Memory Problems and Depression Can Predict Nonadherence to Oral Anticancer Agents

A number of risk factors can play a role in nonadherence, including older age, memory issues, and depression.

Bettina Ryll, MD, PhD

The problem of patients not taking their oral anticancer medications as prescribed continues to vex oncology practitioners. It turns out that a number of risk factors can play a role in nonadherence, including older age, problems with working memory, and feelings of depression, suggesting that current notions of nonadherence may be too narrowly focused.

These findings from a pilot study by a team of researchers at the Centre Francois Baclesse in Caen, France, were reported at the recent annual meeting of the European Society of Medical Oncology in Copenhagen. The aim of their study was to prospectively identify profiles of patients who would be less prone to follow their prescribed oral therapies.

To do this, they enrolled 126 patients who were beginning their first oral anticancer therapy and had a median age at baseline of 70 years. Researchers used a neuropsychological battery of tests to assess the patients’ cognitive function; feelings of autonomy, depression, and anxiety were also captured, along with sociodemographic information.

Participants’ adherence was then measured 1 and 3 months after their treatment started through self-assessment questionnaires and clinician observations recorded on an observance sheet.

Researchers presented their findings at ESMO after the 1-month follow-up; 111 patients completed the questionnaire, representing a response rate of 88%. Overall adherence was 90%; however, working memory disorders and depression were significantly associated with nonadherence, 1.38 (range, 1.03-1.85) and 4.67 (range, 1.11-19.59), respectively.

The study concluded that both working memory dysfunctions (frequently observed among elderly patients) and depression appear to be predictors of nonadherence.

Study authors noted in a statement that these findings highlight that cognitive disorders may be an “underestimated major parameter, notably among elderly patients” and that focusing on cognitive functions before initiation of oral anticancer therapy is relevant to identify the patient profiles more likely to fail self-management of oral anticancer therapy. They added that having this information can help clinical decision-making, particularly with elderly patients.

Intentional Nonadherence to Oral Therapies

Beyond these factors, do patients actively choose not to take their medicine? Bettina Ryll, MD, PhD, a researcher at Uppsala University in Sweden and chair of the ESMO Patient Advocacy Working Group, explained in a statement that they do:

“I believe the current concept of adherence is too narrow, ie, physicians expect patients to take their medication as prescribed and nonadherence is considered a form of disobedience. Intentional nonadherence—the patient deciding not to take medication as indicated—is actually revealing patients’ true preferences, and these might simply be very different from what physicians and other stakeholders consider relevant.”

Instead of enforcing adherence against patients’ preferences, Ryll suggested that clinicians endeavor to understand the factors driving their nonadherence to improve outcomes for patients most at risk.

Dos Santos M, Lange M, Clarisse B, et al. Impact of cognitive functions on oral anticancer therapies adherence. Presented at: 2016 ESMO Congress; October 7-11, 2016; Copenhagen, Denmark. Abstract 1497P.