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© 2001 American Society for Clinical Oncology Determinants of the Use of Complementary Therapies by Patients With CancerFrom the Department of Social Medicine and School of Public Health, Department of Hematology, and Department of Oncology, Hadassah Medical Center, Hebrew University; Department of Oncology, Shaare Zedek Medical Center, Jerusalem; and Department of Oncology, Chaim Sheba Medical Center, Tel Hashomer, Israel. Address reprint requests to Ora Paltiel, MD, Department of Social Medicine, Hadassah Medical Center, PO Box 12000, Jerusalem 91120, Israel; email: ora{at}vms.huji.ac.il
PURPOSE: We performed a survey of Israeli oncology patients to examine the extent of their use of complementary therapies (CT) and to compare sociodemographic, psychologic, and medical characteristics, attitudes, and quality of life of users and nonusers of CT. PATIENTS AND METHODS: Questionnaires were administered to 1,027 patients attending ambulatory and inpatient hematology or oncology facilities at three hospitals. Medical information was extracted from charts. Univariate and multivariate comparisons of users and nonusers of CT were performed. RESULTS: A total of 526 participants (51.2%) had used CT since their diagnosis, and 357 patients (34.9%) had used CT recently (in the past 3 months). Factors that multivariate analysis found to be significantly associated (P < .05) with recent CT use were as follows: female sex; age 35 to 59 years; more education; coming to the hospital by private car; advanced disease status; having a close friend or a relative with cancer; and attending support groups or individual counseling. After controlling for these factors, individually examined psychosocial variables associated with recent CT use included the following (odds ratios [OR] with 95% confidence intervals [CI]): needs unmet by conventional medicine (OR, 2.76; 95% CI, 1.95 to 3.89); helplessness (OR, 1.39; 95% CI, 1.0 to 1.91); incomplete trust in the doctor (OR, 1.49; 95% CI, 1.08 to 2.06); and changed outlook or beliefs since the diagnosis of cancer (OR, 1.47; 95% CI, 1.07 to 2.02). Functional quality of life (including physical, emotional, social, and role function) and symptom (fatigue and diarrhea) scores were significantly worse for recent CT users compared with nonusers, controlling for age, sex, and current disease status. CONCLUSION: Characteristics associated with CT use include age, sex, education, and advanced disease. Significant associations between CT use and attending supportive psychotherapy, unmet needs, helplessness, and worse emotional and social function indicate considerable distress, suggesting that increased attention to psychosocial needs within oncologic settings is warranted.
THE USE OF THERAPIES other than those offered by conventional medical practitioners has been gaining acceptance throughout the world. In particular, many patients with cancer have been drawn to the use of unconventional therapies.1 The traditional view that these modalities are used by desperate patients or "hopeless cases" has been shown to be untrue.2,3 Growing consumerism on the part of health care users, including patients with cancer, has even resulted in a move toward the availability of complementary therapy (CT) in the conventional hospital setting, including oncology centers.4,5 Few of these modalities have been rigorously tested6; most remain unproved, yet popular.7 Patients who self-select CT represent a subgroup of patients with particular needs or characteristics that require special attention or consideration by the medical community. There has been concern that patients with cancer will desert potentially curative conventional therapies in favor of unproved methods.8 Other concerns have included toxicities associated with nonconventional therapies for cancer6 or possible interactions with chemotherapy. According to two studies, patients with cancer treated outside of conventional facilities have been found to have a poorer quality of life (QOL)8 and possibly shorter survival times9 than those who received their treatment in conventional facilities. In fact, patients with cancer rarely opt out of conventional therapy altogether (8% in a 1984 survey10), and in most cases, alternative medicine is used to complement, not replace, conventional therapy.10-12 The factors that motivate patients to turn to alternative therapies have been extensively studied in the general population13 and in the population of patients with breast cancer.14 Because patients with cancer generally face a situation that is subjectively more frightening and less controllable15 than other chronic or life-threatening diseases, it is important for the medical community to understand the factors motivating them to use CT. Studies of this sort outside of North America and Western Europe are particularly lacking. We performed a cross-sectional study in three oncology centers in Israel with the following aims: to assess the extent of past and current use of CT among Israeli patients with cancer; to examine the sources of referral, type of practitioner, and sources of funding among CT users; and to compare the characteristics of users and nonusers of CT in terms of medical history, sociodemographic data, and psychosocial factors and attitudes, as well as QOL, doctor-patient relationship, and self-assessed health status.
Study Population and Procedures The study included patients 18 years of age or older diagnosed with cancer at least 2 months before the interview, who gave signed informed consent to be interviewed. Patients judged to be in a preterminal state or too ill to complete the interview were excluded. The interviews took place in the oncology and hematology outpatient clinics, oncology and hematology day care centers, and inpatient departments at three hospitals in Israel, two in the city of Jerusalem (the only two hospitals with oncology departments in Jerusalem) and one in the city of Tel Aviv. All potentially eligible patients attending the clinics were approached. The study participants thus consisted of a convenience sample of all available patients in those centers. Interviews were performed by social workers and other trained interviewers who approached patients as they waited or received treatment in these settings. The questionnaire was administered in Hebrew, English, or Russian. Arabic-speaking patients were interviewed separately in a companion study. The majority of the interviews were face to face, with occasional self-administration of parts of the questionnaire, such as the section on QOL. Interviews took place between April 1997 and November 1998.
Definition of CT
Questionnaire
Medical Information
Ethics
Statistical Analysis
Data analysis was performed using SPSS software (SPSS, Chicago, IL). Users of CT were defined as those who reported usage of at least one CT. For all statistical analyses, a two-sided P value of .05 was considered statistically significant. Relations between categorical variables were assessed by the Logistic regression models were constructed for those who had ever used (since cancer diagnosis) CT and recent use (in the last 3 months); variables found to be significantly associated with CT on univariate analysis were added in a forward stepwise fashion in groups (first sociodemographic variables, then medical variables, then psychosocial variables to construct a basic predictive model). Current attitudes or feelings, including those pertaining to the doctor-patient relationship, were assessed individually in terms of their association with the recent use of CT after controlling for variables in the basic model. The criterion for variable entry was P = .05. Data from patients with missing values were excluded from the logistic models.
Final Study Population We excluded 106 participants who were interviewed: 56 were in retrospect ineligible (20 because their diagnosis was not cancer and 36 because they were diagnosed less than 2 months before the interview), 20 did not complete the questions regarding CT use and therefore could not be classified as users or nonusers of CT, and 35 were excluded for a variety of other reasons. Data analysis was performed on the portion of the study population for whom medical information was available (1,027 participants [92.8%]). Because some patients who were interviewed in the clinic waiting area were called in to see their doctors before completing the entire questionnaire, 98 patients had no or incomplete responses to the QOL questionnaire.
The final study population comprised 715 women (69.6%) and 312 men (30.4%). The mean age was 56.6 years (SD, 14.4; range, 18 to 88). The majority (60.7%) of patients interviewed were born outside Israel, approximately half (50.3%) professed to be secular, and 55.6% reported 13 or more years of education. One hospital (A) contributed 55.3% of the participants, with the others contributing 12% and 32.7%, respectively. Approximately one half of the patients (53.8%) were interviewed in the outpatient clinic, whereas the remainder were interviewed in an active care setting (either day center or inpatient department). A flow diagram of the study population is presented in Fig 1.
Use of CT Of the 1,027 participants, 526 patients (51.2%) had used at least one type of CT since the time of their cancer diagnosis (hereafter "ever-use") and 357 patients (34.8%) had used CT in the past 3 months (hereafter "recent use"). Among users, the median number of CT modalities used was two (range, 1 to 11). Table 1 shows the use of CT in descending order of frequency, referral patterns, type of practitioners, and source of funding for various CTs for ever-users. The majority of patients stated that they were advised to use CT by their friends or family. This was true for all but two modalities. The only therapies to which patients commonly reported referral by their physician or other members of the medical staff were relaxation therapy (25.1%) and acupuncture (28%). Relaxation therapy was almost always used in combination with other therapies. CT was administered by a wide variety of practitioners, but in the case of homeopathy and acupuncture, more than 50% of the patients reported treatment by medical doctors. For all modalities other than relaxation therapy, the patients funded the treatment themselves in more than 70% of cases.
Some of the CT users had been users before their diagnosis of cancer; however, not all users continued with a previous modality after their cancer diagnosis ( Table 2). For example, of 189 users of homeopathy, 49 had used this modality before their illness. Conversely, of 116 patients who had used homeopathy before their cancer diagnosis, 67 patients (57.8%) did not use this modality after their diagnosis (Table 2). For most therapies, the majority of users had begun using the particular modality only since receiving a diagnosis of cancer. In the case of acupuncture, more patients had stopped using this modality since the cancer diagnosis than started after their diagnosis.
Univariate Analysis Sociodemographic variables. Table 3 shows factors significantly associated with use of CT at any time since diagnosis or in the last 3 months. In terms of sociodemographic factors women, patients aged 35 to 59, those with post–high school education, and native Israelis were more likely to be recent or ever-users. Religiosity was associated with ever-use but not with recent use. In one hospital (B) where interviewed patients were mainly undergoing active therapy, significantly increased recent use, but not ever-use, of CT was observed. We had no measure of income, but we found that those who came to the hospital in a private car as well as those who were currently working were more likely to be users than those who came by taxi or bus and those who were not currently working.
Medical and disease variables. Table 4 shows the association of medical variables with CT use. Ever-use of CT was more prevalent among patients with breast, hematologic, lung, and brain cancer (P = .001) compared with other sites. Recent use was particularly high among patients with breast and lung cancer and lower in patients with gastrointestinal and prostate cancer (P = .0001).
For every site except lung cancer, recent CT use was higher for women compared with men (for example, among patients with hematologic malignancies, 32% of women had used CT in the last 3 months compared with 15% of men; P = .02; data not shown). Factors not associated with CT use included stage at the time of diagnosis, Karnofsky status at the time of diagnosis, comorbid conditions (data not shown), and the presence of multiple cancers (data not shown). There was a nonmonotonic association between time since diagnosis and ever-use of CT, but not with recent use. Current disease status was highly associated with recent (P < .001) and ever-use (P = .005). Use of chemotherapy in the past or at the present time was associated with ever-use (P = .002) and recent use (P < .001). Similar associations were not seen with radiation therapy (P > .05) or hormonal therapy (data not shown). Patients who had used painkillers in the past week were more likely to be recent (P = .002) or ever-users (P = .028), but no such relationship was observed with sleeping pill or tranquilizer use. Psychosocial variables. Table 5 shows the association between psychosocial variables and ever-use or recent use of CT. Patients who felt any degree of helplessness were more likely to be users than those who felt no sense of helplessness whatsoever (P < .001). Participants who reported a change in their outlooks or beliefs since becoming ill were more likely to use CT (P = .001 for ever-use or recent use). Those who felt that their situation would change in the future (improve or deteriorate) were more likely to be recent users (38.8% and 37%, respectively) compared with those who felt their situation would remain the same.
A strong association was noted between use of individual supportive counseling or support groups and use of CT. These two variables were combined into a single variable denoting use of supportive psychotherapy for the multivariate models. Psychosocial variables that were not associated with use of CT were sense of control (P = .3) and having someone to turn to for practical help or emotional support. When asked whether "regular or conventional therapy meets my needs," 58.9% of users agreed with the statement, compared with 82.2% of nonusers (P < .001). Patients who had a close friend or family member with cancer were more likely to be recent users and ever-users. Doctor-patient relationship. No differences were found between the users and nonusers in the overall questionnaire score; therefore, single items were examined. Recent CT users comprised 48% of those who felt they could not consult their doctor regarding CT, compared with 32.7% among those who could consult their physician (P < .001). Recent users were more common among those who expressed lack of trust in the doctor (42.4%) compared with those who trusted their doctor completely (30.1%, P < .001). These two aspects of the doctor-patient relationship were also associated with ever-use (P = .005 and P < .001, respectively). The doctor’s approachability ("If I have problems, I can turn to my doctor"), encouragement, inclusion of patient in the treatment plan, explanations of illness or treatment to the patient, or explanation to the family were not found to differ between users and nonusers.
Multivariate Analysis
Variables associated with odds ratios of more than 2 for recent CT use were as follows: more than 13 years of education; current advanced disease status; transport to hospital in a private car; and needs unmet by the regular medical system.
QOL
This study found that approximately one half of patients with cancer in various settings in Israel have used CT since their diagnosis, and approximately one third can be classified as recent users. These findings are comparable to those reported by some US investigators10,11 as well as by investigators in centers in Europe.1 The prevalence of use is somewhat lower than a recent report from a large US comprehensive cancer center.19 The common modalities of CT used were homeopathy, relaxation therapy, and reflexology. Most therapies were self-funded by the patients and referral was generally by family or friends, consistent with the observation that word of mouth is a usual method of finding CT practitioners.20 The media also played a role, as has been reported in Italy.21 A significant minority of CT users had used these therapies before their cancer diagnosis. The sociodemographic factors associated with CT use were consistent with those reported in international surveys20,22 and include female sex and younger (but not youngest) age group (aged 35 to 39 years). Similarly, higher education and income have been identified as predictors for use in international surveys13,14,20,22,23 as well as in a survey of the general population in Israel.24 In our study, higher education as well as coming to the hospital in a private car, both indirect measures of income, were associated with CT use. After controlling for sociodemographic variables, advanced disease was the only medical factor that remained significantly associated with CT use. A poor prognosis may lead to increased levels of concern or distress and a desire to explore all possible options. Previous experience with cancer through a close friend or family member, a factor that may also increase psychologic distress, was also more frequent among users of CT. There was greater use of individual or group psychologic support by users of CT. A strong association between the use of psychologic support or therapies and CT use has been previously observed.11,14 The use of supportive counseling implies increased psychologic needs on the one hand and access to and willingness to use available psychosocial support services on the other. Some studies have even included psychologic therapies as CT.25 Although patients with cancer turn to CT in the hopes of improving their QOL,14 consistent with other studies, we have found no evidence of improved QOL among users of CT.8,11 In fact, scores on several functional and symptom scales were significantly worse for users than nonusers, even after controlling for disease status. Poor emotional status was also observed by Burstein et al11 and invites the question as to whether emotional and social distress or despair are the prime factors that motivate patients with cancer to use CT. Furthermore, one might ask whether increased symptoms such as diarrhea may be due to CT or diets chosen by CT users. Given the cross-sectional nature of our study, no causal inference may be made regarding CT use and poorer QOL. We found higher CT use among those who reported a change in their outlook or beliefs since they were diagnosed with cancer. Eidinger and Schapira26 reported that 34% of patients with advanced cancer became more religious since learning they had cancer. Similarly, Astin13 found in a general population survey that "a transformational experience" was associated with use of alternative therapies (odds ratio, 1.76). Thus, "the persuasive appeal of alternative medicine"27 may include its emphasis on religion and spiritual experience. Although the doctor-patient relationship questionnaire was not associated with CT as a single scale, individual aspects of this relationship were found to be determinants of recent CT use. Complete trust in the doctor was less likely to be reported among users. Furthermore, users were less likely to be able to consult with their doctors regarding alternative treatments. Cassileth et al10 reported that doctor-patient relations were worse among patients with cancer who received conventional and CT compared with those who received conventional therapy alone. Previous American and Israeli surveys13,28 in the general population did not show associations between doctor-patient dissatisfaction and CT use. Incomplete trust in the doctor, as measured in our survey, may reflect a worldview that does not accept paternalistic or authoritarian medicine, rather than a poor relationship with the physician among users. After controlling for the basic factors in the multivariate analysis, the factor most strongly associated with use of CT was the belief that conventional therapy did or did not meet the patients’ needs. Although this may seem to be a tautology, in fact, 76 (17.6%) of 427 never-users felt that regular treatment did not meet their needs and 187 (41%) of 455 of users felt that conventional therapy did meet their needs. The issue of unmet needs is a recurrent theme in research in alternative therapies in cancer. Because details were not obtained in the study questionnaire, we can only speculate as to the particular needs that our study participants felt were unmet. Conventional cancer care may be lacking in spiritual elements, the provision of hope,29 the encouragement for self-care, and the laying on of hands. CT is often offered in a positive, optimistic style30 by a practitioner who spends more time per encounter than his or her conventional-medicine colleague,31 listens carefully, and provides emotional support.14 Furthermore, conventional therapies are considered poisonous,32 whereas alternative therapies are viewed as natural, nontoxic,2 and health-promoting.3 Although control and freedom of choice have emerged as important motivating factors for seeking CT,33 we found no differences in patients’ perceptions of their own control during their life between users and nonusers, despite the differences in current disease status. This study has several limitations. Although a broad spectrum of patients with cancer were interviewed, the study population did not represent a systematic sample of patients with cancer in Israel. However, all potential oncology patients in Jerusalem were in the sample frame. Men with prostate cancer seem to be underrepresented, possibly because their follow-up tends to be in urology clinics. The interview generally took place in open conditions that did not guarantee full privacy, a factor that may have limited the quality of some of the responses. Because of the need to obtain medical data, the questionnaire could not be entirely anonymous, and several patients refused to participate for this reason. We have no way of assessing the eligibility of patients who refused; thus, the degree of nonresponse among potentially eligible subjects could not be accurately measured. Nevertheless, this study had a large sample size, and a wide variety of treatment settings, disease sites, and stages of illness were represented. We had no measure of the use of alternative therapies outside of the context of conventional medicine, although other studies have shown that this represents a small percentage of patients with cancer.10,34 Notwithstanding these limitations, many of the associations are consistent with previously published studies attesting to the generalizability of our findings. Because the use of alternative therapies may be a sign of distress, asking patients about their use may identify those in particular need of supportive services35,36 for which evidence of efficacy exist.37 Our findings lead us to conclude that psychosocial care and a supportive holistic atmosphere should be further developed within oncologic facilities in addition to the many services that already exist, including in the three centers that took part in the study.
Supported in part by grants from the Office of the Chief Scientist of the Israel Ministry of Health (grant no. 3779), Keren Sapir of Mifal Hapais, and the Israel Cancer Association (grant no. 970108-C). We thank Noémie Cohen, the study coordinator, and Elizabeth Render and Rosa Sakler, the interviewers. We also thank Nora Goldberg, Dikla Negbi, and Hadass Shasha for data abstraction from medical records and all the nurses who facilitated the execution of our study in the oncology and hematology departments at Hadassah, Shaare Zedek, and Tel Hashomer-Sheba Medical Centers. We also thank Professor Raphael Catane for his cooperation.
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Copyright © 2001 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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ABSTRACT
INTRODUCTION
value of 0.05 and power of 80%. This minimal sample size was enlarged to enable multivariate adjustment (reported here), as well as longitudinal measures and survival analysis, which will be reported separately. The final sample size has a power of more than 99% to detect the above-mentioned differences in QOL scores. 
2 test. Differences in means between users and nonusers were tested by the t test for independent means. The total score as well as single items of the doctor-patient relationship questionnaire were examined. The Crohnbach’s 
