In Oral Chemo Era, Non-Adherence Problems May Only Get Worse

PHOENIX, Arizona-Noncompliancewith cancer therapy is goingto become a very serious issue asmore chemotherapy drugs becomeavailable in oral formulations, accordingto Deborah Boyle, RN, MSN,AOCN, FAAN."The growth of oral chemotherapyis expansive," said Ms. Boyle, a practiceoutcomes nurse specialist withBanner Good Samaritan RegionalMedical Center, Phoenix, Arizona."I had an 'aha!' moment when discussinga patient with a radiation oncologycolleague who specialized inbreast cancer, when she posed thequestion, 'Has anyone ever thought ofall the women who took adjuvanttamoxifen-how do we know theytook their pills as prescribed?"'Tamoxifen AdherenceA recent investigation that addressedthis issue (J Clin Oncol 21:602-606, 2003) found that the mean levelof adherence to tamoxifen was actuallysomewhat higher than for othermedications; however, nearly 25% ofpatients were at risk for inadequateclinical response resulting from pooradherence.Overall adherence had fallen toabout 50% in year 4 of tamoxifen therapyin this study, which was based ona review of prescription records forabout 2,400 women enrolled in NewJersey Medicaid or pharmaceuticalassistanceprograms."We are making all these assumptionsabout how to base our treatmentdecisions, prognosis, and further therapy,and we don't even know if thosepatients took their pills the way theyshould have," Ms. Boyle said. "This isa huge issue with overwhelming significancein the future."The literature contains little guid-ance for clinicians on the issue of medicationadherence specifically in elderlycancer patients, Ms. Boyle said (JNatl Cancer Inst 94:652-661, 2002).However, some studies of medicationadherence do suggest that when anolder person takes four or more drugsroutinely, the clinician should assumethat at least one of them is not beingtaken as directed.The extent to which patients misunderstandmedication use can be significant.Ms. Boyle shared one anecdoteregarding a home-care nurse whoasked an elderly patient about a largebowl of prescription pills on his diningroom table. The elderly man explainedthat the bowl contained all hismedications for the day; every time hewalked through the dining room, hewould grab a handful and take them."All he knew was these pills have toget in this body over a 24-hour period,"Ms. Boyle said. "He could see noproblem with his way of dealing withthat ongoing demand."Two or More MedicationsPer DayIn general, the elderly take twomedications daily, most commonlycardiovascular, analgesic, or centralnervous system drugs, according todata presented by Ms. Boyle (J AmGeriatr Soc 50:26-34, 2002). The highestprevalence of medication use isamong women over 65 years of age;23% take at least five prescription drugsdaily, and 12% take 10 drugs daily.Implications of nonadherence incancer can be serious. For example, anonadherent patient's condition couldworsen as a result of inadequate drugconsumption. As a consequence, thatpatient might then have to undergounnecessary diagnostic testing andeven hospitalization. Additionally,changes in the dose or regimen mightbe made unnecessarily.Problems of NonadherenceCancer patients who are nonadherentmay require more doctor visits,more hospitalizations, and longerlengths of stay when they are hospitalized.The value of clinical trials maysuffer, as well: nonadherence couldlead to misleading results, inconsistentresponse rates, and potentiallyerroneous dosing recommendations."There are a myriad of problemsthat need to be identified," Ms. Boylesaid, including:

• What risk factors are associatedwith nonadherence?
• How do cost, anxiety, and memoryand hearing impairments affectadherence?
• What strategies improve adherence?Ongoing education? Written reminders?Phone follow-up? Memoryenhancingdevices?

Medication logs and diaries canhelp with surveillance of adherence,Ms. Boyle said. Having patients bringin their medications for review canalso foster clarification and addressinaccurate practices. This practice mayalso reveal the patient's use of herbaltherapies."The most profound take-homemessage in all of this is that cancerhealth care providers should expectproblems with adherence," she added."The appropriate and prescribed regimenof drug consumption shouldnever be assumed."