Cancer

Cancer-Related Pain: Attention to Medication Reconciliation

CANCER-PAIN MANAGEMENT – PART II

Analgesics are the cornerstone of cancer pain management in all age groups, but the primary care provider must take into account comorbidities, age-related changes, and potential drug-drug interactions in older patients before prescribing a pain-killer in older adults. This second article in the series reviews the pharmacological considerations for starting and continuing pain medication in older adults and the elderly, with special attention paid to the role of the clinical pharmacist as part of the interdisciplinary care team and how to reduce the risks associated with aberrant drug use.

The Nature of Pharmacological Pain Management in the Elderly

The American Geriatrics Society has a guideline for pain management in the older patient.1 Even though the elderly have greater intolerance to nonsteroidal anti-inflammatory drugs, fewer opioid receptors in the central nervous system, altered ratios of mu and delta opioid receptors, and increased sensitivity to opioids, the general principles of treatment initiation for moderate to severe pain are the same as in younger patients: prescribe an immediate-release opioid by mouth, titrate the dose to effect, then convert to a long-acting preparation.2 Age-related physiologic changes and disease-related changes in organ function do have to be taken into account, however, as they affect the drug’s pharmacokinetics and pharmacodynamics. On the one hand, reductions in lean body mass and total body water decrease the volume of distribution of hydrophilic analgesics such as morphine. On the other hand, increases in body fat in the elderly results in a larger volume of distribution for lipophilic analgesics such as fentanyl, resulting in a longer time to reach steady state and delayed elimination of pain medicine should start lower and increase slower to account for these changes.3-5 Age-related changes in hepatorenal function also decrease the clearance of drugs. Pharmacotherapy becomes very complex when the older patient also has serious comorbidities, a long list of medications taken at home, prescribers and pharmacies located in different cities and states, cognitive changes, and/or caregiver issues. These patients are at increased risk of under- and over-treatment, adverse effects, drug interactions, and poor outcomes.
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RELATED CONTENT
Chronic Musculoskeletal Pain: Rational Use of Opioid Analgesics
Opioid Analgesics for Persistent Pain in the Older Patient
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Role of the Pharmacist

For most part, medication therapy is the backbone for the outpatient management of pain, ranging from over-the-counter medications to prescription opioid therapies. Proper medication selection is critical for all patients and close attention should be paid to older patients’ renal and hepatic function. The majority of patients utilize a prescription drug benefit plan that may result in potential barriers to obtaining the prescribed medications. While an in-house clinical pharmacologist is a great asset as a member of the multidisciplinary team in the hospitals, community-based pharmacists have the potential to play a vital role in assisting with selecting appropriate and safe medications, navigating the insurance maze, providing patient education and monitoring patient outcomes. In the outpatient setting they are also of great value in helping with the required reconciliation of the home medication list, which is a national patient safety goal of the Joint Commission on Accreditation of Healthcare Organizations. Patients admitted to a hospital commonly receive new medications or have changes made to their existing medications. Clinicians may sometimes not be able to easily access patients’ complete medication lists, or may be unaware of recent medication changes. As a result, the new medication regimen prescribed at the time of discharge may inadvertently omit needed medications, unnecessarily duplicate existing therapies, or contain incorrect dosages.

Such unintended inconsistencies in medication regimens may occur at any point of transition in care (eg, transfer from an intensive care unit to a general ward), as well as at hospital admission or discharge. Studies have shown that unintended medication discrepancies occur in nearly one-third of patients at admission, a similar proportion at the time of transfer from one site of care within a hospital. In one study, 62 (41.3%) patients out of 150 at hospital discharge had at least one actual unintentional medication discrepancy at hospital discharge and 83 patients (85.3%) had at least one potential unintentional discrepancy.6 Medication reconciliation refers to the process of avoiding such inadvertent inconsistencies across transitions in care by reviewing the patient's complete medication regimen at the time of admission, transfer, and discharge and comparing it with the regimen being considered for the new setting of care. Though most often discussed in the hospital context, medication reconciliation can be equally important in ambulatory care, as many patients receive prescriptions from more than one outpatient provider.6

Effective January 1, 2013, as part of the National Patient Safety Goal (NPSG), the Joint Commission Accreditation for Ambulatory Care has focused on risk points of medication reconciliation.7 To use medicines safely, it is recommended that correct information about a patient’s medications be recorded and passed along. Comparison must be made between old and new medications. Effort must be made to make sure that the patient knows which medications to take when they are at home. A good faith effort to collect this information is recognized as meeting the intent of the requirement while the health care is still evolving with the adoption of more sophisticated systems, such as centralized databases for prescribing and collecting medication information. A new requirement in this NPSG addresses the patient’s role in medication safety: it requires organizations to inform the patient about the importance of maintaining updated medication information.8

(Attention to Aberrant Drug Use on next page)

Attention to Aberrant Drug Use

Aberrant drug taking behaviors are relevant in the elderly, as substance abuse is not just a problem in patients 65 years of age, and is an emerging issue which complicates geriatric cancer pain management. The number of older adults in need of substance abuse treatment is estimated to increase from 1.7 million in 2000 and 2001 to 4.4 million in 2020. This is due to a 50% increase in the number of older adults and a 70% increase in the rate of treatment need among older adults.9 The aging baby boom cohort will place increasing demands on the substance abuse treatment system in the next two decades, requiring a shift in focus to address the special needs of an older population of substance abusers. There is also a need to develop improved tools for measuring substance use and abuse among older adults.9

In a literature search by Tylor and Grossberg10 on the growing problem of illicit substance abuse in the elderly, a total of 26 articles were identified with a focus on use of illicit substances, excluding alcohol, over-the-counter drugs, and prescription drugs in the elderly. Limited data were available to combine between studies, but certain conclusions could be generalized among separate sources. They noted that illicit substance abuse has been incorrectly assumed to end as patient’s age, whereas in reality, elderly drug users are increasingly common and have a unique profile quite different from that of their younger counterparts. They concluded that geriatric substance abuse is a common problem and includes both licit and illicit substances. There are not yet reliable screening instruments or treatment methods for identification and treatment of illicit substance abuse in the elderly. A high index of suspicion and consideration of illicit substance use as a real possibility are vital for early recognition and diagnosis of such abuse in the elderly and to safely prescribe pain medications for them.10 Also, patients and their families may be concerned about relapse, and this is a potential barrier to adherence with pain medicine recommendations. Referral to an addiction psychiatrist may be required and must be laid out upfront during clinic visits. It should clarified as part of standard of care and harm reduction.

Drug diversion is also a potential problem in this age group. While patients are unlikely to sell their medicines, younger family members with drug dependency issues may steal their relatives’ pain medicines. Patient education about safe storage and disposal of pain medicines is an important part of comprehensive care in the elderly. The diversion of prescription opioids might be reduced through physician education, with a focus on: (1) recognizing that a patient is misusing and/or diverting prescribed medications; (2) considering a patient's risk for opioid misuse before initiating opioid therapy; and (3) understanding the variation in the abuse potential of different opioid medications currently on the market. Patient education also appears appropriate in the areas of safeguarding medications, disposal of unused medications, and understanding the consequences of manipulating physicians and selling their medications.11

Prescription Drug Monitoring Program

Various states have now implemented the Prescription Drug Monitoring Program(PDMPs), which further assists clinicians in safe prescribing and become aware of multiple prescribers. According to the National Alliance for Model State Drug Laws, a PDMP is a statewide electronic database that collects designated data on substances dispensed in the state. The PDMP is housed by a specified statewide regulatory, administrative or law enforcement agency. The housing agency distributes data from the database to individuals who are authorized under state law to receive the information for purposes of their profession. The US Drug Enforcement Administration is not involved with the administration of any state PDMP.

The National Alliance for Model State Drug Laws clearly identifies the benefits of a PDMP: as a tool used by states to address prescription drug abuse, addiction and diversion, it may serve several purposes such as:

  1. Support access to legitimate medical use of controlled substances
  2. Identify and deter or prevent drug abuse and diversion
  3. Facilitate and encourage the identification, intervention with and treatment of persons addicted to prescription drugs
  4. Inform public health initiatives through outlining of use and abuse trends, and
  5. Educate individuals about PDMPs and the use, abuse and diversion of and addiction to prescription drugs.12

As of October 2011, the US Office of Diversion Control reported that 37 states have operational PDMPs that have the capacity to receive and distribute controlled substance prescription information to authorized users.12

Roma Tickoo, MD, MPH, is an assistant attending in pain and palliative care services, Department of Medicine, at Memorial Sloane Kettering Cancer Center, New York, NY.

Paul Glare, MD, is chief of palliative medicine service, Memorial Sloane Kettering Cancer Center, New York, NY.

Amitabh Gulati, MD, is director of ambulatory pain management, Memorial Sloane Kettering Cancer Center, New York, NY.

Andreas Rimner, MD, is a board-certified radiation oncologist at Memorial Sloane Kettering Cancer Center, New York, NY.

Eric Lis, MD, is director of interventional neuroradiology at Memorial Sloane Kettering Cancer Center, New York, NY.

References

  1. AGS Panel on Persistent Pain in Older Persons. Pharmacologic management of persistent pain in the older persons. J Am Geriatr Soc. 2009;57(8):1331-1346.
  2. Forman WB. Opioid analgesic drugs in older people. Clin Geriatr Med. 2001;17(3):479-487.
  3. Cusack BJ. Pharmacokinetics in older persons. Am J Geriatr Pharmacother. 2004;2(4):274-302.
  4. Montamat S, Cusack B, Vestal R. Management of drug therapy in the elderly. N Engl J Med. 1989;321(5):303-309.
  5. Avorn J, Gurwitz J, Rochon P. Principles of pharmacology. In: Cassel CK, Leipzig R, Cohen HJ, Larson EB, Meier DE, eds. Geriatric Medicine: An Evidence-Based Approach. New York: Springer, 2003:65-82.
  6. Reyes-Gibby CC, Aday LA, Anderson KO, Mendoza TR, Cleeland CS. Pain, depression, and fatigue in community-dwelling adults with and without a history of cancer. J Pain Symptom Manage. 2006;32(2):118-128.
  7. Hospital Accreditation Program. National Patient Safety Goal (NPSG) Goal 3: Improve the safety of using medications. NPSG.03.04.01. In: Commission TJ, ed2013.
  8. Vuorinen E. Pain as an early symptom in cancer. Clin J Pain.1993;9(4):272-278.
  9.  Gfroerer J, Penne M, Pemberton M, Folsom R. Substance abuse treatment need among older adults in 2020: the impact of the aging baby-boom cohort. Drug Alcohol Depend.  2003;69(2):127-135.
  10. Taylor MH, Grossberg GT. The growing problem of illicit substance abuse in the elderly: a review. Prim Care Companion CNS Disorders. 2012;14(4).
  11. Inciardi JA, Surratt HL, Cicero TJ, Beard RA. Prescription opioid abuse and diversion in an urban community: the results of an ultrarapid assessment. Pain Med. 2009;10(3):537-548.
  12. State Prescription Drug Monitoring Programs. Office of Diversion Control, US Department of Justice. 2013. www.deadiversion.usdoj.gov/faq/rx_monitor.htm. Accessed April 11, 2014.