Psychological intervention in cancer patients: a randomized study

General Hospital Psychiatry 23 (2001) 272–277

Psychological intervention in cancer patients: a randomized study Lea Baider, Ph.D.a,*, Tami Peretz, M.D.a, Pnina Ever Hadani, M.P.H.b, Uwe Koch, M.D, Ph.D.c b

a Sharett Institute of Oncology, Hadassah University Hospital, 91120 Jerusalem, Israel Department of Health Administration, School of Public Health, Hebrew University, Hadassah Jerusalem, Israel c Department of Psychological Medicine, University of Eppendorf Hamburg, Germany

Abstract We examined the long-term effects of a behavioral intervention on the psychological distress of patients recently diagnosed with localized cancer, who were being treated at Hadassah University Hospital. All 116 patients who met the inclusion criteria (49 men and 67 women) were randomized into an intervention group and a control group on a 3:1 basis. The intervention chosen was Progressive Muscle Relaxation with Guided Imagery, which is intended to decrease psychological distress and increase the patient’s sense of internal control. The Brief Symptom Inventory (BSI) and the Impact of Events Scale (IES) were used to assess psychological distress within 1 month of diagnosis, 3 months later (shortly before starting intervention), and 6 months after the end of the intervention. At the final assessment, the effect of the behavioral intervention on psychological distress was positive. The effect was relatively modest but statistically significant when assessed in terms of the Global Severity Index (GSI) (a decrease of 2.3 points in the GSI of the treatment group as compared to an increase of 1.2 points in the GSI of the control group P⫽.005). Despite these moderately positive findings, we suggest that the results might be more meaningful if cancer patients are first screened for psychological distress to exclude those with a low distress level that does not justify intervention, and only then randomized for participation in the study. © 2001 Elsevier Science Inc. All rights reserved. Keywords: Psychological intervention; Distress; Randomized study

1. Introduction The immediate effects of time-limited behavioral group intervention in cancer patients have been extensively described. In the past 25 years, numerous psychological interventions have been tried in an attempt to control the psychological effects of distress that arise as a result of cancer treatments and to improve patients’ quality of life functionally and emotionally [1–3]. The first controlled studies on psychological interventions were reviewed in 1983 by Watson [4], who concluded that “to the question of whether support programs benefit patients, the answer is a qualified yes.” A decade later, Meger and Mark [5] published a meta-analysis of randomized studies that examined the efficacy of psychosocial interventions in improving psychological functioning. Like Watson, these authors reached the conclusion that psycho* Corresponding author. Tel.: ⫹972-2-566-4701; fax:⫹972-2-5663686. E-mail address: [email protected] (L. Baider)

logical intervention yielded significant beneficial effects, both on the emotional adjustment of cancer patients and on symptoms related to disease and treatment. Furthermore, attitudes such as hopefulness have been shown to cause decreased morbidity and generally high quality-of-life scores in long-term breast cancer survivors [6]. The importance of social support for patients’ adaptation to the illness has been underscored in large community cohort studies. Population-based studies of adults with cancer indicate that unmarried patients and patients lacking social support have a decreased overall survival and poorer treatment response than married people [7– 8]. The role of social support has highlighted its potential contribution as a factor in moderating outcome for survival and better adaptation [9 –11]. Spiegel and colleagues [12] reported mortality data for 36 no-treatment control and 50 intervention women with metastatic breast cancer who had participated in a group support intervention to enhance adjustment and social support, and reduce disease symptoms. Walker et al. [13], in a prospective randomized study of women with large tumors or locally advanced breast cancer,

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showed that relaxation and guided imagery enhance mood and improve coping ability. “Fighting spirit” imagery was used by many of the patients as a coping tool. Meger and Mark [5] point out that most of the randomized controlled psychological studies have been carried out in the United States, and that in most cases the participants were women diagnosed with breast cancer [14]. Consequently, there is a need for such studies from other parts of the world, as well as for studies that include both male and female patients with different types of cancer. Such studies would add to the scant literature on the long-term effects of psychological interventions in cancer patients of both genders [15–18]. The aim of the present study was to gain a better understanding and to measure the psychological effects of a specific kind of behavioral intervention on psychological distress in cancer patients 6 months after the intervention was terminated. We were also interested in finding out why some patients drop out of a psychological intervention program. 1.1. Subjects and methods 1.1.1. Patient population The sample population comprised newly diagnosed adult cancer patients being treated at the Institute of Oncology at Hadassah University Hospital, Israel. The rationale for the selection of our patient population was based on the understanding that the stressful impact of the initial diagnosis of cancer would cause high levels of psychological distress. Furthermore, for patients within the randomization study who participated in the psychological intervention, they would be provided with skills and tools to reduce the impact of cancer distress and enhance their adaptive coping styles. Criteria for inclusion in the study were: a recent diagnosis (within the month before starting behavioral intervention) of a type of cancer that occurs in both sexes and for which the projected survival time is at least 3 years; localized disease and no active chemotherapy protocol at the time of the intervention to reduce confounding factors; a Karnofsky performance score of not less than 75; no other physical or mental illnesses and no other comorbidity; being Jewish and proficient in Hebrew; residency in Israel for at least 10 years and current residency in Jerusalem. Patients, who at the time of the study participated in other individual or group psychological treatments, were excluded from our final statistical analysis. During 1998, consecutive patients who met all of the above criteria were invited to participate in the study. Of these patients, 47 had colo-rectal cancer (T1A;N0M0;T2BN0M0), 27 had stomach cancer, 29 had melanoma, 27 had non-Hodgkin’s lymphoma, and 11 with other diag-noses. Most of the staging of all diagnoses was in the T1N0M0 or T2N0M0 category [13].1 1 The TNM Classification of Malignant Tumours describes the anatomic extent of cancer in terms of the primary tumor site (T); the regional lymph nodes (N) and distant metastasis (M) [19].

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Of a total of 116 patients who were invited by the treating physician to participate in the study, 26 refused because of lack of interest. There were no differences in gender distribution, marital status, religiosity, age, medical diagnosis, or Karnofsky scores between these 26 patients and the 90 patients who agreed to participate. 1.2. Instruments All participants signed an informed consent form and supplied a written detailed sociodemographic information. A complete medical record was provided by their treating physician. Levels of psychological distress were assessed by the use of two self-report questionnaires. The Brief Symptom Inventory (BSI), is a 53-item assessment tool used extensively to assess psychological distress (determined by the individual’s score on the Global Severity Index [GSI]). The measure has nine specific subscales (somatization, obsessive-compulsive, interpersonal sensitivity, depression, anxiety, hostility, phobic anxiety, paranoid ideation, and psychoticism). The raw scores are converted to T scores, with an accepted cutoff point for psychopathology of 63 on the GSI or scores of 63 on three of the subscales. Higher scores on the BSI indicate higher distress. Its internal reliability in the present study was excellent (Cronbach’s ␣⫽0.94). In the present study, only the total GSI score was used. The second questionnaire used was the Impact of Events Scale (IES), a 15-item self-report composed of two scales that assess reactions to a traumatic event, such as disease. Although there is no clear cut-off point between normal and pathological reactions, a score above 24 on the IES is usually regarded as pathological. The IES is composed of both Avoidance and Intrusion scales. The Hebrew versions of the BSI and the IES have been validated and used in many studies dealing with cancer patients. In this study, the internal coefficient Cronbach’s alpha was 0.93 for the GSI and 0.86 for both Intrusion and Avoidance.

2. Methods At the first assessment (T1), carried out within 1 month of diagnosis, patients were randomized into an intervention group and a control group on a 3:1 basis. The rationale for such randomization was that in previous studies the rate of refusal to participate in group intervention was very high. The meaning of the randomization was explained to the patients, and they were required to agree to it in writing. Patients in the control group received the standard care given to all patients, and did not participate in the psychological intervention. The second assessment (T2) took place 3 months later, before the patients in the intervention group began psychological intervention. The third assessment (T3) took place 6 months after the end of the psychological intervention.

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2.1. Statistical analysis For the univariate analysis, the three groups (treatment, control and refusal) were compared using a ␹2 test for categorical variables and ANOVA for continuous variables. GSI, Intrusion, and Avoidance are measures that would be expected to change between T2 and T3 if the intervention has long-term effects. We, therefore, used the differences in these scores between T2 and T3 as the dependent variables when assessing the efficacy of the intervention. To assess the possible effect of the intervention on the differences in scores between T2 and T3, twelve separate Multiple Stepwise Regressions were calculated. The dependent variables in these twelve regressions were the difference between T2 and T3 for GSI, Intrusion and Avoidance, and for each of the nine BSI scales. The independent variables were gender, age, marital status, education, religiosity, Karnofsky score, stage of cancer, intervention or control group, and the dependent variable level at T2. 2.2. Intervention A number of research studies have shown that psychological intervention can contribute significantly to both psychological and physical health outcomes in patients with cancer [5,20]. In particular, behavioral training—such as guided imagery with progressive muscle relaxation— has been used in several cancer interventions to help reduce psychological stress due to the cancer diagnosis [21–23]. Guided imagery in conjunction with relaxation was popularized beginning in the late 1970s [24]. Since these early studies, a number of investigations have employed similar techniques in order to provide patients with an easy tool for the enhancement of adjustment and a better sense of body-mind control. Relaxation techniques have been found to have efficacy in reducing psychological symptoms, such as anxiety and physical symptoms, associated with the disease [23,25]. The intervention selected was Progressive Muscle Relaxation with Guided Imagery. The primary objective of this psychological intervention is to decrease psychological distress and increase the patient’s sense of internal control, thus enabling the patient to mobilize better coping resources and derive improvement in the quality of life. Relaxation and guided imagery are designed to focus attention, release both physical and mental tensions, and allow the patients to channel their energies more usefully. During the intervention an attempt was made to induce patients to imaginatively create an idea or mental visualization. In guided imagery, patients use the therapist’s verbal stimulus to create images of something they wish to create for themselves, and then continue to focus on the perception until it becomes a clear, subjective reality. The group is exposed to specific positive thoughts conducive to an inner sense of calm, control, and diminished psychological distress. A modified form of Jacobson’s method for Progressive Muscle Relaxation [26] was used, with passive concentra-

tion on breathing. Relaxation is achieved by systematic tensing and relaxing of different parts of the body. The therapist describes comfortable sensations in different muscle groups, progressing from head to feet and returning to different body parts (i.e., eyes, face, abdomen). The patients behave as passive observers, not actively initiating any responses but simply taking note of what is happening in and around their bodies. They are taught how to observe ongoing events without evincing a particular desire or need to change anything, thus fostering the ability to observe and “let go”. The procedure is not something that is “done” to the patients, but rather enhances their capacity for a certain style of concentration [27,28]. The psychological intervention was conducted in groups of 8 to 10 participants. Sessions were held in a quiet room with comfortable reclining chairs. Patients were taught to create and maintain a special relationship with the space, chair and surroundings, and to imbibe the quiet atmosphere. Sessions were held weekly for 6 consecutive weeks and lasted for 60 min. All sessions began with 5 to 8 min of easy physical exercising of those parts of the body on which that session would be focused. Patients exercised only as much as their physical condition permitted. Each patient was provided with a small notebook and given a simple weekly homework assignment related to that week’s session. At the beginning of each session, the therapist discussed the homework experience and emphasized the necessity and importance of completing the assignment. No attempt was made to determine which patients did or did not do the home exercises. All groups were led by the same therapist, using the specific body-relaxation and guided-imagery topic for each session, as follows: 1. Remembering and finding one’s own meaningful place: capturing one’s own space and time; a place that provides security and fulfillment in a congenial atmosphere. 2. A walk by the seashore: integration of calmness and power; finding a balance between apparently contradictory forces. 3. Discovering the path in the forest: positive control of life; the forest as a metaphor for the power of survival; finding light among the trees in the forest. 4. Creating an internal garden of flowers: creating our own internal beauty; positive internal objects of different colors, shapes and fragrances. 5. Discovering oneself—the open mirrors: knowing one’s inner self; accepting oneself in the here and now; projecting to the future. 6. Recapturing oneself—returning to one’s own internal place: creating and developing a protective environment that is secure and healthy, belonging only to oneself; a place that is always there when needed.

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Table 1 Background and psychological condition at T1

Sex: Male Female Married: Yes No Religiosity: Secular Religious Age: mean (SD) Education: mean (SD) Karnofsky: mean (SD) GSI: mean (SD) Intrusion: mean (SD) Avoidance: mean (SD)

␹2

All Participants N ⫽ 116

Intervention Group N ⫽ 63

Control Group N ⫽ 27

Refused to Participate N ⫽ 26

49 67

25 38

15 12

9 17

.253

NS

85 31

47 16

22 5

16 10

.245

NS

42 71

21 39

10 17

11 15

53.3 (15.46) 12.8 (4.45) 95.6 (7.72) 58.9 (10.40) 12.7 (4.45) 15.1 (5.46)

53.3 (15.51) 13.5 (4.41) 96.2 (7.53) 59.7 (9.43) 13.6 (5.22) 15.0 (5.28)

54.5 (14.23) 12.5 (3.12) 95.2 (7.53) 60.1 (12.01) 11.91 (4.18) 15.21 (5.15)

52.1 (16.99) 11.3 (5.41) 94.6 (8.11) 55.5 (10.38) 12.1 (5.17) 15.4 (7.05)

.813 F 0.168 2.320 0.430 1.77 1.47 0.019

P

NS P NS (.103) NS NS NS NS

NS, not significant; GSI, Global Severity Index.

3. Results Patients’ sociodemographic characteristics and psychological condition at T1 are recorded in Table 1. In general, their psychological distress (GSI) was mild, but fairly high scores were obtained for Intrusion and even higher scores for Avoidance. The mean scores of patients in the intervention, control and refusal groups were similar for all of the variables. The refusal group was excluded from any further analysis in this report. Table 2 presents the GSI and the Intrusion and Avoidance scores (mean values ⫾ S.D.) at the three assessment times for the cases that reached T3. Fifty-four of the 63 patients in the intervention group and 17 out of 27 in the control group reached T3. The difference in the dropout rate between the intervention group (14%) and the control group (37%) was significant (P⫽.02). The Table 2 Psychological condition by group at the three assessments

GSI T1 GSI T2 GSI T3 Intrusion T1 Intrusion T2 Intrusion T3 Avoidance T1 Avoidance T2 Avoidance T3

Intervention Group (N ⫽ 54)*

Control Group (N ⫽ 17)*

Mean

SD

Mean

SD

60.2 59.2 56.9 13.8 13.0 12.5 15.4 15.4 15.5

8.37 9.99 11.77 5.39 5.07 5.03 5.35 6.67 5.52

59.8 57.5 58.7 12.0 12.6 12.8 14.4 14.6 16.1

11.95 14.68 13.57 4.68 6.20 6.11 5.12 6.15 5.82

GSI, Global Severity Index. T1, First Assessment; T2, Second Assessment; T3, Third Assessment. * Includes only cases measured at the 3 assessment times.

19 dropouts were compared on all the variables to the 71 patients who reached T3. The only significant difference between these two subgroups was in their physical condition at T1; the 19 dropouts had a lower mean Karnofsky score of 91.5 ⫾ 9.6 compared to 97.0 ⫾ 6.6 in the other subgroup (P⫽.005). On the whole, the scores of the two groups on each of the three measures were quite similar. At T2, when the intervention was started, the scores in the control group were slightly but not significantly lower than those of the intervention group. Our primary objective was to determine whether the psychological intervention that started at T2 was still effective at T3, 6 months after the end of therapy. We used the differences in GSI, Intrusion and Avoidance, and in the nine BSI subscales between T2 and T3 as the dependent variables when assessing the efficacy of the intervention. Twelve separate Multiple Stepwise Regression Analyses were conducted— one for each dependent variable. Nine independent variables were included in each regression: gender, age, marital status, education, religiosity, Karnofsy score, cancer stage, intervention or control group, and the dependent variable level at T2. The results for the GSI score are summarized in Table 3. Of the 9 variables included in the regression, only 2 were found to be significantly related to the difference in the GSI level between T2 and T3. The higher the GSI level at T2, the greater the improvement at T3. Participation in the psychological intervention also had a substantial effect in decreasing GSI at T3. These 2 variables explained 22% of the variability in improvement in the GSI level. In 8 of the 9 BSI scales, the decrease (improvement) between T2 and T3 was greater in the treatment group. The probability of obtaining these results by chance is P⬍.02. When 9 separate Multiple Regressions were conducted for the BSI scales as dependent variables, only the differ-

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Table 3 Variables included in the equation by a Multiple Stepwise Regression with GSI difference between T2 and T3 as the dependent variable* Variable

Beta**

t

Sig***

Intervention Yes/No GSI at T2

⫺0.366

⫺2.90

0.005

0.288

2.28

0.027

* Independent variables included in the analysis were gender, age, marital status, education, religiosity, Karnofsy score, cancer stage, intervention or control group, GSI at T2. ** Standardized regression coefficients. *** All other independent variables were not significant.

ence between T2 and T3 in the Obsessive-Compulsive scale was found to be significantly related to group participation in the psychological intervention. In the treatment group, the improvement was higher. The differences between T2 and T3 on Intrusion and on Avoidance were each taken as a dependent variable in 2 separate Stepwise Multiple Regressions. Participation in the psychological intervention had no significant effect on the differences between T2 and T3 for Intrusion or for Avoidance. The only variables that were significantly related to the difference in Intrusion at T2 and T3 were the Intrusion level at T2 (the higher the level, the greater the difference) and the educational level (the higher the education, the greater the difference). Avoidance at T2 was the only variable that was significantly related to differences between Avoidance at T2 and T3 (the higher the Avoidance level at T2, the greater the difference).

4. Discussion The aim of this randomized study was to gather information about the long-term effects of a time-limited behavioral intervention on cancer patients. We studied consecutive patients who fulfilled our inclusion criteria and assessed their psychological distress as well as their coping abilities as measured by the BSI and the IES. Randomization took place 1 month after the cancer diagnosis. The group intervention was started only about 3 months after the diagnosis rather than immediately, because we wished to avoid the possible “contaminating” effect of the stress of cancer diagnosis and the assimilation and implications of this diagnosis for each patient. The main aim of the study was answered quite positively. The small positive effect of the behavioral intervention on psychological distress (GSI) was found to persist for at least 6 months after the end of the intervention. Although the effect at that time was not significant on measures of the IES, it was statistically significant according to the GSI. Reports in the literature are in general agreement that the BSI assesses psychological distress. It is not certain, however, whether the IES assesses coping mechanisms, aspects

of distress, or both [29], are assessed by the IES [30]. In the present study, the intervention had no significant effect on Intrusion or Avoidance, thus apparently supporting the opinion that the IES does assess coping. Accordingly, patients’ coping mechanisms would not be expected to change because of the type of intervention they received in this study. The rate of dropout from the study was much higher in the control group (37%) than in the intervention group (14%), possibly suggesting that the patients in the control group were expecting more than the usual standard care. Unexpectedly, the psychological distress (the mean psychological distress scores) of the intervention and the control groups at T3 was not significantly different. In a critical review of the literature on psychological intervention in cancer patients, Trijsburg et al. [31] noted the large differences in reported dropout rates. The dropout rate of 37% in this study is somewhat higher than that in most of the studies reviewed by Trijsburg et al. [31] and by Berglund et al. [32]. The fact that the patients in our study agreed to be assigned to the control group after being randomized might be linked to a possible cultural bias in a country such as Israel, where receiving psychotherapy still carries a stigma, especially among the medically ill. The method used in our study for randomization raises some ethical as well as methodological problems. Patients who are perceived not to be in distress and may not be in need of any psychological help—at least during the period of the study—are offered therapy. In our study, patients who refused the intervention were indeed found to be somewhat less distressed than those who agreed to participate. One possible way to deal with this problem might be to screen all new patients for psychological distress at a specific time after diagnosis and invite only distressed patients to participate. Among distressed patients there are certain to be those who will refuse to participate, and therefore they should be included in the analyses as a separate group [5,17,33,34]. One must also consider the question of whether it is logical and rational to offer a psychological stress-reduction intervention program to nondistressed patients. In an earlier study by our group, in which the positive effects of the intervention (six sessions of relaxation and guided imagery) were maintained by a large proportion of the participants for 6 months, it is possible that these encouraging results were achieved because the sample comprised self-selected, self-motivated, and highly distressed patients [35]. Our impression was that in a number of patients, despite their agreement to participate in the present psychological intervention, their self-motivation was not high. It is possible that this relative lack of motivation can account for the high rate of dropout. The results of a number of studies leave little doubt that psychological interventions are effective, at least in the short term, in decreasing psychological distress in cancer patients. We do not yet know, however, which treatment is best at each diagnostic stage of the illness. Additionally, in our intervention study, we did not measure the level of

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achieving relaxation. Therefore, we could not measure the amount of relaxation achieved for each patient and the direct influence in the GSI level. According to a report of the American Cancer Society, many well-controlled studies indicate that appropriately designed and supervised intervention groups can improve the quality of life of cancer patients. As a result, the Society “encourages them as a valuable and cost-effective component of comprehensive psychosocial services in cancer care” [36]. Taking into consideration both the positive outcome and the limitations of our study, we strongly recommend that studies of intervention should be prospective and longitudinal, and that the following possible limitations should be borne in mind: Y Refusal of patients who have entered the study to participate in any psychotherapy Y Dropout throughout the study Y Randomization to avoid the effects of sampling referral, self-referral and other biases. Further studies can be expected to provide meaningful information about the effectiveness of any individual or group psychological intervention and about the patient population that could derive the most benefit from different kinds of planned interventions. References [1] Redd WH. Behavioral intervention for cancer treatment side effects. Acta Oncol 1994;33:113–17. [2] Fawzy IF, Fawzy NW, Arndt LA, et al. Critical review of psychological interventions in cancer care. Arch Gen Psychiatry 1995;52: 100 –13. [3] Kogon M, Biswas A, Pearl D, et al. Effects of medical, and psychotherapeutic treatment of women with metastatic breast carcinoma. Cancer 1997;80:225–30. [4] Watson M. Psychosocial interventions with cancer patients: a review. Psychol Med 1983;13:839 – 46. [5] Meger L, Mark MM. Effects of psychosocial intervention with adult cancer patients: a meta-analysis of randomized experiments. Health Psychol 1995;14:101– 8. [6] Dow KH, Ferrell BR, Leigh SL, Gulasekaram P. An evaluation of the quality of life among long-term survivors of breast cancer. Breast Cancer Res Treat 1996;39:261–73. [7] House JS, Robbins C, Metzner HL. The association of social relationships with mortality. Am J Epidemiology 1982;116:123– 40. [8] Goodwin JS, Hunt WC, Key CR, Samet JM. The effect of marital status on stage, treatment and survival of cancer patients. JAMA 1987;258:3125–30. [9] Broadhead E, Kaplan BH. Social support and the cancer patient. Cancer 1991;67:794 –99. [10] Messeri P, Silverstein M, Litwak E. Choosing optimal support groups: a review and reformulation. J Health Soc Behav 1993;34: 122–37. [11] Courtens AM, Stevens FC, Crebolder HF, Philipsen H. Longitudinal study on quality of life and social support in cancer patients. Cancer Nurs 1996;19:162– 69.

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