Polypharmacy: Definition, Epidemiology, Consequences and Solutions

Increasing multimorbidity in an ageing population has led to a rise in the prevalence of polypharmacy throughout the developed world. In many cases, polypharmacy is justified and reflects the increased range of therapeutic options modern medicine can offer. However, ageing is associated with physiological changes affecting drug pharmacokinetics and pharmacodynamics. Complex combinations of multiple medications in multimorbid older adults lead to drug–drug interactions, drug–disease interactions and an increased risk of adverse outcomes. It is important to differentiate between appropriate and inappropriate polypharmacy; the latter is associated with geriatric syndromes including falls, immobility, fractures, cognitive impairment and frailty as well as excess hospitalisation and mortality. Inappropriate polypharmacy is also associated with prescribing errors and non-adherence and represents a major avoidable economic cost to society. By addressing this problem, prescribers can reduce an older person’s risk of adverse drug events, reduce medication burden, enhance the treatment of comorbidities and decrease costs for both the patient individually and the society generally. Medication review is a key component of comprehensive geriatric assessment and should follow the same systematic, holistic, multidisciplinary approach whilst simultaneously taking account of the patient’s wishes. Tools such as STOPP/START can identify potentially inappropriate medications that should be discontinued or medications that are likely to provide benefit to the patient and should be initiated.