Purpose: To assess the frequency, timing, patterns and prognostic
significance of change of the syndromic diagnosis in a cohort of newly
diagnosed adults with epilepsy.Method: 180 newly diagnosed adults from an epilepsy centre were
included and followed for 852.4 person years. For each patient, the
syndromic diagnosis was made at entry according to simplified categories.
Changes of the diagnostic categories were then recorded retrospectively
during follow-up. A change of the syndromic diagnosis was
made and dated, based on new data on seizure types and/or EEG findings
and/or neuroimaging results. Using survival analysis, the cumulative
time-dependent probability of change of syndromic category and of
2-year remission was measured. Differences were tested with the logrank
test. A multivariate analysis was performed using Cox\u2019s proportional
hazard function.
Results: The sample included 104 men and 80women aged 15 through
84 years. At entry, 61 patients (33.9%) had partial epilepsies, 42 (23.3%)
had generalised epilepsies, 19 (10.6%) had undetermined epilepsies,
and 58 (32.2%) had isolated seizures. The syndromic diagnosis was
changed during follow-up in 54 cases (30%). The cumulative probability
of change was 10% at six months, 16%, 19%, and 25% at 12, 24,
and 36 months. 83% of changes were in patients with isolated seizures
who relapsed (45 cases). A total of 105 patients (58.3%) achieved 2-year
remission. The cumulative probability of remission was similar when
comparing patients with and without change of the syndromic diagnosis
(log-rank 0.11; p = ns), after excluding those with isolated seizures at
entry, and when adjusting for age, sex, disease duration at entry, and
treatment in the multivariate analysis model.
Conclusion: Except for isolated seizures, the syndromic diagnosis at
entry changed infrequently (mostly during the first year) in adults and
did not affect the chance of long-term remission of epilepsy