Marc C. T. F. M. de Krom

Systematic Review and Meta‐analysis of Incidence Studies of Epilepsy and Unprovoked Seizures

Summary:  Purpose: To evaluate the methodology of incidence studies of epilepsy and unprovoked seizures and to assess the value of their findings by summarizing their results.

Conservative treatment options for carpal tunnel syndrome: a systematic review of randomised controlled trials

Abstract Carpal tunnel syndrome (CTS) is a common disorder, for which various conservative treatment options are available. The objective of this study is to determine the efficacy of the various conservative treatment options for relieving the symptoms of CTS. Computer-aided searches of MEDLINE (1/1966 to 3/2000), EMBASE (1/1988 to 2/2000) and the Cochrane Controlled Trials Register (2000, issue 1) were conducted, together with reference checking. Included were randomised controlled trials evaluating the efficacy of conservative treatment options in a study population of CTS patients, with a full report published in English, German, French or Dutch. Two reviewers independently selected the studies. Fourteen randomised controlled trials were included in the review. Assessment of methodological quality and data-extraction was independently performed by two reviewers. A rating system, based on the number of studies and their methodological quality and findings, was used to determine the strength of the available evidence for the efficacy of the treatment. Diuretics, pyridoxine, non-steroidal anti-inflammatory drugs, yoga and laser-acupuncture seem to be ineffective in providing short-term symptom relief (varying levels of evidence) and steroid injections seem to be effective (limited evidence). There is conflicting evidence for the efficacy of ultrasound and oral steroids. For providing long-term relief from symptoms there is limited evidence that ultrasound is effective, and that splinting is less effective than surgery. In conclusion, there is still little known about the efficacy of most conservative treatment options for CTS. To establish stronger evidence more high quality trials are needed.

The impact of side effects on long-term retention in three new antiepileptic drugs

OBJECTIVE To determine long-term retention, percentage of patients withdrawing because of adverse events, percentage of patients achieving seizure freedom, safety profile of the new anti-epileptic drugs lamotrigine, levetiracetam and topiramate. METHODS All patients treated with lamotrigine, levetiracetam or topiramate in the Epilepsy Centre were identified. Each drug was analyzed from introduction of the drug in the Netherlands up to a final assessment point 2 years later. RESULTS Data from 1066 patients were included: 336 for lamotrigine, 301 for levetiracetam, 429 for topiramate. Two-year retention rates were 69.2% (lamotrigine), 45.8% (levetiracetam), 38.3% (topiramate); (LTG vs. LEV at p<0.001; LTG vs. TPM at p<0.001; LEV vs. TPM at p=0.005). Seizure freedom rates were lowest for lamotrigine and highest for levetiracetam. Adverse events played a role in drug discontinuation in 154/429 patients (35.9%) on topiramate, 52/336 patients (15.5%) on lamotrigine (p<0.001), 68/301 patients (22.5%) on levetiracetam (p<0.001). Mood and general CNS-effects are common in patients on lamotrigine and levetiracetam, and neurocognitive side effects are most prevalent in patients on topiramate. A positive effect on cognition is frequently noted in patients on lamotrigine. CONCLUSION A drug that is only modestly efficacious but has a favourable safety profile may look better than a drug that is more efficacious but produces clinically meaningful adverse events. Therefore, a drugs retention rate is mainly determined by its side effect profile. As a consequence, retention rate was highest for lamotrigine and lowest for topiramate. Intermediate retention rates were seen with levetiracetam use.

Functional MRI reveals declined prefrontal cortex activation in patients with epilepsy on topiramate therapy

Functional magnetic resonance imaging of covert word generation was used to examine brain activation abnormalities associated with topiramate-induced cognitive language impairment in patients with epilepsy. Compared with a control epilepsy group, in the topiramate-treated group, there was significantly less activation in the language-mediating regions of the prefrontal cortex; the topiramate group also had significantly lower neuropsychological language scores. These findings suggest that topiramate has a critical effect on the cerebral neural systems that mediate expressive language.

Consistency of history taking and physical examination in patients with suspected lumbar nerve root involvement

Study Design. A cross-sectional study of interobserver variability in primary care patients. Objective. To investigate the consistency of signs and symptoms of nerve root compression in primary care patients with pain irradiating pain into the leg (sciatica). Summary of Background Data. The literature does not report on all the clinical tests for nerve root compression. In previous studies, most patients had low back pain with no irradiation. Often, little information on examination technique, proportion of positive test results, or clinical patient characteristics was provided. Methods. A random selection of 91 patients was investigated by a neurologist-resident couple. Agreement percentages, proportions of positive test results, and kappas were calculated. Results. The kappa of the overall conclusion after the history taking was 0.40, increasing to 0.66 after physical examination. Kappas were good for decreased muscle strength and sensory loss (0.57–0.82), intermediate for reflex changes (0.42–0.53), and poor for the examination of the lumbar spine (0.16–0.33). The straight leg raising, crossed straight leg raising, Bragard’s sign, and Naffziger’s sign were the most consistent nerve root tension signs (> 0.66). Conclusions. Two clinicians disagreed on the presence of nerve root involvement in one of four patients after history taking, and in one of five patients after physical examination. For a more consistent overall diagnosis, the physician probably should put more emphasis on the history of pain on coughing–straining–sneezing, a feeling of coldness in the legs, and urinary incontinence. The investigation of paresis, sensory loss, reflex changes, straight leg raising, and Bragard’s sign provide the most consistent results.

The diagnosis of epileptic and non-epileptic seizures

The aim of this prospective population-based study was to systematically define a cluster of diagnostic items which can assist in the early identification and classification of epileptic and non-epileptic seizures. A cohort of patients aged > or =14 years, suspected with a first epileptic seizure, were included in this study. A team of neurologists evaluated and classified all cases. Diagnostic items for epileptic and non-epileptic seizures were identified using logistic regression analysis. Three hundred and fifty cases entered this study. Distinctive features for epileptic seizures were postictal confusion (OR 0.09), an epileptiform EEG pattern (OR 0.02), and abnormal neuroimaging findings (OR 0.07), whereas for non-epileptic seizures of organic origin there was a history of hypertension (OR 7.5), and provoking factors (OR 13.4) such as exercise and warmth. Diagnostic items for seizures of non-organic origin were a history of febrile seizures (OR 5.8), treatment by a psychologist or psychiatrist (OR 9.1), and presentiment of the seizure (OR 3.7) such as a feeling of choking and palpitations. A separate analysis for the patients who were systematically investigated provided some additional diagnostic items for the different subgroups of patients. For instance, back arching during the seizure for the patients with seizures of non-organic origin and female sex for the patients with non-epileptic seizures of organic origin.

Estimating the Costs of Epilepsy: An International Comparison of Epilepsy Cost Studies

Summary:  Purpose: To compare systematically the national and per capita estimates of the cost of epilepsy in different countries.

Incidence of epilepsy and predictive factors of epileptic and non-epileptic seizures

PURPOSE To estimate the incidence of unprovoked seizures (US) and epilepsy in a general population from the southern part of the Netherlands, in relation to age, sex, etiology and seizure type, and to identify predictive factors of the epileptic and non-epileptic seizures. METHODS All patients aged > or =14 years with a first seizure or who had undiagnosed seizures before the study period were included. Patients were identified from different sources and were independently evaluated and classified by a team of neurologists. A predictive profile for the occurrence of epileptic and non-epileptic seizures was obtained by stepwise logistic regression analysis. RESULTS The overall annual incidence was 55/100,000 and 30/100,000 for US and epilepsy, respectively. The age-specific annual incidence of US and epilepsy increased with age and reached 120/100,000 and 62/100,000 for the > or =65 years of age group, respectively. The incidence of epilepsy and US in males was higher than in females and partial seizures prevailed over generalized seizures (40 versus 9/100,000). In up to 35% of the cases with US or epilepsy, the etiology was mainly cerebrovascular disease and brain tumors. Predictors for epileptic versus non-epileptic seizures of organic origin were an epileptiform EEG pattern (OR=0.06) versus a history of hypertension (OR=2.8) or cardiovascular disease (OR=5.4). Strong predictors for seizures of non-organic origin were female sex (OR=2.2) and head injury (OR=2.4). CONCLUSIONS The incidence of US and epilepsy (overall, and age-, sex-, seizure-specific) was similar to those reported by other developed countries. The predictive factors found in this study may assist in the early diagnosis of seizures.

The Effect of Antiepileptic Drugs on Cognition: Patient Perceived Cognitive Problems of Topiramate versus Levetiracetam in Clinical Practice

Summary:  Introduction: Neurocognitive complaints may interfere with long‐term antiepileptic drug (AED) treatment and are an important issue in clinical practice. Most data about drug‐induced cognitive problems are derived from highly controlled short‐term clinical trials. We analyzed such cognitive complaints for the two most commonly used AEDs in a clinical setting using patient perceived problems as primary outcome measure.

The costs of epilepsy in three different populations of patients with epilepsy.

The purpose of this study was to estimate the costs of care in three different populations of patients with epilepsy (general practices (GP), University Hospital (UH), and Epilepsy Center (EC)), and to analyse the distribution of costs by type of services for each patient group. A cost diary was developed to obtain prospective information on epilepsy-attributable service use over a period of 3 months. Similar information over the previous 3 months was obtained from a cost questionnaire. In addition, a quality of life inventory (QOLIE-31) was used. Standard cost lists were applied for the valuation of the direct cost items. A sensitivity analysis was performed for certain cost items for which no reliable data were available. One hundred and sixteen patients with established epilepsy were included, and the mean costs per patient per month (in Euros) ranged from 52.08 to 357.63. Patients from GP appeared to have lower direct costs, spent less time in seeking or undergoing a treatment, and reported lower seizure frequencies and less severe seizure types than the patients from the other patient groups. Patients from the EC reported the highest productivity changes and unemployment rates and also had the lowest scores on the QOLIE-31. The cost items anti-epileptic drugs, hospital services, unpaid care, and transportation accounted for the majority of the total direct costs.