Epidemiological study (observational study)

Mortality and risk of cardiac complications among immediate survivors of accidental electric shock: a Danish nationwide cohort study epidem.

By: Hansen SM, Riahi S, Hjortshøj S, Mortensen R, Køber L, Søgaard P, Torp-Pedersen C

Published in: BMJ Open 2017; 7 (8): e015967

Aim of study (acc. to author)

A nationwide cohort study was conducted in Denmark to investigate whether electric shock patients have an increased risk of developing cardiac disease, cardiac arrhythmias or death compared with the general population.

Endpoint/type of risk estimation

mortality
cardiovascular diseases: acute myocardial infarction, pericarditis, myocarditis, cardiomyopathy, AV block, sick sinus syndrome, supraventricular tachycardia, ventricular tachycardia/fibrillation, atrial fibrillation/flutter, heart failure

Exposure

Assessment

list: electrical shock ICD-10 codes DT754, DT754A, DW85, DW86 and DW87

Population

Group:
- men
- women
Observation period: 1994 - 2011, follow-up until 2012
Study location: Denmark

Case group

Characteristics: patients with diagnosis of electric shock from emergency ward, hospital admission or electric shock as cause of death
Data source: Danish Civil Registration System, Danish National Patient Registry and Danish Register of Causes of Death
Exclusion criteria: struck by lightning, dead at hospital arrival

Control group

Selection:
- population-based
Matching:
- sex
- age
- case:control = 1:5

Study size

	Cases	Controls
Total	11,462	57,310

Statistical analysis method:

Kaplan-Meier estimation
negative binomial regression

Results (acc. to author)

The 5-year cumulative incidence of death was 0.47% (CI 0.29%-0.65%) for emergency ward patients and 1.04% (CI 0.71%-1.37%) for admitted patients. No difference in 5-year survival was observed compared with matched controls. Cardiac procedures (e.g., pacemaker implantation), arrhythmia or cardiac diseases following electric shock were very rare within 30 days as well as from 31 to 365 days. Fewer than four patients received a pacemaker within 30 days.
The authors conclude that the study did not demonstrate an increase in mortality among patients seen at hospitals after accidental electric shock compared with the general population. Cardiac procedures and diseases following electric shock were very rare. The authors suggest that nearly all patients can be discharged safely from the emergency room after electric shock without further observation.

Study funded by

not stated/no funding

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