Polypharmacy, compliance and non-prescription medication in patients with cardiovascular disease in Germany

Background and objective: The expenses of health insurances are continuously raising. With implementation of evidence-based medicine resulting in polypharmacy, compliance is decreasing and patients as well as physicians are facing unintentional drug interactions. Furthermore the arbitrary use of additional drugs apart from prescribed medication has to be considered. The objective of this study was to analyse polypharmacy, compliance and utilisation patterns for non-prescription medications (OTC) in patients with cardiovascular diseases. Methods: 100 patients with cardiovascular diseases (45 women, 55 men, 58-87 years) were interviewed using a questionnaire. The compliance was determined by the Morisky-Score. Results: 78% of the patients received more than four pills every day (median 8.34). Most common products were beta-blockers (89%), ACE-Inhibitors/Sartans (69%) and aspirin (65%). Only 52% of the patients knew the indications of their medication. Although 83% of the patients claimed to be absolutely compliant concerning their medication, the Morisky-Score revealed a high compliance only in 52%. The compliance decreased significantly if the number of prescribed medication increased to more than four pills a day. 48% of the patients took regularly non-prescription products, 35% more than three additional products daily. Most commonly multivitamins, minerals, herbals and non-steroidal anti-inflammatory drugs were used. This non-prescription medication did not affect the compliance of the patients. Conclusions: Polypharmacy with more than four pills daily leads to a lower compliance and can therefore influence the implementation of guideline-medicine. Non-prescription medication is widely used and should be considered because of their potential side-effects and drug interactions.