Trends in polypharmacy and dispensed drugs among adults in the Netherlands as compared to the United States

Abstract

Background and purposePolypharmacy is becoming increasingly common owing to the ageing population, which can pose problems for patients and society. We investigated the trends in polypharmacy and underlying drug groups among adults in the Netherlands from 1999 to 2014 stratified by age, and compared these with findings from the United States (US).MethodsWe conducted a repeated cross-sectional study using the Dutch IADB.nl prescription database. All patients aged 20 years and older in the period 1999 to 2014 were included. Polypharmacy was defined as the dispensing of five or more chronic drugs at the pharmacological subgroup level. Chi-square tests were applied to calculate the p-value for trends. Changes in prevalences were compared between the Netherlands and the US.ResultsThe prevalence of polypharmacy increased from 3.1% to 8.0% (p-value for trend <0.001) over 15 years, and increased in all age groups. The highest rates were observed in patients aged ≥65 years, but the relative increase over time was higher in the younger age groups. Overall, large increases were observed for angiotensin-II inhibitors, statins and proton-pump inhibitors. The relative increase in polypharmacy was larger in the Netherlands than in the US (ratio of polypharmacy prevalence 2.4 versus 1.8). The Netherlands showed larger relative increases for angiotensin-II inhibitors, statins, proton-pump inhibitors, biguanides and smaller relative increases for antidepressants, benzodiazepines and insulins.ConclusionsPolypharmacy more than doubled from 1999 to 2014, and this increase was not limited to the elderly. The relative increase was larger in the Netherlands compared to the US, which was partly due to larger increases in several guideline-recommended preventive drugs.

Evolution of polypharmacy in a spanish population (2005‐2015): A database study

“…Some studies are based on prescription and others on dispensing . The definition of chronic consumption varies widely (0, 30, 84, 90 days) in comparison with the 180 days of this study. This implies significant variations in the results, although in all cases the prevalence of PP increases over time.…”

“…This implies significant variations in the results, although in all cases the prevalence of PP increases over time. A study in The Netherlands (considering simultaneous prescription of 5 or more medications for at least 90 days in adults aged 20 years and older), reported an increase in PP prevalence from 1999 (3.1%) to 2014 (8%). Another comparable study in a Scottish population also found the prevalence of PP to have doubled between 1995 and 2010 (from 11.4% to 22.1%).…”

“…The present study considered the most widely used definition of PP in order to allow comparisons to be made between different settings based on similar criteria. The results obtained are comparable to those published in other countries, where approximately one out of every three people aged 65 years or older consume 5 or more drugs, and the trends moreover coincide with the evolution of PP reported elsewhere in Europe and the United States …”

“…Although most of the reviewed studies consider PP as the consumption of 5 or more drugs, there is a great methodological variability between publications that makes it difficult to establish detailed comparisons and draw conclusions. Some studies are based on prescription and others on dispensing . The definition of chronic consumption varies widely (0, 30, 84, 90 days) in comparison with the 180 days of this study.…”

“…In populations over 64 years of age, an increase in PP seems to be a general tendency in all comparative studies. Franchi et al reported an increase from 14.9% in 2000 to 28.5% in 2010, similar to that recorded by Oktora et al in The Netherlands, with an increase from 12% in 1999 to 26% in 2014 . However, a recent report by the Organization for Economic Cooperation and Development (OECD) described an almost 3‐fold variation in PP rates in populations over 74 years among 14 countries, analyzing primary care data.…”