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Journal of Clinical Oncology, Vol 22, No 9 (May 1), 2004: pp. 1736-1742
© 2004 American Society of Clinical Oncology.
DOI: 10.1200/JCO.2004.04.138

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Individuals With an Increased Risk of Colorectal Cancer: Perceived Benefits and Psychological Aspects of Surveillance by Means of Regular Colonoscopies

A. Liljegren, G. Lindgren, Y. Brandberg, S. Rotstein, B. Nilsson, T. Hatschek, E. Jaramillo, A. Lindblom

From the Departments of Clinical Genetics, Oncology and Pathology-Radiumhemmet and the Department of Gastroenterology, Karolinska University Hospital, Karolinska Institute; and The Oncology Unit of Radiumhemmet at Danderyds Hospital, Stockholm, Sweden

Address reprint requests to Annelie Liljegren, MD, PhD, Department of Clinical Oncology, Danderyds Hospital, 182 88 Stockholm, Sweden; e-mail: annelie.liljegren{at}telia.com


    ABSTRACT
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
PURPOSE: To evaluate the psychological consequences of genetic counseling followed by a surveillance program using colonoscopy among individuals with increased risk of colorectal cancer.

PATIENTS AND METHODS: Two hundred sixty-five individuals, participating in a surveillance program with colonoscopy, were mailed a survey questionnaire that assessed their experience of the surveillance program and their perception of the risk of colorectal cancer. The Hospital Anxiety and Depression scale and the Swedish Short Form-36 Health Survey was also included.

RESULTS: Two hundred forty individuals completed the questionnaire and were divided into the following risk groups: risk group 1, an individual with a mutation in hMLH1 or hMSH2 and a lifetime colorectal cancer risk of 80% (n = 28); risk group 2, a lifetime colorectal cancer risk of 40% (n = 129); and risk group 3, a lifetime colorectal cancer risk of 20% (n = 83). Among all individuals, the mean for perceived benefit was 8.0, and the perception of discomfort was 3.3 on the visual analog scale (1-10). In risk group 1, 61% underestimated personal risks as being 40% or less. Approximately 50% of the subjects in risk groups 2 and 3 either under- or overestimated their lifetime risk. According to the Swedish Short Form-36 Health Survey and the Hospital Anxiety and Depression scale, the study sample resembled the reference population.

CONCLUSION: A majority of the study sample understood why they were under surveillance, and regular colonoscopies were well-tolerated. The wide range of risk perception as well as low-risk perception in mutation positive subjects is acceptable, as long as these individuals adhere to surveillance programs and do not demonstrate increased levels of anxiety or depression.


    INTRODUCTION
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
The number of individuals participating in cancer prevention programs is increasing and includes healthy high-risk individuals. These prevention programs often include genetic counseling and when possible, predictive genetic testing. Regular colonoscopies are provided for high-risk individuals and have resulted in decreased incidence of, and mortality from, colorectal cancer.1 Awareness of increased risk of colorectal cancer through risk estimates, knowledge of positive mutation status, and participation in surveillance programs could cause physical and psychological distress. Misunderstanding of risk estimates and increased psychological distress may lead to a less strict adherence to surveillance. It is therefore of major importance to evaluate psychological aspects related to genetic counseling and the influence of a surveillance program in at-risk individuals. Such studies have been conducted on women tested for breast-ovarian cancer genes.2,3 Few studies have reported psychological reactions in connection with familial colorectal cancer.4 Recently, studies have been published investigating the psychological impact and psychosocial influences of colorectal screening in older adults in the general population.5,6 The aim of the present study is to elucidate, by means of a cross-sectional study, how individuals with increased risk of colorectal cancer experience participating in a surveillance program with regular colonoscopies. The following issues were studied: perception of benefits of prevention, perception of discomfort associated with colonoscopies, risk perception, health-related quality of life and level of anxiety and depression, and knowledge of why surveillance with colonoscopies has been recommended.


    PATIENTS AND METHODS
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
Subjects and Procedures
Over a 10-year period (January 1990 to July 1999), 304 individuals with increased risk of colorectal cancer were referred to the Family Cancer Clinic at Karolinska University Hospital (Stockholm, Sweden). Genetic counseling and regular colonoscopies were offered to these patients. The subjects in families who fulfilled the Amsterdam criteria I7 were offered genetic testing, when possible, from 1994 onwards. All individuals received oral and written information about the genetic findings, the risk of harboring a mutation in one of the mismatch repair genes, hMLH18 or hMSH2,9 and the estimated risk for disease in mutation positive carriers. In families not fulfilling the Amsterdam criteria I,7 the individuals were informed about their lifetime risk of colorectal cancer according to empirical studies.10,11 Subjects with an increased lifetime risk of more than 10% were offered regular colonoscopies (every 2-3 years depending on lifetime risk of colorectal cancer), and before inclusion in the surveillance program they were verbally informed about the colonoscopy procedures and the reason for colonoscopy. They were told that cancer development in the colon is initiated in a polyp and that the risk of developing colorectal cancer is substantially reduced by removing all polyps.

Three hundred four at-risk individuals, described in detail12, who took part in the surveillance program were eligible for the present study. Twenty-three individuals who were tested mutation negative at some time during the surveillance period were excluded, because their lifetime risk of colorectal cancer was the same as for the general population after the test. Sixteen individuals were excluded, as their present address was not found. Thus, 265 eligible patients were sent a questionnaire by mail in November 1999. By filling in the questionnaire, the individuals gave their informed consent to participate in the study. Two reminders were sent in January and February 2000 to those participants who failed to return the questionnaire. The present study was considered to be a quality assurance project by the ethics committee at the Karolinska Institute.

Family Types, Diagnoses, Genetic Background, and Risk Groups
Our study sample was classified in three groups according to their estimated lifetime risk for colorectal cancer. Risk group 1 included subjects classified as hereditary nonpolyposis colorectal cancer (HNPCC),13 harboring a mutation in one of the mismatch repair genes8,9 with an 80% lifetime risk of colorectal cancer, and for women with a 60% lifetime risk of endometrial cancer.14

Risk group 2 was defined as an individual with a lifetime risk of colorectal cancer of 40%. Individuals from HNPCC with unknown mutation status, and individuals with hereditary colorectal cancer (HCRC)12,15 with three or more relatives with colorectal cancer but not fulfilling the Amsterdam criteria I,7 were included in risk group 2. Individuals from the HCRC group were likely to segregate unknown predisposing gene mutations and with approximately the same risk of developing colorectal cancer as untested individuals with HNPCC.10,11 Risk group 3 consisted of individuals with a lifetime risk of colorectal cancer of 10% to 20%. These individuals had two close relatives affected by colorectal cancer,12,15 with risk estimates based on empirical data.10,11 Grandchildren of affected individuals in HNPCC and HCRC were also included in this group.

Colonoscopies
Colonoscopy was carried out using a conventional video-colonoscope. Patients received intravenous diazepam (0-10 mg) and/or ketobemidone (0-5 mg) depending on their initial request or as indicated by the patient's discomfort. All polyps were either biopsied or removed endoscopically.

Questionnaire About Experience of Surveillance and Colonoscopy
A questionnaire including multiple-choice (ie, yes/no/don't know) and scaled responses was designed. The questionnaire included one question about perceived risk of developing colorectal cancer ("What lifetime risk do you perceive for developing colorectal cancer?"). A categoric response scale was provided: 100%, 80%, 40%, 20%, 10%, 5%, and 1%.

Two open questions were asked: "Why have you been offered regular colonoscopies?" and "Explain, if you can, why polyps are removed from the colon," in order to evaluate the level of knowledge about the reason for surveillance and polypectomy. To increase an objective evaluation of the open answers, two oncologists with special interest in hereditary issues were asked to review the responses.

In addition, the questionnaire included one section with seven questions (Table 1) estimating perceived benefit and discomfort associated with the colonoscopic examination. Each question was followed by a straight line with a 10 cm continuous visual analog scale (VAS). The VAS ranged from 0, not painful at all or not worried at all, to 10, extremely painful or extremely worried. The VAS has been widely used in evaluating pain.16 Subjective feeling has been measured with the VAS in psychological studies17 and also recently to evaluate discomfort during colonoscopy.18 Cutoff points for the VAS in respect to pain have been established, and Collins et al19 conclude that values more than 3 cm reflects moderate pain and 5.4 cm reflects severe pain. Cutoff points for symptoms that reduce quality of life symptoms have been established by Grunberg et al20 as follows: mild, 2.4 cm; moderate, 4.3; and severe, 8.4. Thus, in our study, we consider a value of 3 cm or less to show that the procedure is well accepted. In terms of perception of benefit of colonoscopy, a value between 7 and 10 is assessed as more than average perception of benefit, and we suggested that this value would be interpreted as a large benefit.


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Table 1. Questions Concerning Experience of Colonoscopies

 
The Hospital Anxiety and Depression (HAD) Scale
The HAD scale is a self-assessment scale originally designed to detect anxiety and depression in somatically ill patients.21 The HAD scale contains 14 questions: seven questions reflect anxiety and seven reflect depression. The response alternatives indicate the intensity of the given mood. There are four response alternatives for each item (scored from 0 to 3). The sum on each subscale indicates the overall anxiety and depression score (minimum, 0; maximum, 21). The original authors21 categorized a score of 8 or more as anxiety (or depression) of probable significance and a score of 11 as clinical cases. The HAD scale appears to be a reliable and valid method for measuring emotional distress in medical patients,22 and in a recent review,23 the validity of the HAD-scale in patients from nonpsychiatric hospital clinics was confirmed. The HAD scale has been evaluated in two Swedish reference samples.24,25 Several international studies using the scale have found that men score lower values on both subscales than women.2628 The results from the Swedish study by Lisspers et al25 were used as a reference sample to compare the HAD values in the study sample. Although the response rate was low in the Lisspers et al study,25 we used this as a reference study because the cohort was considerably larger than the Sullivan et al study.24

Health-Related Quality of Life (Short Form-36)
The Swedish Short-Form-36 Health Survey (SF-36) was used to assess the individuals' health related quality of life.2931 The SF-36 was established as an improved short form survey of the Medical Outcome Study, a 20 item short-form health survey which was used in a large health service research study 15 years ago.32 The SF-36 consists of 36 items measuring eight health domains. The scale ranges from a minimum of 0 to a maximum of 100. In our study, five domains were analyzed: general health, role-emotional, vitality, social functioning, and mental health. Physical functioning, role-physical, and bodily pain were excluded because no physical effects were expected in connection with the surveillance program. The psychometric properties of the Swedish version of the SF-36 have been described and normative values from the general Swedish population have been published.31

Statistical Analyses
All data analyses were performed with the SPSS Version 11.0 for Windows (SPSS, Inc, Chicago, IL). Group differences regarding the benefit and discomfort of colonoscopies were performed by multivariate analysis. The question analyzing risk perception for the lifetime risk of colorectal cancer was analyzed using three groups: 1) 100% and 80% as high risk; 2) 40% as intermediate risk; and 3) 20%, 10%, 5%, and 1% as low risk.

Unpaired t-tests were used to analyze differences between the study group and the general population regarding SF-36 and HAD values. As a result of multiple comparisons, a P value of P = .05 may not be significant.


    RESULTS
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
Study Sample
Of the eligible subjects (n = 265), 91% completed the questionnaire with usable data. Four percent returned the questionnaire without answering the questions and 5% did not return the questionnaire. The study sample consisted of 240 subjects (mean age, 48 years). All basic demographic information was self reported and summarized in Table 2.


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Table 2. Baseline Demographic Variables of the Patients (self reported)

 
Benefit of Colonoscopies
Among all individuals, the mean for perceived benefit was 8.0 (standard deviation [SD], 1.5; data not shown) on the VAS with a range of 0 to 10 (0, no benefit at all, to 10, great benefit). Seventy-five percent of the individuals accurately remembered previous polypectomies, while 7% had an incorrect recollection, and 18% did not provide an answer to this question. Individuals who recalled polypectomy had a significantly higher perception of benefit—8.5 on the VAS—as compared with the individuals who did not recall a polypectomy (VAS, 7.7; P < .001). There were no statistically significant differences in perceived benefit with respect to risk group, age, sex, or number of colonoscopies (data not shown).

Discomfort From Colonoscopies
The mean and SD values concerning experiences of colonoscopies are presented in Table 1. The perception of discomfort (the mean of the total score of the seven questions) in the study sample was 3.3 (SD, 1.4) on the VAS (Table 3). Increasing age (P = .001) and a longer surveillance (increased number of colonoscopies; P = .013) were significantly and positively associated with less discomfort (Table 3).


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Table 3. Multivariate Analysis of Variance With Respect to Mean Values of Discomfort (n = 185)

 
Perception of Risk
The risk perception of lifetime risk of colorectal cancer in the study sample is presented in Figure 1. Among the 28 mutation-positive subjects (risk group 1), 17 subjects (61%) reported their personal risk as being 40% or less, and 36% perceived a 1% to 20% lifetime risk of colorectal cancer. In risk groups 2 and 3 (129 and 83 individuals, respectively), approximately 50% of the subjects, either under- or overestimated their personal lifetime risk of colorectal cancer (Fig 1).



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Fig 1. Perceived risk of lifetime risk of colorectal cancer in the study sample. The white bar indicates perceived risk of 80%; the black bar indicates perceived risk of 40%; and the gray and white bar indicates perceived risk of 1% to 20%.

 
HAD Anxiety and Depression
All HAD anxiety and depression values were within the normative data range (Table 4). The study sample (age, 30 to 59 years) had statistically significant lower values regarding depression (less signs of depression) than the reference population.25 Males scored higher values with regard to anxiety as compared with the reference population (P = .013; data not shown). Positive mutation carriers had the lowest values for both anxiety and depression (data not shown).


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Table 4. HAD Mean Scores Compared to General Population

 
Quality of Life: SF-36
The study sample showed statistically significant lower values regarding mental health (P = .013) and vitality (P = .016; Table 5) as compared with the reference population.31 There were also sex differences in these two domains with lower scores for vitality (P = .048) among women and lower scores for mental health among men (P = .047; data not shown).


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Table 5. SF-36 Mean Scores Compared to General Population

 
High Level of Knowledge Concerning Reason for Surveillance
Eighty-eight percent (n = 211) of the subjects gave a correct answer to the question, "Why have you been offered regular colonoscopies?" Four percent of the individuals gave an incorrect answer. Ten individuals (4%) responded that research was the reason for their colonoscopies. The second question, "Explain, if you can, why polyps are removed from the colon?" was answered as follows: 84% (n = 201) of the individuals gave a correct answer, 6% of the individuals responded incorrectly, and 10% did not provide an answer.


    DISCUSSION
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
The most important issues for this population at increased risk for colorectal cancer is optimal adherence to surveillance and the awareness that prevention programs do not cause increased levels of anxiety or depression. As all individuals had different follow-up periods, and the time since the most recent colonoscopy varied between the subjects, this may have resulted in recall bias. However, this type of study displays a mean cross-sectional analysis of how individuals undergoing regular colonoscopies perceive the benefits and discomfort. The majority of the study sample reported their experience of the surveillance and colonoscopies as beneficial and that the level of discomfort from the colonoscopies was low. A lower level of depression was found as compared with a reference study.25 An increased number of colonoscopies resulted in lower values of discomfort but did not affect the values of benefit. Individuals who recalled earlier polypectomies even reported improved perception benefit. These results imply that the detection of polyps may increase the experience of benefit and that most individuals experience less discomfort the longer they have participated in the program. It is also possible that individuals who have been part of the program for a few years feel gratefulness toward the prevention program and this might have caused bias regarding both discomfort and benefit values. Using pain during colonoscopy as reference, the mean Pearson correlation between this question and the other questions was 0.41, which indicates a moderate internal consistency between the questions. The considered factors in Table 3 reflect different aspects of discomfort. The factors should, however, be interpreted with caution. Our results are consistent with another study also using the VAS in evaluating discomfort and pain during and 2 weeks after the colonoscopy for diagnostic reasons. In this study, the young (20-40 years of age) experienced more discomfort than older individuals and females experienced more discomfort than males.18 Various studies have demonstrated high validity using the VAS in measurement of subjective phenomena as global vigor and affect33 and quality of life.34 The reliability of the VAS has been evaluated in several studies35,36 but needs to be validated for experiences of colonoscopy in further studies.

Risk perception is a complex issue and finding the correct response format is difficult. If high-risk individuals underestimate their personal cancer risk, there is a danger of less participation in recommended surveillance programs. A majority of the mutation carriers underestimated their personal cancer risk. These results are in accordance with another study,37 where only 35% of the mutation-positive subjects reported a correct personal cancer risk 1 year after the testing procedure. One explanation for this phenomenon could be denial as a protective coping mechanism. It is also possible that the lower perceived risk reported by the mutation carriers was influenced by the fact that they were under surveillance and undergoing regular colonoscopies. Among mutation carriers with lower risk perception (n = 17), five individuals had a history of polypectomy, which was recalled correctly, two individuals recalled incorrectly no history of polypectomy, and ten mutation carriers with lower risk perception correctly recalled no history of polypectomy. Consequently, the lower risk perception could be influenced by the fact that they were under surveillance and/or had a relatively low number of removed colon polyps. Thus, their risk estimates, as long as they participated in surveillance programs, were justifiably lower. In the other two risk groups, the risk estimates were more variable. In risk group 2, half of the individuals reported correct risk estimates, while 25% underestimated and 25% overestimated their risk. In risk group 3, most individuals overestimated their risk of colorectal cancer. In fact, 20% of the low-risk individuals believed their lifetime risk of colorectal cancer to be 80% (Fig 1). One possible explanation could be that the findings of colon polyps during surveillance could lead to an increased risk perception in low-risk individuals. The information given to mutation carriers is precise in terms of an 80% lifetime risk. In the other two risk groups, the information is more complex, and thus, more likely to be subject to personal interpretation. The finding of overestimation of risk in risk groups 2 and 3 is in accordance with the observation by Collins et al,4 who found worry to be a motivating factor for attendance, and consequently, these individuals could be expected to report a higher lifetime risk of colorectal cancer.

The adherence to surveillance is important in this population and is facilitated if individuals at risk are well aware of the reason for the prevention procedure, although their risk perception might still be incorrect. Our study sample showed a good level of knowledge about the reason for and benefit of regular colonoscopies.

Two well-validated, widely used scales, SF-36 and HAD, were used in our study. The levels of anxiety and depression were, in general, within the normative data range (Tables 4 and 5). The number of individuals with increased levels of anxiety and depression was small, which is in accordance with another study.38 Interestingly, the men scored higher than the women on HAD anxiety (mean, 5.5 v 4.7; P = .313) and HAD depression, (P = .035; data not shown) which contrasts with other studies using this scale, which reported that men scored lower than women.2628 In addition, this trend was also seen in the SF-36 results, where men's values were lower regarding mental health as compared with the general population (data not shown). Males who request genetic counseling and testing and who attend surveillance programs may have more concerns about their lifetime risk of colorectal cancer as compared with females in the same situation. In our study, more women attended the clinic for counseling. This phenomenon was also found in Collins' study,4 and it is possible that men who actually ask for counseling could have a higher level of anxiety than females in a risk population.

In conclusion, a majority of the individuals in this study sample understood why they were under surveillance, and the regular colonoscopies were well accepted. The wide range of risk perception as well as the surprisingly low-risk perception in mutation-positive subjects is acceptable as long as these individuals participate in surveillance programs and do not demonstrate increased levels of anxiety or depression.


    Authors' Disclosures of Potential Conflicts of Interest
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
The authors indicated no potential conflicts of interest.


    Acknowledgment
 
The authors wish to express their sincere gratitude to Ulla Platten for valuable assistance in this work.


    NOTES
 
This work has been supported by grants from The Swedish Cancer Society, the Karolinska Institute, and The King Gustav V Jubilee Foundation.

This paper was presented at the 39th Annual Meeting of the American Society of Clinical Oncology, Chicago, IL, May 29-June 1, 2003 (poster # 369).

Authors' disclosures of potential conflicts of interest are found at the end of this article.


    REFERENCES
 TOP
 ABSTRACT
 INTRODUCTION
 PATIENTS AND METHODS
 RESULTS
 DISCUSSION
 Authors' Disclosures of...
 REFERENCES
 
1. Järvinen HJ, Aarnio M, Mustonen H, et al: Controlled 15-year trial on screening for colorectal cancer in families with hereditary nonpolyposis colorectal cancer. Gastroenterology 118:829–834, 2000[CrossRef][Medline]

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3. Meiser B, Halliday JL: What is the impact of genetic counselling in women at increased risk of developing hereditary breast cancer? A meta-analytic review. Soc Sci Med 54:1463–1470, 2002

4. Collins V, Halliday J, Warren R, et al: Cancer worries, risk perceptions and associations with interest in DNA testing and clinic satisfaction in a familial colorectal cancer clinic. Clin Genet 58:460–468, 2000[CrossRef][Medline]

5. Wardle J, Sutton S, Williamson S, et al: Psychosocial influences on older adults' interest in participating in bowel cancer screening. Prev Med 31:323–334, 2000[CrossRef][Medline]

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29. Sullivan M, Karlsson J, Ware JE, Jr: The Swedish SF-36 Health Survey–I. Evaluation of data quality, scaling assumptions, reliability and construct validity across general populations in Sweden. Soc Sci Med 41:1349–1358, 1995

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Submitted April 21, 2003; accepted February 20, 2004.


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Copyright © 2004 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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