(132) Polypharmacy and Potentially Inadequate Medication in Older Adults: Results from the German National Cohort (NAKO) Baseline.

Background: Polypharmacy and potentially inadequate medication (PIM) are important risk factors for adverse drug reactions especially in older adults.

Objectives: To investigate the prevalence of polypharmacy and PIM use in older adults participating in the NAKO baseline.

Methods: We included 28,807 (49.2% female) persons participating in the baseline examination (2014-2019) of the German National Cohort study (NAKO) who were 65 years or older at the time of their baseline visit. Medication use was assessed by computer-assisted, face-to-face interviews. Participants were asked to bring packages of the medications they used in the past seven days. Based on the pharmaceutical identification number (PZN) and a database-supported identification system detailed information (e.g. ATC code, strength) was recorded for each medication. In the interview, information was collected for each medication regarding the number of tablets per day, the duration of use, the frequency of use (regularly or as needed) and whether it was prescribed by a physician. We calculated the proportions of participants with polypharmacy (i.e. using five or more medications) and the proportions of participants using PIMs (defined by the German PRISCUS list) stratified by sex. Additionally, the anticholinergic burden of participants was assessed using the German ACB list.

Results: Polypharmacy was present in 33.6% [95% CI 32.8%;34.3%] of women and 31.3% [30.5%;32.0%] of men. When focusing on prescribed medications only (N = 28,670 due to missing information on prescription status), polypharmacy was present in 21.7% [21.1%;22.4%] of women and 25.4% [24.7%;26.1%] of men. Participants with polypharmacy reported that they used on average 7.2 (SD 2.4) drugs in the past seven days. Use of at least one medication listed on the PRISCUS list was reported by 6.4% [6.1%;6.9%] of women and 4.6% [4.3%;4.9%] of men. PIMs used by the participants were mostly prescribed by a physician. Psychoanaleptics and non-steroidal anti-inflammatory drugs were the most commonly used PIMs. Medicines with anticholinergic properties were used by 28.8% [28.1%;29.6%] of women and 28.0% [27.2%;28.7%] of men. An anticholinergic burden score of two or more was observed in 11.6% [11.1%;12.2%] of women and 9.0% [8.6%;9.5%] of men. Almost all medications with anticholinergic properties were prescribed by physicians.

Conclusions: Polypharmacy and use of drugs with anticholinergic burden was common among older NAKO participants. This could indicate opportunities for improvement in the prescription and use of medication. However, it should be noted that the NAKO study is not representative for the German population and our findings should be confirmed in population representative samples.