Background: Patient adherence is necessary for successful medication therapy. However, highly complex medication regimens may lead to poor adherence, which decreases the effectiveness of treatment and often results in treatment failure, excessive morbidity and mortality, and higher costs.
Objective: To examine whether patient adherence can be increased indirectly through reducing medication complexity by (a) pharmaceutical counseling of hospital medical staff and (b) additional information in the discharge letter for the primary care provider (PCP) about the simplified discharge medication.
Methods: At the Medical Center Hamburg-Eppendorf, a tertiary care university hospital in Germany, 240 chronically ill inpatients with hypertension, diabetes, and/or dyslipidemia were enrolled in this prospective, semirandomized study. For the intervention group, hospital doctors were counseled by a clinical pharmacist on feasible simplifications of cardiovascular and antidiabetic medications. In 1 randomized subgroup, the PCP received additional explanatory information in the discharge letter. Adherence (self-reporting using the Medication Adherence Rating Scale [MARS-D]) and medication complexity (using the Medication Regimen Complexity Index [MRCI-D]) were recorded at admission to the hospital, discharge from the hospital, and 6 weeks after discharge. Patient quality of life (QoL) and satisfaction with information about medications were assessed at admission and after discharge.
Results: At discharge, the medication regimen in the intervention group was significantly less complex than in the comparison group. Yet, 6 weeks after discharge, the complexity of the outpatient medication had increased to values similar to the comparison group, unless the PCP received additional information in the discharge letter. Propensity adjusted complete adherence rates at discharge were slightly, but not significantly, higher in the intervention group than in the comparison group. Within the intervention group, complete adherence was more frequent in the subgroup with additional information for the PCP. Patient QoL and satisfaction with information were comparable in both groups.
Conclusion: The complexity of cardiovascular and antidiabetic hospital medications can be reduced by counseling the hospital doctors. However, for a sustainable simplification of outpatient medication, the PCPs must receive explicit information about the modifications. Patient adherence was not significantly influenced by this intervention. To verify these results, further research with objective measures of adherence and in patients with other diseases is needed.