Changes in seizure severity and quality of life in patients with refractory partial epilepsy.

This 6-month observational, prospective, multicenter study assessed the influence of changes in seizure severity on quality of life in patients with refractory partial epilepsy. Patients (N = 262) diagnosed with partial epilepsy and receiving two antiepileptic drugs as determined by usual clinical practice were enrolled in this study. The primary endpoint was the mean seizure severity score obtained from the Seizure Severity Questionnaire. Reductions in seizure severity were detected from baseline to months 3 and 6 (P<0.0001). Improvements compared with baseline were found for several secondary measures: Hamilton Anxiety and Depression scales (P<0.0001), most Medical Outcomes Study-Sleep subscales (P<0.05), and seven subscales of the Quality of Life in Epilepsy Inventory-31 (QOLIE-31; P<0.0005). Seizure severity correlated directly with anxiety (P<0.0001) and inversely with QOLIE-31 measures (P<0.0001). In conclusion, reducing seizure severity with appropriate medication may lead to improvement in the overall quality of life of patients with refractory partial epilepsy.

Driving cost factors in adult outpatients with refractory epilepsy: a daily clinical practice in clinics of neurology in Spain.

OBJECTIVE: To explore the association between patient-reported-outcomes measurements and costs in adult outpatients with drug refractory epilepsy (DRE) in Spain. METHODS: Secondary analysis of a cross-sectional study to determine resources utilization and related costs of refractory epilepsy in Spain (LINCE study). Consecutive adult outpatients fulfilling criteria for DRE were analyzed. Health-related quality of life (HRQoL), anxiety and depression, self-perceived health status and patient's satisfaction with treatment were assessed respectively by QOLIE-10, HAD scales, EQ-5D-VAS and SATMED-Q questionnaire. Costs were estimated from public tariffs computing healthcare and non-healthcare resources use in the year 2005. RESULTS: Seven hundred sixty two consecutive patients (728 (95.5%) valuables; 50.8% males, 40.5+/-13.5 years) were analyzed. Severe levels of anxiety and depression were both associated with higher costs: from a mean yearly total cost of 6291 euros +/- 7748 (no anxiety) to 10325.8 euros +/-9900.8 (severe), p<0.0012 and from 5983.5 euros +/-6726.1 (no depression) to 12691.4 euros +/-11745.9 (severe), p<0.0001. Total yearly cost was inversely associated with HRQoL, self-perceived health status and satisfaction with treatment: from 11517.3 euros +/-11449.2 to 5430.2 euros +/-7776.6, first and tenth QOLIE-10 decile intervals, respectively, from 11494 euros +/- 11668 to 5334.3 +/- 7606, first and tenth VAS decile intervals, respectively, and from 9762.6 euros +/- 9956.6 to 4746.4 euros +/- 5616.7, first and tenth SATMED-Q decile intervals, respectively, p<0.0001. CONCLUSIONS: Higher costs of refractory epilepsy were associated with poorer patient-reported-outcomes scores. These findings may be of interest for both health decision makers and clinicians when evaluating the resources devoted to epilepsy.

Health and non-health care resources use in the management of adult outpatients with drug-resistant epilepsy in Spain: a cost-of-illness study (LINCE study).

PURPOSE: The purpose of this study was to ascertain health care and non-health care resources use in the past 12-months and to estimate the cost-of-illness in adult outpatients with drug-resistant epilepsy (DRE) in Spain. METHODS: A cross-sectional and retrospective study was designed. Whole nation representative participants (epilepsy and general neurological clinics) were selected at random, but patients with drug-resistant epilepsy were included consecutively. We choose the societal perspective to compute total costs for this study. Estimation of costs was calculated by multiplying unitary costs by number of resources used. RESULTS: Seven hundred sixty-two consecutive patients (50.8% males) with mean (S.D.) age of 40.5 (13.5) years were included. Mean total yearly costs were euro6838 (euro8100) with health costs of euro4977 (euro6490), and indirect costs of euro1618 (euro4527). Gender and severity of seizures were significantly associated with costs; higher in males and subjects with severe seizures. Total annual costs showed a trend toward statistical significant association with age (lower costs in older patients), but costs were unrelated with level of care in Epilepsy or general neurological clinics. DISCUSSION: Health care, and to a lesser extend non-health care resources use, were high in patients with DRE in Spain, yielding a considerable burden to both the National Health System and the Society. Better planning of therapeutic strategies allowing alleviation of load and costs of this health problem should be considered from these findings.

Antiepileptic drug interactions.

INTRODUCTION: Antiepileptics are drugs used in the long-term treatment of epilepsy and other conditions such as pain or psychiatric diseases. They are often administered as polytherapy or in combination with other treatments. It is therefore important to know their potential interactions (with each other and with other substances) in order to avoid altering their efficacy or potentiating their side effects. OBJECTIVE: The purpose of this article is to review these aspects and stress the most important interactions in day-to-day clinical practice. RESULTS: Older antiepileptic drugs (AEDs) such as phenytoin, carbamazepine, phenobarbital and valproic acid can significantly interfere not only with each other and other AEDs, but also with other treatments. Although newer AEDs have a more favourable pharmacokinetic profile, they are not entirely exempt from interactions and they are also commonly administered in combination with older AEDs. Another aspect that should be considered is the existence of any clinically important pharmacokinetic and pharmacodynamic interactions in patients requiring the continuous administration of other treatments. CONCLUSION: We must be aware of the pharmacokinetic and pharmacodynamic interactions of AEDs. Because of a lack of significant interactions, drugs such as levetiracetam, gabapentin or pregabalin can be recommended in particular groups such as patients with cancer, transplants, anticoagulant treatments or HIV infection. In all cases, it is important to ensure AED efficacy and prevent serious complications.

Relationship between the efficacy of rivastigmine and apolipoprotein E (epsilon4) in patients with mild to moderately severe Alzheimer disease.

Alzheimer disease is the most common form of dementia in Western countries and the leading cause of disability in the over-65 population. Apolipoprotein E (APOE) is a multifunctional protein implied in lipid metabolism and neurobiology. Polymorphisms of the APOE gene have been associated with a variety of medical disorders, from arteriosclerosis to AD. A high frequency of the APOE epsilon4 allele has been found in patients with AD and they seem to have a higher risk of developing the disease. Various authors have suggested a possible relationship between the efficacy of cholinesterase inhibitors and the presence of the APOE epsilon4 allele. The purpose of the present study was to compare prospectively the efficacy of rivastigmine in patients with mild to moderately severe AD presenting different polymorphisms of the APOE gene on chromosome 19 and to determine if there was a difference in the response to rivastigmine treatment in AD patients with the APOE epsilon4 allele (heterozygous or homozygous) versus patients who had other forms of APOE, such as epsilon2 and epsilon3. This was an open-label, nonrandomized, multicenter study in patients over 50 years of age diagnosed with mild to moderately severe AD. The results of the analysis of this study indicate that the presence of at least one APOE epsilon4 allele does not determine a difference in the response to treatment with rivastigmine. The data indicate that knowledge of the patient's genotype is not necessary for treatment with rivastigmine. It would be interesting in the future to analyze the interaction between these 2 factors using other available anticholinesterase drugs.

Extraction of the intracranial component from the rheoencephalographic signal: a new approach.

The well-known inherent artifact on the rheoencephalogram (REG) caused by the pulsatility of the scalp blood flow left the REG out of the clinical practice. In fact, depending on the selected electrode arrangement, the measurement of the brain impedance changes time-locked with the heartbeat can be completely buried on that of the scalp. In this work, a novel mathematical method based on the physiological differences between the brain and scalp perfusions is proposed to extract the intracranial information from REG. This method is experimentally applied to REG signals recorded at five electrode positions and results are compared with those derived from our previous theoretical works. Intracranial components extracted from the REG signals are consistent with the stated hypothesis and reproduce the unexpected results obtained with our theoretical models. Although further studies would be needed, the evidences found in this work suggest that the method proposed in this work extracts the intracranial information from the REG signal.

Spatiotemporal pattern of the extracranial component of the rheoencephalographic signal.

The use of rheoencephalography (REG) in the clinical practice to evaluate cerebral blood flow is conditional on the finding of a method for removing the extracranial interference caused by the scalp blood flow. To remove this undesirable influence, digital processing based on statistics could be an effective technique if the appropriate data model were applied. This paper focuses on the analysis of the spatiotemporal features of the extracranial REG component, by comparing its morphology and phase shift at several scalp sites. For this purpose, a numerical model of the scalp was employed to assess tissue impedance changes caused by the inflow of a stepwise blood pulse wave. These results were compared with the experimental impedance waveforms recorded on six pairs of adjacent electrodes. The correlation coefficients between each pair of impedance recordings of each subject were always greater than 0.942, showing a mean value of 0.986. This result suggests that the extracranial REG component can be considered as morphologically invariant. On the other hand, negligible phase shifts were observed when mean electrode distances, measured in the blood flow direction, were relatively small, although temporal corrections in the data model would be advisable for longer distances.