Contraceptive vaginal ring reduces lamotrigine levels

OBJECTIVE

The objective of the study was to describe the effect of the vaginal ring and transdermal patch on lamotrigine serum levels in women with epilepsy.

BACKGROUND

Previous studies demonstrate that oral hormonal contraceptives containing synthetic estrogen increase lamotrigine clearance through induction of glucuronidation. This leads to variable lamotrigine serum concentrations throughout monthly cycles in women who are on combined oral contraceptives (COCs). The effects of estrogen-containing nonoral hormonal contraceptive methods, including the vaginal ring and transdermal patch, on lamotrigine pharmacokinetics are not well described.

METHODS

Retrospective chart review was performed to identify serum lamotrigine levels drawn from women with epilepsy while on the active phase of vaginal ring or transdermal patch and while off contraception. Wilcoxon signed-rank tests for paired data were used to compare the difference in dose-corrected lamotrigine concentration in plasma between values while on hormonal contraception to those while off contraception in patients using a vaginal ring.

RESULTS

Six patients were using the vaginal ring, and one patient was using the transdermal patch. Lamotrigine dose-corrected concentrations were decreased during the active phase of the vaginal ring compared with concentrations during the period off contraception (p = .04). There was one patient without a decrease in concentration, but the other five patients on the vaginal ring had a decrease in dose-corrected lamotrigine concentration ranging from 36 to 70% while on the vaginal ring. Similarly, one patient using the transdermal patch had a decrease of 37% in dose-corrected lamotrigine concentration while on the patch.

CONCLUSIONS

The findings support that the vaginal ring contraceptive method decreases lamotrigine concentrations during the active phase of treatment. This has important implications for contraceptive counseling and maintaining therapeutic levels in women of childbearing age with epilepsy.

Interictal Epileptiform Discharge Detection in EEG in Different Practice Settings

OBJECTIVE

The goal of the study was to measure the performance of academic and private practice (PP) neurologists in detecting interictal epileptiform discharges in routine scalp EEG recordings.

METHODS

Thirty-five EEG scorers (EEGers) participated (19 academic and 16 PP) and marked the location of ETs in 200 30-second EEG segments using a web-based EEG annotation system. All participants provided board certification status, years of Epilepsy Fellowship Training (EFT), and years in practice. The Persyst P13 automated IED detection algorithm was also run on the EEG segments for comparison.

RESULTS

Academic EEGers had an average of 1.66 years of EFT versus 0.50 years of EFT for PP EEGers (P < 0.0001) and had higher rates of board certification. Inter-rater agreement for the 35 EEGers was fair. There was higher performance for EEGers in academics, with at least 1.5 years of EFT, and with American Board of Clinical Neurophysiology and American Board of Psychiatry and Neurology-E specialty board certification. The Persyst P13 algorithm at its default setting (perception value = 0.4) did not perform as well at the EEGers, but at substantially higher perception value settings, the algorithm performed almost as well human experts.

CONCLUSIONS

Inter-rater agreement among EEGers in both academic and PP settings varies considerably. Practice location, years of EFT, and board certification are associated with significantly higher performance for IED detection in routine scalp EEG. Continued medical education of PP neurologists and neurologists without EFT is needed to improve routine scalp EEG interpretation skills. The performance of automated detection algorithms is approaching that of human experts.

Counseling by epileptologists affects contraceptive choices of women with epilepsy

INTRODUCTION

There are several important interactions between antiepileptic drugs (AEDs) and hormonal contraception that need to be carefully considered by women with epilepsy (WWE) and their practitioners. Many AEDs induce hepatic enzymes and decrease the efficacy of hormonal contraception. In addition, estrogen-containing hormonal contraception can increase the metabolism of lamotrigine, the most commonly prescribed AED in women of childbearing age. The intrauterine device (IUD) is a highly effective form of reversible contraception without AED drug interactions that is considered by many to be the contraceptive of choice for WWE. Women with epilepsy not planning pregnancy require effective contraceptive counseling that should include discussion of an IUD. There are no guidelines, however, on who should deliver these recommendations. The objective of this study was to explore the hypothesis that contraceptive counseling by a neurologist can influence the contraceptive choices of WWE. In particular, we explored the relationship between contraceptive counseling in the epilepsy clinic and the likelihood that patients would obtain an IUD.

METHODS

We conducted a retrospective chart review of female patients age 18-45 seen at our institution for an initial visit between 2010 and 2014 to ascertain the type of contraceptive counseling each patient received as well as AED use and contraceptive methods. Patients who were pregnant or planning pregnancy at the first visit were excluded from further analyses as were patients with surgical sterilization. We also examined a subgroup of 95 patients with at least 4 follow-up visits to evaluate the efficacy of epileptologists' counseling. Specifically, we looked at the likelihood a patient obtained an IUD based on the type of counseling she had received. Fisher exact tests assessed associations between counseling type and whether patients had obtained an IUD.

RESULTS

Three hundred and ninety-seven women met criteria for inclusion. Only 35% of female patients were counseled about contraception at the first visit. If women were not counseled at the first visit, they were unlikely to be counseled at subsequent visits; only 37% had ever received counseling by their fourth visit. Of the 95 patients who completed 4 visits, 28.4% were counseled about an IUD as an optimal contraceptive choice, 38.9% were generally counseled about contraceptive interactions, and 32.6% were not counseled about contraception. Women with epilepsy who received IUD-specific counseling were significantly more likely to switch to an IUD (44.4%) compared with women who received no contraceptive counseling (6.5%; p=0.0009). Women with epilepsy who received IUD-specific counseling also tended to switch to an IUD more often than those women receiving general counseling about AEDs and contraceptive interactions (18.9%; p=0.027). There was no significant difference in the likelihood of acquiring an IUD between the general counseling and no counseling groups.

CONCLUSIONS

Contraceptive counseling by epileptologists and specific mention of an IUD is significantly associated with patient selection of an IUD as a contraceptive method. This suggests that neurologists can play an important role in patients' contraceptive choices.

"Ictal" lateralized periodic discharges

OBJECTIVE

Whether lateralized periodic discharges (LPDs) represent ictal or interictal phenomena, and even the circumstances in which they may represent one or the other, remains highly controversial. Lateralized periodic discharges are, however, widely accepted as being ictal when they are time-locked to clinically apparent symptoms. We sought to investigate the characteristics of "ictal" lateralized periodic discharges (ILPDs) defined by time-locked clinical symptoms in order to explore the utility of using this definition to dichotomize LPDs into "ictal" and "nonictal" categories.

METHODS

Our archive of all continuous EEG (cEEG) reports of adult inpatients undergoing prolonged EEG monitoring for nonelective indications between 2007 and 2011 was searched to identify all reports describing LPDs. Lateralized periodic discharges were considered ILPDs when they were reported as being consistently time-locked to clinical symptoms; LPDs lacking a clear time-locked correlate were considered to be "nonictal" lateralized periodic discharges (NILPDs). Patient charts and available neuroimaging studies were also reviewed. Neurophysiologic localization of LPDs, imaging findings, presence of seizures, discharge outcomes, and other demographic factors were compared between patients with ILPDs and those with NILPDs. p-Values were adjusted for false discovery rate (FDR).

RESULTS

One thousand four hundred fifty-two patients underwent cEEG monitoring at our institution between 2007 and 2011. Lateralized periodic discharges were reported in 90 patients, 10 of whom met criteria for ILPDs. Nine of the patients with ILPDs demonstrated motor symptoms, and the remaining patient experienced stereotyped sensory symptoms. Ictal lateralized periodic discharges had significantly increased odds for involving central head regions (odds ratio [OR]=11; 95% confidence interval [CI]=2.16-62.6; p=0.018, FDR adjusted), with a trend towards higher proportion of lesions involving the primary sensorimotor cortex (p=0.09, FDR adjusted).

CONCLUSIONS

When defined by the presence of a time-locked clinical correlate, ILPDs appear to be strongly associated with a central EEG localization. This is likely due to cortical irritability in central head regions having greater propensity to manifest with positive, clinically apparent, and time-locked symptoms. Thus, dichotomization of ILPDs and NILPDs on this basis principally reflects differences in underlying anatomical locations of the periodic discharges rather than providing a clinically salient categorization.

Ictal sensory periodic lateralized epileptiform discharges

We describe the case of a 74-year-old man with left parietal arteriovenous malformation (AVM) and cerebral white matter radiation necrosis who developed persistent subjective right-sided groin pulsations. The EEG revealed left parietal periodic lateralized epileptiform discharges (PLEDs) time-locked to these sensations, confirming that the patient's symptoms represented sensory seizures with ictal PLEDs as the electrographic correlate. To our knowledge, this is the first reported case of ictal PLEDs manifesting as sensory seizures.

Anticonvulsant use and outcomes after intracerebral hemorrhage

BACKGROUND AND PURPOSE

There are few data on the effectiveness and side effects of antiepileptic drug therapy after intracerebral hemorrhage. We tested the hypothesis that antiepileptic drug use is associated with more complications and worse outcome after intracerebral hemorrhage.

METHODS

We prospectively enrolled 98 patients with intracerebral hemorrhage and recorded antiepileptic drug use as either prophylactic or therapeutic along with clinical characteristics. Antiepileptic drug administration and free phenytoin serum levels were retrieved from the electronic medical records. Patients with depressed mental status underwent continuous electroencephalographic monitoring. Outcomes were measured with the National Institutes of Health Stroke Scale and modified Rankin Scale at 14 days or discharge and the modified Rankin Scale at 28 days and 3 months. We constructed logistic regression models for poor outcome at 3 months with a forward conditional model.

RESULTS

Seven (7%) patients had a clinical seizure, 5 on the day of intracerebral hemorrhage. Phenytoin was associated with more fever (P=0.03), worse National Institutes of Health Stroke Scale at 14 days (23 [9 to 42] versus 11 [4 to 23], P=0.003), and worse modified Rankin Scale at 14 days, 28 days, and 3 months. In a forward conditional logistic regression model, phenytoin prophylaxis was associated with an increased risk of poor outcome (OR, 9.8; 1.4 to 68.6; P=0.02), entering after admission National Institutes of Health Stroke Scale and age. Excluding patients with a seizure did not change the results. Levetiracetam was not associated with demographics, seizures, complications, or outcomes.

CONCLUSIONS

Phenytoin was associated with more fever and worse outcomes after intracerebral hemorrhage.