Drug Burden Index and physical function in older Australian men
Article first published online: 25 MAR 2009
© 2009 The Authors. Journal compilation © 2009 The British Pharmacological Society
British Journal of Clinical Pharmacology
Volume 68, Issue 1, pages 97–105, July 2009
How to Cite
Gnjidic, D., Cumming, R. G., Le Couteur, D. G., Handelsman, D. J., Naganathan, V., Abernethy, D. R. and Hilmer, S. N. (2009), Drug Burden Index and physical function in older Australian men. British Journal of Clinical Pharmacology, 68: 97–105. doi: 10.1111/j.1365-2125.2009.03411.x
- Issue published online: 16 JUL 2009
- Article first published online: 25 MAR 2009
- Received 1 July 2008Accepted18 March 2009
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT
• Inappropriate medication use is common among the elderly.
• Use of medications with anticholinergic and sedative properties is associated with functional impairments in older people.
• Exposure to anticholinergic and sedative medications, measured with Drug Burden Index that includes the principles of dose–response and maximal effect, was associated with impairment in physical and cognitive function in two studies of older people in the USA.
WHAT THIS STUDY ADDS
• We evaluated Drug Burden Index in an Australian population of community-dwelling older men, The Concord Health and Ageing in Men Project that enrolled a random sample of community-dwelling men aged ≥70 years living in Sydney, Australia.
• In this population, increasing Drug Burden Index was associated with objective impairments of physical performance and functional status.
• The Drug Burden Index has broad applicability regardless of healthcare system, prescribing practices, gender or country.
This study evaluated the associations of physical performance and functional status measures with the Drug Burden Index in older Australian men. The Drug Burden Index is a measure of total exposure to anticholinergic and sedative medications that incorporates the principles of dose–response and maximal effect.
A cross-sectional survey was performed on community-dwelling older men enrolled in The Concord Health and Ageing in Men Project, Sydney, Australia. Outcomes included chair stands, walking speed over 6 m, 20-cm narrow walk speed, balance, grip strength and Instrumental Activities of Daily Living score (IADLs).
The study population consisted of 1705 men (age 76.9 ± 5.5 years). Of the 1527 (90%) participants who reported taking medications, 21% were exposed to anticholinergic and 13% to sedative drugs. The average Drug Burden Index in the study population was 0.18 ± 0.35. After adjusting for confounders (sociodemographics, comorbidities, cognitive impairment, depression), Drug Burden Index was associated with slower walking speed (P < 0.05), slower narrow walk speed (P < 0.05), balance difficulty (P < 0.01), grip weakness (P < 0.01) and poorer performance on IADLs (P < 0.05). Associations with physical performance and function were stronger for the sedative than for the anticholinergic component of the Drug Burden Index.
Higher Drug Burden Index is associated with poorer physical performance and functional status in community-dwelling older Australian men. The Drug Burden Index has broad applicability as a tool for assessing the impact of medications on functions that determine independence in older people.