Paramedic PapersHome Cardiac arrest Unwitnessed arrests: mostly women, mostly at home
Cardiac arrest
Unwitnessed arrests: mostly women, mostly at home
Determinants of unwitnessed out-of-hospital cardiac arrest: a systematic review (HL-D-26-00618)
Heart & Lung · 2026-10-08 · Added 10 October 2026
A systematic review of 22 studies (210,028 people) found female sex and arrest at home were the most consistent determinants of unwitnessed OHCA, with weaker, mostly unadjusted evidence for night or sleep arrests, deprivation and psychiatric illness.
- Study type
- Systematic review
- Design
- Systematic review
- Participants
- 22 studies, 210,028 adults
- Main finding
- Female sex and home location most consistently associated with unwitnessed arrest; limited evidence for arrests at night or during sleep, low socioeconomic status, type I diabetes and psychiatric illness
- Caveat
- Much of the included evidence came from unadjusted analyses with heterogeneous definitions of witnessed status
- Bottom line
- Context only
Why it matters in Australia (High relevance). The determinants are population and household factors, not features of a particular EMS system, so the pattern travels directly to Australian communities.
Learning goal
Recognise which patients are most likely to sustain an unwitnessed cardiac arrest and how this shapes response priorities.
More
- Topic: Cardiac arrest
- Daily scan: 10 October 2026
- Podcast: Paramedic Papers Daily, 10 October 2026
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