Seizure diaries for clinical research and practice: limitations and future prospects.

PURPOSE: An NINDS-sponsored conference in April of 2011 reviewed issues in epilepsy clinical trials. One goal was to clarify new electronic methods for recording seizure information and other data in clinical trials. METHODS: This selective literature review and compilation of expert opinion considers advantages and limitations of traditional paper-based seizure diaries in comparison to electronic diaries. KEY FINDINGS: Seizure diaries are a type of patient-reported outcome. All seizure diaries depend first on accurate recognition and recording of seizures, which is a problem since about half of seizures recorded during video-EEG monitoring are not known to the patient. Reliability of recording is another key issue. Diaries may not be at hand after a seizure, lost or not brought to clinic visits. On-line electronic diaries have several potential advantages over paper diaries. Smartphones are increasingly accessible as data entry gateways. Data are not easily lost and are accessible from clinic. Entries can be time-stamped and provide immediate feedback, validation or reminders. Data can also can be graphed and pasted into an EMR. Disadvantages include need for digital sophistication, higher cost, increased setup time, and requiring attention to potential privacy issues. The Epilepsy Diary by epilepsy.com and Irody, Inc. has over 13,000 registrants and SeizureTracker over 10,000, and both are used for clinical and research purposes. Some studies have documented patient preference and increased compliance for electronic versus paper diaries. Seizure diaries can be challenging in the pediatric population. Children often have multiple seizure types and limited reporting of subjective symptoms. Multiple caregivers during the day require more training to produce reliable and consistent data. Diary-based observational studies have the advantages of low cost, allowing locus-of-control by the patient and testing in a "real-world" environment. Diary-based studies can also be useful as descriptive "snapshots" of a population. However, the type of information available is very different from that obtained by prospective controlled studies. The act of self-recording observations may itself influence the observation, for example, by causing the subject to attend more vigilantly to seizures after changing medication. Pivotal anti-seizure drug or device trials still mostly rely on paper-based seizure diaries. Industry is aware of the potential advantages of electronic diaries, particularly, the promise of real-time transmission of data, time-stamping of entries, reminders to subjects, and potentially automatic interfaces to other devices. However, until diaries are validated as research tools and the regulatory environment becomes clearer, adoption of new types of diaries as markers for a primary study outcome will be cautious. SIGNIFICANCE: Recommendations from the conference included: further studies of validity of epilepsy diaries and how they can be used to improve adherence; use and further development of core data sets, such as the one recently developed by NINDS; encouraging links of diaries to electronic sensors; development of diary privacy and legal policies; examination of special pediatric diary issues; development of principles for observational research from diaries; and work with the FDA to make electronic diaries more useful in industry-sponsored clinical trials.

Relative influences of adjunctive topiramate and adjunctive lamotrigine on scanning and the effective field of view.

A subsample of 67 adult patients with partial seizures participating in a randomized, double-blind study comparing the cognitive effects of adjunctive lamotrigine (LTG) and adjunctive topiramate (TPM) was administered Performance On-Line (POL) in addition to a battery of neuropsychological tests at baseline, week 8 and week 16 of treatment. The POL is a self-administered computer task that measures scanning, divided-attention, and the effective field of view. Although the POL does not measure driving performance, POL scores are correlated with driving performance. The results show that adjunctive TPM, but not adjunctive LTG, negatively impacted cognition. Both simple target identification and divided-attention performance on POL were compromised in the TPM group but not in the LTG group. The relative POL impairment associated with chronic TPM treatment was similar to that observed with the acute effects of alcohol with a breath level of .045% or a low dose of alprazolam (0.5mg). Thus, driving-related visual and cognitive skills were compromised by adjunctive TPM treatment. Therapeutic doses of adjunctive TPM pose a potential risk of impaired scanning and divided-attention skills.

Is a separate monotherapy indication warranted for antiepileptic drugs?

Antiepileptic drugs (AEDs) are the only neurotherapeutics for which regulatory approval is consistently separated into monotherapy or adjunctive-therapy indications. Because head-to-head comparisons of AEDs (used in the European Union to approve drugs for monotherapy) have not shown substantial differences in efficacy between drugs, FDA approval for use of an AED as monotherapy has typically been based on trials with novel designs that have been criticised for reasons of ethics and clinical relevance. Many new-generation AEDs have not been approved for monotherapy, causing drug labelling and real-world use to be increasingly inconsistent, with negative consequences for patients. The regulatory requirement for separate monotherapy and adjunctive-therapy indications in epilepsy is unnecessarily restrictive. We recommend that regulatory agencies approve AEDs for the treatment of specific seizure types or epilepsy syndromes, irrespective of concomitant drug use.

The role of the cylooxygenase pathway in nociception and pain.

Cycloxygenase (COX) pathways have long been targeted for the treatment of inflammatory pain, initially through the use of NSAIDs. With the demonstration of two major COX isoforms, COX-1 and COX-2, involved in the production of prostanoids, but with different distribution and regulation, selective COX-2 inhibitors have been developed. This review covers factors influencing COX enzyme activity, the role of their products in the development and maintenance of pain and discusses recent safety concerns of COX-2 inhibitors.

Electrical stimulation of the anterior nucleus of the thalamus for the treatment of intractable epilepsy.

PURPOSE: Animal studies and sporadic case reports in human subjects have suggested that intermittent electrical stimulation of the anterior nucleus of the thalamus reduces seizure activity. We embarked on an open-label pilot study to determine initial safety and tolerability of bilateral stimulation of the anterior nucleus of the thalamus (ANT), to determine a range of appropriate stimulation parameters, and to begin to gather pilot efficacy data. METHODS: We report an open-label pilot study of intermittent electrical stimulation of the anterior nucleus of the thalamus in five patients (three men, two women; age range, 24-47 years), with follow-up between 6 and 36 months. All patients had intractable partial epilepsy. Four of the five patients also had secondarily generalized seizures. Stimulation was delivered by bilateral implantable, programmable devices by using an intermittent, relatively high-frequency protocol. Stimulation parameters were 100 cycles per second with charge-balanced alternating current; pulse width, 90 ms; and voltages ranging between 1.0 and 10.0 V. Seizure counts were monitored and compared with preimplantation baseline. RESULTS: Four of the five patients showed clinically and statistically significant improvement with respect to the severity of their seizures, specifically with respect to the frequency of secondarily generalized tonic-clonic seizures and complex partial seizures associated with falls. One patient showed a statistically significant reduction in total seizure frequency. No adverse events could clearly be attributed to stimulation. None of the patients could determine whether the stimulator was on or off at these parameters. CONCLUSIONS: Electrical stimulation of the ANT appears to be well tolerated. Preliminary evidence suggests clinical improvement in seizure control in this small group of intractable patients. Further controlled study of deep brain stimulation of the anterior nucleus is warranted.