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Pain Education for Underserved Minority Cancer Patients: A Randomized Controlled Trial

From the Department of Symptom Research, Division of Internal Medicine, Department of Breast Medical Oncology, Department of Bioimmunotherapy, The University of Texas M.D. Anderson Cancer Center, Houston; Hematology-Oncology Section, Department of Medicine, Baylor College of Medicine, Houston, TX; Duke Divinity School, Duke University, Durham, NC; Division of Hematology/Oncology, Sylvester Comprehensive Cancer Center, University of Miami School of Medicine, Miami, FL; and Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, WI

Address reprint requests to Karen O. Anderson, PhD, The University of Texas M.D. Anderson Cancer Center, Department of Symptom Research, 1100 Holcombe Blvd, Box 221, Houston, TX 77030; e-mail: koanderso{at}mdanderson.org

	ABSTRACT

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PURPOSE: Previous studies found that African American and Hispanic cancer patients are at risk for undertreatment of pain. We evaluated the efficacy of a pain education intervention for underserved minority patients.

PATIENTS AND METHODS: Ninety-seven underserved African American and Hispanic outpatients with cancer-related pain were enrolled onto a randomized clinical trial of pain management education. The patients in the education group received a culture-specific video and booklet on pain management. The control group received a video and booklet on nutrition. A research nurse met with each patient to review the materials. We measured changes in pain intensity and pain-related interference 2 to 10 weeks after the intervention, as well as changes in quality of life, perceived pain control, functional status, analgesics, and physician pain assessments.

RESULTS: Physicians underestimated baseline pain intensity and provided inadequate analgesics for more than 50% of the sample. Although the ratings for pain intensity and pain interference decreased over time for both groups, there was no statistically significant difference between groups. Pain education did not affect quality of life, perceived pain control, or functional status. African American patients in the education but not the control group reported a significant decrease in pain worst ratings from baseline to first follow-up (P < .01), although this decrease was not maintained at subsequent assessments.

CONCLUSION: Brief education had limited impact on pain outcomes for underserved minority patients, suggesting that more intensive education for patients and interventions for physicians are needed.

	INTRODUCTION

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Data from a large national study documented significant undertreatment of cancer-related pain.¹ Patients treated in minority settings were three times more likely to be undermedicated than patients seen in nonminority settings. In a follow-up study that examined African American and Hispanic outpatients with cancer,² 65% of the minority patients with pain did not receive the WHO-recommended analgesics, as compared with 50% of patients from nonminority settings. A subsequent study focused on the pain treatment of underserved Hispanic and African American patients.³ Although the majority of patients in this study received appropriate analgesics, 65% reported severe pain.

A number of patient-related barriers to the treatment of cancer pain in minority patients have been identified.^3-7 Studies that focused on the pain treatment of underserved Hispanic and African American patients revealed that patients in both ethnic groups expressed a belief in stoicism and concerns about possible addiction to opioid medications.^3,4 More than half of the patients also indicated some reluctance to complain about their pain to health care providers and questioned whether pain medications would be effective.

These studies of pain management barriers suggest that minority patients might benefit from education about pain management and how to discuss pain with their health care providers. Patients who expect pain relief, report pain, and are not reluctant to take analgesics should promote good pain management from their providers.⁸ In addition, social cognitive theory suggests that educational interventions need to be targeted for a specific ethnic group, given that pain-related attitudes vary across cultures.² Social cognitive theory also indicates that patients can benefit from observing credible role models of the appropriate behavior (ie, good pain control).⁹

A number of randomized clinical trials with largely nonminority, middle-class cancer patients experiencing pain have evaluated educational interventions.^8,10-17 Although the results were mixed, several of these trials reported significant reductions in pain ratings.^{8,11,12,15,17} The purpose of the current study was to evaluate the efficacy of a pain education intervention designed for underserved minority cancer patients. We hypothesized that patients presented with a package of educational materials on pain management would demonstrate greater pain reduction than a control group receiving pain treatment without the educational package.

	PATIENTS AND METHODS

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Setting and Patients
The randomized multisite clinical trial of pain management education was coordinated at The University of Texas M.D. Anderson Cancer Center. The patients were recruited in six outpatient oncology clinics between December 1998 and September 2002. Five of the clinics were in large public hospitals in Houston, TX; Miami, FL; and San Juan, Puerto Rico. The oncology clinics in these institutions provide medical care primarily to underserved minority patients. Patients were also recruited in the outpatient clinics of a tertiary care cancer center. The institutional review boards of each participating institution approved the study.

Eligible patients were required to (1) be an outpatient at the participating institutions, (2) be a member of a black/African American or Hispanic minority group, (3) have a socioeconomic disadvantage, as confirmed by a billing code indicating low-income status, (4) have a pathologic diagnosis of cancer, (5) have chronic cancer-related pain, (6) have a pain worst score on the Brief Pain Inventory (BPI) 4, (7) have had no major surgery within the past 30 days, (8) have an Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2, and (9) be 18 years of age or older. The bilingual research nurses who recruited patients received training in research issues related to underserved minority patients. If an eligible patient agreed to participate, the nurse obtained written informed consent and scheduled the time 1 assessment (T1), to be conducted in English or Spanish, depending on patient preference.

Figure 1 presents the flow of participants in the trial. Among the 304 eligible patients, 203 declined to participate because of lack of interest (28%), belief that the study would not be helpful (13%), having no time (10%), feeling too ill (6%), family or friend not wanting the patient to participate (5%), other reasons (10%), or no reason given (28%). Randomization of the remaining 97 patients was stratified by study site and minority group. Failure to complete the study was related to death (31%), being too ill (22%), referral to hospice (8%), moving away (8%), or not returning to the clinic (31%).

View larger version (41K): [in this window] [in a new window]   Fig 1. Flow of participants in the trial. T2, patient’s first follow-up assessment at time 2 (week 2 to 4); T3, second follow-up assessment at time 3 (week 6 to 7); T4, third follow-up assessment at time 4 (week 8 to 10).

A research nurse met with each patient, and a family member or caregiver if possible, for approximately 30 minutes after the video to answer questions and to emphasize to the patient the importance of reporting pain to the health care team. The nurse also called the patient within 48 to 72 hours of the clinic visit to review the patient's pain control.

The control group received a nutrition education package, available in English and Spanish, that was designed to control for the effects of education and time spent with the research nurse. The nutrition package consisted of a videotape developed at Fred Hutchinson Cancer Research Center and written materials on nutrition for the cancer patient. A research nurse met with each patient, and a family member or caregiver if possible, for approximately 30 minutes after the video to answer questions and to emphasize to the patient the importance of good nutrition for cancer patients. The nurse also called the patient within 48 to 72 hours of the clinic visit to review the patient's nutritional status.

Outcome Measures
All patients received the pain management interventions usually given by the clinic staff. The primary outcome measures were changes in pain intensity and pain-related interference assessed at the first follow-up at time 2 (T2, week 2 to 4). The assessment periods included ranges of times to coordinate with patient clinic visits. Secondary outcome measures included functional status, quality of life, perceived control of pain, and adherence to analgesic prescriptions. The patients' physicians also provided their assessments of the patients' pain. The primary and secondary outcome measures also were assessed at the second follow-up at time 3 (T3, week 6 to 7) and the third follow-up at time 4 (T4, week 8 to 10) to determine the sustainability of any treatment effects.

Pain and pain-related interference were assessed using the BPI.¹⁸ The BPI asks patients to rate their pain intensity and how much their pain interferes with several quality-of-life domains. Issues of validity and reliability of the English and Spanish versions of the BPI have been examined in detail.^18,19

Quality of life was measured by the Physical and Mental Health Summary Scales of the Short Form (SF) -12 Health Survey.^20,21 The United States–Spanish version of the SF-12 Health Survey was developed to be acceptable to all Spanish-speaking people throughout the United States.

The Pain Control Scale of the Survey of Pain Attitudes was used as a measure of the patients' perceived control over their pain.^22-24 The scale was translated into Spanish and back-translated by professional bilingual translators.

Each patient's oncologist was asked to complete the Physician Pain Assessment Survey after the patient's clinic visit.^1,2 This instrument asks the physician to rate the patient's worst pain during the past week. Because poor pain assessment has been identified as a factor in inadequate pain management,¹ the degree of concordance between physician and patient was indexed by the discrepancy between the physician's and patient's ratings of the patient's pain. The physicians were blind to the patients' group assignments.

The research nurse recorded the patient's current analgesic medications and adherence to the prescribed analgesics and assessed the patient's ECOG performance status.²⁵ The analgesic data were used to estimate the adequacy of analgesic prescription by computing a Pain Management Index (PMI) for each patient.^1,2 The PMI is based on guidelines for treating cancer pain from the WHO^26,27 and the Agency for Health Care Policy and Research.²⁸ The PMI provides a comparison of the most potent analgesic prescribed for a patient relative to the level of that patient's reported pain. To determine the PMI, the most potent analgesic prescribed is classified as one of four levels, and the patient's pain worst score from the BPI is classified as mild, moderate, or severe. The PMI is computed by subtracting the pain level from the analgesic level.

Statistical Analysis
The primary outcome variable was change in pain worst ratings. The pooled standard deviation of 2.3 used in the sample-size calculations was estimated from our previous research.^3,4 The sample size was calculated to detect a difference of 1.3 in the mean reductions in the pain worst ratings between the education and control groups with 80% power. To detect this difference, with P < .05 (two-tailed test), at least 49 patients had to be enrolled in each group.

The Fisher's exact test and unpaired t tests were used to compare differences between the education and control groups on demographic, disease, and pain-related variables at baseline. Repeated measures analyses of variance on the outcome measures were used to compare the education and control groups over time. To determine whether the two groups differed across time, we examined the group-by-time interaction. To test for treatment effects, we compared change scores from T1 to T2 between the education and control groups. To test for the sustainability of the treatment effects, we compared change scores from T1 to T3 between the two groups. The analyses also were performed separately for Hispanics and African Americans. In addition, two separate analyses were performed on the outcome variables: an intent-to-treat analysis (ITT) that included all randomized participants and an analysis that included only patients who completed the study. Missing ITT values were imputed by last observation carried forward. The patients who completed no follow-up assessments were assumed to remain at baseline values.

	RESULTS

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Patient Characteristics
Table 1 shows that the education and control group patients were comparable with regard to demographic and disease-related variables. Most of the patients in the education (68%) and control (72%) groups reported severe pain intensity ( 7 on the BPI scale).²⁹ The control group tended to have more patients (72%) with good ECOG performance status than the education (56%) group (P = .12).

View larger version (14K): [in this window] [in a new window]   Fig 2. Mean pain severity over time for education and control groups by analytic method (complete case analysis [CC] v intent-to-treat analysis [ITT]). T1, patient's initial assessment at time 1; T2, first follow-up assessment at time 2 (week 2 to 4); T3, second follow-up assessment at time 3 (week 6 to 7); T4, third follow-up assessment at time 4 (week 8 to 10).

For the African American patients, the CC analysis of the pain worst item revealed a significant effect for time (P < .04) and a significant group-by-time interaction (P < .01). Figure 3 demonstrates that African American patients in the education group reported a significant decrease in pain worst ratings from baseline to T2. In contrast, the mean pain worst ratings of the control group did not change significantly from T1 to T2. The change in pain worst ratings from baseline to T2 for the education group is significantly larger than the change in pain worst ratings from baseline to T2 for the control group (P < .05). The effect of the pain education intervention was not maintained, however. By the T4 assessment, the mean pain worst rating of the education group had increased significantly, as compared with T2 (P < .004).

View larger version (15K): [in this window] [in a new window]   Fig 3. Mean pain severity over time for African American (AA) and Hispanic patients in the education and control groups. T1, patient's initial assessment at time 1; T2, first follow-up assessment at time 2 (week 2 to 4); T3, second follow-up assessment at time 3 (week 6 to 7); T4, third follow-up assessment at time 4 (week 8 to 10).

A mean BPI pain interference score was calculated as the mean of the BPI interference items. The CC repeated-measures analyses of variance on the pain interference score revealed a significant group-by-time interaction for the African American patients (P < .04) but not for Hispanic patients (P < .41). Figure 4 shows that for African Americans, the significant group-by-time interaction is derived from significant differences between the education and control groups in their change scores from T2 to T4. Because there is no significant group-by-time interaction for the Hispanic patients, none of the change scores are significantly different between the education and control groups.

View larger version (15K): [in this window] [in a new window]   Fig 4. Mean pain interference over time for African American (AA) and Hispanic patients in the education and control groups. T1, patient's initial assessment at time 1; T2, first follow-up assessment at time 2 (week 2 to 4); T3, second follow-up assessment at time 3 (week 6 to 7); T4, third follow-up assessment at time 4 (week 8 to 10).

	DISCUSSION

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The educational intervention was designed to encourage patients to report their pain to their physicians. The first follow-up assessment at weeks 2 to 4 allowed enough time for analgesic medication changes that might impact pain outcomes. The physicians' estimations of the education group patients' pain improved significantly from baseline to the first follow-up assessment. No improvement was seen for the physicians' estimations of the control group patients' pain. The improvement for the physicians treating the education group suggests that patients who received the educational intervention did communicate with their doctors more effectively about their pain. Unfortunately, the improvement in physician pain estimations for the education group was not maintained at the subsequent assessments.

The limited efficacy of the pain education intervention may be due to several factors. First, our sample size may not have been large enough to detect an effect of the educational intervention. Second, the physicians and nurses at the study sites were aware that our research team was assessing pain. Although the staff did not know the patients' group assignments, they did know which patients were enrolled onto the study. Thus the physicians may have improved their pain treatment because of the attention generated by the research. The decreases in mean pain intensity demonstrated by both the education and control groups at the first follow-up is consistent with this explanation. In addition, patients in both groups were aware that they were enrolled in a pain study. The focus on pain may have encouraged patients in both groups to discuss pain with their physicians. Also, for ethical reasons, our research nurses encouraged patients in both groups to report severe pain and any difficulties with pain medications. The effects of attention on pain and encouragement to report pain may have obscured the possible effects of education.

The educational intervention was designed for a rapid impact, given that the patients typically were very ill with advanced disease. More intensive education, however, may be needed to impact pain outcomes for underserved minority patients. Unfortunately, lengthy or individualized education is not always feasible in a busy oncology clinic at an understaffed public hospital. Our videotapes and booklets were designed to be practical and cost effective and addressed the most common barriers to pain treatment among underserved minority patients. A recent study of cancer pain education in a sample of largely nonminority middle-class patients found that an individualized approach that targeted a patient's specific beliefs produced decreased pain intensity at an 8-week follow-up.¹⁵ Research with underserved minority and nonminority patients is needed to determine whether intensive or individualized education can improve pain treatment outcomes for underserved patients.

The educational level of the patients is another variable that may have limited the impact of pain education. Educational interventions on cancer pain may be more effective for individuals with higher levels of education.¹⁵ Although our educational materials were targeted for a fifth-grade reading level, the materials may have been difficult for some patients to comprehend. A related limitation of our study was the absence of an outcome measure of cancer pain knowledge and beliefs, so that we could not determine whether the education group patients learned more pain-related information than the control group patients. The possibility that knowledge gain was minimal is suggested by the fact that the patients in both the education and control groups reported perceptions of minimal control over their pain that did not change significantly.

In the present study, most of the patients in the education and control groups had advanced disease and were often referred to hospice by the end of the study. The increases in pain typically associated with disease progression may have limited the impact of education. Approximately one third of the patients had dropped out of the study by the fourth assessment. Although the remaining patients in the education and control groups did not differ with regard to functional status, it is possible that the groups differed significantly on medical variables that impacted their pain levels. At the fourth assessment, the control group reported lower levels of pain than the education group. The reason for this difference is not clear but may be related to physician underestimation of the pain of education-group patients at the third assessment.

Recruitment of medically underserved Hispanic and African American patients was challenging. Our bilingual research nurses were trained in culturally sensitive recruitment strategies and had the same ethnicity as the patients. The attending oncologists supported the study, and the patient's spouse or significant other typically was present when the study was explained to the patients. Despite these recruiting strategies, about two thirds of the eligible patients declined participation. The concept of education on cancer pain and its treatment was not appealing to many patients. Future studies with underserved minority patients should include focus groups or surveys of the target population to be certain that the proposed intervention is perceived as potentially beneficial.

Our results indicate that short-term education alone is not sufficient to improve pain management for underserved minority cancer patients. A comprehensive pain intervention that involves both physicians and patients is probably needed. For example, more intensive individualized education for patients could be combined with the provision of clinical practice guidelines for pain treatment to physicians.³⁰ Future studies should evaluate the efficacy of multicomponent programs that include an intervention for physicians and targeted education for underserved minority cancer patients with pain.

	Authors' Disclosures of Potential Conflicts of Interest

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The authors indicated no potential conflicts of interest.

	Acknowledgment

 
We thank the medical, nursing, and administrative staff at each of the study sites, with special thanks to Luis Baez, MD, Misha-Miroslav Backonja, MD, Josie Betancourt, Cynthia DeLeon, Philomena Doliny, Marilyn Morrissey, Maria Sanchez, Karen Syrjala, PhD, and Patricia Washington, DSN. We also thank Jeanie Woodruff for excellent editorial assistance.

	NOTES

 
Supported by the United States Army Medical Research and Materiel Command under DAMD17-94-J-4233 and by Public Health Service grant Nos. CA26582, CA64766, and CA85228 from the National Cancer Institute.

Presented in part at the 22nd Annual Scientific Meeting of the American Pain Society, March 20-23, 2003.

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

 
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Submitted June 24, 2003; accepted September 23, 2004.

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This Article Abstract Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Anderson, K. O. Articles by Cleeland, C. S. Search for Related Content PubMed PubMed Citation Articles by Anderson, K. O. Articles by Cleeland, C. S. Social Bookmarking                            What's this?