Neonatal seizures: to treat or not to treat?

The immature brain is intrinsically hyperexcitable, a feature that, despite being crucial for learning, synaptogenesis and neuronal plasticity, predisposes the neonate to seizures. Seizures represent the most common neurologic manifestation of impaired brain function in this age group. Importantly, although seizure-induced neuronal injury is minimal in the "healthy" neonatal brain, the "metabolically-compromised" brain appears more vulnerable. Even in the "healthy" brain, however, seizures result in impaired learning, enhanced susceptibility to further seizures, and increased risk of brain injury with seizures later in life, as a result of altered hippocampal circuitry. Given these findings, an aggressive approach to neonatal seizures appears warranted. However, our current conventional therapies (including phenobarbital, phenytoin, and benzodiazepines), even when used in combination, are often ineffective in controlling seizures. Lidocaine may yield better efficacy but requires more study. Recent animal data suggest that alpha-amino-3-hydroxy-5-methyl-4-isoxazole proprionic acid (AMPA) antagonists such as topiramate may have a neuroprotective role. However, further work is needed to confirm the safety of excitatory amino acid antagonists in neonates because there remains a prevailing concern that such agents may impair normal neurodevelopmental processes.     

Enzyme induction with antiepileptic drugs: Cause for concern?

Several commonly prescribed antiepileptic drugs (AEDs)—including phenobarbital, phenytoin, and carbamazepine—stimulate the synthesis of a broad range of monooxygenase and conjugating enzymes. These agents are well known to reduce the duration and action of many lipid‐ and non–lipid‐soluble drugs, including anticoagulants, cytotoxics, analgesics, antiretrovirals, glucocorticoids, statins, antihypertensives, oral contraceptives, psychoactive drugs, immunosuppressants, and of course, other AEDs. This process, therefore, may be associated with a number of clinical problems including higher cancer mortality, progressive AIDS, transplant rejection, and unwanted pregnancy. Withdrawal of enzyme‐inducing AEDs will increase the concentration of induced drugs, bringing with it substantial risk of toxicity if doses are not concomitantly reduced. Yet the potential widespread adverse health consequences of these interactions, both with AED initiation and withdrawal, remain largely underappreciated. Furthermore, induction also affects enzymes involved in endogenous metabolic pathways, and can alter bone biochemistry, gonadal steroids, and lipid markers. Therefore, enzyme‐inducing AEDs may contribute to the development of a number of comorbidities, including osteoporosis, sexual dysfunction, and vascular disease. This process continues as long as the patient takes the inducer. Modern AEDs that do not possess this property have similar efficacy for the common epilepsies. Accordingly, perhaps consideration should be given to starting treatment with, or even switching patients to, non–enzyme‐inducing AEDs.     

Acute symptomatic seizures and hippocampal sclerosis: the major contributor for post-stroke epilepsy?

Journal of Neurology - Hippocampal sclerosis (HS) is a prominent biomarker of epilepsy. If acquired later in life, it usually occurs in the context of degenerative or acute inflammatory-infectious...     

Aggravation of partial seizures by antiepileptic drugs: is there evidence from clinical trials?

OBJECTIVES: To assess clinical trials for evidence that antiepileptic drugs (AED) aggravate partial seizures. To determine if the methodology used to examine drug efficacy can also be used to examine seizure aggravation. BACKGROUND: It is widely accepted that AED aggravate epilepsy in some patients. However, there is little published objective or quantitative evidence. Most reports concern generalized epilepsies. METHODS: Pharmaceutical companies responsible for the development of five of the new AED were asked to provide data concerning seizure increases during randomized placebo-controlled, add-on clinical trials in patients with uncontrolled partial seizures. Seizure frequency in individual patients taking drug or placebo was compared with the baseline pretreatment seizure frequency. The counterpart of the 50% reduction used in efficacy analyses is a 100% increase, because both represent a twofold change. A dose-response relationship was also explored. RESULTS: More than 40% of subjects in clinical trials of tiagabine (TGB), topiramate (TPM), and levetiracetam (LEV) experienced an increase in seizures while taking a placebo. Seizure increases were no more likely to occur when taking any of the three drugs than taking placebo. A doubling or more of seizure frequency was less likely to occur with TPM or LEV than with placebo but more likely with TGB. However, for TGB, this did not reach significance. There was some evidence for a dose-response effect with TGB but a negative effect with TPM (aggravation less likely with increasing dose). Data on gabapentin and lamotrigine were not provided. CONCLUSIONS: Many patients with partial seizures experience an increase in seizures when a new AED is added to their therapy. However, it occurs no more frequently when taking drug than placebo. It probably represents the spontaneous fluctuation of seizure frequency. When a patient who has started a new AED deteriorates, this is not necessarily a drug effect.     

Fatigue during treatment with antiepileptic drugs: A levetiracetam-specific adverse event?

PurposeTo examine the prevalence and clinical correlates of fatigue as an adverse event (AE) of antiepileptic drug (AED) treatment in patients with epilepsy.MethodsData from 443 adult outpatients with epilepsy assessed with the Adverse Event Profile (AEP) and the Neurological Disorder Depression Inventory for Epilepsy (NDDIE) were analysed.ResultsFatigue is reported by 36.6% of patients as always a problem during AED treatment. Fatigue is more likely to be reported by females (64.8% vs. 35.2%; Chi-Square = 16.762; df = 3; p = 0.001) and during treatment with levetiracetam (42.3% vs. 33.2%; Chi-Square = 11.462; df = 3; p = 0.009). The associations with the female gender and levetiracetam treatment were not mediated by depression, as identified with the NDDIE, and could not be simply explained by the large number of subjects on levetiracetam treatment, as analogous figures resulted from the analysis of a monotherapy subsample (41.7% vs. 30.3%; Chi-Square = 11.547; df = 3; p = 0.009).ConclusionsOne third of patients with epilepsy reports fatigue as a significant problem during AED treatment. Fatigue is more likely to be reported by females and seems to be specifically associated with LEV treatment. However, fatigue is not mediated by a negative effect of LEV on mood.     

Hypoactive sexual desire disorder: can we treat it with drugs?

Hypoactive sexual desire disorder (HSDD) is a common multidimensional condition which is characterized by a decrease in sexual desire that causes marked personal distress and/or interpersonal difficulty. There are a number of potential causes and contributing factors to HSDD and a balanced approach comprising both biological and psycho-relational factors is mandatory for accurate diagnosis and tailored management in clinical practice. It is clearly evident that sex hormones play a crucial role in modulating sexual response during the entire reproductive life span of women. On the other hand, a better understanding of the neurobiological basis of sexual desire supports the idea that selective psychoactive agents may be proposed as non-hormonal treatments to restore the balance between excitatory and inhibitory stimuli leading to a normal sexual response cycle. However, there are currently no approved pharmacological treatments for premenopausal women with HSDD, while transdermal testosterone is approved in Europe for post-menopausal women who experience HSDD as a result of a bilateral oophorectomy. That being so, the ideal clinical approach remains to be established in term of efficacy and safety and further research is needed to develop specific pharmacotherapies for individualized care of women with sexual dysfunction of any age.     

A benefit/risk analysis of the prevention of brain ischaemia with anticoagulant drugs: when, how and whom to treat?

This paper summarises the benefits and risks of anticoagulant treatment in patients who have had cerebral ischaemia. In patients with a cardiac source of embolism (in most studies atrial fibrillation), anticoagulation with a target intensity of an INR of 2.0--3.0 is the therapy of first choice. In the case of a contraindication to such treatment, aspirin and ibuprofen are safe, but less effective alternatives. In patients with cerebral ischaemia of presumed arterial origin, anticoagulation with an achieved intensity of 3.0--4.5 proved not to be safe. Results from trials with more moderate anticoagulation regimes are awaited.     

Tolerability of antiepileptic drugs: can we determine differences?

Patient tolerability of adverse effects is integral to successful treatment. Although standard antiepileptic drugs (AEDs) are well tolerated by many patients, the promise of newer AEDs has been the potential for diminished burden of problems with similar seizure control. This report reviews the prevalence of systemic and neurological adverse effects reported in clinical trials of AED monotherapy. A central finding in this report was the unidirectional higher prevalence of selected adverse effects from standard compared with newer AEDs. A system of questioning every patient at every visit to elicit information may be helpful when balancing benefit-to-risk ratio of individualized therapy during everyday practice.     

Mitoxantrone in progressive multiple sclerosis: when and how to treat?

Mitoxantrone (MX) has been approved by the Food and Drug Administration (FDA) for the treatment of patients with worsening relapsing-remitting (RR) or secondary progressive (SP) multiple sclerosis (MS). However, indications should be refined and mitoxantrone reserved as a rescue therapy to: (1) patients in the relapsing-remitting phase with frequent and disabling exacerbations likely leading to permanent severe disability and (2) to patients in the secondary progressive phase whose disability progression rate increases by one EDSS point or more per year and who do not respond to other current therapies. An induction phase with the monthly intravenous administration of 12 mg/m(2) followed by a maintenance phase with 12 mg/m(2) every 3 months for 2 years seems the most effective and safe treatment regimen, not exceeding the maximum cumulative dose of 140 mg/m(2). Given the potent myelosuppressive activity of mitoxantrone, dosage should be carefully adapted to the body surface and hematological changes. Long-term toxicities (amenorrhoea and therapy-related leukemia) seem acceptable but a valid evaluation will need a longer follow-up in more patients. Cardiotoxicity, the major long-term toxicity, is clearly dose-dependent and is a strict treatment duration limiting factor. To reduce the risk of cardiac events, the drug should be administered by slow infusion (over 30 min). Analogs of mitoxantrone with a much lower cardiotoxicity are currently investigated in animal experimental models.     

Prospective audits with newer antiepileptic drugs in focal epilepsy: Insights into population responses?

Despite the availability of a wide range of new antiepileptic drugs (AEDs), there is little evidence that their introduction has substantially altered outcomes. This paper reviews data from 5 consecutive prospective audits with new AEDs using similar methodology. Prospective audits with topiramate (TPM; n = 135), levetiracetam (LEV; n = 136), zonisamide (ZNS; n = 141), pregabalin (PGB; n = 135), and lacosamide (LCM; n = 160) were undertaken in treated patients with uncontrolled partial-onset seizures. Follow-up continued until one of four endpoints was reached: seizure freedom for ≥ 6 months on unchanged dosing; ≥ 50% reduction (responder) in seizure frequency on the highest tolerated dose compared with baseline; < 50% seizure frequency reduction (marginal response) compared with baseline in patients wishing to continue treatment with the new AED; or withdrawal due to lack of efficacy, side effects, or both. A greater proportion of seizure-free patients occurred with LEV (23.5%), LCM (21.9%), and TPM (20.7%) than with ZNS (12.8%) and PGB (10.4%). A higher percentage discontinued treatment with ZNS (41.8%) and PGB (50.4%) than with LEV (32.4%), TPM (31.1%), and LCM (22.5%). Most seizure-free patients responded to the new agent as first or second add-on (TPM 96%; LEV 97%; ZNS 89%; PGB 86%; LCM 97%) often at modest or moderate dosing (TPM 68%, ≤ 200 mg/day; LEV 63%, ≤ 1000 mg/day; ZNS 61%, ≤ 100 mg/day; PGB 86%, ≤ 300 mg/day; LCM 74%, ≤ 200 mg/day). With < 10% of patients discontinuing all AEDs due to lack of efficacy, tolerability was the major factor influencing the number of patients remaining on treatment. Lacosamide was the best (77% patients continued treatment), while PGB was the worst (50% continued treatment) tolerated AED. Overall, seizure freedom was achieved in < 25% of patients in each audit, mainly as a first or second add-on, with best tolerated AEDs producing a higher number of good outcomes. Seizures in very few patients with drug-resistant epilepsy, as defined by the International League Against Epilepsy task force, responded to any of the 5 newer AEDs. These data support the suggestion that the introduction of modern agents has not importantly impacted the outcomes in refractory epilepsy.