Dementia: meta-analysis of more than 2 million patients finds increased risk from head injury

Access to the full content of this site is available only to registered healthcare professionals. Register to read more


  • Head injury is associated with an increased relative risk (RR) in dementia and Alzheimer's disease (AD).

Why this matters

  • Clinicians should consider the potential for the development of dementia when assessing head injuries.

Key results

  • Researchers included data from 32 studies (total n=2,013,197).
  • Head injury significantly increased the RR for dementia (RR, 1.63) and AD (RR, 1.51). However, both results showed significant heterogeneity between studies.
  • Head injury with loss of consciousness did not show significant increases in relative risk for either dementia or AD.
  • Researchers detected no significant publication bias.

Study design

  • Systematic review and meta-analysis of cohort and case-control studies examining the relationship between head injury and AD.
  • Funding: Jiamusi University.


  • Many studies included relied on self-report.
  • Severity of head injury was not available for all patients.