Associations of drug burden index with falls, general practitioner visits, and mortality in older people
Article first published online: 10 APR 2014
Copyright © 2014 John Wiley & Sons, Ltd.
Pharmacoepidemiology and Drug Safety
Volume 23, Issue 7, pages 753–758, July 2014
How to Cite
Nishtala, P. S., Narayan, S. W., Wang, T. and Hilmer, S. N. (2014), Associations of drug burden index with falls, general practitioner visits, and mortality in older people. Pharmacoepidem. Drug Safe., 23: 753–758. doi: 10.1002/pds.3624
- Issue published online: 4 JUL 2014
- Article first published online: 10 APR 2014
- Manuscript Accepted: 11 MAR 2014
- Manuscript Revised: 2 MAR 2014
- Manuscript Received: 17 SEP 2013
- Drug Burden Index;
- older people;
On a population level in people aged ≥65 years old living in New Zealand, the aim of this study is to quantify each individual's cumulative exposure to anticholinergic and sedative medicines using the Drug Burden Index (DBI) and examine the impact of DBI on fall-related hospitalisations, general practitioner (GP) visits, and all-cause mortality.
The study used data extracted from Pharmaceutical Claims Data Mart (2011), National Minimum Data set (2012), Births, Death and Marriages (2012) and GP Visits (2012) for patient demographics, hospitalisations and mortality. Cumulative anticholinergic and sedative exposure was measured using the DBI. Polypharmacy was defined as greater than or equal to five medicines dispensed concurrently at any time during the study period.
Amongst the study population (n = 537 387; 45% male), 43.22% were exposed to DBI drugs (95% confidence intervals (CIs) = 43.09–43.35). The odds of DBI exposure for individuals with polypharmacy are 4.92 (95%CI = 4.86–4.98) times greater than that for individuals without polypharmacy. DBI drugs were associated with fall-related hospitalisations (incidence rate ratio (IRR) 1.56, 95%CI = 1.47–1.65) and greater number of GP visits (IRR 1.13, 95%CI = 1.12–1.13). Individuals with DBI > 0 had a 1.29 times higher mortality risk (95%CI = 1.25–1.33). Polypharmacy is also associated with a higher mortality risk with a hazard ratio (HR) of 1.66 (95%CI = 1.59–1.73).
Polypharmacy and exposure to DBI drugs were independently associated with fall-related hospitalisations, frequency of GP visits, and risk of mortality. On a population level, DBI may be useful as a quality indicator to guide policy to improve prescribing and optimize clinical outcomes in older people. Copyright © 2014 John Wiley & Sons, Ltd.