Examining risk for dementia with benzodiazepines and anticholinergics

  • Grossi CM & al.
  • BMC Geriatr
  • 21 Oct 2019

  • curated by Sarfaroj Khan
  • UK Clinical Digest
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  • This study found no evidence of an increased risk for dementia associated with the use of benzodiazepines (BZD) or anticholinergics with score 1 or 2 (ACB12).
  • However, recurrent use of anticholinergics with score 3 (ACB3) was associated with dementia risk, particularly in those with good baseline cognitive function.

Why this matters

  • Finding suggests that long-term use of anticholinergics should be avoided in older people.

Study design

  • Study used data from the baseline (Y0), 2-year (Y2) and 10-year (Y10) waves of the Medical Research Council Cognitive Function and Ageing Study and included participants with incident dementia cases (n=8216).
  • Use of BZD, ACB3 and ACB12 was coded as:
    • ever use (at baseline or 2-year wave),
    • recurrent use (at baseline and 2-year wave),
    • new use (at 2-year wave, but not baseline) or
    • discontinued use (at baseline, but not 2-year wave).
  • Outcome: incidence of dementia at 10-year wave.
  • Funding: UK Alzheimer’s Society.

Key results

  • At 10 years, overall 220 (9.3%) patients reported dementia incidence.
  • Dementia incidence rate for BZD, ACB3, ACB12 were:
    • 14.5%, 15.4% and 10.5% for ever-users and
    • 16.0%, 18.6% and 10.7% for recurrent users, respectively.
  • At Y10, adjusted incidence rate ratios (IRRs) for dementia were 1.06 (95% CI, 0.72-1.60) for any BZD use, 1.28 (95% CI, 0.82-2.00) for any ACB3 and 0.89 (95% CI, 0.68-1.17) for any ACB12
  • Recurrent use was associated with IRRs of:
    • 1.30 (95% CI, 0.79-2.14) for BZD,
    • 1.68 (95%CI, 1.00-2.82) for ACB3 and
    • 0.95 (95%CI, 0.71-1.28) for ACB12.
  • At 2 years, ACB3 ever-use was associated with an increased risk for dementia among those with Mini-Mental State Examination (MMSE) >25 (IRR, 2.28; 95% CI, 1.32-3.92), but not if MMSE ≤25 (IRR, 0.94; 95% CI, 0.51-1.73).


  • Observational design.
  • Risk of bias.