EPILEPSY

Treatment of Juvenile Myoclonic Epilepsy in Patients of Child-Bearing Potential

Juvenile myoclonic epilepsy (JME) is both a frequent and a very characteristic epileptic syndrome with female preponderance. Treatment of JME in women of childbearing potential must consider multiple factors such as desire for pregnancy, use of contraception, seizure control and previously used antiepileptic drugs (AEDs). Approximately 85% of cases are well controlled with valproate, which remains the reference AED in JME but is nowadays considered unsafe for the expecting mother and her fetus. The prescription of valproate is now severely restricted in women of childbearing potential but may still be considered, at the lowest possible dose and when pregnancies can be reliably planned, with temporary alternatives to valproate prescribed before fertilization. Alternatives have emerged, especially lamotrigine and levetiracetam, but also topiramate, zonisamide, and recently perampanel, but none of these AEDs can be considered fully safe in the context of pregnancy. In special settings, benzodiazepines and barbiturates may be useful. In some cases, combination therapy, especially lamotrigine and levetiracetam, may be useful or even required. However, lamotrigine may have the potential to aggravate JME, with promyoclonic effects. Carbamazepine, oxcarbazepine and phenytoin must be avoided. Valproate, levetiracetam, zonisamide, topiramate if the daily dose is ≤ 200 mg and perampanel if the daily dose is ≤ 10 mg do not affect combined hormonal contraception. Lamotrigine ≥ 300 mg/day has been shown to decrease levonorgestrel levels by 20% but does not compromise combined hormonal contraception. Patients with JME taking oral contraceptive should be counselled on the fact that the estrogenic component can reduce concentrations of lamotrigine by over 50%, putting patients at risk of increased seizures. Pregnancy is a therapeutic challenge, and the risk/benefit ratio for the mother and fetus must be considered when choosing the appropriate drug. Lamotrigine (< 325 mg daily in the European Registry of Antiepileptic Drugs in Pregnancy) and levetiracetam seem to be comparatively safer in pregnancy than other AEDs, especially topiramate and valproate. Plasma concentration of lamotrigine and levetiracetam decreases significantly during pregnancy, and dosage adjustments may be necessary. With persisting generalized tonic-clonic seizures, the combination of lamotrigine and levetiracetam offer the chance of seizure control and lesser risks of major congenital malformations. The risk of malformation increases when valproate or topiramate are included in the drug combination. In one study, the relative risk of autism and autism spectrum disorders (ASD) in children born to women with epilepsy (WWE) treated with valproate were, respectively, 5.2 for autism and 2.9 for ASD versus 2.12 for autism and 1.6 for ASD in WWE not treated with valproate. More studies are needed to assess the risk of autism with AEDs other than valproate. The current knowledge is that the risk appears to be double that in the general population. In patients with JME, valproate remains an essential and life-changing agent. The consequences of a lifetime of poorly controlled epilepsy need to be balanced against the teratogenic risks of valproate during limited times in a woman's life. The management of JME in WWE should include lifestyle interventions, with avoidance of sleep deprivation, and planned pregnancy.

Treatment of epilepsy in postmenopausal women

Menopausal women represent a rapidly growing proportion of the population. Epidemiologic evidence for the increased incidence of epilepsy in elderly patients suggests that with global aging of the population, there is likely to be a growing need for healthcare workers to manage seizures in older women. Unfortunately, there has been relatively little scientific investigation into the unique concerns of postmenopausal woman with epilepsy. There is some evidence that women may experience increased seizure activity during the menopausal transition owing to the effects of estrogen and progesterone on neuronal excitability. During perimenopause and menopause, use of hormone-replacement therapy can also worsen seizure control. Menopausal women are particularly vulnerable to osteoporosis and fragility fractures, both of which demonstrate increased risk following exposure to antiepileptic drugs. Optimization of epilepsy therapy to avoid both seizures and falls caused by antiepileptic drug-induced imbalance is crucial in order to minimize fracture risk in this group of women. Elderly patients are more susceptible to adverse medication side effects owing to drug interactions and the physiologic changes of aging that result in altered drug pharmacokinetics.