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Updated: Aug 18, 2026

Observational Study Protocol for Repeated Clinical Examination and Critical Care Ultrasonography Within the Simple Intensive Care Studies
Published on: January 16, 2019
Case-control study of SUDEP
Y Langan1, L Nashef, J W Sander
1Department of Clinical and Experimental Epilepsy, RakeInstitute of Neurology, London, UK.
Objective:
To examine the influence of various factors on the risk of sudden unexpected death in epilepsy (SUDEP).
Methods:
The authors investigated 154 cases in which a postmortem examination was performed. Each case had four controls with epilepsy from the community, matched for age and geographic location. Backward stepwise conditional logistic regression analysis was performed and odds ratios for risk and protection were determined.
Results:
The risk of SUDEP was increased with a history of generalized tonic-clonic seizures in the previous 3 months (odds ratio [OR]: 13.8, 95% CI: 6.6 to 29.1). The presence of supervision at night was found to be protective (OR: 0.4, 95% CI: 0.2 to 0.8) when a supervising individual shared the same bedroom or when special precautions such as a listening device were employed (OR: 0.1, 95% CI: 0.0 to 0.3).
Conclusion:
This work lends support to the view that SUDEP is a seizure-related phenomenon and that control of tonic-clonic seizures is important in its prevention. Nocturnal supervision seems to protect against SUDEP.
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