Polypharmacy and medication regimen complexity in transfusion-dependent thalassaemia patients: a cross- sectional study

Background Medication burden and complexity have been longstanding problems in chronically ill patients. However, more data are needed on the extent and impact of medication burden and complexity in the transfusion-dependent thalassaemia population. Aim The aim of this study was to determine the characteristics of medication complexity and polypharmacy and determine their relationship with drug-related problems (DRP) and control of iron overload in transfusion-dependent thalassaemia patients. Method Data were derived from a cross-sectional observational study on characteristics of DRPs conducted at a Malaysian tertiary hospital. The medication regimen complexity index (MRCI) was determined using a validated tool, and polypharmacy was defined as the chronic use of five or more medications. The receiver operating characteristic curve analysis was used to determine the optimal cut-off value for MRCI, and logistic regression analysis was conducted. Results The study enrolled 200 adult patients. The MRCI cut-off point was proposed to be 17.5 (Area Under Curve = 0.722; sensitivity of 73.3% and specificity of 62.0%). Approximately 73% and 64.5% of the patients had polypharmacy and high MRCI, respectively. Findings indicated that DRP was a full mediator in the association between MRCI and iron overload. Conclusion Transfusion-dependent thalassaemia patients have high MRCI and suboptimal control of iron overload conditions in the presence of DRPs. Thus, future interventions should consider MRCI and DRP as factors in serum iron control.