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Featured researches published by Loes Leenen.


Epilepsy & Behavior | 2004

Topiramate in clinical practice: long-term experience in patients with refractory epilepsy referred to a tertiary epilepsy center

H.P.R. Bootsma; F Coolen; Albert P. Aldenkamp; J.B.A.M. Arends; Leonie Diepman; J.A.R.J. Hulsman; Danielle A.J.E. Lambrechts; Loes Leenen; Marian Majoie; Ad Schellekens; M.C.T.F.M. de Krom

For the treatment of patients with chronic refractory epilepsies, information about the long-term efficacy and safety profile of any new antiepileptic drug is crucial. Topiramate has been proven to be effective in patients with refractory chronic partial epilepsies in short-term controlled clinical trials, but the long-term retention, long-term efficacy, and long-term side-effect profile have not been sufficiently investigated. We analyzed all patients who had been treated with topiramate in the Epilepsy Centre Kempenhaeghe from the introduction of the drug in the spring of 1993 up to a final assessment point in mid-2002. In total, 470 patients were identified. The data show that the clinical dose achieved was about 200mg/day, reached after approximately 6 months of treatment. Further dose escalation in the survivors was slow, with a mean dose of about 300 mg/day after 24 months of treatment. Mean titration dose is 25mg/week, but titration strategy is mostly individual and responds to patient complaints. With respect to seizure frequency, 10-15% of the patients were seizure-free at the 6-month evaluation; 4 patients achieved a 2-year remission. Retention rate was 53% after 1 year, 45% after 2 years, 38% after 3 years, and 30% after 4 years. At 4 years, almost 70% of the patients had discontinued topiramate. The main reason was adverse events, which accounted for about 65% of the discontinuations. Behavioral side effects were dominant, with mental slowing (27.6%), dysphasia (16.0%), and mood problems (agitation: 11.9%) being the most frequently reported side effects. In about 10% of the patients side effects led to discontinuation despite the obvious favorable effects on seizure frequency. Comparisons between the patients who discontinued topiramate treatment and those who continued topiramate showed that discontinuation was associated with comedication (vigabatrin and lamotrigine). Our conclusion is that TPM is associated with a high incidence of side effects in clinical practice, affecting long-term retention. Meaningful prognostic factors that may help us in clinical decision making, i.e., to prevent the side effects or to help us identify those at risk, have not been found.


Developmental Medicine & Child Neurology | 2012

Vagus nerve stimulation in children with intractable epilepsy: a randomized controlled trial

Sylvia Klinkenberg; Marlien W. Aalbers; Johan S.H. Vles; Erwin M. J. Cornips; Kim Rijkers; Loes Leenen; Fons Kessels; Albert P. Aldenkamp; Marian Majoie

Aim  The aim of this study was to evaluate the effects of vagus nerve stimulation (VNS) in children with intractable epilepsy on seizure frequency and severity and in terms of tolerability and safety.


Seizure-european Journal of Epilepsy | 2008

Long-term effects of levetiracetam and topiramate in clinical practice: A head-to-head comparison.

H.P.R. Bootsma; L. Ricker; Leonie Diepman; J. Gehring; J.A.R.J. Hulsman; Danielle A.J.E. Lambrechts; Loes Leenen; Marian Majoie; Ad Schellekens; M.C.T.F.M. De Krom; Albert P. Aldenkamp

OBJECTIVE Two of the most commonly prescribed new antiepileptic drugs as add-on therapy for patients with chronic refractory epilepsies are topiramate and levetiracetam. In regulatory trials, both drugs were characterized as very promising new antiepileptic drugs. However, results from these highly controlled short-term clinical trials cannot simply be extrapolated to everyday clinical practice, also because head-to-head comparisons are lacking. Therefore, results from long-term open label observational studies that compare two or more new AEDs are crucial to determine the long-term performance of competing new antiepileptic drugs in clinical practice. METHOD We analyzed all patients referred to a tertiary epilepsy centre who had been treated with topiramate from the introduction of the drug in spring 1993 up to a final assessment point mid-2002 and all patients who had been treated with LEV in the same centre from the introduction of the drug in early 2001 up to a final assessment point end-2003 using a medical information system. RESULTS Three hundred and one patients were included for levetiracetam and 429 patients for TPM. Retention rate after 1 year was 65.6% for LEV-treated patients and 51.7% for TPM-treated patients (p=0.0015). Similarly, retention rates for LEV were higher at the 24-month mark: 45.8% of LEV-treated patients and 38.3% of TPM-treated patients were still continuing treatment (p=0.0046). Adverse events led to drug discontinuation in 21.9% of TPM-treated patients compared to 6.0% of LEV-treated patients (p<0.001). The number of patients discontinuing treatment because of lack of efficacy was similar for both groups. Seizure freedom rates varied between 11.6 and 20.0% for TPM and between 11.1 and 14.3% for LEV per 6-months interval. Several important AED specific adverse events leading to drug discontinuation were identified, including neurocognitive side effects from TPM and mood disorders from LEV. CONCLUSION The retention rate for LEV is significantly higher than for TPM. LEV had a more favourable side effect profile than TPM with comparable efficacy. Patients on TPM discontinued treatment mainly because of neurocognitive side effects. In the treatment with LEV, the effects on mood must not be underestimated.


Epilepsia | 2006

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

Hans-Peter R. Bootsma; Albert P. Aldenkamp; Leonie Diepman; J.A.R.J. Hulsman; Danielle A.J.E. Lambrechts; Loes Leenen; Marian Majoie; Ad Schellekens; Marc C. T. F. M. de Krom

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.


PLOS ONE | 2013

Vagus nerve stimulation increases energy expenditure: relation to brown adipose tissue activity

Guy H. E. J. Vijgen; Nicole D. Bouvy; Loes Leenen; Kim Rijkers; Erwin M. J. Cornips; Marian Majoie; Boudewijn Brans; Wouter D. van Marken Lichtenbelt

Background Human brown adipose tissue (BAT) activity is inversely related to obesity and positively related to energy expenditure. BAT is highly innervated and it is suggested the vagus nerve mediates peripheral signals to the central nervous system, there connecting to sympathetic nerves that innervate BAT. Vagus nerve stimulation (VNS) is used for refractory epilepsy, but is also reported to generate weight loss. We hypothesize VNS increases energy expenditure by activating BAT. Methods and Findings Fifteen patients with stable VNS therapy (age: 45±10yrs; body mass index; 25.2±3.5 kg/m2) were included between January 2011 and June 2012. Ten subjects were measured twice, once with active and once with inactivated VNS. Five other subjects were measured twice, once with active VNS at room temperature and once with active VNS under cold exposure in order to determine maximal cold-induced BAT activity. BAT activity was assessed by 18-Fluoro-Deoxy-Glucose-Positron-Emission-Tomography-and-Computed-Tomography. Basal metabolic rate (BMR) was significantly higher when VNS was turned on (mean change; +2.2%). Mean BAT activity was not significantly different between active VNS and inactive VNS (BAT SUVMean; 0.55±0.25 versus 0.67±0.46, P = 0.619). However, the change in energy expenditure upon VNS intervention (On-Off) was significantly correlated to the change in BAT activity (r = 0.935, P<0.001). Conclusions VNS significantly increases energy expenditure. The observed change in energy expenditure was significantly related to the change in BAT activity. This suggests a role for BAT in the VNS increase in energy expenditure. Chronic VNS may have a beneficial effect on the human energy balance that has potential application for weight management therapy. Trial Registration The study was registered in the Clinical Trial Register under the ClinicalTrials.gov Identifier NCT01491282.


European Journal of Paediatric Neurology | 2013

Behavioural and cognitive effects during vagus nerve stimulation in children with intractable epilepsy – A randomized controlled trial

Sylvia Klinkenberg; Charlotte N.C.J. van den Bosch; H. J. Marian Majoie; Marlien W. Aalbers; Loes Leenen; Jos G.M. Hendriksen; Erwin M. J. Cornips; Kim Rijkers; Johan S.H. Vles; Albert P. Aldenkamp

BACKGROUND/AIMS In addition to effects on seizure frequency in intractable epilepsy, multiple studies report benefits of vagus nerve stimulation (VNS) on behavioural outcomes and quality of life. The present study aims to investigate the effects of VNS on cognition, mood in general, depression, epilepsy-related restrictions and psychosocial adjustment in children with intractable epilepsy, as well as the relation between these effects and seizure reduction. METHODS We conducted a randomized, active-controlled, double-blinded, add-on study in 41 children (age 4-18) with medically refractory epilepsy. We performed cognitive and behavioural testing at baseline (12 weeks), at the end of the blinded phase (20 weeks) in children receiving either high-output or low-output (active control) stimulation, and at the end of the open label phase (19 weeks) with all children receiving high-output stimulation. Seizure frequency was recorded using seizure diaries. RESULTS VNS did not have a negative effect on cognition nor on psychosocial adjustment. At the end of the follow-up phase we noted an improvement of mood in general and the depression subscale for the entire group, unrelated to a reduction of seizure frequency. At the end of the blinded phase a ≥50% reduction of seizure frequency occurred in 16% of the high-stimulation group and 21% of the low-stimulation group. At the end of the open-label follow-up phase, 26% of the children experienced a seizure frequency reduction of 50% or more (responders). CONCLUSIONS VNS has additional beneficial effects in children with intractable epilepsy. As opposed to anti-epileptic drugs, there are no negative effects on cognition. Moreover, we observed an improvement of mood in general and depressed feelings in particular, irrespective of a reduction in seizure frequency. These beneficial effects should be taken into account when deciding whether to initiate or continue VNS treatment in these children.


Epilepsy & Behavior | 2005

Ketter’s hypothesis of the mood effects of antiepileptic drugs coupled to the mechanism of action of topiramate and levetiracetam

Gloria Roberts; H.J.M. Majoie; Loes Leenen; H.P. Bootsma; Alfons G. H. Kessels; Albert P. Aldenkamp; B.E. Leonard

Mood-modulating profiles of antiepileptic drugs (AEDs) have been classified by Ketter, Post, and Theodore [Neurology 1999; 53 (5, Suppl. 2) S53-76] into two classes: the first class is assumed to have deactivating effects related to GABA potentiation, and the second class is assumed to have activating effects that are associated with glutamate attenuation. We tested this hypothesis by reviewing the multiple mechanisms of action of topiramate (TPM) and levetiracetam (LEV) together with clinical behavioral side effects of patients who had been treated with TPM and LEV in a tertiary referral center for epilepsy. We found LEV to manifest activating and deactivating side effects equally and TPM to act as a deactivating AED, with tiredness/sleepiness side effects being predominant. TPM, in comparison to LEV, was found to be associated with a high incidence of side effects. Testing the hypothesis of Ketter et al. (1999) the deactivating effects of TPM may be coupled to a predominance of potentiation of GABA, but the oversimplified basis of the model needs to be acknowledged.


BMC Neurology | 2014

(Cost)-effectiveness of a multi-component intervention for adults with epilepsy: study protocol of a Dutch randomized controlled trial (ZMILE study)

Loes Leenen; Ben F.M. Wijnen; Reina J.A. de Kinderen; Marian Majoie; Caroline M. van Heugten; Silvia M. A. A. Evers

BackgroundIn patients with epilepsy, poor adherence to anti-epileptic drugs has been shown to be the most important cause of poorly controlled epilepsy. Furthermore, it has been noted that the quality of life among patients with epilepsy can be improved by counseling and treatments aimed at increasing their self-efficacy and concordance, thus stimulating self-management skills. However, there is a need for evidence on the effectiveness of such programs, especially within epilepsy care. Therefore, we have developed a multi-component intervention (MCI) which combines a self-management/education program with e-Health interventions. Accordingly, the overall objective of this study is to assess the (cost)-effectiveness and feasibility of the MCI, aiming to improve self-efficacy and concordance in patients with epilepsy.MethodsA RCT in two parallel groups will be conducted to compare the MCI with a control condition in epilepsy patients. One hundred eligible epilepsy patients will be recruited and allocated to either the intervention or control group. The intervention group will receive the MCI consisting of a self-management/education program of six meetings, including e-Health interventions, and will be followed for 12 months. The control group will receive care as usual and will be followed for 6 months, after which patients will be offered the possibility of participating in the MCI. The study will consist of three parts: 1) a clinical effectiveness study, 2) a cost-effectiveness study, and 3) process evaluation. The primary outcome will be self-efficacy. Secondary outcomes include adherence, side effects, change in seizure severity & frequency, improved quality of life, proactive coping, and societal costs. Outcome assessments will be done using questionnaires at baseline and after 3, 6, 9, and 12 months (last two applicable only for intervention group).DiscussionIn times of budget constraints, MCI could be a valuable addition to the current healthcare provision for epilepsy, as it is expected that higher concordance and self-efficacy will result in reduced use of healthcare resources and an increased QOL. Accordingly, this study is aimed helping patients to be their own provider of health care, shifting epilepsy management from professionals to self-care by patients equipped with appropriate skills and tools.Trial registration numberNTR4484.


Epilepsy & Behavior | 2016

Are people with epilepsy using eHealth-tools?

Loes Leenen; Ben F.M. Wijnen; Reina J.A. de Kinderen; Caroline M. van Heugten; Silvia M. A. A. Evers; Marian Majoie

INTRODUCTION Self-management for people with epilepsy (PWE) should lead to shared decision-making and thus to adherence to the treatment plan. eHealth is an important way of supporting PWE in their self-management. METHOD In this survey, we used a mixed method to explore the following: 1) which factors were monitored by PWE and how (using pen and paper or eHealth-tools), 2) how many PWE own a computer or smartphone, and 3) how do they perceive the use of eHealth. A consecutive series of 1000 PWE attending the outpatient clinic of a tertiary epilepsy center were asked to fill in a questionnaire. RESULTS In comparison with the general population, fewer PWE owned a computer or smartphone. They were, however, more likely to self-monitor their health than other patients suffering from a chronic condition. Although PWE did not use eHealth-tools often, they perceived it as a user-friendly tool, promoting health behavior as well as adherence. On the other hand, problems with privacy and the perception that not everyone is able to use eHealth were considered as disadvantages by PWE. Promoting self-care was perceived as both an advantage and a disadvantage. It was seen as an advantage when PWE mentioned the option of eHealth-tools in order to gain insight into ones epilepsy. At the same time, it was seen as a disadvantage because it confronts PWE with their disease, which causes emotional stress. CONCLUSION The high level of self-monitoring combined with a low usage of eHealth-tools seems to indicate that there is a need for a more tailored approach to stimulate the use of eHealth-tools by PWE. Further research should focus on this aspect, e.g., what PWE need in order to make more use of eHealth-tools in their self-care.


Epilepsy & Behavior | 2017

Process evaluation of a multi-component self-management intervention for adults with epilepsy (ZMILE study)

Loes Leenen; Ben F.M. Wijnen; Jolanda C. M. van Haastregt; Reina J.A. de Kinderen; Silvia M. A. A. Evers; Marian Majoie; Caroline M. van Heugten

BACKGROUND People with epilepsy need to monitor and manage their symptoms. They, as well as their relatives, have to deal with the psychological burden, reflected in a reduced quality of life. Support in self-management can be of importance. We have developed a multi-component self-management intervention for patients and their relatives (MCI). This eight-week group intervention is conducted by nurse practitioners and consists of six two-hour sessions. The main components are: 1) providing self-management education, 2) stimulating proactive coping and goal-setting and 3) facilitating peer and social support. This study is a process evaluation to establish the feasibility, fidelity and acceptability of the intervention by assessing performance according to protocol, attendance and adherence, and the opinion of patients, relatives and facilitators about the intervention. METHOD Study population consists of 52 patients with epilepsy living in the community (e.g. at home), 37 relatives and six facilitators. In this prospective mixed methods study, data were gathered using questionnaires for patients and relatives, registration forms for facilitators and by carrying out semi-structured group interviews with patients, relatives and facilitators. RESULTS Patients and relatives attended a mean of 5.2 sessions. Forty-seven (90%) patients and 32 (86.5%) relatives attended at least five sessions. The mean group size was 8.1 (SD=1.3; range 6-10). All elements of the intervention were offered to participants, except for one e-Health tool which was only available at the start of the study. Overall, the sessions were considered useful by patients, their relatives and facilitators. The participation of a relative (social support) and sharing ideas and feelings about having epilepsy with peers (peer support) were rated as important aspects. CONCLUSION This process evaluation revealed that the MCI was largely performed according to protocol, attendance rate was high, and participants and facilitators had, on the whole, a favourable opinion about the MCI, and would recommend it to others with epilepsy and their relatives. Overall, the adherence of patients and relatives was high. The MCI is considered feasible according to patients, relatives and facilitators. Implementation is recommended if the intervention proves to be effective.

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Silvia M. A. A. Evers

Public Health Research Institute

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