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Keywords:

  • breast neoplasm;
  • African American;
  • disparities;
  • Hispanic;
  • obesity;
  • quality of life;
  • cancer survivors

Abstract

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

BACKGROUND:

Health-related quality of life (HRQOL), body mass index (BMI), and physical activity (PA) levels have all been associated with prognosis following breast cancer and may explain partially the higher mortality for breast cancer in certain racial/ethnic subgroups. In this study, associations between PA, BMI, and HRQOL by race were examined in a sample of breast cancer survivors.

METHODS:

Measures of PA, BMI, and HRQOL as well as demographic and medical characteristics of women (N = 3013, 13% nonwhite) who participated in the Women's Healthy Eating and Living Study were assessed at baseline. Analysis of covariance was used to examine the relationship between PA and obesity with HRQOL outcomes. Statistical tests were 2-sided.

RESULTS:

African American women were less likely to meet guidelines for PA and more likely to be obese than women from other ethnic groups (P < .05). In adjusted models, women who met guidelines for PA reported significantly higher physical health composite (point differences ranged from 10.5 to 21.2 points, all P < .05) and vitality (point differences ranged from 9.9 to 16.5 points, all P < .05) scores than those who did not, regardless of race/ethnicity. Associations between obesity and HRQOL were mixed with fewer associations for Asian American and African American women and stronger associations for whites.

CONCLUSIONS:

Breast cancer survivors from racially and ethnically diverse populations have lower levels of PA and higher rates of obesity that are generally associated with poorer HRQOL. Culturally sensitive PA and weight loss interventions may improve these lifestyle characteristics and result in improved HRQOL. Cancer 2012. © 2012 American Cancer Society.

Prospective studies have shown that physical inactivity, obesity, and poor physical health are associated with poor breast cancer prognosis.1-6 In the Women's Healthy Eating and Living (WHEL) Study,7 meeting guidelines for physical activity (PA) reduced the risk for all-cause mortality,5 whereas poorer physical health increased the risk for recurrence and all-cause mortality.6 Literature reviews have shown consistently that obesity is associated with increased risk for mortality in breast cancer survivors8, 9 and may be associated with poor health-related quality of life (HRQOL). Similarly, minority women often report poor HRQOL10, 11 and are predisposed to poor breast cancer prognosis.1, 12, 13 It could be that poor adherence to guidelines for weight control and PA may, in part, explain the poor outcomes experienced by minority women.

National samples estimate that only 37% of breast cancer survivors are meeting current guidelines for PA,14 and 22% are obese.15 In addition, survivors have a 2-fold increased risk for functional limitations when compared to age-matched peers.16 Participating in regular PA and maintaining a healthy weight is associated with a number of benefits throughout the cancer continuum.17 Meta-analyses have indicated that PA interventions result in improvements in cancer-related symptoms, physical function, mood, and body mass index (BMI).18, 19

A number of studies have examined the relationship between health behaviors and HRQOL; however, few studies have examined these associations separately among Asian American, African American, and Hispanic breast cancer survivors. Racial/ethnic differences that may arise in the correlates of PA and obesity may have implications for supportive care centers that treat diverse populations and interventions designed to improve HRQOL among breast cancer survivors. Therefore, we examined rates of PA and obesity and determined the association between these factors and HRQOL in a diverse group of breast cancer survivors.

MATERIALS AND METHODS

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

Study Population

Data for the current study were collected as part of the WHEL Study (Clinicaltrials.gov identifier: NCT00003787), which recruited breast cancer survivors between 1995 and 2000 from clinical sites in California, Arizona, Oregon, and Texas. The institutional review board at each site approved the WHEL Study protocol. Eligible patients had been diagnosed with stage I-IIIA breast cancer within the past 4 years, were 18 to 70 years old at diagnosis, had completed treatment with no evidence of new or recurrent disease, and had no other cancers within the past 10 years. Additional WHEL Study inclusion and exclusion criteria have been reported previously.7 WHEL Study participants who self-reported their ethnicity as Asian American, African American, Hispanic, or white were included in the current analysis. The WHEL Study protocol and public use data are available from the WHEL Study public access Web site (http://libraries.ucsd.edu/ssds/whel.html).

Measures

In the WHEL Study, HRQOL was assessed using the SF 36-Item Health Survey.20 The survey assesses levels of health and includes questions pertaining to physical and mental well-being. The reliability and validity of this instrument have been established in various cancer survivor populations.21, 22 The survey consists of 4 subscales each for mental (ie, mental health, vitality, role limitations due to emotional problems, and social functioning) and physical (ie, physical functioning, general health perceptions, bodily pain, and role limitations due to physical health problems) health.20 Although each score represents an individual subscale, the scores can be consolidated to generate an overall HRQOL summary score or composite scores for mental and physical health. Subscale scores range from 0 to 100, with higher scores indicating better health.

Physical Activity

PA was assessed with a self-administered instrument designed for the Women's Health Initiative.23 PA was calculated separately for light (metabolic equivalent tasks [MET] level < 3.0), moderate (MET level 3.0-5.9), and vigorous (MET level ≥ 6.0) activities. A variable was also created for moderate-to-vigorous PA (MET level ≥ 3.0), which was then used to create a dichotomous variable (“meeting PA guidelines”) based on a cutoff of 10.0 MET hours/week, which equaled approximately 150 minutes/week of moderate-paced walking or the equivalent of other exercise durations and/or intensities. The cutoff used here was consistent with the current recommendations of the Centers for Disease Control and Prevention for PA24 and has been validated in previous studies.5, 25

Body Mass Index

BMI was assessed for the WHEL Study by a qualified professional at baseline using the standard calculation of weight in kilograms over height in meters squared (kg/m2). For the purposes of this study, we used ethnic-specific obesity cut points. Obesity for Asian Americans was established as BMI ≥ 25.0 kg/m2; this estimate is based on evidence that Asian Americans experience comorbid conditions at lower BMIs than women of other ethnic groups.26-28 Obesity for African Americans, Hispanics, and whites was established as BMI ≥ 30 kg/m2.

Medical and Demographic Characteristics

Clinical data were obtained from the patients' medical records. We used the following study variables: time from diagnosis, stage at diagnosis, and age at study entry. We also summed the number of chronic conditions (eg, cardiovascular disease, blood sugar/diabetes, digestive disorders, arthritis, and osteoporosis) self-reported at baseline.

Statistical Analyses

Descriptive statistics of HRQOL and medical and lifestyle factors were calculated for WHEL Study participants in each racial group. Racial/ethnic differences were examined using a chi-square test of independence for categorical variables and a nonparametric Kruskal-Wallis test for non-normal continuous variables. Analysis of covariance adjusted for medical and demographic characteristics was then used to determine whether mean differences in HRQOL exist between PA and obesity status for each race/ethnicity. Next, adjusted analyses of covariance stratified by race/ethnicity were computed to determine associations specific to race/ethnicity. Models for Asian Americans, African Americans, and Hispanics were adjusted for PA or BMI, number of chronic conditions, and age at study entry. Models for whites were adjusted for PA or BMI, number of chronic conditions, time since diagnosis, age at study entry, and disease stage at diagnosis. All reported P values were 2-sided, and a value of P ≤ 0.05 was considered statistically significant.

RESULTS

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

Medical and Demographic Characteristics

WHEL Study participants were primarily white (87%), but the sample included an adequate number of Asian American (n = 96, 3%), African American (n = 118, 4%), and Hispanic (n = 165, 6%) survivors (Table 1). Time since diagnosis, disease stage at diagnosis, and number of chronic conditions did not differ by race (all P > .05). However, African American and Hispanic participants were younger at study entry, younger at diagnosis, and more likely to be premenopausal than Asian Americans and whites (P < .05). Hispanics had the lowest education levels and Asian Americans had the highest education levels (P < .01).

Table 1. Descriptive Characteristics by Race for Women Previously Treated for Breast Cancera
VariableAsian American n = 96African American n = 118Hispanic n = 165White n = 2634P
  • a

    Continuous P values are based on a nonparametric Kruskal-Wallis test, whereas categorical P values are based on a chi-square test for independence. Number of chronic conditions was computed by adding the number of chronic conditions that participants reported at study entry. These conditions included diabetes, cardiovascular disease, digestive disorders, arthritis, and osteoporosis.

Median age at study entry, y (25%, 75%)52 (47, 58)49 (43, 54)50 (44, 57)52 (47, 59)<.001
Median time since diagnosis, y (25%, 75%)2 (1, 3)2 (1, 3)2 (1, 2)2 (1, 3).216
Median age at diagnosis, y (25%, 75%)50 (45, 56)47 (42, 52)48 (42, 55)51 (45, 57)<.001
Number of chronic conditions (25%, 75%)0 (0, 1)0 (0, 1)0 (0, 1)0 (0, 1).977
Stage at diagnosis, n (%)    .055
 I41 (43)38 (32)51 (31)1034 (39) 
 II54 (56)75 (64)101 (61)1469 (56) 
 IIIA1 (1)5 (4)13 (8)131 (5) 
Postmenopausal, n (%)87 (91)95 (81)139 (85)2345 (89).020
Education, n (%)    <.001
 High school or less9 (9)20 (17)55 (33)373 (14) 
 Some college16 (17)39 (33)59 (36)819 (31) 
 College graduate or more71 (74)59 (50)51 (31)1442 (55) 

Racial/Ethnic Differences in HRQOL, PA, Obesity, and Health Behavior Status

Racial/ethnic differences in the physical health and one of its subscales (ie, physical function) were observed (Table 2; P < .05). Asian American and white survivors reported physical health scores significantly higher than those of African American and Hispanic survivors, and this difference appeared to result mainly from lower physical function scores in African American and Hispanic survivors (P < .01). Asian American survivors also reported the lowest BMIs of all the racial/ethnic groups (P < .01), whereas African American survivors had the highest BMIs (P < .01). African American (45%) and Asian American (42%) survivors were obese in greater proportions than white (25%) and Hispanic (32%) survivors (P < .05). White (52%) and Asian American (48%) survivors were more active and met the guidelines for PA in higher proportions than Hispanic (39%) and African American (32%) survivors (all P < .01).

Table 2. Health-Related Quality of Life (HRQOL), Physical Activity, and Body Mass Index by Race/Ethnicity Among Breast Cancer Survivorsa
 Asian AmericanAfrican AmericanHispanicWhite 
 Median25%, 75%Median25%, 75%Median25%, 75%Median25%, 75%Pb
  • METMIN indicates metabolic equivalent min/wk; PA indicates physical activity.

  • a

    HRQOL numbers represent subscale scores (from 0-100) on the SF 36-Item Health Survey.

  • b

    P value based on a nonparametric Kruskal-Wallis test.

Overall HRQOL80.8(67, 89)78.8(61, 88)75.8(63, 88)79.8(66, 89).128
 Physical Health Composite81.3(70, 90)74.4(50, 90)77.4(54, 88)81.3(61, 91).013
  Physical function90.0(80, 100)85.0(65, 95)85.0(75, 95)90.0(80, 95).001
  Physical role functioning100.0(50, 100)75.0(50, 100)75.0(25, 100)100.0(50, 100).108
  Pain87.5(75, 88)87.5(56, 88)75.0(63, 100)87.5(63, 88).523
  General health72.5(60, 85)70.0(60, 80)70.0(55, 85)75.0(60, 85).061
 Mental Health Composite81.6(66, 91)80.8(65, 90)77.7(62, 88)81.3(68, 89).341
  Vitality65.0(50, 75)60.0(45, 75)60.0(40, 80)60.0(45, 75).163
  Emotional role functioning100.0(67, 100)100.0(67, 100)100.0(67, 100)100.0(67, 100).377
  Social function100.0(75, 100)100.0(75, 700)100.0(75, 100)100.0(75, 100).270
  Mental health80.0(72, 88)82.0(68, 88)76.0(64, 88)80.0(68, 88).514
Body mass index24.4(22, 28)29.3(26, 34)26.9(24, 31)25.7(23, 30)<.001
METMIN582.5(225, 1200)225.0(30, 900)375.0(38, 983)607.5(225, 1320)<.001

Adjusted Associations Between PA, Obesity, and HRQOL

Survivors who met the guidelines for PA reported significantly higher physical health (point differences ranged from 10.5 to 21.2 points, all P < .05) and vitality scores (point differences ranged from 9.9 to 16.5 points, all P < .05) than those who did not meet the guidelines (Table 3). African American, Hispanic, and white survivors who met the guidelines for PA reported significantly higher overall HRQOL (point differences ranged from 5.9 to 9.6 points, all P < .05) and general health (point differences ranged from 7.2 to 9.9 points, all P < .05) scores than those who did not meet PA guidelines. Only Hispanic and white survivors who met the guidelines for PA also reported significantly higher physical function (point differences ranged from 7.1 to 11.0 points, all P < .05) and mental health (point differences ranged from 3.5 to 6.6 points, all P < .05) scores than those who did not meet the guidelines (Fig. 1A,B).

Table 3. Mean Differences in Quality of Life Subscales by Physical Activity Status and Race/Ethnicitya
 Asian n = 96African American n = 118Hispanic n = 165White n = 2634
 Not meeting M (SE)Meeting M (SE)PbNot meeting M (SE)Meeting M (SE)PbNot meeting M (SE)Meeting M (SE)PbNot meeting M (SE)Meeting M (SE)Pc
  • a

    HRQOL indicates health-related quality of life; M, mean; SE, standard error. HRQOL numbers represent subscale scores (from 0-100) on the SF 36-Item Health Survey. Participants classified as meeting requirements reported ≥10 metabolic equivalents task h/wk; this estimate is equivalent to participating in 150 min of moderate to vigorous physical activity/wk. The physical health subscale represents the mean score for subscales of physical function, role-physical functioning, pain, and general health. Similarly, the mental health subscale represents the mean score for subscales of vitality, emotional role functioning, social function, and mental health. Significant p-values were bolded to enhance visibility.

  • b

    Estimates were adjusted body mass index, number of chronic conditions, and age at study entry.

  • c

    Estimates were adjusted body mass index, number of chronic conditions, time from diagnosis, age at study entry, stage of diagnosis, and education.

Overall HRQOL76.7 (2.3)80.5 (2.4).26469.2 (2.3)78.8 (3.2).01969.4 (1.9)76.6 (2.4).02071.7 (0.7)76.6 (0.7).001
Physical health65.1 (4.4)81.5 (4.7).01757.9 (3.5)79.1 (5.2).00165.1 (2.5)76.8 (3.1).00466.9 (0.9)77.4 (1.0).001
Physical function86.1 (2.3)90.4 (2.4).21674.7 (2.6)81.2 (3.6).15675.7 (1.9)76.6 (2.4).01379.6 (0.7)86.7 (0.7).001
Role-physical73.2 (5.6)83.8 (5.8).21160.2 (4.8)78.9 (6.6).02760.4 (4.3)71.5 (5.3).11265.5 (1.6)71.5 (1.6).001
Pain77.3 (3.3)80.3 (3.4).54670.9 (3.4)76.0 (4.6).38571.9 (2.6)75.4 (3.2).40471.1 (1.0)74.7 (1.0).001
General health70.5 (2.5)73.5 (2.6).41166.2 (1.7)74.8 (2.4).00563.9 (2.1)73.8 (2.6).00464.7 (0.8)74.6 (0.8).001
Mental health76.7 (2.5)79.1 (2.6).52470.5 (2.6)79.9 (3.5).03970.0 (2.1)76.5 (2.5).05172.5 (0.7)78.3 (0.7).001
Vitality59.3 (5.6)69.2 (2.7).01354.2 (2.4)64.2 (3.3).01849.6 (2.4)66.1 (2.1).00152.4 (0.9)63.1 (0.9).001
Role-emotional85.1 (4.9)83.4 (5.1).81870.3 (4.9)89.0 (6.6).02877.3 (3.9)74.0 (4.2).70279.0 (1.4)83.8 (1.4).001
Social function85.1 (3.1)85.9 (3.1).85381.7 (2.9)89.3 (4.0).13481.8 (2.4)87.1 (2.8).15183.4 (0.9)87.9 (0.9).001
Mental health77.2 (2.2)77.9 (2.3).82475.7 (2.3)77.1 (3.2).72171.2 (1.9)77.8 (2.3).03174.9 (0.6)78.4 (0.6).001
thumbnail image

Figure 1. Associations between health behavior status and quality of life component scores by race/ethnicity. This graphic depiction included: Physical (1A) and mental (1B) health component scores by meeting and not meeting guidelines for physical activity (PA); and physical (1C) and mental (1D) health component scores by obesity status. Bars represent unadjusted means and 95% confidence intervals.

Download figure to PowerPoint

Nonobese African American, Hispanic, and white survivors reported significantly higher physical function scores (point differences ranged from 8.9 to 10.0 points, all P < .05) than those who were obese (Table 4). Nonobese white survivors reported significantly higher physical role functioning, physical health, emotional role functioning, vitality, pain, and overall HRQOL (point differences ranged from 5.9 to 8.9 points, all P < .05) scores than those who were obese (Fig. 1C,D).

Table 4. Mean Differences in Quality of Life Subscales by Obesity Status and Race/Ethnicitya
 Asian American n = 96African American n = 118Hispanic n = 165White n = 2634
 Nonobese M (SE)Obese M (SE)PbNonobese M (SE)Obese M (SE)PbNonobese M (SE)Obese M (SE)PbNonobese M (SE)Obese M (SE)Pc
  • a

    HRQOL indicates health-related quality of life; M, mean; SE, standard error. HRQOL numbers represent subscale scores (from 0-100) on the SF 36-Item Health Survey. Body mass index scores ≥30 were used to classify African American, Hispanic, and white women as obese, whereas scores of ≥25 were used for Asian Americans. The obesity cutoff point for Asian Americans is based on recent recommendations from the World Health Organization.22-24 The physical health subscale represents the mean score for subscales of physical function, role-physical functioning, pain, and general health. Similarly, the mental health subscale represents the mean score for subscales of vitality, emotional role functioning, social function, and mental health. Significant p-values were bolded to enhance visibility.

  • b

    Estimates were adjusted physical activity, number of chronic conditions, and age at study entry.

  • c

    Estimates were adjusted physical activity, number of chronic conditions, time from diagnosis, age at study entry, stage of diagnosis, and education.

Overall HRQOL79.5 (2.0)77.2 (2.5).48175.1 (2.7)69.7 (2.9).17873.8 (1.9)69.1 (2.7).16276.2 (0.6)70.3 (0.8).001
Physical health79.3 (3.2)73.4 (4.0).26271.4 (3.3)67.6 (3.7).45274.9 (2.1)65.6 (3.0).01375.7 (0.7)68.4 (1.0).001
Physical function87.7 (2.0)89.1 (2.6).67381.2 (3.0)72.2 (3.2).04485.1 (1.9)75.0 (2.9).00485.3 (0.7)76.4 (0.9).001
Role-physical82.6 (4.9)71.9 (6.2).18870.2 (5.5)62.8 (5.9).37068.6 (4.1)57.1 (6.1).12770.8 (1.5)61.9 (2.0).001
Pain80.9 (2.9)75.3 (3.7).24476.6 (3.8)68.3 (4.1).14176.5 (2.5)66.6 (3.7).03074.6 (0.9)68.2 (1.2).001
General health72.5 (2.2)71.2 (2.8).71170.3 (2.0)67.8 (2.1).39669.8 (2.1)63.8 (3.0).11272.4 (0.7)67.5 (1.0).001
Mental health78.0 (2.2)77.6 (2.8).89575.7 (3.0)71.8 (3.2).37272.7 (2.2)54.4 (3.3).97276.7 (0.7)72.2 (0.9).001
Vitality63.6 (2.2)65.0 (2.7).68659.5 (2.8)55.7 (3.0).36557.2 (2.2)54.4 (3.3).48959.7 (0.8)53.2 (1.1).001
Role-emotional86.4 (4.4)80.9 (5.5).45076.0 (5.5)77.9 (5.9).81974.6 (3.6)80.0 (5.4).41583.2 (1.3)76.3 (1.7).001
Social function85.7 (2.7)85.2 (3.4).91887.1 (3.3)81.2 (3.5).23685.2 (2.2)81.2 (3.3).32186.4 (0.8)84.0 (1.1).020
Mental health76.6 (1.9)79.1 (2.4).42580.0 (2.5)71.9 (2.6).03073.6 (1.8)74.5 (2.6).77177.3 (0.6)75.3 (0.8).010

DISCUSSION

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

In this study, we examined the associations between PA, obesity status, and HRQOL in a large cohort of breast cancer survivors that included minorities. We found that more Asian American and white survivors met the guidelines for PA than African American and Hispanic survivors. Moreover, African American survivors were obese in greater proportions than white, Asian American, and Hispanic survivors. Notably, meeting current guidelines for PA was associated with significantly higher physical health and vitality scores for survivors, regardless of race. Our findings also suggest that nonobese African American, Hispanic, and white survivors have higher physical function than their obese counterparts. These data not only support the findings of previous studies that confirmed the HRQOL benefits associated with PA, but they also provide more support for associations between obesity and functional decline among cancer survivors.

Consistent with previous research,29-31 the African American and Hispanic survivors in this study were heavier and less active than their white and Asian American counterparts. Approximately one-third of African American and Hispanic survivors met current guidelines for PA, and African American survivors had the highest rates of obesity. The lower levels of physical function and PA among African American and Hispanic survivors are public health challenges, given evidence that PA is associated with improvements in recurrence-free and overall survival.2, 5, 32, 33 Taking into consideration that African American and Hispanic survivors have the poorest breast cancer–specific outcomes, there is a need for culturally sensitive interventions that provide skills that will enable minority survivors to initiate and maintain a regimen of PA at recommended levels.

Meeting current guidelines for PA was associated with higher physical health composite scores for survivors, regardless of race. Our findings are supported by cross-sectional studies, systematic reviews, and meta-analyses that have reported positive associations between PA and physical function.18, 30, 34-37 These associations are important in light of recent evidence suggesting that poor physical function may elevate the risk for additional breast cancer events and premature death.6 Breast cancer survivors who are less likely to be PA, such as African American and Hispanic survivors, may lower their risk of recurrence by participating in recommended amounts of PA and improving their physical health.

The association between PA and the mental health composite subscale observed among African American, Hispanic, and white survivors was not expected, because the results of previous studies investigating these relationships have been mixed.34, 38 In our study, meeting guidelines for PA contributed most to vitality (ie, fatigue) scores, which is consistent with a recent review.18 PA may improve mental health by distracting survivors from daily stressors, increasing self-confidence and self-esteem, promoting social interactions, and improving body image.25 More research is needed to understand why the mental health benefits appear to differ between racial/ethnic groups.

Asian American women did not appear to experience similar physical or mental health benefits. It could be that many of these women were participating in lower intensity activities such as yoga, but did not reach the 600 MET-minutes threshold we used in this study. Recent studies conducted among cancer survivors have indicated that yoga is associated with improvements in HRQOL.39, 40 According to the PA Compendium,41 yoga is associated with 2.5 MET, and therefore if a person is active 30 minutes/day for 5 days/week, this equates to 375 MET-minutes of PA. Alternatively, reporting biases may be a limitation. A recent study suggested that Asians prefer to report physical ailments in place of mental health problems, which are stigmatized as a spiritual or moral weakness.42 More research is needed to determine the specific physical activities that Asian American cancer survivors prefer and whether yoga and other lower intensity exercise derive similar HRQOL benefits.

Contrary to our expectations, few statistically significant mean differences in HRQOL outcomes by obesity were observed. Obesity appeared to have the greatest impact on physical health, but only in Hispanic and white survivors, which is depicted in our figures. We believe few associations were detected between obesity and HRQOL among African Americans because many (>80%) were overweight or obese. In addition, it could be that cultural norms and acceptance of larger weights among African American survivors may have contributed to these differences. With respect to the overall associations, the results we observed here are consistent with some,43, 44 but not all, studies conducted in cancer survivors.30, 45 It may be that the associations between obesity and HRQOL outcomes were attenuated after controlling for important determinants such as the number of comorbid conditions and PA. We can only speculate that other protective factors, such as a healthy diet,30 prevented mental decline, which is likely in view of the diet reported by Asian American survivors in the WHEL Study.46

The results from this study provide important and unique information about a diverse group of breast cancer survivors and the impact of race/ethnicity on the relationship between health status and HRQOL. There are, however, several limitations of this study that should be noted. The sample of breast cancer survivors was relatively healthy at baseline and well-educated, so the results may not generalize to other populations of breast cancer survivors. In addition, PA was assessed using a self-reported measure; therefore, recall and reporting biases might have existed. It should also be noted we were underpowered to test for interactions due to large differences between the sample sizes of whites versus that of our minority survivors. Nonetheless, this is one of the first studies to examine these associations among Asian American, African American, and Hispanic breast cancer survivors.

Overall, the results from this study support previous research on the relationship between PA, obesity, and HRQOL and provide new evidence of the potential differences that may exist between races/ethnicities. These data suggest a potentially greater risk of poor HRQOL among women who are not meeting guidelines for PA and an even greater need for research that examined the consequences of obesity in breast cancer survivors. This information is useful in understanding the needs of diverse populations and in planning interventions designed to improve their health and well-being. Promoting recommended amounts of PA and weight control are particularly important interventions for minority breast cancer survivors, because they are often underrepresented in clinical trials that promote health behaviors, despite minorities' elevated risk for recurrence and premature death.

Acknowledgements

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

We thank the Women's Healthy Eating and Living Study Group, who were involved in patient recruitment and data collection, and the staff and participants of the Women's Healthy Eating and Living Study.

FUNDING SOURCES

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES

This research was supported in part by National Cancer Institute grants K01CA158000 (to R.J.P.) and P60 MD000503 (to J.P.P.) and by the National Institutes of Health through the University of Texas MD Anderson Cancer Center Support Grant (CA016672).

CONFLICT OF INTEREST DISCLOSURE

The authors made no disclosure.

REFERENCES

  1. Top of page
  2. Abstract
  3. MATERIALS AND METHODS
  4. RESULTS
  5. DISCUSSION
  6. Acknowledgements
  7. FUNDING SOURCES
  8. REFERENCES
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