Dr George Savva
University of East Anglia
ABCD study: Anticholinergics, Benzodiazepines, Cognition and Dementia
Alzheimer's disease & other dementias
Background and aims: Anticholinergic medications (AChl) and benzodiazepines including Z-drugs (BZD) are commonly used by older people. AChl and BZD impair cognition while they are being used. We will establish whether there is an associated increase in the risk of dementia and whether cognitive impairment persists beyond medication cessation.
Objectives and Methods: We will use data on medication use and cognitive function/dementia from five souces, the Clinical Practice Research Datalink, the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS) 1, MRC CFAS 2, The Irish Longitudinal Study on Ageing and the MRC CFAS neuropathology study. These studies have different strengths and we will use them to estimate:
whether AChl/BZD use increases dementia risk, and how this depends on the level of use
how long any excess risk persists after cessation
whether the risk is restricted to a subgroup of anticholinergic medications, and whether z-drugs differ from benzodiazepines in dementia risk.
how memory and non-memory cognitive domains are affected by duration of current medication use
whether impaired cognition persists, returns to pre-medication levels or continues to decline following medication cessation and how this depends on duration and level of use
neuropathological correlates of AChl/BZD use.
Outcomes: Our findings will contribute to prescribing guidance and practice for management of many common long term conditions. If our findings support an effect of AChl/BZD on dementia, then the benefits and harms of reduction or avoidance of such medication use should be tested as an intervention to reduce dementia incidence.