Discussion
Based on a literature search and review, and on questions to our international network, we believe this is the first prospective and controlled study to evaluate a community pharmacy based CDSS on pharmacists’ identification and resolution of DRPs. Our study is small, but it indicates that the EES-support system contributes to identification of actual drug related problems (DRPs). The number of patients with at least one DRP did not increase but the number of patients with at least 1, 2 and 3-5 DRPs did. This is what should be expected for a support system. EES gives a total review of all prescriptions. This helped the pharmacist to suggest initiatives towards physicians, but not toward patients to resolve DRPs. The help mainly concerned drug-drug interactions. This seems to be the major contribution of EES, to assist pharmacists in suggesting the removal or switch of a drug, or decrease the dose due to drug-drug interactions. In fact, if the drug-drug interaction DRPs are removed (table 4) there is no apparent difference between the groups.
There have been few publications on systematic documentation and resolution of DRP in community pharmacies.7-11 In a German study from 2005, DRPs were examined at 1,114 pharmacies.7 The pharmacists documented approximately 10,500 DRPs, and more than 80 percent of the DRPs could be resolved, in large part in consultation with the prescriber. In another German study, 141 pharmacists documented 912 medication reviews during 2012-2015.11 In 869 of these (95%), the pharmacist documented at least one DRP. In total they found 5248 DRPs. In 3972 of these (76%), an action to solve the problem was documented and in 3198 (61%) it was rated as resolved. In a Dutch study from 2012, data was collected from 268 community pharmacies.8 In total, 4579 medication reviews were performed and 13,366 DRPs were found, on average 2.9 per patient, of which 0.90 led to medication changes. A French study from 2014 included 892 patients from 55 pharmacies. 334 DRPs were identified, 259 actions were reported and 89 were sent to the physician who implemented 70 of these.10
All studies were performed on populations similar to ours, with limited access to health-care patient data, but in several community pharmacies: They used standardized documentation templates but the method or support system (CDSS) for identification of DRPs was not described. We have found only one community pharmacy study using a CDSS and reporting DRP signals similar to our study.11 This is a Dutch study from 2014 where they took a random sample of 10% from a CDSS database from 123 pharmacies, generating 1,672,169 dispensed prescriptions from 81,742 patients. Of the dispensed prescriptions 43% led to one or more safety alerts, 31-55% range over pharmacies. They reported that the majority of the alerts were clustered in a minority of patients and involved mainly drug-drug interaction (15%), disease-drug interactions (14%), duplicate medications (13%) and dosing alerts (7%). They did not report actions or resolution rates.
We were very surprised by the low number of identified DRPs in our study, compared to other studies 7-11 and our power calculation was consequently not fully appropriate. The definition of a DRP is part of the discrepancy. It seems as most of DRPs in the described studies are potential. In our study only actual DRPs were documented. Our study pharmacy has for many years had a close collaboration with the local GPs and also a continuity among the patients coming to the pharmacy. It could be that the patients in fact are very well treated, having a low number of DRPs.
Two studies have previously been published in the EES-support system based on nursing home patients with multi-dose drug dispensing.13-14 In order to get an idea of the clinical significance of EES signals, physicians’ views on the signals were assessed.13 Sixty-eight percent (502/740) were considered clinically relevant and in 276 of these had the physician intended to take action. For 135 of these 276, the measures were to either insert or withdraw drugs, or reduce or increase the dose. Following up, it was shown that 85 of these 135 had led to an actual change in the prescription. In another study EES alerted in 76 percent of patients.14 The most common alerts were drug-drug interactions, drug duplications and inappropriate drugs or high doses in older patients. The basics in these studies are similar to ours but but the higher number of DRPs could be explained because they also documented potential DRPs.
There are some limitations in our study. The participating pharmacists were aware of the study and the EES support period. However the number of patients with at least 1 DRP was in fact lower in the EES-group which indicates a low risk of attention bias. Due to a single center study design involving only three pharmacists with different experiences the generalizability could be low. However, since the use of EES is very standardized, the different experiences among our pharmacists might increase the generalizability.
Previous studies13-14 have shown the clinical significance of the system and pharmacist suggestions. This study adds information that EES-support increases the identification, suggestions and resolving of DRPs. Future studies should focus more on clinical effects of EES-support, and cost-effectiveness. A major problem is also to involve the pharmacies/pharmacists in the establishment of a correct medication list of what medicines the patients actually take. We have previously studied this as part of the Lund Integrated Medicines Management model and found major problems in the correctness of medication lists when patients are admitted and discharged from hospital.17 Cancelation of not used prescriptions is possible by pharmacists and could be an active and integrated part to help patients and health-care professionals to establish a correct medication list, which needs to be studied.