Biochemical findings in sudden unexpected death in epilepsy: Hospital based case-control study

PURPOSE

A review study on the biochemistry of epilepsy showed that in epileptic patients, serum glucose and cholesterol concentrations are low, sodium is unaffected, potassium increases, glucose is high and mild hypocalcemia. We have conducted a biochemical study on sudden unexpected death in epilepsy (SUDEP) cases in an attempt to establish the characteristic biochemical values to diagnose these deaths.

METHODS

This was a hospital based case-control study done at All India Institute of Medical Sciences, New Delhi for one year. Twenty SUDEP cases and 20 age- and sex-matched controls were included in the study. Femoral blood, cerebrospinal fluid, vitreous humor, and pericardial fluid were biochemically analyzed for sodium, potassium, calcium, glucose, N-acetyl- cysteine activated creatine kinase (CK-NAC) and isoenzyme CK-MB.

RESULT

Serum sodium, CK-MB and CK-NAC level was found significantly increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths. Likewise, in CSF, sodium and CK-NAC was found increased and potassium level was found decreased in SUDEP cases. In vitreous humor, sodium and CK-MB level was found increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths. In pericardial fluid, sodium, CK-NAC and CK-MB level was found increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths.

CONCLUSION

It concludes that high sodium level and low potassium level could be associated with SUDEP. However, this is a small size study, a larger study is needed to verify the findings. Furthermore, it is difficult to conclude whether these findings are exclusive to SUDEP.

National Association of Medical Examiners Position Paper: Recommendations for the Investigation and Certification of Deaths in People with Epilepsy

Sudden unexpected death of an individual with epilepsy (SUDEP) can pose a challenge to death investigators, as most deaths are unwitnessed and the individual is commonly found dead in bed. Anatomic findings (e.g., tongue/lip bite) are commonly absent and of varying specificity, limiting the evidence to implicate epilepsy as a cause of or contributor to death. Thus, it is likely that death certificates significantly underrepresent the true number of deaths in which epilepsy was a factor. To address this, members of the National Association of Medical Examiners, North American SUDEP Registry, Epilepsy Foundation SUDEP Institute, American Epilepsy Society, and the Centers for Disease Control and Prevention convened an expert panel to generate evidence-based recommendations for the practice of death investigation and autopsy, toxicological analysis, interpretation of autopsy and toxicology findings, and death certification to improve the precision of death certificate data available for public health surveillance of epilepsy-related deaths. The recommendations provided in this paper are intended to assist medical examiners, coroners, and death investigators when a sudden, unexpected death in a person with epilepsy is encountered.

National Association of Medical Examiners position paper: Recommendations for the investigation and certification of deaths in people with epilepsy

Sudden unexpected death of an individual with epilepsy can pose a challenge to death investigators, as most deaths are unwitnessed, and the individual is commonly found dead in bed. Anatomic findings (eg, tongue/lip bite) are commonly absent and of varying specificity, thereby limiting the evidence to implicate epilepsy as a cause of or contributor to death. Thus it is likely that death certificates significantly underrepresent the true number of deaths in which epilepsy was a factor. To address this, members of the National Association of Medical Examiners, North American SUDEP Registry, Epilepsy Foundation SUDEP Institute, American Epilepsy Society, and the Centers for Disease Control and Prevention constituted an expert panel to generate evidence-based recommendations for the practice of death investigation and autopsy, toxicological analysis, interpretation of autopsy and toxicology findings, and death certification to improve the precision of death certificate data available for public health surveillance of epilepsy-related deaths. The recommendations provided in this paper are intended to assist medical examiners, coroners, and death investigators when a sudden unexpected death in a person with epilepsy is encountered.

Implications of Death Certification on Sudden Unexpected Death in Epilepsy (SUDEP) Research

Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death in individuals with chronic, uncontrolled epilepsy. Epidemiologists use information on death certificates to study SUDEP. Certification of seizure-related deaths varies. Multiple classification schemes have been proposed to categorize SUDEP type deaths. Nashef et al. recently proposed categorizing death into Definite SUDEP, Definite SUDEP Plus, Probable SUDEP, Possible SUDEP, Near-SUDEP, and Not SUDEP. This study analyzes certification of seizure-related deaths by our office and considers how it relates to Nashef's classifications. Investigative reports from 2011-2015 from the archives of the Jefferson County Coroner/Medical Examiner's Office were searched for the terms "seizure(s)" and "epilepsy." Cases (N=61) were categorized as Definite SUDEP (n=13), Definite SUDEP Plus (n=12), Probable SUDEP (n=1), Possible SUDEP (n=2), and Not SUDEP (n=33). The term SUDEP was only used in one case of Definite SUDEP. The other 12 cases were certified with variations of terms "seizure" and "epilepsy." Cases categorized as Definite SUDEP Plus were overwhelmingly certified as deaths due to heart disease. Categories Probable SUDEP or Possible SUDEP comprised three cases, and in one of those a seizure-related term was used on the death certificate. Thirty-three cases were classified as Not SUDEP. The finding that the majority of cases of Definite SUDEP were certified as some variation of "seizure" or "epilepsy" but not "SUDEP" has important implications for SUDEP research. Our study also suggests that cases of Definite SUDEP Plus would be difficult for epidemiologists to identify because cardiovascular diseases are more frequently implicated.

The Negative Older Adult Autopsy: Why Do They Die?

Individuals over the age of 65 are a significant segment of the population in the United States and other industrialized countries. This is also the group whose deaths are infrequently investigated or autopsied. However, when an autopsy is performed, the forensic pathologist may be left with final autopsy diagnoses that point to “old age” or “senescence” as the cause of death. This is an unacceptable certification on the death certificate, of no value to epidemiological studies, and of little comfort to the next of kin. Further investigation and analysis must be undertaken to adequately derive an accurate determination of the mechanism, cause, and manner of death. By closely examining and understanding the pathophysiology of three areas/systems, a proper certification can often be made. These areas are the heart, brain, and metabolic/endocrine system.