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

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 a parts per thousand currency sign10 indicates nonadherence and a parts per thousand yen11 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.