Objectives To evaluate characteristics of the medication complexity, risk factors associated with high medication complexity and their clinical consequences in patients with advanced chronic conditions.

Methods A 10-month cross-sectional study was performed in an acute-hospital care Geriatric Unit. Patients with advanced chronic conditions were identified by the NECPAL test. Medication complexity was established using the Medication Regimen Complexity Index (MRCI) tool. Demographic, pharmacological and clinical patient data were collected with the objective of determining risk factors related to high medication complexity. Measured clinical outcomes were hospital length of stay, destination on hospital discharge, in-hospital mortality and 2-year survival.

Results Two hundred and thirty-five patients (mean age 86.8, SD 5.37; 65.5% female) were recruited. MRCI’s mean score was 38 points (SD 16.54, rank: 2.00–98.50), with 57.9% of patients with high medication complexity (MRCI >35 points).