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© 2002 American Society for Clinical Oncology Dietary Change After Breast Cancer: Extent, Predictors, and Relation With Psychological DistressByFrom the Population Health Research Unit, Department of Social and Preventive Medicine, Université Laval, Centre des Maladies du Sein Deschênes-Fabia, Saint-Sacrement Hospital, and Department of Surgery, Université Laval, Québec, Québec, Canada. Address reprint requests to Elizabeth Maunsell, PhD, Unité de Recherche en Santé des Populations, CHA-Pavillon Saint-Sacrement, 1050 Chemin Ste-Foy, Québec, QC, Canada G1S 4L8; email: elizabeth.maunsell{at}uresp.ulaval.ca
PURPOSE: Some women may try to cope with breast cancer by making lifestyle modifications, possibly in the hope of improving disease outcome. We assessed extent, predictors, and effect on psychological distress of dietary changes in the year after diagnosis among 250 women with newly diagnosed, nonmetastatic breast cancer. PATIENTS AND METHODS: Data came from medical records, and from interviews 3 days and 12 months after initial treatment. RESULTS: At 12 months, 41% (n = 103) reported dietary changes at some time since diagnosis, with decreases in meat (77%) and increases in fruit and vegetable intake (72%) being the most frequent. Women reporting changes were more likely to be younger, to have positive nodes, to be receiving adjuvant therapy, and to be more distressed initially. The mean 0 to 12 month decrease in psychological distress was greater in women who reported changes (9 points) than those who did not (4.7 points) (P = .03), although regression toward the mean cannot be excluded. CONCLUSION: A sizable proportion of women made dietary changes on their own initiative. Most changes reported were generally consistent with current scientific hypotheses about dietary changes that might favorably affect prognosis. The profile of women reporting changes suggests a group with more concerns about recurrence, who may have initiated dietary change to help cope with and gain a sense of control over the disease, and possibly to improve prognosis. Our results suggest that newly diagnosed women could be receptive to explicit attention to diet as part of psychosocial care. However, this interest in dietary change may not, as yet, have been maximally channeled into trying to improve the care and quality of life of women facing diagnosis, treatments, and fears about recurrence.
BREAST CANCER DIAGNOSIS is a stressor of considerable magnitude. One particular source of stress is worry that the disease will recur. Indeed, we have observed that at least half of newly diagnosed women worry at the time of surgical treatment about possible disease evolution.1,2 Similarly, others have reported that worry that the cancer will come back is the number one concern in the first year after diagnosis.3 These stressors—diagnosis, treatments, and concerns about prognosis—may in turn result in considerable psychological morbidity among newly diagnosed women.4-7 Anecdotal evidence, clinical observation, and research studies5,8,9 indicate that some newly diagnosed women initiate behavioral or lifestyle changes in the period after diagnosis and initial treatments. Changes reported include information seeking, initiation of or increased use of stress management techniques, physical activity, and dietary changes.8-11 It is not surprising that women focus on these types of behaviors. First, newly diagnosed patients may be given materials about coping with the illness. These often include information about adequate eating patterns to help maintain health and quality of life during cancer treatments.12-15 Second, such behaviors are consistent with current public health cancer prevention messages about the role of a healthy lifestyle in reducing the risk of cancer occurrence.12-14,16-18 Specifically in relation to diet, these messages indicate that excessive dietary fat intake and low consumption of fiber-rich foods could be associated with increased cancer risk.14,19-21 Not surprisingly, then, women may reason that if diet can affect occurrence of the disease, it might conceivably also affect its progression.16 Indeed, the hypothesis of a link between diet and disease recurrence is shared by the scientific community.22,23 Two major randomized trials, the Women’s Intervention Nutrition Study and the Women’s Healthy Eating and Living Study, are currently in progress to test the hypothesis that dietary change—either dietary fat reduction24,25 or adoption of a low-fat diet also high in fiber, vegetables, and fruit26—might improve the prognosis of women with nonmetastatic breast cancer. Thus, dietary change after breast cancer diagnosis may be a problem-focused coping strategy initiated not only to maintain health but also in the hope of reducing the likelihood of disease recurrence.5,6,27 Although anecdotal evidence supports the idea that dietary changes may be an important coping strategy used by women with breast cancer, no study has focused specifically on the description of dietary changes after a breast cancer diagnosis, or assessed personal, disease, or treatment characteristics that predict such changes among women likely to be representative of those facing nonmetastatic breast cancer. Thus, objectives of the present analyses were to (1) describe the nature and frequency of dietary change in the year after breast cancer diagnosis, (2) identify characteristics of women more likely to initiate such change, and (3) determine whether initiating such change is associated with psychological distress, an important component of quality of life.28
Data for these analyses came from participants in a randomized trial assessing effects on quality of life in the year after breast cancer diagnosis of a monthly telephone psychological distress screening program, with additional psychosocial help offered only to high-distress patients identified through screening.1 Trial participants and procedures have been described fully elsewhere.1 Briefly, a consecutive series of all newly diagnosed breast cancer patients with localized or regional stage disease first surgically treated at the Deschênes-Fabia Breast Disease Centre, Quebec City, between October 1990 and July 1992 who met study eligibility criteria were invited to participate. Eligible women were contacted by a research nurse during hospitalization for initial surgical treatment and informed of study objectives and procedures. Patients participated in three interviews, the first conducted immediately after obtaining consent, and the two others 3 and 12 months later. These interviews were highly structured and scripted. Questions were asked in the same way and order for all patients and generally had closed-ended responses. Data used in these analyses came from 250 women who completed all three study interviews. These women represent 89% of the consecutive series of 282 women initially eligible for the trial.
Baseline Interview
12-Month Interview With respect to diet, a general filter question—"During the past 12 months, have you made any changes to your diet?"—was first asked to determine whether women had initiated any dietary changes since diagnosis. If the woman said yes, the interviewer then asked about specific changes in different food types or dietary constituents. Specifically, items referring to changes in consumption of meat, fish, fruit and vegetables, legumes, dessert, alcohol, vitamins, dairy products, and cereals and bread were assessed in this order. Most of these items were chosen by the principal investigator (E.M.) to represent lay beliefs about changes that might be made when the desire is to have a healthier diet overall. Although they are not considered a food type per se, vitamins were included because of anecdotal reports and in-depth interviews from previous studies on our setting indicating that some women increase their intake of vitamin supplements even in the absence of clear-cut recommendations to do so. In everyday usage in French, the term vitamins refers implicitly to taking vitamins (ie, "vitamin supplements"). Otherwise we would have had to specify "foods rich in vitamins" to get at foods perceived to be good sources of vitamins. Also, the structuring of queries in terms of discrete food types (consumption of meat, fish, fruit and vegetables, and so forth) before the item on vitamins also contributed to framing the query as one about "taking vitamins." However, ultimately the interpretation of the term was left up to the study participant. As a result, it is possible that some patients included both vitamin sources in their response. Finally, to assess the direction of any changes reported, women were asked to say how they had changed, that is, whether consumption in a particular food type or dietary constituent had increased or decreased in the period since diagnosis. We also had to add the response options "introduced" and "eliminated" to accurately account for a few women’s reporting of changes they had made. Then, basing our judgments largely on current recommendations contained in dietary guidelines for cancer prevention as the basis for classification, each change was qualified a priori by the authors as positive or negative.13 On this basis, changes were considered positive if intake of fish, fruit and vegetables, and legumes was reported as increased (or introduced), and if intake of meat, desserts (which may contain large quantities of fat), and alcohol was reported as reduced (or eliminated). Changes in dairy products were qualified as positive if the woman reported consuming products with a lower milk-fat content. Changes in consumption of cereals and bread were rated as positive if the woman reported consuming ones with a higher fiber content. Only changes in vitamin intake could not be classified in this way. Very large doses of some vitamins or some combinations of vitamins as dietary supplements could potentially be harmful.13 Greater precision about the nature of the increase, data that were unavailable in this study, would have been necessary to judge whether reported increases could be classified as positive or negative.
Review of Medical Files
Statistical Analysis The previous analyses also served to identify potential confounding variables for the relation between dietary change and psychological distress. Spearman correlation coefficients were used to assess the extent to which possible confounding factors were associated with one another. The effect of possible confounders on the association of dietary change with psychological distress was examined first individually using stratified analysis, and then simultaneously with multiple linear regression. Both mean psychological distress scores and scores representing within-patient evolution in psychological distress levels from baseline to 12 months were used to assess the association between dietary change and psychological distress. In these analyses, the beta coefficient for dietary change which represents, respectively, the mean difference in distress scores or the mean difference in within-patient evolution in distress from 0 to 12 months, comparing women who reported dietary changes with those who did not, was chosen as the measure of association. A beta coefficient greater than 0 indicates, respectively, a higher score level at a given point in time or a greater decrease in psychological distress from 0 to 12 months, among women who reported dietary change compared with those who did not.
Among the 250 participants, 103 (41%) reported making dietary change in the 12 months since diagnosis (Table 1). Among women reporting change, meat intake was the most common change (77%), followed by fruit and vegetables (72%) and dessert (66%). A change in alcohol consumption was reported by only 19% of women (Table 1). Only a very small percentage of reported changes were classified as negative. The most frequent negative change was increased dessert intake, although overall the large majority of women still reported positive changes with respect to this food type (Table 1). Additional analysis among women who reported dietary changes showed that a mean of 4.4 (SD = 1.9) food types or dietary constituents were changed. Furthermore, those women reporting dietary changes defined as negative always also reported at least one change defined as positive.
On the basis of stratified analyses, women initiating dietary change were more likely to be younger (Table 2). Specifically, 50% of women aged less than 50 years initiated dietary change, compared with 42% and 16% among those aged 50 to 69 and  70 years, respectively. Women with regional stage disease at diagnosis who received adjuvant radiotherapy or chemotherapy were also more likely to report dietary change. Finally, higher initial psychological distress, a greater number of stressful events in the 5 years preceding diagnosis, and previous consultation with a mental health professional were all associated with initiating dietary change. When those variables found to be significant in the stratified analyses were included in a multivariate model, only younger age, higher psychological distress at baseline, and previous consultation with a mental health professional still significantly increased the likelihood of dietary change.
Spearman correlations among several variables identified as predictors of dietary change were statistically significant. However, only that between age and menopausal status (r = .82, P = .0001) presented a level of correlation considered high enough ( .75) to represent possible colinearity and thus merit exclusion of one variable (menopausal status) from further analyses of potential confounders.38 Compared with women reporting no dietary change, those reporting at least one such change during the year after breast cancer diagnosis were more distressed initially (mean PSI at baseline, 17.8 ± 1.0 and 24.4 ± 1.6, respectively; P = .0004) (Table 3). Given this difference, scores representing evolution in distress levels between 0 and 12 months appeared to be the most appropriate way to assess the relation between dietary changes and psychological distress. In analyses adjusted for possible confounders, women who reported initiating dietary changes had a significantly higher mean decrease in psychological distress (average, 9.0 points) in the year after diagnosis than those who did not make dietary changes (average, 4.7 points; P value testing difference between these decreases was .03) (Table 3). We found no dose-effect relationship in evolution scores when women making changes were subdivided into groups representing increasing numbers of changes. Consistent with the initially higher scores and greater decrease in scores among women who reported initiating dietary change, no significant difference in mean 12-month PSI scores was observed.
In this study among women with newly diagnosed nonmetastatic breast cancer, a sizable proportion of women, 41%, reported making changes in their dietary habits on their own initiative at some time during the 12 months after diagnosis. Furthermore, in the majority of cases, the dietary changes reported appeared to be generally consistent with current cancer prevention dietary guidelines and with current scientific hypotheses being tested in large-scale studies of dietary intervention and prognosis. Women reporting dietary changes were more likely to be younger, more distressed initially, have regional stage disease at diagnosis, have received adjuvant therapy, and have previously consulted a mental health professional. These women also experienced greater decreases in distress such that, 12 months later, their distress levels were comparable to those of women who had not made any dietary changes. This observation provides some, but not unequivocal, evidence to support the idea that women who reported initiating dietary change also experienced improved quality of life, when changes in psychological distress levels in the year after diagnosis were used as an indicator of quality of life. Our results on the nature of dietary changes made appear generally consistent with those from the very few previous studies that made some type of assessment of dietary changes after breast cancer.9,39 In a study by Grindel et al,39 the nature and frequency of dietary changes among women in the first 6 months of adjuvant chemotherapy were assessed by measuring food intake. In that small study (n = 19), 63% of women reported initiating changes in dietary patterns. These changes were described by women as "eating more nutritious foods, avoiding red meat and animal fat, eating more vegetables, and avoiding caffeine." More generally, a randomized trial assessing the effects of dietary advice on fat intake among women with newly diagnosed breast cancer demonstrated general interest in making dietary changes.40 Women randomized to both the intervention and control groups significantly decreased their fat intake. In another study of 78 women questioned 1 month to 5 years after breast cancer diagnosis, dietary change was the most common health-related behavioral change, reported by 49% of women.9 No studies have assessed factors identifying women likely to initiate dietary change, although our results are consistent with those of Lee et al,10 who assessed recourse to alternative therapies after breast cancer. Women reporting diet change in this context were younger, exercised, attended a support group, had later stage at diagnosis, and had an annual income higher than $20,000. In the vast majority of cases, the type and direction of dietary changes reported by women in this study were consistent with current best scientific hypotheses about dietary changes that might positively affect prognosis after nonmetastatic breast cancer.13,22,24-26 Furthermore, in most cases, the type of changes reported as undertaken, if maintained, would likely do no harm and could possibly even be beneficial in terms of overall health benefits, particularly with respect to weight control, lowered risk of diabetes, and cardiovascular disease prevention. The only change reported that could be potentially worrisome—depending on its nature (something we were unable to ascertain in this study)—is increased vitamin intake, mentioned by 46% of women reporting changes in this study or 19% of the total group. Very large doses of some vitamins or some combinations of vitamins as dietary supplements could potentially be harmful.13 Our results on the nature and extent of dietary changes are likely to be representative of those among an unselected series of women with newly diagnosed, nonmetastatic breast cancer. This study was based on a consecutive series of new patients. Very few exclusion criteria were used, and almost 90% of eligible women consented to participate and completed all evaluations. Nonetheless, we are aware that questions used to assess dietary changes were very simple and could not provide in-depth assessment of dietary habits. These questions were included, not because of a main interest in dietary change after breast cancer, but as one possible patient coping initiative that might reduce distress and improve quality of life independent of the psychological distress screening program tested in our original trial. Thus, we saw no reason to measure dietary habits using a validated instrument or to obtain information on baseline dietary habits or maintenance of dietary changes in the year after diagnosis. Only one question was used to assess meat intake ("viande" in French). Some dietary guidelines12,13 recommend that the intake of lean meat such as poultry ("volaille" in French) be increased relative to intake of red meats. Thus, it would have been of interest to have a separate item for poultry. Also, without information about baseline dietary habits for specific diet groups or items, we are unable to estimate the proportion of women making changes. For example, only 19% of women reported changing alcohol consumption, but the denominator here is the total group of 103 women. Alcohol consumption is generally low in our population, in these age groups, and it is thus possible that a large proportion of those women who in fact consumed alcohol changed their habits. We believe it unlikely that social desirability explains the high levels of reported positive changes, and this for several reasons. First, a large proportion of women also reported increased consumption of vitamins, a behavior for which there are no clear-cut guidelines and for which there is little support among medical professionals. In a similar vein, some women also reported increased consumption of desserts, which can contain large amounts of fat and sugar. Second, other investigators have also reported that the mean levels of dietary intakes reported at baseline in a population of nonmetastatic breast cancer patients who were enrolled on a randomized trial testing feasibility of dietary change were similar to the public health dietary guidelines recommended for health and for disease prevention.26 Finally, in another trial, women randomized to both the intervention and control groups significantly decreased their fat intake.40 These latter two studies provide additional evidence that women may already be attuned to prevailing opinions regarding the benefits of vegetables and hazards of fat consumption and modify dietary habits on their own initiative. The fact that these changes were more often reported by women with high initial levels of psychological distress lends weight to the idea that dietary change may be a coping strategy for some women. It is possible that certain problem-focused coping strategies used by individuals facing a stressful experience such as breast cancer can be effective in helping the individual to regain a sense of control. This interpretation is supported by findings from a dietary trial among nonmetastatic breast cancer patients that prerandomized women to dietary intervention or not. Of those randomized to the intervention group, 63% agreed to participate. Compared with women who declined, those accepting group assignation were less likely to express feelings of helplessness in social situations or to report a feeling that they did not have control over their own lives, and they showed a more positive reaction to adversity.41 As well, the profile of women reporting changes is consistent with that of women with more concerns about recurrence, who may have initiated dietary change in the hope of improving prognosis. Indeed, in response to questions about whether one could have any control over disease course, 51% of a group of American women felt they could have some influence, and cited attitudinal and behavioral changes such as dietary modifications as ones felt to give control.9 Our findings on declines in psychological distress associated with dietary change do not allow us to conclude that dietary change improved quality of life, as measured by distress. Although we can be fairly sure that these results are not the result of confounding, given the number of factors possibly associated with distress that were assessed and controlled in the analyses when necessary, it is likely that regression to the mean partly explains the greater decrease among women reporting dietary changes. Women reporting dietary change had higher initial distress levels. Regression to the mean refers to the phenomenon whereby a variable that is extreme on its first measurement will tend to be closer to the center of its distribution (or mean) for a later measurement.42,43 Thus, information from current randomized studies of dietary modification in women with nonmetastatic breast cancer24-26 will thus be crucial to a better understanding of the quality of life effects of dietary change. From a psychological point of view, however, even if dietary change did not cause the decline in distress we observed, the fact of acting and making changes may still have given women with certain coping styles a greater sense of control over the illness, a construct not measured in our study. Indeed, women regularly engage in a number of behaviors, the most common of which are standard surgical and adjuvant treatments of breast cancer, which have no immediate positive quality-of-life effects and very often negative ones, but which certainly increase feelings of control and of doing all that can be done to improve disease outcome. Our results support the idea that a substantial proportion of women are open to, and indeed report initiating, dietary change after breast cancer. This has also been observed in other settings.26 The changes reported in this study occurred among an unselected group of women in a clinical context where, to our knowledge, no special effort was made to motivate patients to initiate or maintain dietary change. The level of change reported seems noteworthy when one considers what is known both experientially and scientifically about the personal and social difficulties and barriers related to the adoption and maintenance of a new behavior involving lifestyle change.44-46 These observations suggest that many women with newly diagnosed, nonmetastatic breast cancer, particularly those who are young, have poorer prognosis, or have high distress, might be receptive to psychosocial care that includes dietary advice and help in overcoming barriers to changing dietary patterns. Indeed, in one study, women identified the need for information on nutrition and weight control as one of their greatest needs.47 Thus, at the least, our findings suggest that dietary information may help respond to the information needs of a substantial proportion of new patients, and particularly those with high distress. It may be important to think next about how to ensure that relevant dietary information is provided to all patients as an integral part of care in the period immediately after diagnosis and initial treatment. This period is increasingly thought to be critical for subsequent psychosocial adaptation to cancer.48-51 Dietary information might also provide general health and quality-of-life benefits independent of any as yet unclarified role in breast cancer prognosis, by helping women with weight control, obesity, and general physical form, all important for the health and quality of life of women generally.52,53 Weight gain has been reported in women treated for breast cancer, especially those undergoing chemotherapy.22 In public health terms, the period after diagnosis and the beginning of treatments is one when it is possible to provide information on a population basis, and thus potentially favorably affect the health and quality of life of this population of women. It is also the period when large numbers of patients experience acute worry about possible disease progression and experience high levels of psychological distress.2 We believe that attention to dietary questions provided through appropriate interaction with a multidisciplinary health care team during this period could be empowering for a substantial proportion of women in the process of coming to grips with breast cancer. Taken together, observations from this study suggest that there is an interest in and energy for dietary change that has not yet been maximally channeled into trying to improve the care, overall physical health, and quality of life of women facing breast cancer diagnosis, treatments, and fears about recurrence.
Support for this study was initially provided by a research grant from the National Cancer Institute of Canada with funds from the Canadian Cancer Society. E.M. and J.B. were National Health Research and Development Program National Health Research Scholars at the time this trial was originally conducted. E.M. is currently an investigator of the Canadian Institutes of Health Research/Social Sciences and Humanities Research Council/National Health Research and Development Program. We thank patients, social workers, surgeons, family physicians, nurses, and administrative staff of the Centre des Maladies du Sein Deschênes-Fabia, Hôpital du Saint-Sacrement. We are also grateful to Nicole Meunier for her work on patient recruitment, interviews, and other data collection and Myrto Mondor for work on statistical analyses and data presentation.
1. Maunsell E, Brisson J, Deschênes L, et al: Randomized trial of a psychological distress screening program after breast cancer: Effects on quality of life. J Clin Oncol 14: 2747-2755, 1996 2. Maunsell E, Dorval M, Drolet M, et al: Spouse and patient distress about breast cancer (preliminary results). Presented at: Reasons for Hope: Breast Cancer Research, Toronto, Ontario, Canada, June 18, 1999 3. Spencer S, Lehman J, Wynings C, et al: Concerns about breast cancer and relations to psychosocial well-being in a multi-ethnic sample of early-stage patients. Health Psychol 18: 159-168, 1999[CrossRef][Medline] 4. Kornblith AB: Psychosocial adaptation of cancer survivors, in Holland JC (ed): Psycho-Oncology. New York, NY, Oxford University Press, 1998, pp 223-241 5. Spencer SM, Carver CS, Price AA: Psychological and social factors in adaptation, in Holland JC (ed): Psycho-Oncology. New York, NY, Oxford University Press, 1998, pp 211-222 6. Watson M, Greer S: Personality and coping, in Holland JC (ed): Psycho-Oncology. New York, NY, Oxford University Press, 1998, pp 91-99 7. Rowland J, Massie MJ: Breast cancer, in Holland JC (ed): Psycho-Oncology. New York, NY, Oxford University Press, 1998, pp 380-402 8. Reardon KK, Aydin CE: Changes in lifestyle initiated by breast cancer patients: Who does and who doesn’t. Health Commun 5: 263-282, 1993 9. Taylor SE, Lichtman RR, Wood JV: Attributions, beliefs about control, and adjustment to breast cancer. J Pers Soc Psychol 46: 489-502, 1984[CrossRef][Medline]
10.
Lee M, Lin S, Wrensch M, et al: Alternative therapies used by women with breast cancer in four ethnic populations. J Natl Cancer Inst 92: 42-47, 2000
11.
Burstein H, Gelber S, Guadagnoli E, et al: Use of alternative medicine by women with early-stage breast cancer. N Engl J Med 340: 1733-1739, 1999 12. Canadian Cancer Society: Bien Manger Protège Contre le Cancer: Un Message Nutritionnel de la Société Canadienne de Cancer. Toronto, Ontario, Canada, Canadian Cancer Society, 1996 13. Canadian Cancer Society: Guide Alimentaire Pour Les Femmes Atteintes de Cancer du Sein. Toronto, Ontario, Canada, Canadian Cancer Society, 1998 14. Glanz K: Reducing breast cancer risk through changes in diet and alcohol intake: From clinic to community. Ann Behav Med 16: 334-346, 1994 15. Winters BL: Diet and cancer, in Holland JC (ed): Psycho-Oncology. New York, NY, Oxford University Press, 1998, pp 49-58 16. Lerner M: What science says about nutrition and cancer: Macronutrients, in Sexton J (ed): Choices in Healing: Integrating the Best of Conventional and Complementary Approaches to Cancer. Cambridge, MA, The MIT Press, 1994, pp 197-217 17. Holmes MD, Willett WC: Can breast cancer be prevented by dietary and lifestyle changes. Ann Med 27: 429-430, 1995[Medline] 18. Wynder EL, Taioli E, Rose DP: Breast cancer: The optimal diet, in Jabobs MM (ed): Exercise, Calories, Fat, and Cancer. New York, NY, Plenum Press, 1992, pp 143-153 19. Saxe G, Rock C, Wicha M, et al: Diet and risk for breast cancer recurrence and survival. Breast Cancer Res Treat 53: 241-253, 1999[CrossRef][Medline] 20. Holmes M, Stampfer M, Colditz G, et al: Dietary factors and the survival of women with breast carcinoma. Cancer 86: 826-835, 1999[CrossRef][Medline] 21. Marshall J: Diet and breast carcinoma survival: An abundance of hope, a dearth of evidence. Cancer 86: 751-753, 1999[CrossRef][Medline] 22. Chlebowski R, Rose D, Buzzard I, et al: Adjuvant dietary fat intake reduction in postmenopausal breast cancer patient management: The Women’s Intervention Nutrition Study (WINS). Breast Cancer Res Treat 20: 73-84, 1992[CrossRef][Medline] 23. Byers T, Rock CL, Hamilton KK: Dietary changes after breast cancer: What should we recommend? Cancer Pract 5: 317-320, 1997[Medline]
24.
Chlebowski R, Blackburn G, Buzzard I, et al: Adherence to a dietary fat intake reduction program in postmenopausal women receiving therapy for early breast cancer: The Women’s Intervention Nutrition Study. J Clin Oncol 11: 2072-2080, 1993 25. Chlebowski RT, Blackburn G, Winters B, et al: Long term adherence to dietary fat reduction in the Women’s Intervention Nutrition Study (WINS). Proc Am Soc Clin Oncol 19: 78a, 2000 (abstr 302) 26. Pierce JP, Faerber S, Wright FA, et al: Feasibility of a randomized trial of a high-vegetable diet to prevent breast cancer recurrence. Nutr Cancer 28: 282-288, 1997[Medline] 27. Nezu AM, Nezu CM, Friedman SH, et al: Helping Cancer Patients Cope. Washington, DC, American Psychological Association, 1998 28. Smith KW, Avis NE, Assman SF: Distinguishing between quality of life and health status in quality of life research: A meta-analysis. Qual Life Res 8: 447-459, 1999[CrossRef][Medline] 29. Bellerose C, Lavallée C, Chénard L, et al: Santé Québec: Et la Santé, Ça Va en 1992-1993? Rapport de l’Enquête Sociale et de la Santé 1992-1993 (vol 1). Québec, Canada, Santé Québec, 1995 30. Boyer R, Préville M, Légaré G: La détresse psychologique dans la population du Québec non institutionalisée: Résultats normatifs de l’enquête Santé Québec. Can J Psychiatry 38: 339-343, 1993[Medline] 31. Emond A, Guyon L, Camirand F: Et la Santé, Ça Va? Tome I: Rapport de l’Enquête Santé Québec. Québec, Canada, Ministère de la Santé et des Services Sociaux, 1988 32. Perrault C: L’Enquête Santé Québec et la Santé Mentale des Québécois: Cadre Conceptuel et Méthodologie. Santé Mentale au Québec 14: 132-143, 1989 33. Maunsell E, Brisson J, Deschênes L: Psychological distress after treatment for breast cancer: A comparison of partial and total mastectomy. J Clin Epidemiol 42: 765-771, 1989[CrossRef][Medline] 34. Maunsell E, Brisson J, Deschênes L: Arm problems and psychological distress after surgery for breast cancer. Can J Surg 36: 315-320, 1993[Medline] 35. Maunsell E, Brisson J, Deschênes L: Psychologic distress after initial treatment for breast cancer: Assessment of potential risk factors. Cancer 70: 120-125, 1992[CrossRef][Medline] 36. Dorval M, Maunsell E, Deschênes L, et al: Type of mastectomy and quality of life for long term breast carcinoma survivors. Cancer 83: 2130-2138, 1998[CrossRef][Medline] 37. Dorval M, Maunsell E, Deschênes L, et al: Long-term quality of life after breast cancer: Comparison of 8-year survivor with population controls. J Clin Oncol 16: 487-494, 1998[Abstract] 38. Colton T : Statistics in Medicine. Boston, MA, Little Brown & Co, 1974, pp 210-211 39. Grindel C, Cahill CA, Walker M: Food intake of women with breast cancer during their first six months of chemotherapy. Oncol Nurs Forum 16: 401-407, 1989[Medline] 40. Nordevang E, Callmer E, Marmur A, et al: Dietary intervention in breast cancer patients: Effects on food choice. Eur J Clin Nutr 46: 387-396, 1992[Medline] 41. Holm L, Norvedang E, Ikkala E, et al: Dietary intervention as adjuvant therapy in breast cancer patients: A feasibility study. Breast Cancer Res Treat 16: 103-109, 1990[CrossRef][Medline] 42. Campbell D, Kenny D: A Primer on Regression Artifacts. New York, NY, The Guilford Press, 1999
43.
Davis C: The effect of regression to the mean in epidemiologic and clinical studies. Am J Epidemiol 104: 493-498, 1976 44. Ajzen I, Fishbein M: Understanding Attitudes and Predicting Social Behavior. Englewood Cliffs, NJ, Prentice-Hall, 1980 45. Bandura A: Social Foundations of Thought and Action: A Social Cognitive Theory. Englewood Cliffs, NJ, Prentice-Hall, 1986 46. Fishbein M, Ajzen I: Belief, Attitude, Intention and Behavior: An Introduction to Theory and Research. Don Mills, Ontario, Canada, Addisson-Wesley, 1975 47. Feather B, Wainstock J, Remington A, et al: Postmastectomy educational needs and social support. J Cancer Educ 3: 135-144, 1988[Medline] 48. Ruckdeschel JC, Blanchard CG, Albrecht T: Psychosocial oncology research: Where we have been, where we are going, and why we will not get there. Cancer 74: 1458-1463, 1994[CrossRef][Medline] 49. Bloch S, Kissane DW: Psychosocial care and breast cancer. Lancet 346: 1114-1115, 1995[CrossRef][Medline]
50.
Fallowfield L: Psychosocial intervention in cancer. BMJ 311: 1316-1317, 1995 51. Sorensen M, Liu ET: With a different voice: Integrating the psychosocial perspective into routine oncology care. Breast Cancer Res Treat 35: 39-42, 1995[CrossRef][Medline]
52.
Fine J, Colditz G, Coakley E, et al: A prospective study of weight change and health-related quality of life in women. JAMA 282: 2136-42, 1999 53. Kawachi I: Physical and psychological consequences of weight gain. J Clin Psychiatry 60: 5-9, 1999 (suppl) Submitted July 14, 2000; accepted October 29, 2001. This article has been cited by other articles:
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Copyright © 2002 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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ABSTRACT
INTRODUCTION
