Strategies to reduce the risk of iatrogenic illness in complex older adults

Abstract
Older patients are particularly vulnerable to adverse drug reactions (ADRs) because age is associated with changes in pharmacokinetics and pharmacodynamics that may alter drug metabolism. In addition, other conditions, commonly observed in older adults, may increase the risk of ADRs in the older population (including polypharmacy, comorbidity, cognitive and functional limitations). ADRs in older adults are frequently preventable, suggesting that screening and prevention programmes aimed at reducing the rate of iatrogenic illness are necessary in this population. The present study reviews available approaches that may be used to screen and prevent the occurrence of ADRs in older adults, including medication review, avoiding the use of potentially inappropriate medications, computer-based prescribing systems and comprehensive geriatric assessment. Available evidence on these approaches is mixed and controversial, and none of them showed a clear beneficial effect on patients' health outcomes. Limitation of these interventions is the lack of standardisation, and these differences may give reason for the variability of the results documented in randomised clinical studies. Interestingly, most of the available research is focused on a single intervention targeting either clinical or pharmacological factors causing ADRs. When these approaches are combined, positive effects on patients health outcomes can be shown, suggesting that integration of skills from different health care professionals is needed to address medical complexity of the older adults. The challenge for future research is to integrate valuable information obtained by existing instruments and methodologies in a complete and global approach targeting all potential factors involved in the onset of ADRs.