What is already known about this subject • Polypharmacy has been linked to heightened risk of occurrence of drug‐related problems (DRPs) and a detrimental health outcome.• Polypharmacy has been variously defined; in research studies a commonly applied definition has been the concomitant use of five or more drugs.• The value of using a definite number of drugs as a cut‐off to describe polypharmacy as a risk factor for the occurrence of DRPs has not been validated. What this study adds • Nearly half of the patients admitted to general hospitals used five or more drugs; during the hospital stay these patients were prescribed as many new drugs as those admitted with fewer drugs.• The presence of DRPs increased approximately linearly with the number of drugs used, for the range of one to >11 drugs.• To set a strict cut‐off to identify polypharmacy and declare that using more than this number of drugs represents a potential risk for occurrence of DRPs, is of limited value in clinical practice.Aim: To investigate whether polypharmacy defined as a definite number of drugs is a suitable indicator for describing the risk of occurrence of drug‐related problems (DRPs) in a hospital setting.Methods: Patients admitted to six internal medicine and two rheumatology departments in five hospitals were consecutively included and followed during the hospital stay, with particular attention to medication and DRPs. Comparisons were made between patients admitted with five or more drugs and with less than five drugs. Clinical pharmacists assessed DRPs by reviewing medical records and by participating in multidisciplinary team discussions.Results: Of a total of 827 patients, 391 (47%) used five or more drugs on admission. Patients admitted with five or more and less than five drugs were prescribed the same number of drugs after admission: 4.1 vs. 3.9 drugs [P = 0.4, 95% confidence interval (CI) − 0.57, 0.23], respectively. The proportion of drugs used on admission which was associated with DRPs was similar in the patient group admitted with five or more drugs and in those admitted with less than five drugs. The number of DRPs per patient increased approximately linearly with the increase in number of drugs used; one unit increase in number of drugs yielded a 8.6% increase in the number of DRPs (95% CI 1.07, 1.10).Conclusion: The number of DRPs per patient was linearly related to the number of drugs used on admission. To set a strict cut‐off to identify polypharmacy and declare that using more than this number of drugs represents a potential risk for occurrence of DRPs, is of limited value when assessing DRPs in a clinical setting.

To assess the total systemic antiviral use in Europe and to identify the antiviral substances most commonly used. Within the European Surveillance of Antimicrobial Consumption (ESAC; www.esac.ua.ac.be), using the anatomical therapeutic chemical (ATC) classification and defined daily dose (DDD) measurement unit, data on total (out- and inpatient) systemic antiviral use (ATC J05), aggregated at the level of the active substance, were collected for 2008, and use was expressed in DDD (WHO ATC/DDD, version 2010) per 1000 inhabitants per day (DID). Antiviral substances were grouped according to their main indication. In Europe, 12 countries (Belgium, Croatia, Denmark, Estonia, Finland, France, Hungary, Italy, Luxembourg, Russia, Slovenia and Sweden) provided total (out- and inpatient) data and 4 countries (Austria, the Netherlands, Portugal and Norway) provided outpatient data only. Total systemic antiviral use varied by a factor of 10.95 between the country with the highest (3.53 DID in France) and the country with the lowest (0.32 DID in Croatia) use. HIV/AIDS antivirals represented more than 50% of the total antiviral use in most countries. The amount and spectrum of antivirals used varied greatly between countries. Our study demonstrated a wide variation of total systemic antiviral use in several European countries, as striking as that of outpatient systemic antibiotic, antimycotic and antifungal use. The variation is mainly determined by the use of HIV/AIDS antivirals. These observations should stimulate further analysis to understand the variation of specific antiviral substances. The ESAC data facilitate auditing of antiviral prescriptions and evaluation of the implementation of guidelines and public health policies.

Objectives To investigate drug regimen changes during hospitalisation and explore how these changes are handled after patients are transferred back into the care of their general practitioners (GPs). Design Cohort study. Setting Patients in this multicentre study had undergone at least one change in their drug regimens at discharge from the general medicine departments at six hospitals in Norway. These changes were altered doses, discontinuation of drugs or start of new drugs. Clinical pharmacists visited the patients’ GPs 4–5 months after patient discharge and recorded any additional drug regimen changes. Results In total, 105 patients (mean age 76.1 years, 54.3% women) completed the study. On average, they used 5.6 drugs at admission (range 0–16) and 7.6 drugs at discharge (range 1–17). On average, 4.4 drug changes per patient (SD 2.7, range 1–16) were made at the hospital, and 3.4 drug changes per patient (SD 2.9, range 0–14) within 4–5 months of discharge. Of the 465 drug changes made in hospital, 153 were changed again after discharge (mean 1.5 per patient, SD 1.8, range 0–13). The drug regimens of 90 of these 105 patients were changed after discharge. The OR for extensive drug changes after discharge (≥ 4 changes) increased significantly with the number of drugs used at discharge from hospital (OR=1.29, 95% CI 1.04 to 1.59). Only 68 of 105 discharge notes contained complete drug lists, and only 24 of the discharge notes were received by the GPs within 7 days. Conclusions In addition to the extensive changes in drug regimens during hospitalisation, almost equally extensive changes were made in the initial months after discharge. Surveillance of drug regimens is particularly necessary in the period immediately after hospital discharge.