Impact of Hospitalisation on the Complexity of Older Patients' Medication Regimens and Potential for Regimen Simplification

Aim To investigate the impact of hospitalisation on the complexity of older patients' medication regimens; and to determine whether discharge medication regimens could be simplified. Method Medication Regimen Complexity Index (MRCI) scores were calculated on admission and discharge for 186 consecutive patients (mean age 80 years) discharged from 2 acute general medicine and 2 subacute aged care wards. A random sample of 40 discharge medication regimens were retrospectively simplified by clinical pharmacists and proposed changes reviewed by a clinical pharmacologist to determine feasibility of the changes and likelihood of equivalent therapeutic outcomes. Results On average, 1.2 regularly scheduled long‐term medications/patient were ceased in hospital and 2.5 added. 0.6 regularly scheduled short‐term (defined duration) medications were commenced. MRCI scores increased by 22% (18 to 22; p < 0.0001) for regularly scheduled long‐term medications and 32% (21 to 27; p < 0.0001) for all medications. In multivariate analysis, using fewer medications prior to admission and being discharged from a subacute aged care ward were associated with increased regimen complexity. For the 40 discharge medication regimens reviewed, 90 simplifications to regularly scheduled long‐term medications were proposed, and 84 (93%) were rated by the clinical pharmacologist as feasible and likely to have the same or similar therapeutic outcomes to the complex regimens. These changes, if implemented, could have reduced medication regimen complexity at discharge by an average of 14%. Conclusion Hospitalisation resulted in multiple medication changes and increased regimen complexity. Most medication regimens had the potential to be simplified.