CM, Smith AW, et al. : Long-term physical activity trends in breast cancer survivors. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology 22:1153–1161, 2013 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 30.Zhao G, Li C, Okoro CA, et al. : Trends in modifiable lifestyle-related risk factors following diagnosis in breast cancer survivors. J Cancer Surviv 7:563–9, 2013 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 31.Bassett DR Jr., Cureton AL, Ainsworth BE: Measurement of daily walking distance-questionnaire versus pedometer. Med Sci Sports Exerc 32:1018–23, 2000 [DOI] [PubMed] [Google Scholar]
- 32.Strycker LA, Duncan SC, Chaumeton NR, et al. : Reliability of pedometer data in samples of youth and older women. Int J Behav Nutr Phys Act 4:4, 2007 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 33.Spector D, Deal AM, Amos KD, et al. : A pilot study of a home-based motivational exercise program for African American breast cancer survivors: clinical and quality-of-life outcomes. Integr Cancer Ther 13:121–32, 2014 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 34.Coughlin SS, Yoo W, Whitehead MS, et al. : Advancing breast cancer survivorship among African-American women. Breast Cancer Res Treat 153:253–61, 2015 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 35.Stolley MR, Sharp LK, Wells AM, et al. : Health behaviors and breast cancer: experiences of urban African American women. Health education & behavior : the official publication of the Society for Public Health Education 33:604–624, 2006 [DOI] [PubMed] [Google Scholar]
- 36.Spector D, Battaglini C, Groff D: Perceived exercise barriers and facilitators among ethnically diverse breast cancer survivors. Oncol Nurs Forum 40:472–80, 2013 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 37.Oyekanmi G, Paxton RJ: Barriers to physical activity among African American breast cancer survivors. Psychooncology 23:1314–7, 2014 [DOI] [PMC free article] [PubMed] [Google Scholar]