Polypharmacy : Effects of medication reviews on medication prescription policy in polypharmacy patients in the Netherlands

Background: Polypharmacy, the use of five or more drugs chronically for different therapeutic (sub)groups, is a frequent phenomenon in elderly. It is associated with negative consequences; the risk of having drug-related problems increases with the increase of number of drugs. To reduce this risk, medication reviews have to be performed according to the Dutch guideline ‘Polyfarmacie bij ouderen’. In the Netherlands, little is known about the effect of performing a medication review on the Dutch prescription policy in the Netherlands. This study will focus particularly on this effect. Methods: Two study designs are used in this study. A prospective longitudinal intervention study with a pre-test/post-test without control group, and a cross-sectional explorative cohort study have been conducted. The study population consisted of a convenience sample of patients, and their general practitioners and pharmacists in five community pharmacies in Twente with polypharmacy, of which the medication has been reviewed. Data of this population is collected through pharmacists’ database and online questionnaires for general practitioners and pharmacists. The collected data has been analysed with the following statistics: descriptive statistics; paired t-test; and Pearson’s correlation coefficient, and analysed through text analyses. Results: The main finding was that medication reviews have a positive influence (p < 0.05) on the average decrease in number of drugs, and in number of potentially inappropriate drugs that patients use. The average number of drugs a patient used one day before the review was 8.7 (sd = 2.9), which decreased to 8.3 (sd = 2.7) drugs one week after the review, and to 8.4 (sd = 2.6) drugs three months after the review. The average number of potentially inappropriate drugs was first 0.6 (sd = 0.8) drugs per patient. Both one week and three months after the review it was 0.4 (sd = 0.6) drugs per patient. Additionally, there is positive correlation (p < 0.01) between number of drugs before review and (1) difference in number of drugs before review and one week after review (r = 0.324); (2) difference in number of drugs before review and three months after review (r = 0.321); and (3) number of potential inappropriate drugs before review (r = 0.389). Furthermore, according to general practitioners and pharmacists, medication reviews offer added value to lowering the chance of adverse events, and the contact between them and the patients becomes better. However, performing these reviews is very time-consuming and stressful. Conclusion: This study shows that performing medication reviews in polypharmacy patients is useful to continue. In the short-term and long-term, medication reviews have a positive influence on the prescription policy in the Netherlands.