Patologie iatrogene in anziani fragili in politerapia. Analisi farmacoepidemiologica in diversi servizi assistenziali e sviluppo di un progetto per la prevenzione delle reazioni avverse prevedibili ed evitabili

Abstract

Background. Potentially inappropriate prescriptions (PIPs) are highly prevalent among older people and they are associated with adverse drug reactions (ADRs), hospitalization and wasteful utilization of resources. Interventions to optimize prescribing appropriateness in older patients have shown mixed results. The choice of the best intervention for an optimization of drug prescribing in this group of patients has become an important public-health issue worldwide. Aim. The aim of this study was to develop and validate a new Computerized Provider Order Entry Warning Integrated System (CPOE-WIS) in terms to reduce clinical relevant PIPs in three different care settings: hospital, nursing home and domiciliary integrated assistance. Methods. CPOE-WIS was developed from a first cohort of elderly patients, then it was tested and validated in a different cohort of consecutively hospitalized patients. For each patient, demographic detail, diagnosis and chronic drug therapy were processed by CPOE-WIS. The output was a report of all PIPs identified by STOPP criteria and/or all clinically relevant drug-drug interactions (DDIs) identified by Micomedex (Drug-Reax). The report was discussed with the physician in charge by a pharmacist and the improvement of the prescription appropriateness was measured by the MAI (Medication Appropriateness Index) prior and after intervention. Results. At admission, the development and validation cohorts were well balanced regarding age, gender, MPI (frailty score), number of drugs and PIPs. In both cohorts PIPs use was associated with high degree of polytherapy (≥ 5 drugs). After intervention, the number of PIPs, in terms of summated MAI per patient, was reduced in all care settings: hospitalized patients [3 (IQR=3-5) vs 2 (IQR=0-4); p<0.001], nursing home patients [4 (IQR=2-2.75) vs 2 (IQR=1-4); p<0.001], domiciliary integrated assistance patients [4 (IQR=2-6) vs 3 (IQR=0-5); p<0.05]. The number of patients with improvement of appropriateness was respectively 62.0% in hospital, 51.7% in nursing home and 49.1% in domiciliary integrated assistance. Conclusion. This study showed that the pharmacist intervention and use of a new CPOE-WIS to screen the clinical and prescription data resulted in a significant improvement in prescribing appropriateness in terms of reducing MAI score in three different care setting. In particular, intervention reduced the use of (i) unnecessary drugs (absence of indication or duplicate prescription); (ii) the risk of drug-drug and drug-disease interactions and (iii) the prescription of drugs at inappropriate dose or duratio