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This tool estimates the risk of seizure recurrence and Chance of an Occurrence of a Seizure in the next Year (COSY) following antiseizure medication (ASM) withdrawal in adults with focal epilepsy.  

Variables Used:

• ASM Withdrawal:
  Withdrawal is defined as the planned tapering or cessation of ASMs after at least two years of seizure remission. Cave: Other risk factors should be kept in mind: patients with a shorter seizure-free period (<4 years), a longer history of active epilepsy, or those who underwent rapid tapering faced significantly higher risks of seizure recurrence.

• Time Interval in Months:
  Specifies the months since ASM withdrawal (0–96 months for recurrence risk, 0–60 months for COSY), enabling longitudinal analysis of seizure recurrence probability and dynamic changes in seizure risk.

Outputs:

• Risk of Seizure Recurrence:
  Provides individualized seizure recurrence risk estimates over time.

  • Example: 48.5% of recurrences occur in the first year post-withdrawal, and 79.8% occur within two years. After five years, the recurrence risk drops to below 1%.

• COSY:
  Highlights the dynamic chance in seizure probability in the year following each time point.

  • Example: Patients with longer seizure-free durations before withdrawal show a reduced COSY compared to those with shorter remission periods.