Interventions for adherence with oral chemotherapy in hematological malignancies: A systematic review.

Abstract

Poor adherence to treatment for chronic diseases including some hematological malignancies impedes health outcomes and increases costs. Oral chemotherapy is an emerging trend that raises concern about nonadherence problems in these targeted patients. This systematic literature review explores evidence and gaps in the literature regarding interventions to enhance adherence with prescribed oral chemotherapy in patients with hematological malignancies. Searches of databases and abstracts from conferences were performed for 1987 to January 2013 using a modified Cochrane method. Studies measuring interventions to improve adherence alone or together with clinical, humanistic, and economic outcomes were included. Assessment of methodological quality was performed for each retained study. The literature search generated 6 studies that met inclusion criteria. Four of these reported a statistically significant increase in the adherence outcome, compared with baseline. Tailored and educational interventions were widely used among the retained studies. Post-intervention adherence rates were 41-96.1%; intervention groups yielded higher rates than comparison groups. Two studies reported statistically significant improvement in clinical outcomes (cytogenetic response and survival time). One study reported that severity of illness was associated with survival time but not with adherence. Studies that used both tailored and educational interventions showed significant relationship between adherence and clinical outcomes; however, the study that used dosage simplification did not. None of the studies explored humanistic or economic outcomes. Interventions to improve adherence with oral chemotherapies in hematological malignancies remain limited. Though they were heterogeneous in nature, interventions tested in the retained studies suggested a positive impact on the adherence outcome; some established a significant relationship between adherence and clinical outcomes. The results yielded limited evidences regarding characteristics of a specific intervention, but supported a general structure for methods to improve adherence and other outcomes in real-life settings. Further rigorous methodological studies are needed to fully examine impact on adherence and clinical outcomes.