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1.
BMC Neurol ; 22(1): 245, 2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35790912

ABSTRACT

BACKGROUND: Patient involvement in discharge planning of patients with stroke can be accomplished by providing personalized outcome information and promoting shared decision-making. The aim of this study was to develop a patient decision aid (PtDA) for discharge planning of hospitalized patients with stroke. METHODS: A convergent mixed methods design was used, starting with needs assessments among patients with stroke and health care professionals (HCPs). Results of these assessments were used to develop the PtDA with integrated outcome information in several co-creation sessions. Subsequently, acceptability and usability were tested to optimize the PtDA. Development was guided by the International Patient Decision Aids Standards (IPDAS) criteria. RESULTS: In total, 74 patients and 111 HCPs participated in this study. A three-component PtDA was developed, consisting of: 1) a printed consultation sheet to introduce the options for discharge destinations, containing information that can be specified for each individual patient; 2) an online information and deliberation tool to support patient education and clarification of patient values, containing an integrated "patients-like-me" model with outcome information about discharge destinations; 3) a summary sheet to support actual decision-making during consultation, containing the patient's values and preferences concerning discharge planning. In the acceptability test, all qualifying and certifying IPDAS criteria were fulfilled. The usability test showed that patients and HCPs highly appreciated the PtDA with integrated outcome information. CONCLUSIONS: The developed PtDA was found acceptable and usable by patients and HCPs and is currently under investigation in a clinical trial to determine its effectiveness.


Subject(s)
Patient Discharge , Stroke , Decision Support Techniques , Health Personnel , Humans , Patients , Stroke/therapy
2.
Qual Life Res ; 31(12): 3317-3330, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35622294

ABSTRACT

PURPOSE: This study aims to systematically review and critically appraise the content validity of the adult versions of the Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS-PF) item bank and its derivative measures in any adult population. METHODS: MEDLINE and EMBASE were searched in October 2021 for studies on measurement properties of PROMIS-PF measures in an adult population. Studies were included if the study described the development of a PROMIS-PF measure or investigated its relevance, comprehensiveness, or comprehensibility. Assessment of the methodological quality of eligible studies, rating of results, and summarizing evidence was performed following the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology for assessing content validity. A modified GRADE approach was used to determine the level of evidence. RESULTS: Three development studies and eight studies on the content validity of one or more of the PROMIS-PF measures were identified. The methodological quality of most studies was rated doubtful. There was low to high level evidence for sufficient relevance, comprehensiveness, and comprehensibility of most PROMIS-PF measures for healthy seniors and various disease populations. We found low to moderate level evidence for insufficient relevance of PROMIS-PF measures for patients with conditions that affected only one body part, and insufficient comprehensibility of the PROMIS-PF measures for minority elderly. CONCLUSION: Most PROMIS-PF measures demonstrate sufficient content validity in healthy seniors and various disease populations. However, the quality of this evidence is generally low to moderate, due to limitations in the methodological quality of the studies.


Subject(s)
Patient Reported Outcome Measures , Quality of Life , Adult , Humans , Aged , Quality of Life/psychology , Consensus , Health Status , Information Systems
3.
Arch Phys Med Rehabil ; 103(8): 1582-1591, 2022 08.
Article in English | MEDLINE | ID: mdl-34998711

ABSTRACT

OBJECTIVE: The present study aimed to create a shorter version of the Action Research Arm Test (ARAT) without compromising its measurement properties. DESIGN: Secondary analysis of stroke recovery cohorts that used the ARAT to measure upper limb impairment. SETTING: Rehabilitation centers. PARTICIPANTS: Patients with stroke from 5 different stroke recovery cohorts (N=1425). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: A decision tree version of the ARAT (ARAT-DT) was developed using chi-square automated interaction detection. In an independent validation subset, criterion validity, agreement of ARAT-DT with original ARAT scores and score categories, and construct validity with the Fugl-Meyer Upper Extremity Scale score were determined. RESULTS: In total, 3738 ARAT measurements were available involving 1425 subjects. Chi-square automated interaction detection analysis in the development subset (n=2803) revealed an optimized decision tree with a maximum of 4 consecutive items. In the validation data set (n=935), the ARAT-DT differed by a mean of 0.19 points (0.3% of the total scale) from the original ARAT scores (limits of agreement=-5.67 to 6.05). The ARAT-DT demonstrated excellent criterion validity with the original ARAT scores (intraclass correlation coefficient=0.99 and ρ=0.99) and scoring categories (κw=0.97). The ARAT-DT showed very good construct validity with the Fugl-Meyer Upper Extremity Scale (ρ=0.92). CONCLUSION: A decision tree version of the ARAT was developed, reducing the maximum number of items necessary for ARAT administration from 19 to 4. The scores produced by the decision tree had excellent criterion validity with original ARAT scores.


Subject(s)
Stroke Rehabilitation , Stroke , Decision Trees , Disability Evaluation , Health Services Research , Humans , Recovery of Function , Stroke/complications , Upper Extremity
4.
Patient Educ Couns ; 105(5): 1123-1129, 2022 05.
Article in English | MEDLINE | ID: mdl-34462248

ABSTRACT

OBJECTIVE: The aim of this study was to gain insight into experiences of patients with acute stroke regarding information provision and their preferred involvement in decision-making processes during the initial period of hospitalisation. METHODS: A sequential explanatory design was used in two independent cohorts of patients with stroke, starting with a survey after discharge from hospital (cohort 1) followed by observations and structured interviews during hospitalisation (cohort 2). Quantitative data were analysed descriptively. RESULTS: In total, 72 patients participated in this study (52 in cohort 1 and 20 in cohort 2). During hospitalisation, the majority of the patients were educated about acute stroke and their treatment. Approximately half of the patients preferred to have an active role in the decision-making process, whereas only 21% reported to be actively involved. In cohort 2, 60% of the patients considered themselves capable to carefully consider treatment options. CONCLUSIONS: Active involvement in the acute decision-making process is preferred by approximately half of the patients with acute stroke and most of them consider themselves capable of doing so. However, they experience a limited degree of actual involvement. PRACTICE IMPLICATIONS: Physicians can facilitate patient engagement by explicitly emphasising when a decision has to be made in which the patient's opinion is important.


Subject(s)
Decision Making , Stroke , Hospitalization , Humans , Patient Participation , Stroke/therapy , Surveys and Questionnaires
5.
BMC Health Serv Res ; 21(1): 1350, 2021 Dec 18.
Article in English | MEDLINE | ID: mdl-34922534

ABSTRACT

INTRODUCTION: Approximately two-thirds of the patients admitted to the hospital with an ischemic stroke are discharged directly home. Discontinuity of care may result in avoidable patient harm, re-admissions and even death. We hypothesized that the transfer of information is most essential in this patient group since any future care for these patients relies solely on the information that is available to the care provider responsible at that time. AIM: The objective of this study was to evaluate the continuity of transmural care in ischemic stroke patients by assessing 1) the transfer of clinical information through discharge letters to general practitioners (GPs), 2) subsequent documentation of this information and early follow-up by GPs and 3) the documentation of medication-related information in discharge letters, at GPs and community pharmacies (CPs). METHODS: This prospective cohort study was conducted from September 2019 through March 2020 in OLVG, Amsterdam, the Netherlands, in patients with a first stroke discharged directly home. Outcome measures were derived from national guidelines and regional agreements. Results were analyzed using descriptive analysis. RESULTS: A total of 33 patients were included. Discharge letters (n = 33) and outpatient clinic letters (n = 24) to GPs contained most of the essential items, but 16% (n = 9) of the letters were sent in time. GPs (n = 31) infrequently adhered to guidelines since 10% (n = 3) of the diagnoses were registered using the correct code and 55% (n = 17) of the patients received follow-up shortly after discharge. Medication overviews were inaccurately communicated to GPs since 62% (n = 150) of all prescriptions (n = 243) were correctly noted in the discharge letter. Further loss of information was seen as only 39% (n = 95) of all prescriptions were documented correctly in GP overviews. We found that 59% (n = 144) of the prescriptions were documented correctly in CP overviews. CONCLUSION: In this study, we found that discontinuity of care occurred to a varying extent throughout transmural care in patients with a first stroke who were discharged home.


Subject(s)
Patient Discharge , Stroke , Humans , Netherlands , Patient Transfer , Prospective Studies , Stroke/therapy
6.
J Neurol ; 268(2): 403-408, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32691235

ABSTRACT

BACKGROUND AND PURPOSE: There are concerns that the coronavirus disease 2019 (COVID-19) outbreak negatively affects the quality of care for acute cardiovascular conditions. We assessed the impact of the COVID-19 outbreak on trends in hospital admissions and workflow parameters of acute stroke care in Amsterdam, The Netherlands. METHODS: We used data from the three hospitals that provide acute stroke care for the Amsterdam region. We compared two 7-week periods: one during the peak of the COVID-19 outbreak (March 16th-May 3th 2020) and one prior to the outbreak (October 21st-December 8th 2019). We included consecutive patients who presented to the emergency departments with a suspected stroke and assessed the change in number of patients as an incidence-rate ratio (IRR) using a Poisson regression analysis. Other outcomes were the IRR for stroke subtypes, change in use of reperfusion therapy, treatment times, and in-hospital complications. RESULTS: During the COVID-19 period, 309 patients presented with a suspected stroke compared to 407 patients in the pre-COVID-19 period (IRR 0.76 95%CI 0.65-0.88). The proportion of men was higher during the COVID-19 period (59% vs. 47%, p < 0.001). There was no change in the proportion of stroke patients treated with intravenous thrombolysis (28% vs. 30%, p = 0.58) or endovascular thrombectomy (11% vs 12%, p = 0.82) or associated treatment times. Seven patients (all ischemic strokes) were diagnosed with COVID-19. CONCLUSION: We observed a 24% decrease in suspected stroke presentations during the COVID-19 outbreak, but no evidence for a decrease in quality of acute stroke care.


Subject(s)
COVID-19 , Pandemics , Stroke/therapy , Aged , Aged, 80 and over , COVID-19/epidemiology , Emergency Medical Services , Female , Hospitalization , Humans , Incidence , Ischemic Stroke/complications , Ischemic Stroke/epidemiology , Male , Middle Aged , Netherlands/epidemiology , Poisson Distribution , Quality of Health Care , Reperfusion , Retrospective Studies , Stroke/complications , Stroke/epidemiology , Thrombectomy/statistics & numerical data , Thrombolytic Therapy/statistics & numerical data , Time-to-Treatment , Treatment Outcome
7.
BMC Health Serv Res ; 20(1): 1049, 2020 Nov 17.
Article in English | MEDLINE | ID: mdl-33203405

ABSTRACT

BACKGROUND: Ischemic stroke patients with a good outcome in terms of motor functioning and communication are likely to be discharged home without further rehabilitation. A significant number of these patients experience cognitive and emotional problems resulting in lower quality of life and decreased participation in society. This paper presents the protocol of a study examining the clinical effectiveness, cost-effectiveness and implementation of an intervention focused on screening and patient-tailored care for cognitive and emotional problems as compared to usual care in patients discharged home after ischemic stroke. METHODS / DESIGN: A multicenter, patient-blinded, cluster randomized controlled trial will be performed. Centers will be randomized (1:1) to the intervention group or the usual care group. Patients (> 18 years old) with a neurological confirmed diagnosis of ischemic stroke who can be discharged home without follow-up treatment at an outpatient rehabilitation clinic will be included. In the intervention group, patients will receive a short, individualized, semi-structured consultation by specialized nurses in addition to usual care. This consultation includes 1) screening for cognitive and emotional problems, 2) screening for restrictions in participation, 3) promotion of self-management strategies and 4) a decision tool for referral to rehabilitation services. The intervention will be performed approximately 6 weeks after the stroke at the neurology outpatient clinics and will take approximately 60 min. The control group will receive care as usual. Both groups will be followed-up at 6 weeks, 3 months and 12 months after stroke. The primary outcome will be the level of participation measured with the Restriction subscale of the Utrecht Scale for Evaluation of Rehabilitation on the level of Participation (USER-Participation-R) at 12 months. A cost-effectiveness analysis and process evaluation will be performed alongside. DISCUSSION: This trial is the first to evaluate clinical effectiveness, cost-effectiveness and implementation of screening and patient-tailored care for cognitive and emotional problems compared to care as usual in patients discharged home after ischemic stroke. Potentially, this will improve the outcomes for patients with frequently occurring cognitive and emotional problems after stroke. TRIAL REGISTRATION: Netherlands Trial Register: NL7295 , registered 25 September 2018.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke Rehabilitation , Stroke , Adolescent , Cognition , Cost-Benefit Analysis , Humans , Multicenter Studies as Topic , Netherlands , Patient Discharge , Quality of Life , Randomized Controlled Trials as Topic , Stroke/therapy
8.
J Neurol Sci ; 394: 132-137, 2018 11 15.
Article in English | MEDLINE | ID: mdl-30261428

ABSTRACT

INTRODUCTION: Patients with complete occlusion of the internal carotid artery (CAO) are vulnerable to cerebral hypoperfusion. Since cerebral hypoperfusion is associated with accelerated cognitive decline, patients with CAO may have an increased risk of cognitive impairment. We aimed to assess the prevalence and profile of cognitive impairment in patients with CAO and to explore the relation between hemodynamic impairment and cognitive functioning. METHODS: We systematically searched Medline and EMBASE for studies including patients with symptomatic or asymptomatic CAO subjected to cognitive testing that were published between 1980 and 2017. We did not include patients with carotid stenosis. We obtained data on type of study, patient characteristics, cerebral imaging and neuropsychological testing. In addition, we extracted data on potential causes of systemic hemodynamic impairment and the presence and stage of cerebral hemodynamic impairment. We assessed methodological quality of included studies with the Newcastle-Ottawa Scale. RESULTS: We found eight studies comprising 244 patients (mean age 61 years, 76% male, 93% symptomatic CAO). The proportion of patients with cognitive impairment ranged from 54 to 71% in four studies; in the other four studies patients with CAO performed worse on cognitive testing than controls, but results were not quantified. Impairment was reported in all cognitive domains. We found no data on the association between systemic hemodynamic impairment and cognitive functioning. Studies that assessed whether cerebral hemodynamic impairment was associated with cognitive functioning showed conflicting results. CONCLUSION: In patients with CAO, cognitive impairment is present in about half to two-thirds of patients and is not restricted to specific cognitive domains. The effect of systemic and cerebral hemodynamic impairment on cognitive functioning in patients with CAO deserves further study.


Subject(s)
Carotid Stenosis/complications , Cognition Disorders/etiology , Databases, Bibliographic/statistics & numerical data , Humans
9.
Ned Tijdschr Geneeskd ; 161: D826, 2017.
Article in Dutch | MEDLINE | ID: mdl-28378696

ABSTRACT

BACKGROUND: Carotid sinus massage is a widely used method for diagnosis and treatment of supraventricular tachycardia and carotid sinus hypersensitivity. Complications, mostly neurological, can occur but are rare. Carotid stenosis is a risk factor for complications. Hearing a carotid bruit on auscultation indicates stenosis, and is a contraindication for performing carotid sinus massage. However, the sensitivity of auscultation is insufficient. CASE DESCRIPTION: A 71-year-old man with a history of hypertension and hypercholesterolemia presented to the cardiology accident and emergency department with palpitations. A supraventricular tachycardia was found on examination, for which carotid sinus massage was performed. The patient developed severe aphasia and right-sided hemiparesis caused by an extensive stroke, and died a few days later. CONCLUSION: The chance of complications following carotid sinus massage is slight; however, this type of complication can have severe consequences. Safer alternative methods may be used for patients with supraventricular tachycardia. In older patients with vascular risk factors, more extensive diagnostic investigations for carotid stenosis should be considered in the diagnostic workup for carotid sinus hypersensitivity.


Subject(s)
Carotid Sinus/physiopathology , Massage , Stroke/etiology , Aged , Carotid Arteries , Humans , Male , Syncope
10.
NeuroRehabilitation ; 34(3): 401-7, 2014.
Article in English | MEDLINE | ID: mdl-24473242

ABSTRACT

BACKGROUND: Despite the beneficial effect of cardiac rehabilitation after myocardial infarction, a rehabilitation program to improve cardiorespiratory fitness and influence secondary prevention has not been implemented for ischemic stroke and transient ischemic attack (TIA). OBJECTIVE: To investigate the safety and feasibility of a post-stroke care including an exercise program after minor ischemic stroke or TIA. METHODS: In a randomised controlled trial, 20 patients with a recent minor stroke or TIA without cardiac contraindications were randomly assigned to one of the two interventions; post-stroke care without exercise or post-stroke care with exercise. Patients were evaluated at baseline, 6 and 12 months. RESULTS: Eighteen patients completed the intervention. In none of the patients cardiopulmonary contraindications for the maximal exercise test and exercise program were found. No cardiovascular events occurred during the maximal exercise tests and exercise program. After one year, significantly more patients in the post-stroke care with exercise group achieved the composite endpoint of optimal medical therapy. CONCLUSIONS: Post-stroke care including an exercise program is safe and feasible in the acute phase after minor stroke or TIA and might be a way to increase effectiveness of secondary stroke prevention. We are currently conducting a larger trial to validate these results.


Subject(s)
Exercise Therapy , Ischemic Attack, Transient/rehabilitation , Physical Fitness , Secondary Prevention/methods , Stroke Rehabilitation , Aged , Exercise Test , Feasibility Studies , Female , Humans , Male , Middle Aged , Motivation , Risk Factors
11.
BMJ Open ; 4(12): e007065, 2014 Dec 31.
Article in English | MEDLINE | ID: mdl-25552615

ABSTRACT

INTRODUCTION: Patients with transient ischaemic attack (TIA) or stroke are at risk for cognitive impairment and dementia. Currently, there is no known effective strategy to prevent this cognitive decline. Increasing evidence exists that physical exercise is beneficial for cognitive function. However, in patients with TIA or stroke who are at risk of cognitive impairment and dementia, only a few trials have been conducted. In this study, we aim to investigate whether a physical exercise programme (MoveIT) can prevent cognitive decline in patients in the acute phase after a TIA or minor ischaemic stroke. METHODS AND ANALYSIS: A single-blinded randomised controlled trial will be conducted to investigate the effect of an aerobic exercise programme on cognition compared with usual care. 120 adult patients with a TIA or minor ischaemic stroke less than 1 month ago will be randomly allocated to an exercise programme consisting of a 12-week aerobic exercise programme and regular follow-up visits to a specialised physiotherapist during the period of 1 year or to usual care. Outcome measures will be assessed at the baseline, and at the 1-year and 2-year follow-up. The primary outcome is cognitive functioning measured with the Montreal Cognitive Assessment (MoCA) test and with additional neuropsychological tests. Secondary outcomes include maximal exercise capacity, self-reported physical activity and measures of secondary prevention. ETHICS AND DISSEMINATION: The study received ethical approval from the VU University Amsterdam Ethics committee (2011/383). The results of this study will be published in peer-reviewed journals and presented at international conferences. We will also disseminate the main results to our participants in a letter. TRIAL REGISTRATION NUMBER: The Nederlands Trial Register NTR3884.


Subject(s)
Cognition Disorders/prevention & control , Exercise Therapy/methods , Ischemic Attack, Transient/complications , Stroke/complications , Adult , Female , Humans , Male , Secondary Prevention/methods , Single-Blind Method
12.
Anal Bioanal Chem ; 404(6-7): 1803-11, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22899246

ABSTRACT

In the last few years, an increasing number of dried blood spot (DBS) sampling assays have been developed. With this increase, more insight is gained in the factors that possibly influence the performance of DBS assays. We have developed an assay for four commonly used immunosuppressants; some of them are possibly concomitantly prescribed: cyclosporin A (CsA), tacrolimus (TcR), sirolimus (SiR), and everolimus (EvE). Chromatographic separation from possible ion suppression was obtained within the total runtime of 4.2 min. Trifluoroacetic acid and ammonium acetate were used as mobile phase additives. The linearity ranged from 23.6 to 787, 1.14 to 30.3, 1.34 to 35.8, and 1.26 to 33.7 µg/L, for CsA, TcR, SiR, and EvE, respectively. Between- and within-run accuracy and precision were all within 15 % and extensive validation for DBS samples, such as hematocrit, blood spot volume, and spot punch location was performed. None of these factors were found to be of influence on the performance of the DBS assay.


Subject(s)
Chromatography, Liquid/methods , Cyclosporine/blood , Dried Blood Spot Testing/methods , Immunosuppressive Agents/blood , Sirolimus/analogs & derivatives , Sirolimus/blood , Tacrolimus/blood , Tandem Mass Spectrometry/methods , Everolimus , Humans
13.
Water Sci Technol ; 63(8): 1765-71, 2011.
Article in English | MEDLINE | ID: mdl-21866779

ABSTRACT

The biological treatment of wastewater could yield high energy fuels such as methane and alcohols, however most conventional treatment systems do not recover this energy potential. with a simple model of the energy yields of various wastewater treatment technologies it is possible to demonstrate how minor shifts in technology selection can lead the industry from being identified as predominantly energy intensive, to being recognised as a source of energy resources. The future potential energy yield is estimated by applying energy yield factors to alternative use scenarios of the same wastewater loads. The method for identifying the energy potential of wastewater was demonstrated for the New Zealand wastewater sector, but can equally be applied to other countries or regions. The model suggests that by using technologies that maximise the recovery of energy from wastewater, the potential energy yield from this sector would be substantially increased (six fold for New Zealand).


Subject(s)
Bioelectric Energy Sources , Biofuels , Waste Disposal, Fluid/methods , Alcohols , Anaerobiosis , Conservation of Energy Resources/methods , Eukaryota/metabolism , Fermentation
14.
Neurology ; 75(9): 818-25, 2010 Aug 31.
Article in English | MEDLINE | ID: mdl-20805527

ABSTRACT

OBJECTIVE: Identification and examination of all patients with multifocal motor neuropathy (MMN) in the Netherlands to document the clinical spectrum and response to IV immunoglobulin (IVIg) and to determine correlates of outcome. METHODS: A national cross-sectional descriptive study was performed. Ninety-seven patients were identified; 88 participated. Logistic regression analysis was used to study determinants of outcome. RESULTS: Age at onset was younger in men than in women (38 vs 45 years, p = 0.05). Onset of weakness was in distal arm (61%) or distal leg (34%), and occasionally in the upper arm (5%). Initial diagnosis was motor neuron disease in one-third of patients. Brisk, but not pathologic, reflexes in weakened muscles were found in 8%. Conduction blocks were most frequently detected in the ulnar (80%) and median (77%) nerves, but occasionally only between Erb and axilla (6%), or in the musculocutaneous nerve (1%). Ninety-four percent responded to IVIg therapy: nonresponders had longer disease duration before the first treatment (p = 0.03). Seventy-six percent received IVIg maintenance treatment at the time of this study (median duration 6 years; range 0-17): the median dose increased over the years from 12 to 17 g per week (p < 0.01). Independent determinants of more severe weakness and disability were axon loss (p < 0.001; p < 0.0001) and longer disease duration without IVIg (p = 0.03; p = 0.07). CONCLUSION: The results of this study may help aid recognition the clinical picture of MMN. Early IVIg treatment may help to postpone axonal degeneration and permanent deficits. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that IVIg improves muscle strength of patients with MMN and disability (defined as an increase of >or=1 Medical Research Council grade in at least 2 muscle groups without decrease in other muscle groups) in 94% (95% confidence interval, 86.8%-97.4%) of patients.


Subject(s)
Immunoglobulins, Intravenous/administration & dosage , Motor Neuron Disease/drug therapy , Motor Neuron Disease/physiopathology , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Muscle Fatigue/drug effects , Muscle Fatigue/physiology , Neural Conduction/drug effects , Neural Conduction/physiology , Treatment Outcome
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 878(19): 1437-42, 2010 Jun 01.
Article in English | MEDLINE | ID: mdl-20399153

ABSTRACT

BACKGROUND: Monitoring of thiopurine metabolites 6-thioguanine nucleotides (6-TGN) and 6-methylmercaptopurine (6-MMP) is used to assess compliance and explain adverse reactions in IBD-patients. Correlations between dosage, metabolite concentrations and therapeutic efficacy or toxicity are contradictive. Research is complicated by analytical problems as matrices analyzed and analytical procedures vary widely. Moreover, stability of thiopurine metabolites is not well documented, yet pivotal for interpretation of analytical outcomes. Therefore, we prospectively investigated metabolite stability in blood samples under standard storage conditions. METHODS: Stability at room temperature and refrigeration (22 degrees C, 4 degrees C) was investigated during 1 week and frozen samples (-20 degrees C, -80 degrees C) were analyzed during 6 months storage. Ten patient samples were analyzed for each study period. RESULTS: Median 6-TGN concentrations on day 7 decreased significantly to 53% and 90% during storage at ambient temperature or refrigeration. Median 6-MMP concentrations on day 7 decreased significantly to 55% and 86%, respectively. Samples stored at -20 degrees C also showed significant decreases in both 6-TGN and 6-MMP in comparison with baseline values. At -80 degrees C, only 6-MMP showed a significant decrease in values compared to baseline. CONCLUSION: The stability of thiopurine metabolites is clearly a limiting factor in studies investigating utilisation of TDM and correlations with therapeutic outcome in IBD-patients. This has to be accounted for in clinical practice and (multi-center) trials investigating thiopurine drugs.


Subject(s)
Mercaptopurine/analogs & derivatives , Specimen Handling/methods , Thioguanine/blood , Chromatography, High Pressure Liquid/methods , Drug Stability , Humans , Inflammatory Bowel Diseases , Mercaptopurine/blood , Mercaptopurine/metabolism , Reproducibility of Results , Statistics, Nonparametric , Thioguanine/metabolism
16.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(30): 3916-9, 2009 Nov 15.
Article in English | MEDLINE | ID: mdl-19828384

ABSTRACT

At our laboratory a reversed phase high performance liquid chromatography assay was developed for analysis of mycophenolic acid in dried blood spot samples. The assay was validated in the range of 0.74-23.4mg/L and proved to be accurate and precise. The developed sample pretreatment procedure was consistent and has a recovery of 95.2% for mycophenolic acid. Hematocrit showed to have influence on the physics of the blood spots and thus on the concentration of mycophenolic acid, therefore standard and control samples should be made with a standardized hematocrit.


Subject(s)
Chromatography, High Pressure Liquid/methods , Chromatography, Reverse-Phase/methods , Mycophenolic Acid/blood , Drug Stability
17.
Ther Drug Monit ; 31(6): 683-7, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19865001

ABSTRACT

A quantitative liquid chromatography (LC)-mass spectrometry (MS)/MS method in human plasma was developed and validated for the tyrosine kinase inhibitors erlotinib, gefitinib, and imatinib in human plasma. Pre-treatment of the samples was achieved by using liquid-liquid extraction using D-8 imatinib as internal standard. Separation was performed on a Waters Alliance 2795 LC system using an XBridge RP18 column. The mass spectrometer Micromass was equipped with an electro spray ionization probe, operating in the positive mode. The calibration curves in plasma were linear for erlotinib, gefitinib, and imatinib over the concentration range of 5 to 3,000; 5 to 3,000, and 5 to 5,000 ng/mL, respectively. The intraday and interday accuracy ranged from 90% to 110% and the intraday and interday precision of the method was within 5%. The reported method provided the necessary linearity, precision, and accuracy to determine tyrosine kinase inhibitors in clinical research and for therapeutic drug monitoring.


Subject(s)
Chromatography, High Pressure Liquid/methods , Piperazines/blood , Pyrimidines/blood , Quinazolines/blood , Tandem Mass Spectrometry/methods , Analytic Sample Preparation Methods , Benzamides , Calibration , Drug Monitoring/methods , Erlotinib Hydrochloride , Gefitinib , Humans , Imatinib Mesylate , Microchemistry , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization/methods
18.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(14-15): 1595-8, 2009 May 15.
Article in English | MEDLINE | ID: mdl-19342319

ABSTRACT

Dried blood spot sampling is a promising and patient friendly alternative for venous sampling. A liquid chromatography tandem mass spectrometer assay was developed for analyzing cyclosporin A in dried blood spots. Linearity ranged from 25 to 1440 microg/L. Within and between run accuracy and precision were within limits. The developed assay has a negligible matrix-effect and a recovery of 97%. The dried blood spots were stable during a period of at least 17 days in the refrigerator. The developed assay is suitable for analyzing cyclosporin A in dried blood spots.


Subject(s)
Chromatography, Liquid/methods , Cyclosporine/blood , Tandem Mass Spectrometry/methods , Humans , Specimen Handling
20.
J Neurol ; 255(6): 903-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18484238

ABSTRACT

OBJECTIVE: We present the electrophysiologic data at baseline of 37 patients who were included in our prospective study on sporadic adult-onset progressive muscular atrophy (PMA). The aim was to correlate electrophysiological signs of lower motor neuron (LMN) loss with clinical signs of LMN loss, and to determine the prognostic value of the distribution of electrophysiological abnormalities in patients who presented clinically with only lower motor neuron signs. METHODS: Thirty-seven patients, who met our inclusion criteria for a prospective study on sporadic adult-onset PMA, underwent extensive standardized electrophysiological examination at baseline, consisting of concentric needle EMG in three regions (cervical, thoracic and lumbosacral) and standardized nerve conduction studies. RESULTS: Denervation on needle EMG was found in 88 % of clinically affected and in 40 % of clinically unaffected limb regions. All patients with a segmental or distal phenotype at baseline who developed generalized weakness had denervation in the thoracic region. Motor nerve conduction abnormalities were found in a substantial number of nerves and included reduced CMAP amplitude, increased distal motor latency, decreased motor conduction velocity, and F-wave abnormalities. Signs of demyelination and sensory nerve conduction abnormalities were rare. CONCLUSIONS: Our electrophysiological data in patients recently diagnosed with sporadic progressive muscular atrophy are consistent with widespread LMN loss. Progression in patients with a segmental or distal onset of PMA may be likely if denervation is found in clinically unaffected regions, including the thoracic region.


Subject(s)
Electrodiagnosis/methods , Motor Neuron Disease/diagnosis , Motor Neuron Disease/physiopathology , Motor Neurons/pathology , Muscular Atrophy, Spinal/diagnosis , Muscular Atrophy, Spinal/physiopathology , Adult , Aged , Amyotrophic Lateral Sclerosis/diagnosis , Amyotrophic Lateral Sclerosis/physiopathology , Disease Progression , Electromyography , Female , Humans , Male , Middle Aged , Muscle Weakness/diagnosis , Muscle Weakness/etiology , Muscle Weakness/physiopathology , Muscle, Skeletal/innervation , Muscle, Skeletal/physiopathology , Nerve Degeneration/diagnosis , Nerve Degeneration/etiology , Nerve Degeneration/physiopathology , Neural Conduction/physiology , Peripheral Nerves/physiopathology , Predictive Value of Tests , Prospective Studies
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