ApoE epsilon4 allele and disease duration affect verbal learning in mild temporal lobe epilepsy

Epilepsia. 2005 Jan;46(1):110-7. doi: 10.1111/j.0013-9580.2005.15804.x.

Abstract

Purpose: To clarify the possible role of other factors including the ApoE epsilon4 allele for memory decline in temporal lobe epilepsy (TLE).

Methods: We conducted a neuropsychological and molecular study in 138 consecutive patients (78 female patients; mean age, 50.2 years, SD +/- 17.9; range, 14 to 87 years) with mild nonlesional TLE, who rarely or never had seizures at long-term follow-up. The mean age at seizure onset was 33.0 years (SD, +/-21.7), and the mean duration of epilepsy was 17.1 years (SD, +/-15.7).

Results: Thirty-four (25%) of 138 patients had test scores indicating verbal learning deficit (VLD). The presence of an ApoE epsilon4 allele was associated with an increased risk of VLD (OR, 4.18; 95% CI, 1.66-10.55). The effect of the ApoE genotype was independent of both the age at epilepsy onset and disease duration as well as of a low educational level, which were separately associated with VLD (p values = 0.045, 0.001, and 0.001, respectively). A significant linear trend (p = 0.005) was seen in the relation between disease duration and cognitive impairment, with the highest risk being in patients with an epilepsy duration > or =25.5 years (OR, 7.06; 95% CI, 1.67-29.85), especially if they carried the epsilon4 allele (OR, 32.29; 95% CI, 5.23-195.72).

Conclusions: These results provide evidence for an alteration in cognitive performance as a function of the presence of the ApoE epsilon4 allele and point to the critical role of disease duration itself for cognitive impairment in TLE.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Aged
  • Apolipoprotein E4
  • Apolipoproteins E / genetics*
  • Cognition Disorders / diagnosis*
  • Cognition Disorders / genetics
  • Educational Status
  • Epilepsy, Temporal Lobe / diagnosis
  • Epilepsy, Temporal Lobe / genetics*
  • Female
  • Genetic Predisposition to Disease
  • Genetic Testing
  • Humans
  • Male
  • Middle Aged
  • Neuropsychological Tests*
  • Psychiatric Status Rating Scales
  • Severity of Illness Index
  • Verbal Learning / physiology*

Substances

  • Apolipoprotein E4
  • Apolipoproteins E