Racial Differences in Adherence to Prescribed Analgesia in Cancer Patients: An Integrated Review of Quantitative Research
Another study with a primarily African-American cohort did not use the BQ-II but asked specific questions in regards to perceived barriers to analgesics. Within the cohort, 87% reported a fear of addiction to pain medicine. Further, 77% had a fear of injection, 75% were concerned about a tolerance for analgesics, and side effects were a major concern. Overall, nausea was the greatest reported concern followed by potential for confusion, which was negatively associated with taking analgesics. Distracting the doctor from curing their illness was a predictor of improved adherence; however, individuals were more likely to take Tylenol for pain relief. Similarly, no significant barrier items affected adherence to NSAIDs. In relation to step 2 opioids, patients who felt it was important to be strong by not talking about pain were more likely to have better adherence [4]. Similar results with African Americans were identified in another study [13]. In the comparison between African Americans and whites, African Americans had more subjective barriers compared to whites. Particularly for African Americans, each unit increase in concern about distracting the doctor from curing the disease, the percentage of dose adherence decreased by 7.44 [13].
In a study that compared payer groups, a questionnaire elicited reasons for nonadherence [3]. Similar reasons for nonadherence emerged including financial, fear of addiction or increased medication use, and running out medication.
Behavioral History
Only 1 study used CAGE (Cut down, Annoyed, Guilty, and Eye-opener), an alcohol-screening questionnaire, to determine a possible relationship with analgesic adherence. In this study, there were 19 cases of opioid deviation, 16% of which were CAGE positive and had severe deviation toward less than the prescribed doses [12]. In further analysis, no association was found between CAGE positively and opioid deviation to higher intake [12]. Two other studies gathered data on history of depression, substance use, and alcohol use but no significant correlation was found [3,13].
,Discussion
Previous literature has reported overall analgesic adherence rates among oncology patients ranging from 62% to 72% [23]. Factors at the provider and system level have been considered in past research, but the patient perspective is poorly represented in the literature [13]. A majority of studies on analgesic adherence have been completed with cohorts made up predominantly of white individuals [13,23,24], while others focus on racially homogenous and/or ethnically different populations in other countries [21,25,26].
This review confirms that there is a paucity of well-designed studies that describe the associations between racial and ethnic disparities and adherence to opioids among patients with cancer pain. This is despite the fact that moderate to severe cancer pain in the U.S. is managed mainly with analgesics and specifically with opioids [19]. In addition, cancer patients with health insurance have both more pharmacy claims as well as more claims for higher doses of opioids [20] compared to noncancer patients. The lack of attention to analgesic and opioid adherence among cancer patients is surprising in the light of the recent high-profile initiatives to reduce opioid misuse [31].
Multiple studies highlighted the importance of pain management education and adequate pain assessment for effective analgesic use [4,16]. In the study in the palliative care setting, the authors concluded that patients who are educated, counseled, and monitored by a palliative or supportive care team have less episodes of opioid deviation and trends toward lower opioid use [12]. A systematic review and meta-analysis confirmed findings that educational interventions for patients improved knowledge about cancer pain management, however, most did not improve reported adherence to analgesics [27,28]. These findings emphasize the need for further research on interventions to improve racial/ethnic disparities in analgesic adherence for cancer pain.
Limitations
The findings of this review should be evaluated in the context of the following limitations. First, adherence to a prescribed regimen is a difficult outcome to measure and a majority of studies in this review used subjective measures to assess analgesic adherence for cancer pain. Of note, self-report was the primary measurement employed. Studies in non–cancer pain settings that have evaluated various methodological approaches to adherence measurement found that patients are likely to over-report adherence when using self-report or a diary format in comparison to an electronic monitoring system. Only 1 study in this review used an objective measure of adherence [13]. Some previous studies contend that self-report in comparison to other, objective measurements of medication adherence are accurate [23]. Further research is needed to determine the most accurate measurement of analgesic adherence in cancer patients.
Also, invariably the studies employed an English-speaking sample, which excludes an understanding of analgesic adherence for cancer pain in linguistically diverse Americans. In addition, most studies included patients who were either white Americans or African Americans and some studies lumped several racial ethnic minority subgroups as “nonwhites” or “other.”
A majority of studies were cross-sectional [4,12,15,16]. For instance, studies used a 24-hour time period to assess ATC medication as well as as-needed regimens, which may not capture the information needed to understand adherence to as-needed regimens [4]. With longitudinal studies, a greater understanding of adherence can be determined. However, there is potential bias with studies that track patients primarily at follow-up appointments. Individuals who are compliant with follow-up appointments may present with different analgesic adherence compared to those who do not attend follow-up appointments. This potential bias should be evaluated in longitudinal studies with various sensitivity analyses or using tools that identify healthy user bias.
Most studies recruited patients from outpatient oncology clinics, however, 1 study was conducted with a sample from an outpatient supportive care center managed by a palliative care team [12]. Due to the goals of palliative care, which include specialized treatment for individuals with serious illness and a focus on symptom management and relief, patients in this setting may have a different attitude toward using opioids.
Conclusion
Although data remain limited, our review suggests that while overuse of opioids has been a well-cited concern in patients with chronic non-cancer pain [21,33], cancer patients demonstrate considerable underuse and inconsistent use of prescribed analgesics. This is important as a recent study found that inconsistent adherence to prescribed around-the-clock analgesics, specifically the interaction of strong opioids and inconsistent adherence, is a strong risk factor for hospitalization among cancer outpatients who are prescribed analgesics for pain [1]. Of note, adherence to opioids in patients with cancer may be driven by a unique set of factors and these factors may differ for minorities and non-minority patients. For instance, studies in this review indicate that income is a strong predictor of analgesic adherence for African Americans but not for whites. This is because race and socioeconomic status frequently overlap in the United States [29]. In addition, like cancer pain, analgesic side effects may also be poorly managed among African Americans and other minorities. For example, in 1 study, Meghani et al used a trade-off analysis technique (conjoint analysis) to understand trade-offs African Americans and whites employ in using analgesics for cancer pain [30]. The authors found that African Americans were more likely to make analgesic adherence decisions based on side effects whereas whites were more likely to make adherence decisions based on pain relief [30]. In subsequent analysis, these authors showed that the race effect found in their previous studies was mediated by the type of analgesics prescribed to African Americans vs. whites [31]. African Americans with cancer pain were prescribed analgesics that had a worse side effect profile after statistically adjusting for insurance type and clinical risks such as renal insufficiency [31].
Together, the available evidence indicates that both patients’ socioeconomic status and clinician treatment bias contributes to racial and ethnic disparities in analgesic adherence for cancer pain and subsequent cancer pain outcomes. Thus, future research should investigate interventions for improving analgesic adherence among low-income minorities. Also, there is a need for clinician-level interventions focusing on cognitive bias modification related to cancer pain and side effects management, which appears to relate to analgesic nonadherence among racial/ethnic minorities. In addition, further research is needed to (1) rigorously describe analgesic and opioid adherence for cancer pain, (2) elucidate racial/ethnic and other socioeconomic and clinical disparities in analgesic and opioid adherence for cancer pain; (3) and clarify the role of analgesic and opioid adherence for cancer patients including outcomes for the patients and the health care system.
Corresponding author: Salimah H. Meghani, PhD, MBE, RN, University of Pennsylvania School of Nursing, Room 337, Fagin Hall, 418 Curie Blvd, Philadelphia, PA 19104, meghanis@nursing.upenn.edu.
Financial disclosures: None.
