Key findings and interpretation
The purpose of this study was to explore whether an outpatient clinic multifaceted medication review could possibly alter the overall prevalence of acute hospital admission, readmission and ED visits. First, we did not note a difference between the number of patients admitted nor the number of acute hospital admissions per patient before and after medication review. This is in line with the systematic review and meta-analysis of Huiskes et. al, that showed no effect of medication review on clinical outcomes. It should be stated however, that the mean follow-up in the research by Huiskes et al. was only 5.2 months. This follow-up period could have affected their results, because in our study most patients were admitted 6–12 months after medication review. One of the reasons we did not find any differences in the number of acute hospital admissions after medication review, could be the frailty of the study population that in general is prone to hospital admission because of old age, polypharmacy and comorbidity like dementia, chronic heart failure and Parkinson’s disease. Prior research indicated that age (≥ 65 years), number of medications and comorbidity were all associated risk factors for acute hospital admission. Moreover, all patients in our study visited the outpatient clinic with specific clinical problems such as falling or cognitive decline, indicating a higher a priori risk of hospital admission.
Second, there was no difference in the rate of 30-day and 180-day readmission. There is previous literature with low-quality evidence, suggesting an impact of pharmacist-led medication review on medication-related readmissions [24, 25]. Ravn-Nielsen et al. however showed that the combination of medication review, motivational interviewing with the patient and follow-up in primary care, had a significant effect on lowering the rates of readmission at 30 and 180 days . This suggests that solely an in-hospital medication review is not sufficient to have an effect on readmission rates, but in particular clear communication with and smooth transfer to primary care is of importance. In our study there was written communication to primary care, but due to the nature of the study, there was no control on the continued adherence to advices following from medication review. Therefore it is hypothetically possible, that less favourable medication was represcribed in primary care during follow-up, that could lead to medication-related readmission. In contrast to readmission, a review by Christensen et al. suggested that medication review might reduce the number of ED visits . Our study showed a reduction of about 20% of potentially medication related ED visits after medication review, which is in line with previous numbers estimating a reduction of 27% (ranging from 45% reduction to 3% increase in visits).
Finally, analysis of the medication in use before medication review by patients that had an acute hospital admission, showed significantly higher use of diuretics and antiparkinson drugs and a trend towards more frequent use of insulin, dementia drugs, opioids and antidepressants. The underlying diseases associated with some of these drugs, in particular dementia, Parkinson´s disease and chronic heart failure are obviously predictors of hospitalization on their own [26–28]. Our findings therefore indicate an underlying frailty in the study population because of comorbidity. On the other hand, diuretics, blood glucose-lowering agents, opioids and drugs working on the central nervous system (CNS) are in the top 10 of potentially preventable ADEs such as electrolyte disturbances, hypoglycemia and falls [29–31]. In our study diuretics, especially thiazide diuretics were regularly discontinued because of hyponatremia and falls.
Strengths and weaknesses
The strengths of this study are that we analysed the effect of a multifaceted medication review in the geriatric outpatient clinic, whereas most of previous literature focused on hospitalized patients. Moreover the follow-up was 12 months, which is longer than most studies on medication review.
This study is limited by the number of patients enrolled and the fact that it partially based on retrospective data (previous hospital admissions).
In further research we will perform a randomized trial where we analyse the effects of medication review on outcome (mortality, adverse events, length-of stay) of acutely hospitalized older patients.