(099) Individual contributions of medications with anticholinergic side effects to high anticholinergic burden in older adults

Publication Number: 760

Background: Use of medications with anticholinergic side effects can result in a high cumulative anticholinergic burden, which is thought to be associated with worsened cognition and clinical outcomes.

Objectives: To disentangle the individual contributions of different medications with anticholinergic side effects in patients with high anticholinergic burden and identify characteristics associated with different filling patterns.

Methods: We identified patients ≥65 years of age who filled ≥1 medication with anticholinergic side effects in 2019 with a cumulative Anticholinergic Cognitive Burden score (ACB)≥4 (i.e., having a high anticholinergic burden) in a large commercial claims database covering patients in all 50 US states. We classified patients into 3 categories based on how they attained high burden: 1) only filling strongly anticholinergic medications (ACB=2 or 3, "Strong"), 2) only filling lightly anticholinergic medications (ACB=1, "Light"), and 3) filling any combination (“Mixed”). We used multivariable logistic regression to assess the association between prior-year patient characteristics and membership in each of the 3 categories.

Results: In total, 83,286 patients had a high anticholinergic burden; their mean age was 74.3 years (SD:7.1) and 72.9% were women. Of these, 4.5% filled only strong anticholinergics, 4.3% filled light anticholinergics, and the rest 91.2% filled a mix. Patients filling only strong anticholinergics were more likely to be younger (OR:0.94, 95%CI:0.93-0.95), female (OR:1.93, 95%CI:1.67-2.23), healthier (heart failure OR:0.28, 95%CI:0.23-0.33, ischemic heart disease OR:0.45, 95%CI:0.38-0.53, dementia OR:0.73, 95%CI:0.61-0.87, depression OR:0.78, 95%CI:0.68-0.89, hypertension OR:0.62, 95%CI:0.52-0.75) with the exception of diabetes (OR:1.23, 95%CI:1.07-1.42) and hyperlipidemia (OR:1.22, 95%CI:1.05-1.42), had more physicians (OR:1.02, 95%CI:1.01-1.03), and filled fewer medications (OR:0.94, 95%CI:0.92-0.95) compared with those in the light group. Patients filling strong anticholinergics were younger (OR:0.98, 95%CI:0.97-0.98) and female (OR:1.12, 95%CI:1.03-1.21) vs. the mixed group. Patients filling only light anticholinergics were older (OR:1.04, 95%CI:1.03-1.04), male (OR:0.62, 95%CI:0.58-0.67) and had fewer office visits (OR:0.99, 95%CI:0.98-0.99) vs. those filling any combination.

Conclusions: Most US older adults appear to achieve high anticholinergic burden through a combination rather than just strong anticholinergics, with discernable patient characteristics among groups. These insights may help inform interventions to improve prescribing in older adults.