Good adherence to imatinib therapy among patients with chronic myeloid leukemia—a single-center observational study

Abstract

Previous studies have suggested that adherence to imatinib therapy can be an obstacle among patients with chronic myeloid leukemia (CML). We studied adherence to imatinib therapy among CML patients treated at the Sahlgrenska University Hospital. We identified all CML patients that were alive at the 1st of January 2010 (n = 70). Nineteen patients were excluded due to a history of allogenic hematopoietic stem cell transplantation, and nine were excluded due to treatment with other tyrosine kinase inhibitors. Thirty-eight out of 42 patients (90%) treated with imatinib accepted inclusion in the study. The patients were interviewed in a structured way, and adherence was evaluated in a standardized way using the nine-item Morisky Medication Adherence Scale that ranges from 1 to 13. A Morisky score ≤10 indicates nonadherence and ≥11 indicates adherence. In addition, predefined follow-up questions were asked to identify factors known to influence adherence to therapy. In contrast to previous studies, our patients showed good adherence to imatinib therapy with a mean Morisky score of 12.3 out of 13 (range, 9-13). The interviews revealed factors known to predict adherence to therapy, namely being well informed and having frequent contact with a single hematologist. Furthermore, the patients had easy access to the treating clinic and felt that they took part in decisions concerning their disease and treatment. We show that adherence to imatinib can be very good in CML patients, and we suggest that simple measures such as increased patient information and continuity of care will increase adherence in patients with CML.

Measurement of adherence to BCR-ABL inhibitor therapy in chronic myeloid leukemia: current situation and future challenges

“…Eight publications came from Europe, 14,15,18,19,21,24,25,30 5 from the US, 20,23,[31][32][33] 5 from Asia 22,26,28,29,35 and one from Australia.…”

“…An overview of the included articles is given in Online Supplementary Table S3. 14,15, Only 19 peer review articles were analyzed and reported in the Results section.Eight publications came from Europe, 14,15,18,19,21,24,25,30 5 from the US, 20,23,[31][32][33] 5 from Asia 22,26,28,29,35 and one from Australia.27 Almost half of the included studies were retrospective (9 of 19) and mainly conducted in the US and Asia 38,41,42,45,49,52,53 while half of the European studies were prospective (4 of 8). 14,15,18,24 …”

“…electronic compilation of drug dosing histories like Medication Event Monitoring Systems (MEMS ® ), 15,24 blood sampling to measure drug levels, 18 or diary logs and questionnaires in cross-sectional studies. 25,27 Few studies used a combination of measurement methods such as a questionnaire or patient diary log combined with pill count, appointments kept or MEMS ® .14, 21 We assessed the adherence method sampling rate used in each study to provide information on the dynamics of adherence over time, as well as to prevent a clear distinction being made between suboptimal implementation of a dosing regimen and short persistence in case of low sampling rate. In general, the rates observed in this review were very low with yearly MPR computed over the entire period of follow up.…”

“…a patient was non-adherent if intake was less than 80-90% of total medication) and measured by MEMS ® , MPR, or questionnaire, 3-56% of patients were classified as non-adherent (Figure 4). 14,15,[22][23][24][25]32,34 …”

“…From 'most frequent' to 'least frequent' these were: adverse events (AEs); 15,21 dose; 14,15,20,27 disease duration; 14 treatment duration; 14,23 a good patient-physician relationship and sufficient disease-related education. 14,25 In CML, drug-related AEs were the most common reason for intentional non-adherence whereas forgetfulness was the most common reason for unintentional nonadherence. …”