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Perry J, McLeod MC, Reed RD, Baker GA, Stanford LA, Allen J, Jones B, Robinson T, MacLennan PA, Kumar V, Locke JE. Patient-Level and Center-Level Factors Associated with Required Predonation Weight Loss among Obese Living Kidney Donors. KIDNEY360 2024; 5:437-444. [PMID: 38319632 PMCID: PMC11000741 DOI: 10.34067/kid.0000000000000381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 01/29/2024] [Indexed: 02/07/2024]
Abstract
Key Points Among obese living kidney donors, year of donation, preoperative body mass index, hypertension, and center percent of living kidney donor transplants were associated with required predonation weight loss. There were no significant differences in the likelihood of predonation weight loss requirement by race, sex, or age or by markers of preoperative metabolic dysfunction. Background The proportion of overweight/mildly obese living kidney donors (OLKDs) has increased in the past few decades, with significant center variation in the body mass index (BMI) of LKDs. The purpose of this study was to examine factors associated with required predonation weight loss among OLKDs (BMI, ≥30 kg/m2). Methods This retrospective cohort study surveyed 1097 OLKDs (1979–2020) (mean BMI, 33 kg/m2) about their donation experience. Bivariate analyses compared donor demographic and center characteristics by whether the donor reported predonation weight loss requirement. Generalized estimating equations with logit link were used to estimate marginal effects of patient-level and center-level factors. Multiple imputation using chained equations was implemented to account for missing values. Results Of 1097 OLKDs surveyed, 340 (31.0%) reported predonation weight loss requirement. Donors with a predonation weight loss requirement had slightly higher predonation BMIs and donated in more recent years at centers performing a lower percentage of living donor nephrectomies and with a lower median BMI. In multivariable logistic regression analysis, we observed transplant year (odds ratio [OR], 1.04 per year donation; 95% confidence interval [CI], 1.01 to 1.07; P = 0.005), preoperative BMI (OR, 1.16; 95% CI, 1.05 to 1.28; P < 0.01), preoperative hypertension (OR, 1.61; 95% CI, 1.08 to 2.40; P = 0.02), and center percentage of living donor kidney transplants (OR, 0.99; 95% CI, 0.98 to 1.00; P = 0.02) as significantly associated with a predonation weight loss requirement. The study found no differences in the likelihood of predonation weight loss requirement by race, sex, age, preoperative creatinine, preoperative metabolic dysfunction, or center-level median BMI of living donors. Conclusions These results suggest that both center-level and patient-level factors influence whether OLKDs are required to lose weight before donation. Future study is needed to determine whether predonation weight loss is associated with improved long-term postdonation outcomes.
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Jones-Carr ME, Fatima H, Kumar V, Anderson DJ, Houp J, Perry JC, Baker GA, McManus L, Shunk AJ, Porrett PM, Locke JE. C5 inhibition with eculizumab prevents thrombotic microangiopathy in a case series of pig-to-human kidney xenotransplantation. J Clin Invest 2024; 134:e175996. [PMID: 38269581 PMCID: PMC10904036 DOI: 10.1172/jci175996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024] Open
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Reed RD, McLeod MC, MacLennan PA, Kumar V, Pittman SE, Maynor AG, Stanford LA, Baker GA, Schinstock CA, Silkensen JR, Roll GR, Segev DL, Orandi BJ, Lewis CE, Locke JE. Change in Body Mass Index and Attributable Risk of New-Onset Hypertension Among Obese Living Kidney Donors. Ann Surg 2023; 278:e115-e122. [PMID: 35946818 PMCID: PMC9911559 DOI: 10.1097/sla.0000000000005669] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To examine whether body mass index (BMI) changes modify the association between kidney donation and incident hypertension. BACKGROUND Obesity increases hypertension risk in both general and living kidney donor (LKD) populations. Donation-attributable risk in the context of obesity, and whether weight change modifies that risk, is unknown. METHODS Nested case-control study among 1558 adult LKDs (1976-2020) with obesity (median follow-up: 3.6 years; interquartile range: 2.0-9.4) and 3783 adults with obesity in the Coronary Artery Risk Development in Young Adults (CARDIA) and Atherosclerosis Risk in Communities (ARIC) studies (9.2 y; interquartile range: 5.3-15.8). Hypertension incidence was compared by donor status using conditional logistic regression, with BMI change investigated for effect modification. RESULTS Overall, LKDs and nondonors had similar hypertension incidence [incidence rate ratio (IRR): 1.16, 95% confidence interval (95% CI): 0.94-1.43, P =0.16], even after adjusting for BMI change (IRR: 1.25, 95% CI: 0.99-1.58, P =0.05). Although LKDs and nondonors who lost >5% BMI had comparable hypertension incidence (IRR: 0.78, 95% CI: 0.46-1.34, P =0.36), there was a significant interaction between donor and >5% BMI gain (multiplicative interaction IRR: 1.62, 95% CI: 1.15-2.29, P =0.006; relative excess risk due to interaction: 0.90, 95% CI: 0.24-1.56, P =0.007), such that LKDs who gained weight had higher hypertension incidence than similar nondonors (IRR: 1.83, 95% CI: 1.32-2.53, P <0.001). CONCLUSIONS Overall, LKDs and nondonors with obesity had similar hypertension incidence. Weight stability and loss were associated with similar hypertension incidence by donor status. However, LKDs who gained >5% saw increased hypertension incidence versus similar nondonors, providing support for counseling potential LKDs with obesity on weight management postdonation.
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Killian AC, Reed RD, McLeod MC, MacLennan PA, Kumar V, Pittman SE, Maynor AG, Stanford LA, Baker GA, Schinstock CA, Silkensen JR, Roll GR, Segev DL, Orandi BJ, Lewis CE, Locke JE. Diabetes-free survival among living kidney donors and non-donors with obesity: A longitudinal cohort study. PLoS One 2022; 17:e0276882. [PMID: 36399462 PMCID: PMC9674148 DOI: 10.1371/journal.pone.0276882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 10/13/2022] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Approval of living kidney donors (LKD) with end-stage kidney disease (ESKD) risk factors, such as obesity, has increased. While lifetime ESKD development data are lacking, the study of intermediate outcomes such as diabetes is critical for LKD safety. Donation-attributable diabetes risk among persons with obesity remains unknown. The purpose of this study was to evaluate 10-year diabetes-free survival among LKDs and non-donors with obesity. METHODS This longitudinal cohort study identified adult, LKDs (1976-2020) from 42 US transplant centers and non-donors from the Coronary Artery Risk Development in Young Adults (1985-1986) and the Atherosclerosis Risk in Communities (1987-1989) studies with body mass index ≥30 kg/m2. LKDs were matched to non-donors on baseline characteristics (age, sex, race, body mass index, systolic and diastolic blood pressure) plus diabetes-specific risk factors (family history of diabetes, impaired fasting glucose, smoking history). Accelerated failure time models were utilized to evaluate 10-year diabetes-free survival. FINDINGS Among 3464 participants, 1119 (32%) were LKDs and 2345 (68%) were non-donors. After matching on baseline characteristics plus diabetes-specific risk factors, 4% (7/165) LKDs and 9% (15/165) non-donors developed diabetes (median follow-up time 8.5 (IQR: 5.6-10.0) and 9.1 (IQR: 5.9-10.0) years, respectively). While not significant, LKDs were estimated to live diabetes-free 2 times longer than non-donors (estimate 1.91; 95% CI: 0.79-4.64, p = 0.15). CONCLUSIONS LKDs with obesity trended toward living longer diabetes-free than non-donors with obesity, suggesting within the decade following donation there was no increased diabetes risk among LKDs. Further work is needed to evaluate donation-attributable diabetes risk long-term.
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Baxendale SA, Wilson SJ, Baker GA, Barr W, Helmstaedter C, Hermann BP, Langfitt J, Reuner G, Rzezak P, Samson S, Smith ML. Ten things every neurologist needs to know about neuropsychological assessments and interventions in people with epilepsy. Eur J Neurol 2019; 27:215-220. [PMID: 31610070 DOI: 10.1111/ene.14104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 08/05/2019] [Indexed: 11/30/2022]
Abstract
This paper describes 10 core features of a neuropsychological assessment with the aim of helping neurologists understand the unique contribution the evaluation can make within the wider context of diagnostic methods in epilepsy. The possibilities, limitations and cautions associated with the investigation are discussed under the following headings. (1) A neuropsychological assessment is a collaborative investigation. (2) Assessment prior to treatment allows for the accurate assessment of treatment effects. (3) The nature of an underlying lesion and its neurodevelopmental context play an important role in shaping the associated neuropsychological deficit. (4) Cognitive and behavioural impairments result from the essential comorbidities of epilepsy which can be considered as much a disorder of cognition and behaviour as of seizures. (5) Patients' subjective complaints can help us understand objective cognitive impairments and their underlying neuroanatomy, resulting in improved patient care. At other times, patient complaints reflect other factors and require careful interpretation. (6) The results from a neuropsychological assessment can be used to maximize the educational and occupational potentials of people with epilepsy. (7) Not all patients are able to engage with a neuropsychological assessment. (8) There are limitations in assessments conducted in a second language with tests that have been standardized on different populations from that of the patient. (9) Adequate intervals between assessments maximize sensitivity to meaningful change. (10) Patients should be fully informed about the purpose of the assessment and have realistic expectations of the outcome prior to referral.
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Faraone A, Wagle DV, Baker GA, Novak EC, Ohl M, Reuter D, Lunkenheimer P, Loidl A, Mamontov E. Glycerol Hydrogen-Bonding Network Dominates Structure and Collective Dynamics in a Deep Eutectic Solvent. J Phys Chem B 2018; 122:1261-1267. [PMID: 29336157 DOI: 10.1021/acs.jpcb.7b11224] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The deep eutectic solvent glyceline formed by choline chloride and glycerol in 1:2 molar ratio is much less viscous compared to glycerol, which facilitates its use in many applications where high viscosity is undesirable. Despite the large difference in viscosity, we have found that the structural network of glyceline is completely defined by its glycerol constituent, which exhibits complex microscopic dynamic behavior, as expected from a highly correlated hydrogen-bonding network. Choline ions occupy interstitial voids in the glycerol network and show little structural or dynamic correlations with glycerol molecules. Despite the known higher long-range diffusivity of the smaller glycerol species in glyceline, in applications where localized dynamics is essential (e.g., in microporous media), the local transport and dynamic properties must be dominated by the relatively loosely bound choline ions.
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Charlton RA, McGrogan A, Snowball J, Yates LM, Wood A, Clayton-Smith J, Smithson WH, Richardson JL, McHugh N, Thomas SHL, Baker GA, Bromley R. Sensitivity of the UK Clinical Practice Research Datalink to Detect Neurodevelopmental Effects of Medicine Exposure in Utero: Comparative Analysis of an Antiepileptic Drug-Exposed Cohort. Drug Saf 2017; 40:387-397. [PMID: 28188601 PMCID: PMC5384950 DOI: 10.1007/s40264-017-0506-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Introduction Electronic healthcare data have several advantages over prospective observational studies, but the sensitivity of data on neurodevelopmental outcomes and its comparability with data generated through other methodologies is unknown. Objectives The objectives of this study were to determine whether data from the UK Clinical Practice Research Datalink (CPRD) produces similar risk estimates to a prospective cohort study in relation to the risk of neurodevelopmental disorders (NDDs) following prenatal antiepileptic drug (AED) exposure. Methods A cohort of mother–child pairs of women with epilepsy (WWE) was identified in the CPRD and matched to a cohort without epilepsy. The study period ran from 1 January 2000 to 31 March 2007 and children were required to be in the CPRD at age 6 years. AED exposure during pregnancy was determined from prescription data and children with an NDD diagnosis by 6 years were identified from Read clinical codes. The prevalence and risk of NDDs was calculated for mother–child pairs in WWE stratified by AED regimen and for those without epilepsy. Comparisons were made with the results of the prospective Liverpool and Manchester Neurodevelopment Group study which completed assessment on 201 WWE and 214 without epilepsy at age 6 years. Results In the CPRD, 1018 mother–child pairs to WWE and 6048 to women without epilepsy were identified. The CPRD identified a lower prevalence of NDDs than the prospective study. In both studies, NDDs were more frequently reported in children of WWE than women without epilepsy, although the CPRD risk estimate was lower (2.16 vs. 0.96%, p < 0.001 and 7.46 vs. 1.87%, p = 0.0128). NDD prevalence differed across AED regimens but the CPRD data did not replicate the significantly higher risk of NDDs following in utero monotherapy valproate exposure (adjusted odds ratio [ORadj] 2.02, 95% confidence interval [CI] 0.52–7.86) observed in the prospective study (ORadj 6.05, 95% CI 1.65–24.53). Conclusion It was possible to identify NDDs in the CPRD; however, the CPRD appears to under-record these outcomes. Larger studies are required to investigate further. Electronic supplementary material The online version of this article (doi:10.1007/s40264-017-0506-5) contains supplementary material, which is available to authorized users.
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Pohlmann-Eden B, Aldenkamp A, Baker GA, Brandt C, Cendes F, Coras R, Crocker CE, Helmstaedter C, Jones-Gotman M, Kanner AM, Mazarati A, Mula M, Smith ML, Omisade A, Tellez-Zenteno J, Hermann BP. The relevance of neuropsychiatric symptoms and cognitive problems in new-onset epilepsy - Current knowledge and understanding. Epilepsy Behav 2015; 51:199-209. [PMID: 26291774 DOI: 10.1016/j.yebeh.2015.07.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 07/03/2015] [Indexed: 01/11/2023]
Abstract
Neurobehavioral and cognition problems are highly prevalent in epilepsy, but most research studies to date have not adequately addressed the precise nature of the relationship between these comorbidities and seizures. To address this complex issue and to facilitate collaborative, innovative research in the rising field of neurobehavioral comorbidities and cognition disturbances in new-onset epilepsy, international epilepsy experts met at the 3rd Halifax International Epilepsy Conference & Retreat at White Point, South Shore, Nova Scotia, Canada from September 18 to 20, 2014. This Conference Proceedings provides a summary of the conference proceedings. Specifically, the following topics are discussed: (i) role of comorbidities in epilepsy diagnosis and management, (ii) role of antiepileptic medications in understanding the relationship between epilepsy and neurobehavioral and cognition problems, and (iii) animal data and diagnostic approaches. Evidence to date, though limited, strongly suggests a bidirectional relationship between epilepsy and cognitive and psychiatric comorbidities. In fact, it is likely that seizures and neurobehavioral problems represent different symptoms of a common etiology or network-wide disturbance. As a reflection of this shared network, psychiatric comorbidities and/or cognition problems may actually precede the seizure occurrence and likely get often missed if not screened.
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Helmstaedter C, Aldenkamp AP, Baker GA, Mazarati A, Ryvlin P, Sankar R. Disentangling the relationship between epilepsy and its behavioral comorbidities - the need for prospective studies in new-onset epilepsies. Epilepsy Behav 2014; 31:43-7. [PMID: 24333577 DOI: 10.1016/j.yebeh.2013.11.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Revised: 11/04/2013] [Accepted: 11/09/2013] [Indexed: 12/20/2022]
Abstract
It has been long recognized that there is more to epilepsy than seizures. The prevalence of such neurobehavioral abnormalities as cognitive and mood disorders, autism spectrum disorder, and attention deficit and hyperactivity disorder (ADHD) is significantly higher among patients with epilepsy than in the general population. A long-held view that comorbidities of epilepsy represent mere epiphenomena of seizures has undergone substantial transformation during the past decade, as emerging clinical evidence and experimental evidence suggest the involvement of specific neurobiological mechanisms in the evolution of neurobehavioral deficits in patients with epilepsy. Developmental aspects of both epilepsy and its comorbidities, as well as the frequently reported reciprocal connection between these disorders, both add other dimensions to the already complex problem. In light of progress in effective seizure management in many patients with epilepsy, the importance of neurobehavioral comorbidities has become acute, as the latter are frequently more detrimental to patients' quality of life compared with seizures. This calls for a serious increase in efforts to effectively predict, manage, and ideally cure these comorbidities. Coordinated multicenter clinical, translational, and basic research studies focusing on epidemiology, neuropsychology, neurophysiology, imaging, genetics, epigenetics, and pharmacology of neurobehavioral comorbidities of epilepsy are absolutely instrumental for ensuring tangible progress in the field. Clinical research should focus more on new-onset epilepsy and put particular emphasis on longitudinal studies in large cohorts of patients and groups at risk, while translational research should primarily focus on the development of valid preclinical systems which would allow investigating the fundamental mechanism of epilepsy comorbidities. The final goal of the described research efforts would lie in producing an armamentarium of evidence-based diagnostic tools and therapeutic interventions which would at minimum mitigate and at maximum prevent or abolish neurobehavioral comorbidities of epilepsy and, thus, improve the quality of life of those patients with epilepsy who suffer from the said comorbidities.
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Meador KJ, Baker GA, Browning N, Cohen MJ, Bromley RL, Clayton-Smith J, Kalayjian LA, Kanner A, Liporace JD, Pennell PB, Privitera M, Loring DW. Effects of fetal antiepileptic drug exposure: outcomes at age 4.5 years. Neurology 2012; 78:1207-14. [PMID: 22491865 DOI: 10.1212/wnl.0b013e318250d824] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To examine outcomes at age 4.5 years and compare to earlier ages in children with fetal antiepileptic drug (AED) exposure. METHODS The NEAD Study is an ongoing prospective observational multicenter study, which enrolled pregnant women with epilepsy on AED monotherapy (1999-2004) to determine if differential long-term neurodevelopmental effects exist across 4 commonly used AEDs (carbamazepine, lamotrigine, phenytoin, or valproate). The primary outcome is IQ at 6 years of age. Planned analyses were conducted using Bayley Scales of Infant Development (BSID at age 2) and Differential Ability Scale (IQ at ages 3 and 4.5). RESULTS Multivariate intent-to-treat (n = 310) and completer (n = 209) analyses of age 4.5 IQ revealed significant effects for AED group. IQ for children exposed to valproate was lower than each other AED. Adjusted means (95% confidence intervals) were carbamazepine 106 (102-109), lamotrigine 106 (102-109), phenytoin 105 (102-109), valproate 96 (91-100). IQ was negatively associated with valproate dose, but not other AEDs. Maternal IQ correlated with child IQ for children exposed to the other AEDs, but not valproate. Age 4.5 IQ correlated with age 2 BSID and age 3 IQ. Frequency of marked intellectual impairment diminished with age except for valproate (10% with IQ <70 at 4.5 years). Verbal abilities were impaired for all 4 AED groups compared to nonverbal skills. CONCLUSIONS Adverse cognitive effects of fetal valproate exposure persist to 4.5 years and are related to performances at earlier ages. Verbal abilities may be impaired by commonly used AEDs. Additional research is needed.
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Shallcross R, Bromley RL, Irwin B, Bonnett LJ, Morrow J, Baker GA. Child development following in utero exposure: levetiracetam vs sodium valproate. Neurology 2011; 76:383-9. [PMID: 21263139 DOI: 10.1212/wnl.0b013e3182088297] [Citation(s) in RCA: 97] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE Children born to women with epilepsy (WWE), exposed in utero to levetiracetam (LEV, n = 51), were assessed for early cognitive development and compared to children exposed to sodium valproate in utero (VPA, n = 44) and a group of children representative of the general population (n = 97). METHODS Children were recruited prospectively from 2 cohorts in the United Kingdom and assessed using the Griffiths Mental Development Scale (1996), aged <24 months. Information regarding maternal demographics were collected and controlled for. This is an observational study with researchers not involved in the clinical management of the WWE. RESULTS On overall developmental ability, children exposed to LEV obtained higher developmental scores when compared to children exposed to VPA (p < 0.001). When compared, children exposed to LEV did not differ from control children (p = 0.62) on overall development. Eight percent of children exposed to LEV in utero fell within the below average range (DQ score of <84), compared with 40% of children exposed to VPA. After controlling for maternal epilepsy and demographic factors using linear regression analysis, exposure to LEV in utero was not associated with outcome (p = 0.67). Conversely, when compared with VPA exposure, LEV exposure was associated with higher scores for the overall developmental quotient (p < 0.001). CONCLUSION Children exposed to LEV in utero are not at an increased risk of delayed early cognitive development under the age of 24 months. LEV may therefore be a preferable drug choice, where appropriate, for WWE prior to and of childbearing age.
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Perucca P, Jacoby A, Marson AG, Baker GA, Lane S, Benn EKT, Thurman DJ, Hauser WA, Gilliam FG, Hesdorffer DC. Adverse antiepileptic drug effects in new-onset seizures: a case-control study. Neurology 2011; 76:273-9. [PMID: 21242496 DOI: 10.1212/wnl.0b013e318207b073] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
OBJECTIVE Adverse effects (AEs) are a major concern when starting antiepileptic drug (AED) treatment. This study quantified the extent to which AE reporting in people with new-onset seizures started on AEDs is attributable to the medication per se, and investigated variables contributing to AE reporting. METHODS We pooled data from 2 large prospective studies, the Multicenter Study of Early Epilepsy and Single Seizures and the Northern Manhattan Study of incident unprovoked seizures, and compared adverse event profile (AEP) total and factor scores between adult cases prescribed AEDs for new-onset seizures and untreated controls, adjusting for several demographic and clinical variables. Differences in AEP scores were also tested across different AED monotherapies and controls, and between cases and controls grouped by number of seizures. RESULTS A total of 212 cases and 206 controls were identified. Most cases (94.2%) were taking low AED doses. AEP scores did not differ significantly between the 2 groups. Depression, female gender, symptomatic etiology, younger seizure onset age, ≥2 seizures, and history of febrile seizures were associated with higher AEP scores. There were no significant differences in AEP scores across different monotherapies and controls. AEP scores increased in both cases and controls with increasing number of seizures, the increment being more pronounced in cases. CONCLUSIONS When AED treatment is started at low doses following new-onset seizures, AE reporting does not differ from untreated individuals. Targeting specific factors affecting AE reporting could lead to improved tolerability of epilepsy treatment.
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Kelly PJ, Baker GA, van den Broek MD, Jackson H, Humphries G. The detection of malingering in memory performance: The sensitivity and specificity of four measures in a UK population. BRITISH JOURNAL OF CLINICAL PSYCHOLOGY 2011; 44:333-41. [PMID: 16252435 DOI: 10.1348/014466505x35687] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVES To investigate the validity of a clinical neuropsychological battery for the detection of malingering on tests of memory. METHODS A simulated scenario design was developed to investigate the effectiveness of a battery of four neuropsychological tests in the detection of malingering; the Coin in the Hand Test (CIH), Autobiographical Memory Index (AMI), Rey I 5-Item Test (RIT),and the Wechsler Mental Control Test (MCT). The performances of patients with an acquired brain injury (N = 40) were compared with two groups of controls instructed either to simulate a head injury performance (N = 40) or do their best (N = 40). RESULTS The CIH and MCT demonstrated good validity and displayed high sensitivity and specificity. The RIT and the AMI was relatively poor in distinguishing between simulators and patients. CONCLUSIONS The sensitivity and specificity of all four tests to the detection of malingering has been assessed. Two of the tests the CIH and MCT would be useful as a quick and accurate screening tool for detecting malingering.
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Meador KJ, Baker GA, Browning N, Clayton-Smith J, Combs-Cantrell DT, Cohen M, Kalayjian LA, Kanner A, Liporace JD, Pennell PB, Privitera M, Loring DW. Effects of breastfeeding in children of women taking antiepileptic drugs. Neurology 2010; 75:1954-60. [PMID: 21106960 PMCID: PMC3014232 DOI: 10.1212/wnl.0b013e3181ffe4a9] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Breastfeeding is known to have beneficial effects, but there is concern that breastfeeding during antiepileptic drug (AED) therapy may be harmful to cognitive development. Animal and human studies have demonstrated that some AEDs can adversely affect the immature brain. However, no investigation has examined effects of breastfeeding during AED therapy on subsequent cognitive abilities in children. METHODS The Neurodevelopmental Effects of Antiepileptic Drugs Study is an ongoing prospective multicenter observational investigation of long-term effects of in utero AED exposure on cognition. Between 1999 and 2004, we enrolled pregnant women with epilepsy who were taking a single AED (carbamazepine, lamotrigine, phenytoin, or valproate). We recently reported on differential AED effects on age 3 year cognitive outcomes. In this report, we focus on the effects of breastfeeding during AED therapy on age 3 cognitive outcomes in 199 children. RESULTS A total of 42% of children were breastfed. IQs for breastfed children did not differ from nonbreastfed children for all AEDs combined and for each of the 4 individual AED groups. Mean adjusted IQ scores (95% confidence intervals) across all AEDs were breastfed = 99 (96-103) and nonbreastfed = 98 (95-101). Power was 95% to detect a half SD IQ effect in the combined AED analysis, but was inadequate within groups. CONCLUSIONS This preliminary analysis fails to demonstrate deleterious effects of breastfeeding during AED therapy on cognitive outcomes in children previously exposed in utero. However, caution is advised due to study limitations. Additional research is needed to confirm this observation and extend investigations to other AEDs and polytherapy.
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Mawer G, Briggs M, Baker GA, Bromley R, Coyle H, Eatock J, Kerr L, Kini U, Kuzmyshcheva L, Lucas SB, Wyatt L, Clayton-Smith J. Pregnancy with epilepsy: obstetric and neonatal outcome of a controlled study. Seizure 2009; 19:112-9. [PMID: 20036166 DOI: 10.1016/j.seizure.2009.11.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 11/12/2009] [Accepted: 11/26/2009] [Indexed: 10/20/2022] Open
Abstract
PURPOSE To determine the influence of epilepsy and its treatment on pregnancy and its outcome. DESIGN Controlled, observational study. SETTING National Health Service maternity hospitals in Liverpool and Manchester regions. POPULATION 277 women with epilepsy (WWE) and 315 control women. METHODS WWE were recruited from antenatal clinics. Controls were matched for age and parity but not gestational age. Information was obtained by interview and from clinical records. MAIN OUTCOME MEASURES Obstetric complications, mode of delivery, condition of newborn. RESULTS Distribution of epilepsy syndromes was similar to previous surveys. Most WWE (67%) received monotherapy with carbamazepine, sodium valproate or lamotrigine. Half WWE had no seizures during pregnancy but 34% had tonic clonic seizures. Seizure-related injuries were infrequent. Pregnancies with obstetric complications were increased in women with treated epilepsy (WWTE 45%, controls 33%; p=0.01). Most had normal vaginal delivery (WWTE 63%, controls 61%; p=0.65). Low birth weight was not increased (WWTE 6.2%, controls 5.2%; p=0.69). There were more major congenital malformations (MCM) (WWTE 6.6%, controls 2.1%; p=0.02) and fetal/infant deaths (WWTE 2.2%, controls 0.3%; p=0.09). Amongst monotherapies MCM prevalence was highest with valproate (11.3%; p=0.005). Lamotrigine (5.4%; p=0.23) and carbamazepine (3.0%; p=0.65) were closer to controls (2.1%). There was no association between MCM and dose of folic acid pre-conception. CONCLUSION MCM were more prevalent in the babies of WWTE particularly amongst those receiving sodium valproate.
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Bodde NMG, Brooks JL, Baker GA, Boon PAJM, Hendriksen JGM, Mulder OG, Aldenkamp AP. Psychogenic non-epileptic seizures--definition, etiology, treatment and prognostic issues: a critical review. Seizure 2009; 18:543-53. [PMID: 19682927 DOI: 10.1016/j.seizure.2009.06.006] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2008] [Revised: 04/10/2009] [Accepted: 06/05/2009] [Indexed: 10/20/2022] Open
Abstract
In this review we systematically assess our currently available knowledge about psychogenic non-epileptic seizures (PNES) with an emphasis on the psychological mechanisms that underlie PNES, possibilities for psychological treatment as well as prognosis. Relevant studies were identified by searching the electronic databases. Case reports were not considered. 93 papers were identified; 65 of which were studies. An open non-randomized design, comparing patients with PNES to patients with epilepsy is the dominant design. A working definition for PNES is proposed. With respect to psychological etiology, a heterogeneous set of factors have been identified. Not all factors have a similar impact, though. On the basis of this review we propose a model with several factors that may interact in both the development and prolongation of PNES. These factors involve psychological etiology, vulnerability, shaping, as well as triggering and prolongation factors. A necessary first step of intervention in patients with PNES seems to be explaining the diagnosis with care. Although the evidence for the efficacy of additional treatment strategies is limited, variants of cognitive (behavioural) therapy showed to be the preferred type of treatment for most patients. The exact choice of treatment should be based on individual differences in the underlying factors. Outcome can be measured in terms of seizure occurrence (frequency, severity), but other measures might be of greater importance for the patient. Prognosis is unclear but studies consistently report that 1/3rd to 1/4th of the patients become chronic.
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Snape D, Wang W, Wu J, Jacoby A, Baker GA. Knowledge gaps and uncertainties about epilepsy: findings from an ethnographic study in China. Epilepsy Behav 2009; 14:172-8. [PMID: 18952003 DOI: 10.1016/j.yebeh.2008.09.031] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 09/23/2008] [Accepted: 09/26/2008] [Indexed: 10/21/2022]
Abstract
Epilepsy represents one of the major brain disorders worldwide. In China, research into how much people with epilepsy know about their condition appears limited. Drawing on data collected as part of a large ethnographic study, we present the experiences and views of Chinese people with epilepsy and their family members, to identify knowledge gaps and uncertainties about epilepsy within selected urban and rural communities. We also examine how respondents' demographic characteristics influence their knowledge, understanding, and beliefs about epilepsy. We found knowledge and understanding of epilepsy to be uneven and context specific. Hereditary factors were most frequently cited as a potential cause, although their impact remained unclear. Western medicalization of epilepsy appears less evident in the reports of rural informants, where traditional beliefs continue to shape definitions and treatment. Societal differences within these communities set boundaries on knowledge acquisition. Plotted against these differences, we suggest strategies for proposed educational/psychosocial intervention programs.
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Vinten J, Bromley RL, Taylor J, Adab N, Kini U, Baker GA. The behavioral consequences of exposure to antiepileptic drugs in utero. Epilepsy Behav 2009; 14:197-201. [PMID: 18992367 DOI: 10.1016/j.yebeh.2008.10.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 10/10/2008] [Accepted: 10/11/2008] [Indexed: 10/21/2022]
Abstract
The aim of the study was to examine the behavior of 242 children, aged between 6 and 16 years, born to mothers with epilepsy. Exposure to sodium valproate (VPA) in utero was associated with high levels of parental stress induced by the child's maladaptive behavior. These children were also poorer for daily living skills and skills relating to socialization. The outcomes on both measures were strongly affected by the Full Scale IQ (FSIQ) of the child; however, no significant differences were found between the groups and therefore this pattern of results cannot simply be attributed to a lower FSIQ. The results of this study suggest that exposure to VPA in utero and the presence of a lowered FSIQ are risk factors for the development of poorer adaptive behavior and a higher rate of maladaptive behaviors.
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Bromley RL, Mawer G, Clayton-Smith J, Baker GA. Autism spectrum disorders following in utero exposure to antiepileptic drugs. Neurology 2008; 71:1923-4. [PMID: 19047565 DOI: 10.1212/01.wnl.0000339399.64213.1a] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Marson AG, Appleton R, Baker GA, Chadwick DW, Doughty J, Eaton B, Gamble C, Jacoby A, Shackley P, Smith DF, Tudur-Smith C, Vanoli A, Williamson PR. A randomised controlled trial examining the longer-term outcomes of standard versus new antiepileptic drugs. The SANAD trial. Health Technol Assess 2007; 11:iii-iv, ix-x, 1-134. [PMID: 17903391 DOI: 10.3310/hta11370] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES To compare clinicians' choice of one of the standard epilepsy drug treatments (carbamazepine or valproate) versus appropriate comparator new drugs. DESIGN A clinical trial comprising two arms, one comparing new drugs in carbamazepine and the other with valproate. SETTING A multicentre study recruiting patients with epilepsy from hospital outpatient clinics. PARTICIPANTS Patients with an adequately documented history of two or more clinically definite unprovoked epileptic seizures within the last year for whom treatment with a single antiepileptic drug represented the best therapeutic option. INTERVENTIONS Arm A was carbamazepine (CBZ) versus gabapentin (GBP) versus lamotrigine (LTG) versus oxcarbazepine (OXC) versus topiramate (TPM). Arm B valproate (VPS) versus LTG versus TPM. MAIN OUTCOME MEASURES Time to treatment failure (withdrawal of the randomised drug for reasons of unacceptable adverse events or inadequate seizure control or a combination of the two) and time to achieve a 12-month remission of seizures. Time from randomisation to first seizure, 24-month remission of seizures, incidence of clinically important adverse events, quality of life (QoL) outcomes and health economic outcomes were also considered. RESULTS Arm A recruited 1721 patients (88% with symptomatic or cryptogenic partial epilepsy and 10% with unclassified epilepsy). Arm B recruited 716 patients (63% with idiopathic generalised epilepsy and 25% with unclassified epilepsy). In Arm A LTG had the lowest incidence of treatment failure and was statistically superior to all drugs for this outcome with the exception of OXC. Some 12% and 8% fewer patients experienced treatment failure on LTG than CBZ, the standard drug, at 1 and 2 years after randomisation, respectively. The superiority of LTG over CBZ was due to its better tolerability but there is satisfactory evidence indicating that LTG is not clinically inferior to CBZ for measures of its efficacy. No consistent differences in QoL outcomes were found between treatment groups. Health economic analysis supported LTG being preferred to CBZ for both cost per seizure avoided and cost per quality-adjusted life-year gained. In Arm B for time to treatment failure, VPS, the standard drug, was preferred to both TPM and LTG, as it was the drug least likely to be associated with treatment failure for inadequate seizure control and was the preferred drug for time to achieving a 12-month remission. QoL assessments did not show any between-treatment differences. The health economic assessment supported the conclusion that VPS should remain the drug of first choice for idiopathic generalised or unclassified epilepsy, although there is a suggestion that TPM is a cost-effective alternative to VPS. CONCLUSIONS The evidence suggests that LTG may be a clinical and cost-effective alternative to the existing standard drug treatment, CBZ, for patients diagnosed as having partial seizures. For patients with idiopathic generalised epilepsy or difficult to classify epilepsy, VPS remains the clinically most effective drug, although TPM may be a cost-effective alternative for some patients. Three new antiepileptic drugs have recently been licensed in the UK for the treatment of epilepsy (levetiracetam, zonisamide and pregabalin), therefore these drugs should be compared in a similarly designed trial.
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McEwan L, Taylor J, Casswell M, Entwistle R, Jacoby K, Gorry J, Jacoby A, Baker GA. Knowledge of and attitudes expressed toward epilepsy by carers of people with epilepsy: a UK perspective. Epilepsy Behav 2007; 11:13-9. [PMID: 17544332 DOI: 10.1016/j.yebeh.2007.02.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 02/08/2007] [Accepted: 02/11/2007] [Indexed: 11/19/2022]
Abstract
OBJECTIVE The aim of this study was to investigate the knowledge and attitudes possessed by carers of people with epilepsy. METHODS A postal survey of 2000 carers recruited from the membership list of a UK epilepsy charity was conducted using a standard set of questions. The questions covered their knowledge of epilepsy (e.g., estimating prevalence and identifying causes of epilepsy) and their attitudes (e.g., about the characteristics of people with epilepsy). RESULTS Overall, 651 carers responded. Only 29% of carers were male, with the majority between 40 and 60 years of age. The majority of respondents (76%) overestimated the prevalence of epilepsy. Twenty-five percent believed that epilepsy was caused by stress. The majority of respondents believed that people with epilepsy were treated differently by others. Only a small percentage believed that people with epilepsy should be barred from such professions as teaching and nursing. CONCLUSIONS Carers of people with epilepsy generally possessed high levels of knowledge about most aspects of epilepsy, and their attitudes toward those with epilepsy were benign. There were, however, particular groups who were more likely to hold more positive attitudes, and these included younger and better-educated individuals. Limitations of this study include that the sample was self-selected and that only a third of the people to whom the questionnaire was mailed responded.
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Shaw EJ, Stokes T, Camosso-Stefinovic J, Baker R, Baker GA, Jacoby A. Self-management education for adults with epilepsy. Cochrane Database Syst Rev 2007:CD004723. [PMID: 17443553 DOI: 10.1002/14651858.cd004723.pub2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Self-management education has been shown to improve the quality of life of people with chronic illnesses. It has been suggested that self-management education may improve seizure control and other outcomes in people with epilepsy. OBJECTIVES To review systematically the research literature on the effectiveness of self-management education in improving health outcomes for adults with epilepsy. SEARCH STRATEGY We searched MEDLINE (Ovid) (1966 to April 2005), EMBASE (Ovid) (1980 to April 2005), CINAHL (Dialog) (1980 to April 2005), PsycINFO (Dialog) (1887 to April 2005), and the Cochrane Epilepsy Group's Specialised Register (April 2005). We also handsearched Epilepsia and conference abstracts and proceedings. Experts in the field were contacted to identify any additional trials. We did not impose any language restriction. We re-ran the searches in February 2007 and added the identified references to the 'Studies awaiting assessment' table. SELECTION CRITERIA Randomised trials of self-management education programmes for adults with epilepsy. DATA COLLECTION AND ANALYSIS At least two review authors independently assessed the quality of each study and extracted data. MAIN RESULTS Two trials evaluated the effect of self-management education for adults with epilepsy, neither of which assessed as being of high quality. In total, 483 adults with epilepsy were randomised. Both trials showed improvements in seizure frequency and other outcomes, such as knowledge. However, we were not able to estimate a summary effect for seizure frequency due to a lack of data. AUTHORS' CONCLUSIONS Self-management education programmes, based on increasing understanding through psychosocial methods, may improve knowledge about epilepsy, certain behavioural outcomes, and reduce seizure frequency. It is, however, not clear how effective self-management programmes of epilepsy would be in a more general population of adults with epilepsy, as both trials had higher proportions of people with partial seizures than would be expected in a community sample.
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Stokes T, Shaw EJ, Camosso-Stefinovic J, Baker R, Baker GA, Jacoby A. Self-management education for children with epilepsy. Cochrane Database Syst Rev 2007:CD004724. [PMID: 17443554 DOI: 10.1002/14651858.cd004724.pub2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND Self-management education has been shown to improve the quality of life of children and young people with chronic illnesses. It has been suggested that self-management education may improve seizure control and other outcomes in children and young people with epilepsy. OBJECTIVES To review systematically the research literature on the effectiveness of self-management education in improving health outcomes for children and young people with epilepsy. SEARCH STRATEGY We searched the Cochrane Epilepsy Group's Specialised Register (April 2007), MEDLINE (Ovid) (1966 to February 2007), EMBASE (Ovid) (1980 to February 2007), CINAHL (Dialog) (1980 to February 2007), and PsycINFO (Dialog) (1887 to February 2007). We also handsearched Epilepsia and conference abstracts and proceedings. Experts in the field were contacted to identify any additional trials. No language restriction was imposed. SELECTION CRITERIA Randomised trials of self-management education programmes for children or young people with epilepsy. DATA COLLECTION AND ANALYSIS At least two review authors independently assessed the quality of each study and extracted data. MAIN RESULTS Only one trial involving 167 children was identified that evaluated the effect of a child-centred model of training for the self-management of two chronic illnesses, asthma and epilepsy. The trial was not assessed as being of high quality and the methods used to analyse and report the data did not enable us to precisely determine the effect of the intervention. However, improvements were seen in seizure frequency and other outcomes, such as knowledge and behaviour. AUTHORS' CONCLUSIONS Self-management education programmes that deliver a child-centred model of training, may improve knowledge about epilepsy, certain behavioural outcomes, and reduce seizure frequency in children and young people with epilepsy. However, based on the evidence reviewed, we are not able to determine how effective it is, or what the key components of the programme should be.
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Baker GA, Brooks JL, Goodfellow L, Bodde N, Aldenkamp A. Treatments for non-epileptic attack disorder. Cochrane Database Syst Rev 2007:CD006370. [PMID: 17253591 DOI: 10.1002/14651858.cd006370] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Psychogenic non-epileptic seizures (NES) have the outward appearance of epilepsy in the absence of physiological or electroencephalographic correlates. Non-epileptic seizures can occur in isolation or in combination with epileptic seizures. The development and maintenance of non-epileptic seizures has been well documented and there is a growing literature on the treatment of NES which includes non-psychological (including anti-anxiety and antidepressant pharmacological treatment) and psychological therapies (including cognitive behavioural therapy (CBT), hypnotherapy and paradoxical therapy). Various treatment methodologies have been tried with variable success. The purpose of this Cochrane review was to establish the evidence base for the treatment of NES. OBJECTIVES To assess whether treatments for NES result in a reduction in frequency of seizures and/or improvement in quality of life, and whether any treatment is significantly more effective than others. SEARCH STRATEGY We searched the Cochrane Epilepsy Group's Specialised Register (September 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2005), MEDLINE (1966 to July 2005), and PsycINFO (1806 to July 2005). No language restrictions were imposed. We checked the reference lists of retrieved studies for additional reports of relevant studies SELECTION CRITERIA Randomised or quasi-randomised studies were included that assessed one or more types of psychological or non-psychological interventions for the treatment of NES. Studies of childhood NES were excluded from our review. DATA COLLECTION AND ANALYSIS Three review authors independently assessed the trials for inclusion and extracted data. Outcomes included reduction in seizure frequency and improvements in quality of life. MAIN RESULTS Three small studies met our inclusion criteria and were of poor methodological quality. Two assessed hypnosis and the other paradoxical therapy. There were no detailed reports of improved seizure frequency or quality of life outcomes, and these trials provide no reliable evidence of a beneficial effect of these interventions. AUTHORS' CONCLUSIONS In view of the methodological limitations and the small number of studies, we have no reliable evidence to support the use of any treatment including hypnosis or paradoxical injunction therapy in the treatment of NES. Randomised studies of these and other interventions are needed.
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Ohki S, Baker GA, Page PM, McCarty TA, Epand RM, Bright FV. Interaction of influenza virus fusion peptide with lipid membranes: effect of lysolipid. J Membr Biol 2006; 211:191-200. [PMID: 17091213 DOI: 10.1007/s00232-006-0862-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2006] [Revised: 07/12/2006] [Indexed: 11/29/2022]
Abstract
The effect of lysophosphatidylcholine (LPC) on lipid vesicle fusion and leakage induced by influenza virus fusion peptides and the peptide interaction with lipid membranes were studied by using fluorescence spectroscopy and monolayer surface tension measurements. It was confirmed that the wild-type fusion peptide-induced vesicle fusion rate increased several-fold between pH 7 and 5, unlike a mutated peptide, in which valine residues were substituted for glutamic acid residues at positions 11 and 15. This mutated peptide exhibited a much greater ability to induce lipid vesicle fusion and leakage but in a less pH-dependent manner compared to the wild-type fusion peptide. The peptide-induced vesicle fusion and leakage were well correlated with the degree of interaction of these peptides with lipid membranes, as deduced from the rotational correlation time obtained for the peptide tryptophan fluorescence. Both vesicle fusion and leakage induced by the peptides were suppressed by LPC incorporated into lipid vesicle membranes in a concentration-dependent manner. The rotational correlation time associated with the peptide's tryptophan residue, which interacts with lipid membranes containing up to 25 mole % LPC, was virtually the same compared to lipid membranes without LPC, indicating that LPC-incorporated membrane did not affect the peptide interaction with the membrane. The adsorption of peptide onto a lipid monolayer also showed that the presence of LPC did not affect peptide adsorption.
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