Epidemiological study of epilepsy in France based on two databases (Epi²)

Study type

• Study topic:
  Disease /health condition
• Study type:
  Non-interventional study
• Scope of the study:
  Disease epidemiology

  Healthcare resource utilisation

  Method development or testing
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Medical condition to be studied:
  Epilepsy

Population studied

• Short description of the study population:
  The initial population to be extracted from the SNDS (French National Health Data System) refers to all individuals, regardless of age (adults and children), identified by the following case selection algorithm: "(patient with at least one antiepileptic drug in outpatient care (DCIR) OR who was hospitalized with a principal diagnosis OR significant associated diagnosis related to epilepsy OR having a long-term illness (ALD) No. 9 severe epilepsy currently in operation – over the following period: 01/01/2017 to 31/12/2019) OR (patient matched to the EDS extraction)". This extraction is intentionally as broad as possible: prescriptions for some antiepileptic drugs may be for indications other than epilepsy (neuropathic pain, anxiety, bipolar disorder, etc.). The idea here is to miss as few epileptic patients as possible and to be able to develop more precise case selection algorithms later on from this population.
• Age groups:
  • In utero
  • Paediatric Population (< 18 years)

    • Neonate

      • Preterm newborn infants (0 – 27 days)
      • Term newborn infants (0 – 27 days)
    • Infants and toddlers (28 days – 23 months)
    • Children (2 to < 12 years)
    • Adolescents (12 to < 18 years)
  • Adult and elderly population (≥18 years)

    • Adults (18 to < 65 years)

      • Adults (18 to < 46 years)
      • Adults (46 to < 65 years)
    • Elderly (≥ 65 years)

      • Adults (65 to < 75 years)
      • Adults (75 to < 85 years)
      • Adults (85 years and over)
• Special population of interest:
  Other
• Special population of interest, other:
  Patients with epilepsy
• Estimated number of subjects:
  600000

Study design details

• Study design:
  Retrospective cohort study
• Main study objective:
  The main objective of the study is to quantify the demand for and the provision of care for patients with epilepsy at the national level
• Setting:
  Extraction of all patients following these criteria:; For the SNDS:; • At least one delivery of an anti-seizure medication; • Or an ICD-10 code for hospitalization or long-term care related to epilepsy (G40 / G41); • Between January 1, 2017, and December 31, 2019.; For the APHP CDW:; • Mention of at least one anti-seizure medication in at least one medical chart; • Or an ICD-10 code for hospitalization related to epilepsy (G40, G41) or a condition that can mimic epilepsy (R53, R55, R56); • Between July 1, 2017, and December 31, 2019.;
• Comparators:
  N/A
• Outcomes:
  For the algorithm targeting patients with epilepsy: sensitivity, specificity, positive predictive value, negative predictive value, F1 score.; For incidence and prevalence: number of patients per 100,000 inhabitants; For care pathways: typical sequences of healthcare consumption and mortality.; For costs: direct and indirect costs (compensation related to work stoppages) in euros.;
• Data analysis plan:
  • Establishing the gold standard from medical reports: natural language processing algorithms comparing rule-based algorithms (automatic detection of negation, hypothesis, and family history) with neural networks.; • Algorithm for targeting epileptic patients in the SNDS: developing rules based on clinical expertise and verifying performance using increasingly sophisticated algorithms.; • Incidence and prevalence: using Poisson regression models to analyze trends over the years.; • Care pathways: using sequence analysis algorithms.; • Costs: using regression methods that account for patient comorbidities to model costs specifically related to epilepsy versus other costs.;
• Summary results:
  N/A