Table 2.
Evidence supporting the association of the Drug Burden Index with outcomes: cross-sectional and longitudinal studies categorized by participant setting
| Study setting, population age | Country (n) | Prevalence % DBI >0 or mean (± SD) DBI score | DBI association with outcomes | Resource used to identify minimum effective dose (δ) of medications |
|---|---|---|---|---|
| Cross-sectional, community-dwelling older adults | ||||
| 70–79 years | USA (3,075) | 0.18±0.35 | DBI was associated with poorer physical function and cognition12 | FDA |
| ≥70 years91,* | Australia (1,705) | 0.18±0.35 | Higher DBI was associated with poorer physical performance and functional status24 | TGA |
| ≥70 years91,* | Australia (1,662) | Robust 20.1% Pre frail 29.7% Frail 45.5% |
Higher DBI may contribute to frailty27 | TGA |
| ≥70 years91,* | Australia (987) | 27.8% | DBI was not associated with limitations on objective cognitive measures or with cognitive impairment32 | TGA |
| ≥75 years | Finland (700) | 36.7% | DBI was associated with functional impairment25 | Pharmaca Fennica |
| ≥75 years | Finland (339) | 37.5% | Exposure to DBI medications was associated with a greater use of hospital days83 | Pharmaca Fennica |
| Admitted to geriatric medicine units, >60 years | UK (362) | Median (IQR) 0.48 (0.00–1.00) |
Higher DBI scores on admission were independently associated with length of hospital stay and lower scores in functional measures84 | BNF |
| Cross-sectional, residential aged care or hospitalized older adults | ||||
| ≥70 years | Australia (602) | 69.9% | DBI was only associated with impairment in balance and not with physical function26 DBI was significantly and independently associated with falls in older people29 High exposure to DBI medications showed no significant association between increased DBI and mortality30 |
TGA sourced from MIMS85 |
| ≥70 years | Australia (115) | 0.24±0.40 | DBI was associated with impairments in physical functioning23 | TGA |
| ≥65 years | The Netherlands (71) | Median (range) for ACh component 0.00 (0.00–1.75) |
ACh-DBI was significantly associated with 3-month and one-year mortality18 | BNF |
| ≥65 years | Australia (226) | 78.8% | A DBI >0 was associated with poorer self-reported quality of life outcomes86 | N/A |
| ≥65 years50,** | USA (112) | N/A | High DBI scores were associated with poor clinical outcomes and longer lengths of hospital stay50 | Physicians’ Desk Reference22 and product information for individual drugs |
| Longitudinal, community-dwelling | ||||
| 70–79 years | USA (2,172) | 34% At 5 years, 29% |
Increased exposure to high DBI medications was associated independently with lower physical function over 5 years87 | FDA |
| Outpatient clinics, ≥60 years (ACh component of DBI used) | Canada (102) | 0.1±0.2 At one year, 0.6±0.2 |
An increase in the ACh-DBI correlated with poorer delayed memory performance88 | CPS |
| Data extracted from pharmaceutical claims data of older people, ≥65 years | New Zealand (533,129) | 31.8% | Anticholinergic exposure as measured by the ACh-DBI was prominent in the population, even amongst users of acetylcholinesterase inhibitors89 | Medsafe |
| Data extracted from pharmaceutical claims data of older people, ≥65 years | New Zealand (537,387) | 43.2% | Polypharmacy (≥5 medications) was highly associated with DBI exposure. DBI exposure was associated with falls-related hospitalization and greater numbers of GP visits. DBI >0 was associated with higher mortality risk90 | Medsafe |
| Linked data extracted from prescription, special reimbursement, and hospital discharge registers, ≥65 years | Finland (16,603) with AD (16,603) without AD |
51.4% 33.3% |
A dose-response relationship existed between DBI medications and hospitalization and mortality in people with and without AD31 | Pharmaca Fennica |
Notes:
Study conducted as part of Concord Health and Aging in Men Project
this study used a modified DBI calculation for investigating study aims.
Abbreviations: FDA, Food and Drug Administration; TGA, Therapeutic Goods Administration of Australia; GP, general practitioner; MIMS, Monthly Index of Medical Specialties; ACh, anticholinergic; DBI, Drug Burden Index; N/A, not available; AD, Alzheimer’s disease; BNF, British National Formulary of the British Medical Association and the Royal Pharmaceutical Society; Pharmaca Fennica, source of Finnish registered medication product information; CPS, Compendium of Pharmaceuticals and Specialities from the Canadian Pharmacists Association; Medsafe, source of New Zealand product safety data sheets; IQR, interquartile range; SD, standard deviation.