The research group at Nordic School of Public Health NHV, Sweden, investigated preventable adverse drug reactions, i.e. side effects of medicines, in different patient groups. They found that 52% of adverse drug reactions experienced by outpatients getting hospitalised or visiting emergency care could have been prevented.
In this outpatient group, 2% of all patients suffered from preventable adverse drug reactions. According to the study, 45% of adverse drug reactions experienced by inpatients during hospitalisation could have been avoided, but the percentage of inpatients with preventable adverse drug reactions could not be estimated precisely.
Pharmacist Katja M Hakkarainen and colleagues made these findings when they summarised the results of 22 research articles published in 1994-2010, from Asia, Australia, Europe, and North America.
The studies included 48 797 outpatients getting hospitalised or visiting emergency care, and 24 128 inpatients in hospitals. In the summarised studies, an adverse drug reaction was considered preventable when the medication therapy was not in accordance with practice standards, for example dosing or monitoring was inappropriate.
“Our study shows that preventable adverse drug reactions are a significant burden to healthcare,” says Ms Hakkarainen. She points out, however, that the results can not be generalised to all practise settings, but the study provides important evidence on how widespread preventable adverse drug reactions are.
“Although medication safety practices are being improved in many countries, our results indicate that further safety measures need to be incorporated into healthcare,” continues Ms Hakkarainen.
The study also concluded that preventable adverse drug reactions should be further investigated in primary care, as no such studies were found.
“We hope this research will motivate policy makers, practitioners and researchers to invest on preventing unnecessary adverse reactions to medicines in the future.”
The article (http://dx.plos.org/10.1371/journal.pone.0033236) “Percentage of patients with preventable adverse drug reactions and preventability of adverse drug reactions – a meta-analysis” is published by PLoS ONE on 15th March 2012. The research was done in collaboration with the Nordic School of Public Health NHV and Linköping University, and the research group consisted of Katja M Hakkarainen, Khadidja Hedna, Max Petzold and Staffan Hägg.