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Henry Klein, MD, MOH

Lt Col, USAF, MC, FS

USAF School of Aerospace Medicine

WPAFB, OH

RAM 2013

Incidence of Post-Traumatic Incidence of Post-Traumatic Epilepsy after Traumatic Brain Epilepsy after Traumatic Brain

Injury in AviatorsInjury in Aviators

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Disclosure InformationDisclosure Information84th Annual Scientific Meeting84th Annual Scientific Meeting

Dr. Henry KleinDr. Henry Klein

I have no financial relationships to disclose.

I will not discuss off-label use and/or investigational use in our presentation.

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• Affects an estimated 1800 airmen each year• Risk adverse neuropsychological

consequences or post traumatic epilepsy • Mild – low risk

Background on TBIBackground on TBI

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• Few long term studies for the risk of PTE• Risk varies with clinical severity of injury

Post traumatic epilepsy (PTE)Post traumatic epilepsy (PTE)

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• Risk is highest in the first year – 100 fold• Still 20 fold after 5 years

* Severe

Post traumatic epilepsy (PTE) *Post traumatic epilepsy (PTE) *

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• Risk higher among subgroups • Intracranial bleeding• Subdural hematoma

Post traumatic epilepsy (PTE)Post traumatic epilepsy (PTE)

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Seizure Incidence by SeveritySeizure Incidence by Severity

Annegers. N Engl J Med 1998;338:20-4

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• At present, the population based data seems the most appropriate for comparison to risks for PTE in aviators.

• Airmen – healthier group than general population

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• Incidence of PTE in Aviators = Incidence of PTE in the general population

Null HypothesisNull Hypothesis

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• All FAA applicants for a medical certificate in the last 10 years that had a diagnosis of syncope or unconsciousness in the past medical history

• 4845 subjects

SelectionSelection

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Total Class 1 reviewed 725

Total Class 3 reviewed 320

Total records reviewed 1045

Records ReviewedRecords Reviewed

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TBI in class 1 131

TBI in class 3 14

Total TBI 145

Records positive for TBIRecords positive for TBI

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MILD MODERATE SEVERE

LOC or amnesia < 30’ LOC or amnesia > 30’ but< 24 hours or skull fracture

LOC or amnesia > 24 hours or presence of subdural hematoma or brain contusion

ClassificationClassification

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Class 1 Class 3 Person-years

Mild 100 6 1140

Moderate 6 0 56

Severe 25 8 381

ResultsResults

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TBI with seizures * TBI with seizures *

Class 1 1 Seizures for 3 months after TBI then no seizures. Followed for 29 years

Class 3 1 Seizures for 2 years then no seizures for 20 years.

Followed for 20 years

Total with Seizures 2

* All severe TBI

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severity Incidence Lower 95% ci Upper 95% ci

Mild or Moderate 0% 0% 3.6%

Severe 6.1% 1% 22%

Total 1.5% 0.2% 3.1%

ResultsResults

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• Consistent with civilian population data• No evidence for a “healthy airman” effect• Administrative data base as currently set up

cannot be used for surveillance or for monitoring of appropriateness of policy.

DiscussionDiscussion

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QUESTIONS?

THE ENDTHE END

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Seizure risk (%) by time Seizure risk (%) by time Severe injurySevere injury

3