Age-Related Changes in Hepatic Function: An Update on Implications for Drug Therapy
Joseph L Tan1, Jacques G Eastment1, Arjun Poudel2
1Centre for Research in Geriatric Medicine, School of Medicine, The University of Queensland, Princess Alexandra Hospital, Woolloongabba, Brisbane, QLD, 4102, Australia.
Drugs & Aging
|November 9, 2015
Summary
Aging impairs liver function, affecting drug metabolism and increasing adverse drug reactions in older adults. This review highlights how hepatic changes contribute to frailty and guides appropriate prescribing practices for geriatricians.
Area of Science:
- Geriatric Medicine
- Pharmacology
- Hepatology
Background:
- Aging leads to cumulative deficits, declining organ function, and altered drug pharmacokinetics/pharmacodynamics.
- Liver metabolism is a primary determinant of drug clearance, with age-related hepatic changes significantly impacting medication response in older adults.
- Reduced hepatic detoxification may promote a proinflammatory state, contributing to frailty and exacerbating medication-related issues.
Purpose of the Study:
- To review the impact of age-related hepatic function decline on drug metabolism and response in older individuals.
- To explore the link between impaired liver function, inflammation, frailty, and adverse drug reactions.
- To provide guidance on appropriate prescribing practices for geriatricians, considering hepatic drug metabolism.
Main Methods:
- Literature review focusing on age-related changes in liver size, blood flow, protein binding, and drug-metabolizing enzymes.
- Analysis of how these hepatic changes influence the pharmacokinetics and pharmacodynamics of commonly prescribed medications in older adults.
- Synthesis of information to contextualize appropriate prescribing strategies, including 'start low, go slow' and consideration of drug clearance limitations.
Main Results:
- Age-related decline in hepatic function significantly alters drug metabolism, leading to increased variability in medication response.
- Reduced liver detoxification capacity may contribute to a proinflammatory state, potentially leading to frailty.
- Inflammation further downregulates drug metabolism, increasing the risk of adverse drug reactions and polypharmacy in frail older individuals.
Conclusions:
- Age-related changes in hepatic function are critical determinants of drug response and adverse events in older populations.
- Impaired liver detoxification and associated inflammation can exacerbate frailty and complicate medication management.
- Understanding these hepatic changes is essential for optimizing prescribing practices and improving clinical outcomes in geriatric patients.
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