PURPOSE No consensus has been reached regarding which anticholinergic scoring system works most effectively in clinical settings. The aim of this populationbased cohort study was to examine the association between anticholinergic medication burden, as defined by different scales, and adverse clinical outcomes among older adults.METHODS From Taiwan's Longitudinal Health Insurance Database, we retrieved data on monthly anticholinergic drug use measured by the Anticholinergic Risk Scale (ARS), the Anticholinergic Cognitive Burden Scale (ACB), and the Drug Burden Index -Anticholinergic component (DBI-Ach) for 116,043 people aged 65 years and older during a 10-year follow-up. For all 3 scales, a higher score indicates greater anticholinergic burden. We used generalized estimating equations to examine the association between anticholinergic burden (ARS and ACB: grouped from 0 to ≥4; DBI-Ach: grouped as 0, 0-0.5, and 0.5-1) and adverse outcomes, and stratified individuals by age-group (aged 65-74, 75-84, and ≥85 years).
RESULTSCompared with the ARS and DBI-Ach, the ACB showed the strongest, most consistent dose-response relationships with risks of all 4 adverse outcomes, particularly in people aged 65 to 84 years. For example, among those 65 to 74 years old, going from an ACB score of 1 to a score of 4 or greater, individuals' adjusted odds ratio increased from 1.41 to 2.25 for emergency department visits; from 1.32 to 1.92 for all-cause hospitalizations; from 1.10 to 1.71 for fracturespecific hospitalizations; and from 3.13 to 10.01 for incident dementia.CONCLUSIONS Compared with the 2 other scales studied, the ACB shows good dose-response relationships between anticholinergic burden and a variety of adverse outcomes in older adults. For primary care and geriatrics clinicians, the ACB may be a helpful tool for identifying high-risk populations for interventions. Ann Fam Med 2017;15:561-569. https://doi.org/10.1370/afm.2131.
INTRODUCTIONM edications with anticholinergic properties are used for a variety of diseases and constitute 30% to 50% of all medications com monly prescribed to older adults. 1 The agingrelated decline of acetylcholine production may increase the vulnerability of older adults to anticholinergic adverse effects, 2,3 such as blurred vision, urinary retention, tachycardia, drowsiness, and cognitive impairments. 4 The blurred vision and dizziness caused by exposure to anticholinergic agents may further result in falls and associated adverse events. 57 The cognitive impairment associated with exposure to these medications may lead to chronic cogni tive deficits such as dementia. 4,8 The cumulative effect of multiple anti cholinergic agents, the socalled anticholinergic burden, has been used as an indicator for suboptimal prescribing in older adults. 9 In recent years, several scoring systems have been developed to quantify anticholinergic burden, such as the Anticholinergic Risk Scale (ARS), 10
562These scales differ considerably in how they were developed, in their method of measuring antich...