Ageing—along with its associated physiological and pathological changes—places individuals at a higher risk of multimorbidity and treatment-related complications. Today, polypharmacy, a common and important problem related to drug use, occurs subsequent to this multimorbidity in the elderly in all populations. In recent decades, several scientific investigations have studied polypharmacy and its correlates, using different approaches and definitions, and their results have been inconclusive. Differences in definitions and approaches in these studies form a barrier against reaching a conclusion regarding the risk factors and consequences of polypharmacy. It is therefore imperative to establish an appropriate definition of polypharmacy. To read the full article, log in using your NHS OpenAthens details