Summary of findings 2. Topiramate compared with carbamazepine for epilepsy (secondary outcomes).
| Topiramate compared with carbamazepine for epilepsy (secondary outcomes) | ||||||
|
Population: adults and children with newly onset focal or generalised epilepsy Settings: outpatients Intervention: topiramate Comparison: carbamazepine | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No. of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Carbamazepine | Topiramate | |||||
|
Time to first seizure after randomisation All participants Range of follow‐up: 0 to 2420 days |
The median time to first seizure after randomisation was 154 days in the carbamazepine group | The median time to first seizure after randomisation was 124 days (30 days shorter) in the topiramate group | HR 1.11 (0.96 to 1.29)a |
1115 (2 studies) |
⊕⊕⊕⊕ High | HR < 1 indicates a clinical advantage for topiramate |
|
Time to first seizure after randomisation Subgroup: focal onset seizures Range of follow‐up: 0 to 2420 days |
The median time to first seizure after randomisation was 95 days in the carbamazepine group | The median time to first seizure after randomisation was 90 days (5 days shorter) in the topiramate group | HR 1.12 (0.95 to 1.31) |
925 (2 studies) |
⊕⊕⊕⊕ High | HR < 1 indicates a clinical advantage for topiramate |
|
Time to first seizure after randomisation Subgroup: generalised onset tonic‐clonic seizures or unclassified epilepsy Range of follow‐up: 0 to 853 days |
The median time to first seizure after randomisation was 495 days in the carbamazepine group | The median time to first seizure after randomisation was 393 days (102 days shorter) in the topiramate group | HR 1.08 (0.70 to 1.66) |
190 (2 studies) |
⊕⊕⊕⊝ Moderateb | HR < 1 indicates a clinical advantage for topiramate |
|
Time to 12‐month remission of seizures All participants Range of follow‐up: 0 to 2420 days |
The median time to achieve 12‐month remission was 484 days in the carbamazepine group | The median time to achieve 12‐month remission was 537 days (53 days longer) in the topiramate group | HR 0.84 (0.71 to 0.99)a |
1115 (2 studies) |
⊕⊕⊕⊕ High | HR < 1 indicates a clinical advantage for carbamazepine |
|
Time to 12‐month remission of seizures Subgroup: focal onset seizures Range of follow‐up: 0 to 2420 days |
The median time to achieve 12‐month remission was 533 days in the carbamazepine group | The median time to achieve 12‐month remission was 582 days (49 days longer) in the topiramate group | HR 0.82 (0.69 to 0.99) |
925 (2 studies) |
⊕⊕⊕⊕ High | HR < 1 indicates a clinical advantage for carbamazepine |
|
Time to 12‐month remission of seizures Subgroup: generalised onset tonic‐clonic seizures or unclassified epilepsy Range of follow‐up: 0 to 853 days |
The median time to achieve 12‐month remission was 365 days in the carbamazepine group | The median time to achieve 12‐month remission was 365 days (0 days longer) in the topiramate group | HR 0.92 (0.61 to 1.41) |
190 (2 studies) |
⊕⊕⊕⊝ Moderateb | HR < 1 indicates a clinical advantage for carbamazepine |
| *Illustrative risks in the topiramate and carbamazepine groups are calculated at the median time to first seizure or time to 12‐month remission (i.e. the time to 50% of participants experiencing a first seizure or 12‐months of remission) within each group across all trials. The relative effect (pooled hazard ratio) shows the comparison of 'time to first seizure' or 'time to 12‐month remission' between the treatment groups. CI: confidence interval; HR: hazard ratio | ||||||
| GRADE Working Group grades of evidence High certainty: further research is very unlikely to change our confidence in the estimate of effect Moderate certainty: : further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate Low certainty: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate Very low certainty: we are very uncertain about the estimate | ||||||
aPooled HR for all participants adjusted for seizure type. bDowngraded once for imprecision and applicability, limited information on generalised seizure types and most participants do not have a classified seizure type in this subgroup so the interpretation of this seizure type is unclear.