Anticholinergic Burden Measurement in Clinical Pharmacy: Scale Variability, Predictive Validity, and Clinical Utility

Abstract

Anticholinergic burden scores are used in medication review to make cumulative exposure visible, yet the result depends heavily on the scale selected. This critical integrative review examines contemporary evidence on scale variability, predictive validity, and clinical utility in clinical pharmacy. Drug coverage, potency assignment, dose handling, and local formulary adaptation vary substantially across instruments, so the same regimen can move between burden categories without any change in treatment. Higher scores are repeatedly associated with adverse outcomes, although discrimination and calibration are usually more modest than the association literature suggests and depend on the endpoint being studied. Evidence that score-guided deprescribing improves patient outcomes remains limited. Burden measures are therefore most defensible as case-finding or prioritisation tools that direct attention to potentially important exposure. Medication change still requires pharmacological assessment of the contributing drug, its indication, the plausibility of an adverse effect, and the consequences of changing treatment. Cross-scale agreement, predictive validity, and decision-support utility should be reported separately because evidence for one does not establish the others.