Failure mode and effects analysis of medication adherence in patients with chronic myeloid leukemia

Poor adherence to ABL tyrosine kinase inhibitors (ABL TKIs) is associated with reduced treatment efficacy and increased healthcare costs. To examine the hazards associated with poor adherence, we implemented failure mode and effects analysis (FMEA).

We surveyed 54 chronic myeloid leukemia (CML) patients treated at Saga University Hospital from October 2012 to May 2014. The survey consisted of items regarding the type of ABL TKI used, adherence to ABL TKIs, the appearance of adverse effects, utilisation of the high cost medical care benefit system, and factors affecting adherence. Four factors that likely affected adherence were identified, including the level of understanding of ABL TKIs treatment outcomes, adverse effects, the high cost of medications, and careless slips in the taking of medicine. Results of the survey were analysed by FMEA.

The risk priority number was highest for careless slips in the taking of medicine at 7.0 ± 1.0 (mean ± SEM), followed in descending order by the inadequate understanding of treatment outcomes (4.9 ± 0.6), adverse effects (3.8 ± 0.8), and high medication cost (2.2 ± 0.5). Thus, the prevention of careless slips was the most important factor affecting adherence to ABL TKIs. Contrary to our preoccupation, FMEA revealed that high medication cost was the lowest risk factor for poor adherence. This finding may be attributed to the high utilisation (96.3 %) of the high cost medical care benefit system.

These findings suggest that an inadequate medication-taking habit such as careless slips may represent a potential target to improve and maximize adherence in CML patients.