Nonadherence Taxes Healthcare System

During the 5th annual HOPA conference, Christy S. Harris, PharmD, BCPS, BCOP, assistant professor of pharmacy practice, Massachusetts College of Pharmacy and Health Sciences, led a breakout workshop that examined outcomes related to inadequate adherence in patients with malignancy. During the session, numerous studies were reviewed that demonstrated that patients who did not comply with their oral chemotherapy regimens had worse outcomes than their adherent counterparts and were also more costly to the healthcare system, as these patients tended to require more physician visits and had higher hospitalization rates and longer hospital stays. According to Harris, “up to 69% of medication-related hospital admissions are due to poor medication adherence at a cost of around $1 billion a year.”

One of the highlighted studies used a prescription database to assess Gleevec (imatinib) adherence and medical costs for 267 patients with chronic myeloid leukemia. The mean medication possession ratio (MPR) was 77.7%, with 31% of patients experiencing treatment interruption. MPR decreased as the number of concomitant medications increased (P = .002), and was lower among women (P = .003), patients with high cancer complexity (P = .003), and in those with a higher starting dose of imatinib (P = 0.04). A 10% point difference in MPR was associated with a 14% difference in healthcare costs, excluding imatinib, and a 15% difference in medical costs. Dr Harris pointed out the relevance of these findings, stating “a 75% adherence rate incurred an additional $4000 compared with someone with an 85% adherence, so you can see how this is really going to add up as we decrease our adherence.”

According to Dr Harris, determining which patients are at risk of being nonadherent is an essential component of reigning in healthcare costs. Some of the patient populations that are known have compliance issues include women, those with depression or another psychological problem, the cognitively impaired, those who receive inadequate follow-up or discharge planning, and patients who experience medication side effects or do not believe the medication will help them. Older patients (≥65 years) and the middle-aged (35-44 years) also appear to be less compliant. Other factors that affect adherence include complexity of treatment, cost of medication, and copayments.

Oncologists should consider whether a patient is at risk of nonadherence, taking special care to educate these individuals and closely monitor their adherence to therapy, as improving adherence and limiting treatment interruptions will both optimize clinical outcomes and reduce the economic burden of treating patients with cancer.