Understanding the NSAID related risk of vascular events.
Explore the source record for details and available documents.
Anti-Inflammatory Agents, Non-Steroidal↗
Biomedical subjects
Jacobus R B J Brouwers
Publications and source records attributed to Jacobus R B J Brouwers.
Allele variants of the cytochrome P450 2C9 genotype in white subjects from The Netherlands with serious gastroduodenal ulcers attributable to the use of NSAIDs.
BACKGROUND: The most common serious adverse effects (AEs) associated with NSAID therapy are bleeding and perforated gastroduodenal ulcers. These AEs are dose related, and reduced oral clearance of NSAIDs associated with polymorphisms of cytochrome P450 (CYP) would, theoretically, increase the risk for AEs. OBJECTIVE: The purpose of this study was to determine whether polymorphisms of the CYP2C9 genotype are associated with the development of serious complications of NSAID-related ulcers. METHODS: We examined the records of patients with complications of serious NSAID-related ulcers who were hospitalized from November 2001 to December 2003. Diagnosis was confirmed by endoscopy or abdominal surgery, and a group of consecutive subjects was identified for genetic analysis. CYP2C9 allele frequencies were determined and compared with those in a matched cohort of subjects receiving stable weekly maintenance doses of oral coumarin anticoagulants. Allele frequencies also were compared with those in matched cohorts from earlier studies. RESULTS: All 26 subjects with serious NSAID-related ulcers were white, 15 (58%) were female, and the median age was 74.5 years (range, 32-96 years). All 87 subjects in the reference group were white, 24 (28%) were female, and the median age was 69 years (range, 48-81 years). CYP2C9 genotype frequencies did not differ significantly between subjects with serious complications of NSAID-related ulcers and subjects using oral coumarin anticoagulants. The genotype frequencies in both groups were similar to those reported in previous studies in white subjects. CONCLUSION: The CYP2C9 genotype was not a significant or clinically relevant risk factor in the development of serious NSAID-related ulcers in this group of subjects.
Adult↗
Population pharmacokinetics of oxaliplatin (85 mg/m2) in combination with 5-fluorouracil in patients with advanced colorectal cancer.
Pharmacokinetic (PK) studies of oxaliplatin, using a dose regimen of 85 mg/m, are lacking. A PK model may be used in future studies to investigate the relationship between pharmacokinetics and dose limiting toxicity. The purpose of this study was to construct a population PK model to describe platinum (Pt) concentrations in plasma in 33 patients with colorectal cancer. The secondary objective was to determine the relationship between the amount of Pt in 24-hour urine and the amount of Pt in fractionated urine collection periods. Plasma and urine samples were collected from patients during their first oxaliplatin treatment course. Population PK analysis was performed with WinNonMix. The model that best described the Pt concentrations in plasma was a two-compartment PK model. The elimination clearance (CL) and the elimination clearance of the peripheral compartment (CL2) (median +/- SE) were 25.2 +/- 6.3 L/hr and 68 +/- 24.8 L/hr, respectively. The median volume of distribution (V1) was determined to be 41.6 +/- 9.4 L and the median volume of distribution of the peripheral compartment (V2) was 452.5 +/- 96.4 L. The relationship between the cumulative amount of Pt in urine in the first 12 hours compared with the amount of Pt in 24 hours urine was reflected by a correlation coefficient (r2) of 0.95. The cumulative Pt concentration in urine in the first 10 hours and the first 8 hours compared with 24 hours was reflected by correlation coefficients r2 = 0.93 and r2 = 0.897, respectively. This PK model could be useful in identifying predictors for PK and pharmacodynamic variability to individualize dosing. The results of this study suggest that fractionated urine samples can replace 24-hour urine collection.
Antineoplastic Combined Chemotherapy Protocols↗
Disease-modifying antirheumatic drugs in pregnancy: current status and implications for the future.
Drug use during pregnancy is sometimes unavoidable, especially in chronic inflammatory diseases such as rheumatoid arthritis (RA). The use of disease-modifying antirheumatic drugs (DMARDs) often starts in the early stage of RA; therefore, women of reproductive age are at risk for exposure to a DMARD at time of conception as well as during pregnancy. The aim of this paper was to review recent literature about DMARDs used for rheumatic diseases in pregnancy and to describe the type of study designs and results reported.Twenty-nine studies; eight on hydroxychloroquine/chloroquine, thirteen on methotrexate, three on sulfasalazine and six on azathioprine were identified. With respect to hydroxychloroquine, most studies concluded that it could be safely used in systemic lupus erythematosus or RA. The same conclusions were drawn from the azathioprine studies, but the available evidence is scarce. Although the evidence regarding the safety of methotrexate during pregnancy is conflicting, a high rate of pregnancy losses indicates a risk to the fetus. For each individual case it must be decided whether the benefits outweigh the potential risks. No major teratogenic effects of sulfasalazine were seen although teratogenic effects still can not be excluded. For all other DMARDs, the information on their use in pregnancy was limited. This review underscores the gross absence of data on safety and risks of DMARD use during conception and pregnancy. While young women use these drugs in pregnancy, this review stresses the importance of good monitoring and further research.
Antirheumatic Agents↗
Thalidomide-associated thrombocytopenia.
OBJECTIVE: To report thrombocytopenia in a patient prescribed thalidomide for multiple myeloma (MM). CASE SUMMARY: A 70-year-old woman was diagnosed in 2003 with MM. At diagnosis, melphalan 0.25 mg/kg/day and prednisolone 2 mg/kg/day were started; however, the patient became refractory to therapy. Melphalan and prednisolone were discontinued, and monotherapy with dexamethasone 40 mg for 12 days per month was started. The patient's hematologic condition deteriorated again after about one year; dexamethasone was discontinued, and treatment with oral thalidomide 200 mg/day was initiated. About 2 weeks after thalidomide administration, the woman developed disabling adverse effects (flu-like symptoms, swollen fingers, rash and hematoma on her legs, shortness of breath, dry mouth, multiple petechiae). Laboratory testing showed neutropenia (neutrophils 0.4 x 10(9)/L) and thrombocytopenia (platelets 58 x 10(9)/L). Thalidomide was promptly discontinued; within 3 weeks, the laboratory values returned to pretreatment levels (1.3 x 10(9)/L and 267 x 10(9)/L, respectively) and her symptoms disappeared. DISCUSSION: Thrombocytopenia is a rarely reported hematologic adverse consequence of thalidomide therapy. A recent report identified 5 patients who developed thrombocytopenia while undergoing monotherapy with thalidomide for MM. According to the Naranjo probability scale, thalidomide was classified as the probable cause of thrombocytopenia in our patient. CONCLUSIONS: Unlike other antineoplastic drugs, thalidomide is rarely reported to cause severe hematologic toxicity. We present this case to increase clinicians' awareness for the potential of thalidomide to adversely affect platelet counts, particularly because its effectiveness in MM will likely result in expansion of its clinical use.
Administration, Oral↗
Pharmacogenetics as a tool in the therapy of schizophrenia.
AIM: This review summarises the present knowledge of associations between pharmacogenetics and therapeutic efficacy and side effects of antipsychotics to enable pharmacists to judge the applicability for a more tailor made therapy in patients with schizophrenia. Polymorphisms of Cytochrome P450 isoenzymes and neurotransmitter receptors involved in the efficacy and side effects of antipsychotics are highlighted in this review. METHOD: A search was performed in Medline and EMBASE for the period 1995-August 2002. Also relevant references from the selected papers were incorporated. RESULTS: Poor metabolism with respect to CYP2D6 seems to be related with more pronounced extrapyramidal symptoms and more specifically with a higher incidence of tardive dyskinesia. The C/C-genotype for CYP1A2 results in smokers in a reduction of enzyme activity, but an effect on the incidence of tardive dyskinesia is controversial. For dopamine D2 receptors the effect of the -141C Ins/Del polymorphism on efficacy is not clear yet, although the Taq I polymorphism is associated with greater improvement of positive, but not negative symptoms in acute psychosis. The Gly9-allele of the dopamine D3 receptor is associated with the response to clozapine, but in studies in which the choice of antipsychotics is not restricted, the role of this polymorphism is unclear. The reverse is applicable to the dopamine D(4.2/4.7) polymorphism. For the 5-HT2A receptor the His452Tyr polymorphism is associated with response to clozapine, the 102 T/C polymorphism leads to equivocal results. The polymorphism studied for 5-HT5A, 5-HT6, alpha1A- and alpha2A-receptors give no clear associations with the response to clozapine. The polymorphism studied of the dopamine D2 and D4 receptor are not related to extrapyramidal adverse effects and side effects, respectively. The 9Gly-variant of the dopamine D3 receptor, the 102C-variant, but not the His452Tyr polymorphism of the 5-HT2A-receptor and the 23Ser-variant (for females only) of the 5-HT2C receptor seem to increase the susceptibility to tardive dyskinesia. Weight gain induced by antipsychotics seems to be associated with the -759C-allele of the 5-HT2C receptor. CONCLUSION: The results show the first careful steps toward application of pharmacogenetics in a more individualised, tailor-made, pharmacotherapy. A pre-condition seems to be a multifactorial approach, as can be expected for multifactorial processes.
Antipsychotic Agents↗
Adherence of pharmacoeconomic studies to national guidelines in the Netherlands.
OBJECTIVE: This study examines the adherence of Dutch pharmacoeconomic studies to the national guidelines of conducting a pharmacoeconomic evaluation. METHODS: Dutch guidelines for pharmacoeconomic research were issued in 1999. All Dutch pharmacoeconomic studies that were published in English during 2000-2002 were selected for our review. Two reviewers examined each study for relevance and compared each study with the nine methodological guidelines selected. RESULTS: It was found that 29 studies satisfied the inclusion criteria. The societal perspective was taken in 13 out of the 29 studies (45%), an adequate time period of analysis was chosen in 21 (72%), effectiveness was explicitly differentiated from efficacy in 17 (59%), an incremental analysis was performed in 23 (79%), costs, benefits and health gains were discounted in 24 (83%), effectiveness was expressed in LYGs or QALYs in 16 (55%), reference prices were used in 8 (28%), subgroup analysis was presented in 13 (45%) and sensitivity analysis was included in 26 (90%). CONCLUSIONS: In this review we found that the adherence of studies to some of the Dutch guidelines for pharmacoeconomic studies is fair. However, major improvements are required with respect to the adoption of the societal perspective, presentation of adequate subgroup analyses and application of reference prices.
Clinical Trials as Topic↗
Classification and occurrence of clinically significant drug interactions with irinotecan and oxaliplatin in patients with metastatic colorectal cancer.
BACKGROUND: Pharmacokinetic and pharmacodynamic drug interactions with cytotoxic drugs may significantly influence the efficacy and toxicity of chemotherapy. OBJECTIVE: The purpose of this study was to identify drug interactions with irinotecan and oxaliplatin reported in the literature, to assess their clinical significance, and to examine the occurrence of these interactions in patients with metastatic colorectal cancer treated with either irinotecan or oxaliplatin or both. METHODS: To obtain data on drug-drug interactions with irinotecan and oxaliplatin, a literature search of PubMed and EMBASE was conducted using the search terms irinotecan, oxaliplatin, and interactions (English-language studies only published between 1980 and August 2004). The interactions found were subsequently classified for documentation evidence and severity of clinical effect, according to a 5-level classification system of a standard reference text, by a study panel of medical oncologists and clinical pharmacists. Comedication of patients who were treated with irinotecan or oxaliplatin, or both, was then examined to determine the occurrence of clinically significant interactions. RESULTS: Ninety-eight patients (50 women, 48 men;mean age, 60 years) were included in the study. Seventeen interactions with irinotecan were found in the literature, and 11 were classified as clinically significant. Only 1 nonspecific, clinically significant interaction was identified for oxaliplatin. Irinotecan-treated patients received a mean of 8 different comedications and oxaliplatin-treated patients received a mean of 6. Apart from antiemetic and antidiarrheal drugs that were prescribed for treatment-related toxicities, only 1 patient appeared to be exposed to a possible clinically significant interaction (between irinotecan and phenytoin). CONCLUSIONS: Eleven of the 17 interactions with irinotecan that were found in the literature were classified as clinically significant versus 1 clinically significant interaction with oxaliplatin. The occurrence of these interactions in the study patients with metastatic colorectal cancer was low. For medication surveillance purposes, however, the significant interactions should be considered in clinical practice.
Adolescent↗
Economic evaluation of a randomized trial comparing Helicobacter pylori test-and-treat and prompt endoscopy strategies for managing dyspepsia in a primary-care setting.
BACKGROUND: In western European countries, most dyspeptic patients are initially managed by their general practitioners (GPs), who use a range of strategies to manage dyspepsia. We performed an economic analysis of a Helicobacter pylori test-and-treat strategy versus a prompt endoscopy approach in a primary care setting. METHODS: Data were used from the Strategy: Endoscopy versus Serology (SENSE) study, performed in The Netherlands from 1998 to 2001. Patients were randomized to a prompt endoscopy (n = 105) or test-and-treat (n = 118) group. Follow-up lasted 1 year. Adverse events were not recorded in the SENSE study. Health care costs were based on the total amount of dyspepsia-related drugs used, the number of dyspepsia-related GP visits, the number of diagnostic tests, and the number of dyspepsia-related referrals to specialists. The use of medical resources was calculated as standardized costs for 1999, recorded as euros. (On December 31, 1999, 1.00 Euro = 1.00 US dollar.) Quality of life was measured at inclusion and 1 year later, using the RAND-36 questionnaire. To calculate quality-adjusted life-years (QALYs), we transformed the individual scores of the RAND-36 into 1 overall score, the Health Utilities Index Mark 2, which introduced a limitation to the study. An incremental cost-effectiveness ratio (ICER) was calculated. The 95% confidence limits were calculated using a parametric bootstrap method with angular transformation. All cost data were analyzed from a third-party payer perspective. RESULTS: The total costs per patient were 511 Euros, with 0.037 QALY gained per patient, in the test-and-treat group, and 748 Euros, with 0.032 QALY gained per patient, in the endoscopy group (between groups, P < 0.001 and P = NS, respectively). The point estimate of the ICER indicated that the test-and-treat strategy yielded cost savings and QALYs gained. Parametric bootstrap confidence limits indicated cost savings per QALY gained in 75.7% of the bootstrap simulations. CONCLUSION: This analysis of data from the SENSE1026 study suggests that the H pylori test-and-treat strategy was more cost-effective than prompt endoscopy in the initial management of dyspepsia in general practice, from the perspective of a third-party payer.
Adult↗
Clinical relevance of drug-drug interactions : a structured assessment procedure.
INTRODUCTION: Computerised drug interaction surveillance systems (CIS) may be helpful in detecting clinically significant drug interactions. Experience with CIS reveals that they often yield alerts with questionable clinical significance, fail to provide relevant information on risk factors for the adverse reaction of the interaction and fail to detect all significant drug interactions. These problems highlight the importance of transparency and selectivity in choosing the drug interactions to be included in CIS. In The Netherlands, the Working Group on Pharmacotherapy and Drug Information is responsible for maintenance of the CIS of the Royal Dutch Association for the Advancement of Pharmacy (KNMP). METHODS: The Working Group developed an evidence-based procedure for structured assessment of drug-drug interactions and revised all drug interactions in the CIS accordingly. RESULTS: For every drug interaction four core parameters were assessed: (i) evidence on the interaction; (ii) clinical relevance of the potential adverse reaction resulting from the interaction; (iii) risk factors identifying patient, medication or disease characteristics for which the interaction is of special importance; and (iv) the incidence of the adverse reaction. On the basis of this assessment the drug-drug interactions for inclusion in the CIS were selected. After revision of the drug combinations in the KNMP-CIS, the Working Group judged 22% of the combinations to be not interacting and another 12% to be interacting but not requiring action. On the basis of this assessment the subset of drug combinations for which interaction alerts are generated and the information on management of a drug interaction alert for users of the CIS were adapted. When an alert is generated by the CIS, the user of the system is supplied with comprehensive information on the four core parameters, the mechanism of the interaction and critical information for management of the interaction for the individual patient. DISCUSSION: This structured procedure offers the possibility for transparent and reproducible assessment of the clinical relevance of drug interactions. CONCLUSION: A CIS selectively generating interaction alerts based on this assessment may help in realising the goal of good clinical practice and may offer a methodology to further increase drug safety.
Adverse Drug Reaction Reporting Systems↗
Parenteral gold preparations. Efficacy and safety of therapy after switching from aurothioglucose to aurothiomalate.
OBJECTIVE: For reasons of insufficient quality of the raw material, aurothioglucose was withdrawn from the Dutch market at the end of 2001. Aurothiomalate became available as an alternative preparation. We followed a cohort of patients during the first year after switching from aurothioglucose to aurothiomalate to study efficacy and tolerability. METHODS: Patients were observed at baseline and at 3 and 12 months after switching. At each visit, data on adverse drug reactions (ADR), withdrawal, and disease activity were collected. RESULTS: In total 120 patients were included [age 63(SD 15) yrs, 68% female, 93% with rheumatoid arthritis, duration of disease 15 (SD 9) years, 82% IgM rheumatoid factor-positive, with 9 (SD 9, range 0.1-45) yrs of previous aurothioglucose therapy]. Nineteen patients (16%) reported an ADR taking aurothiomalate not previously experienced with aurothioglucose, the most frequently reported being pruritus, dermatitis/stomatitis, and chrysiasis/hyperpigmentation. Twenty-nine patients (24%) withdrew from aurothiomalate within 12 months of followup for reasons of inefficacy (14%), ADR (7%), or disease in state of remission (3%). Kaplan-Meier estimates show aurothiomalate survival rates of 78.5% after 12 months. No statistically significant differences between the disease activity indicators during followup visits compared with the baseline visit were detected for the patients continuing aurothiomalate. CONCLUSION: Within the first 12 months after switching from aurothioglucose, 24% of patients withdrew from aurothiomalate. Sixteen percent of patients reported novel ADR. For the population continuing to take aurothiomalate no clinically relevant changes in disease activity were recorded after switching.
Adverse Drug Reaction Reporting Systems↗
Cost-benefit analysis of capecitabine versus 5-fluorouracil/leucovorin in the treatment of colorectal cancer in the Netherlands.
BACKGROUND: Capecitabine is an oral prodrug of 5-fluorouracil and has been studied for the treatment of colorectal cancer. In 2 Phase III trials, capecitabine was at least as effective as 5-fluorouracil plus leucovorin and had a more favorable toxicity profile. OBJECTIVE: A cost-benefit analysis was used to assess the pharmacoeconomic profile of capecitabine compared with 5-fluorouracil/leucovorin, given according to the Mayo regimen, for colorectal cancer patients treated in the Netherlands. METHODS: The medical files of patients treated for colorectal cancer at a single center from 1999 to 2002 were examined to determine the numbers of outpatient visits for 5-fluorouracil/leucovorin administration, health care use and medication to manage adverse effects, and travel distance to and from the hospital. The costs of capecitabine treatment were simulated by assuming that the same patients were treated with capecitabine instead of 5-fluorouracil/leucovorin. Toxicity data for capecitabine were derived from 2 Phase III studies that compared capecitabine and 5-fluorouracil/leucovorin. RESULTS: The files of 65 patients were reviewed. Thirty-two patients received adjuvant treatment and 33 patients were treated palliatively for metastatic disease. The mean total costs of palliative treatment were Euro 4004 with capecitabine and Euro 5614 with 5-fluorouracil/leucovorin. These results were robust in sensitivity analyses. The cost savings were primarily related to the number of outpatient visits for capecitabine versus the number of day-care treatment days for 5-fluorouracil/leucovorin, despite the higher acquisition costs of capecitabine. CONCLUSIONS: Based on this analysis, treatment of colorectal cancer with oral capecitabine is cost saving in the Netherlands compared with 5-fluorouracil plus leucovorin administered according to the Mayo regimen. Baseline savings were estimated at Euro 1610 for palliative treatment and Euro 934 for adjuvant treatment.
Administration, Oral↗
Incremental cost-effectiveness of cyclooxygenase 2-selective versus nonselective nonsteroidal anti-inflammatory drugs in a cohort of coumarin users: a pharmacoeconomic analysis linked to a case-control study.
BACKGROUND: A previous case-control study involving concomitant users of coumarin and nonsteroidal anti-inflammatory drugs (NSAIDs) found that cyclooxygenase 2 (COX-2)-selective NSAIDs were associated with fewer bleeding complications than nonselective NSAIDs. OBJECTIVE: The goal of this study was to determine the incremental cost-effectiveness of COX-2-selective versus nonselective NSAIDs in relation to the occurrence of bleeding complications in a cohort of concomitant coumarin users. METHODS: The pharmacoeconomic evaluation was linked to a case-control analysis (patients with and without bleeding complications) based on data from the earlier study in users of concomitant coumarin and NSAIDs. Medical costs associated with NSAID use and bleeding complications were estimated according to Dutch guidelines for pharmacoeconomic analyses, based on Dutch drug prices and national averages for health care costs. Rofecoxib, meloxicam, and nabumetone were considered COX-2 selective. Total costs were calculated and compared for 2 hypothetical scenarios in which patients used either COX-2-selective or nonselective NSAIDs. Sensitivity analyses were performed in which both the odds ratios (ORs) and the costs of NSAIDs and bleeding episodes were varied. RESULTS: A total of 1,491 bleeding complications occurred in 4400 coumarin users: among the 221 (15%) NSAID users with a bleeding episode, 96% used a nonselective NSAID and 4% used a COX-2-selective NSAID. The adjusted OR of a bleeding episode for nonselective compared with COX-2-selective NSAIDs was 3.07 (95% CI, 1.18-8.03). The estimated mean cost of a bleeding episode was 478 per patient. Factoring in the excess cost of a COX-2-selective NSAID compared with a nonselective NSAID, as well as the cost savings in averted bleeding episodes, it was determined that there would be net medical cost savings of 53,800 and 162 averted bleeding episodes if the entire patient group received COX-2-selective NSAIDs rather than nonselective NSAIDs. The sensitivity analysis showed these results to be robust. CONCLUSION: In this study population of concomitant coumarin and NSAID users, the reduction in bleeding complications with the use of more expensive COX-2-selective inhibitors was associated with net medical cost savings compared with nonselective NSAIDs.
Aged↗
Oral antiarrhythmic drugs in converting recent onset atrial fibrillation.
AIM: This article reviews clinical studies on oral antiarrhythmic drugs in converting recent onset atrial fibrillation. An oral loading dose of an antiarrhythmic drug for cardioversion of atrial fibrillation could be an option, due to its simplicity, both for patients admitted to outpatient departments and for episodic treatment by self administration outside the hospital. The latter treatment strategy has recently been pointed out by the American College of Cardiology, the American Heart Association and the European Society of Cardiology as the 'pill in the pocket approach'. METHODS: Articles were identified by Medline 1966 to November 2001 and Embase 1966 to November 2001. Randomized studies of oral antiarrhythmic drugs versus placebo or comparative treatment, which are written in the English language, were selected. Non-randomized or non-comparative studies were selected if the results of an analysis to identify predictors for successful conversion are described. The review of clinical trials is followed by a description of pharmacokinetic parameters of the antiarrhythmic drugs. RESULTS: Studies meeting the inclusion criteria were on propafenone, flecainide, sotalol, amiodarone, quinidine, digoxin and verapamil. Conversion rates of a single oral loading dose of 600 mg propafenone varied between 37% and 41% at 4 h after ingestion. Propafenone was more effective than quinidine, amiodarone and placebo. A single oral dose of 300 mg flecainide restored sinus rhythm in 59% and 68% of patients at 3 h. Flecainide was more effective than amiodarone and placebo. Oral sotalol, digoxin and verapamil were not effective in converting atrial fibrillation to sinus rhythm. CONCLUSION: Propafenone and flecainide are effective in converting recent onset atrial fibrillation. No serious ventricular arrhythmia, other serious proarrhythmic effects or serious non cardiac adverse events were observed. Regular supraventricular tachyarrhythmias with 1:1 AV conduction were rare and were also observed in placebo treated patients. Propafenone and flecainide are more effective in patients with atrial fibrillation of less than 24 h. The association between cardioversion and patient characteristics are not consistent between studies. The pharmacokinetics of flecainide, with lower interindividual variability of absorption kinetics, no genetically determined formation of an active metabolite and a more rapid distribution to myocardial tissue, are more favourable for episodic treatment as compared to propafenone. Both flecainide and propafenone are safe in hospitalized patients. Out of hospital self administration of antiarrhythmic drugs, also described as the 'pill in the pocket approach', could be an option for selected patients, after the treatment has proven to be safe in hospital.
Administration, Oral↗
Pharmacoeconomics of gastrointestinal drug utilisation prior and post Helicobacter pylori eradication.
BACKGROUND: Eradication of Helicobacter pylori prevents recurrence of peptic ulcer. In pharmacoeconomic analyses it is often presumed that after successful eradication no more gastrointestinal drugs are used. We investigated this presumed positive monetary effect using General Practitioners prescribing data, including information in diagnosis. METHODS: From the RNG-database we identified patients with a H. pylori eradication in the years 1997-2000. H. pylori eradication was defined as a prescription of two antibiotics and one gastrointestinal drug on the same day. Patients were divided into a group with diagnosed ulcers and a group without diagnosed ulcers. Gastrointestinal drug costs were calculated for 4 months prior to eradication and 9-12 months post eradication. For comparison costs in all periods were expressed per patient per period. For statistical analysis the paired t-test was used. RESULTS: One hundred and two patients were eligible for evaluation. Of these patients 35 had a diagnosed ulcer and 67 had not. Generally the number of patients on gastrointestinal drugs decreased (61% prior vs. 33% post), however, the drug costs did not change (Euro 33 prior vs. Euro 34 post). Costs for proton pump inhibitors increased post eradication (Euro 14 prior vs. Euro 28 post). The ulcer and nonulcer group showed similar results. CONCLUSION: Helicobacter pylori eradication is thought to be cost effective, however, we did not find a decrease in costs for all gastrointestinal drugs. There may be a great pharmacoeconomical advantage when it is possible to predict which patients are more likely to 'fail' eradication therapy.
Adolescent↗
Potential interaction between acenocoumarol and diclofenac, naproxen and ibuprofen and role of CYP2C9 genotype.
NSAIDs are reported to increase the risk of bleeding in coumarin users. The mechanism underlying this risk is inhibition of platelet aggregation, however a pharmacokinetic mechanism resulting in an increased International Normalised Ratio (INR) was proposed in some case reports in warfarin treated patients. In this retrospective cohort study the influence of diclofenac, naproxen and ibuprofen on the INR of outpatients stabilised on acenocoumarol therapy was investigated. We also determined the role of cytochrome P450 2C9 (CYP2C9) polymorphism on coumarin dosage and INR in NSAID users. The study was carried out at the Groningen Outpatient Thrombosis Service. A retrospective cohort study among patients who received both acenocoumarol and one of the NSAIDs under study was performed. Patients whose INR rose above the upper level of the therapeutic range (INR above 3.5 or 4.0) after an NSAID under study was added to the acenocoumarol therapy, were compared with patients who did not show such an elevation. A two-sample t-test (average acenocoumarol dosage, age), and chi-square tests (sex, therapeutic range, type of NSAID) were used to test for differences. Genotyping was carried out by analysing blood samples for the relevant CYP2C9 alleles. The study population consisted of 112 patients on stable acenocoumarol therapy, of which 52 (46%) showed an elevation of the INR above the desired therapeutic level (INR 3.5 and 4.0 respectively) after the start of an NSAID under study. In 12 patients, the INR increased above 6. The INR of the other 60 patients (54%) remained constant after the start of one of the NSAIDs under study. There were no statistically significant differences between patients with increased INR and patients without increased INR with regard to age, sex, therapeutic range and average acenocoumarol dosage. Eighty patients, of whom 36 showed an increased INR as a result of a potential acenocoumarol-NSAID drug interaction, were included in the genotyping study. No association between CYP2C9 genotype and an increased INR as a result of the drug-drug interaction was found. In nearly half of a cohort of elderly patients, the INR increased beyond the therapeutic range (INR 3.5 or 4.0) as a result of a potential pharmacokinetic drug-drug interaction between acenocoumarol and diclofenac, naproxen and ibuprofen. The average increase in INR was between 1 and 4. Polymorphism of CYP2C9 does not seem to be a relevant risk factor for the NSAID-acenocoumarol interaction.
Acenocoumarol↗
Leflunomide for the treatment of rheumatoid arthritis in clinical practice: incidence and severity of hepatotoxicity.
OBJECTIVE: Leflunomide is a novel disease modifying antirheumatic drug (DMARD). Because of reports on possible hepatotoxicity and adaptations in the recommendations for monitoring liver function during leflunomide treatment, we conducted a study to evaluate the incidence and severity of hepatotoxicity. METHODS: We included consecutive rheumatoid arthritis patients starting treatment with leflunomide in the region of Friesland (The Netherlands) between January 2000 and January 2002. During follow-up patient characteristics, disease characteristics, and clinical and laboratory data on liver functions were registered. Severity of hepatotoxicity was categorised using the National Cancer Institute Common Toxicity Criteria, as moderate (grade 2), severe (grade 3) or life threatening (grade 4). RESULTS: One hundred and one patients were followed for a median period of 10 months (range 0.5-12). Grade 2 or 3 elevations in any liver function blood test were recorded in a total of nine patients (8.9%). No grade 4 elevations were recorded. Four patients (4%) showed grade 2-3 aminotransferase elevations. Due to grade 2 hepatotoxicity one patient (1%) was withdrawn from leflunomide treatment, and one patient continued leflunomide at a reduced dose. In eight of nine patients with grade 2-3 liver function blood tests, these elevated liver function tests occurred within 6 months after starting leflunomide. None of the patients with grade 2 or 3 toxicity had a history of hepatic disease, eight patients concomitantly used potential hepatotoxic co-medication. Eight (8%) patients used leflunomide in combination with methotrexate, and one of these patients developed hepatotoxicity. No clinical signs of serious hepatotoxicity were recorded during follow-up. DISCUSSION: In 8.9% of the patients, grade 2 or 3 hepatotoxicity was recorded within the first year after the start of leflunomide therapy based on liver enzyme determinations. In the majority of the patients liver enzyme elevations occurred within the first 6 months of therapy and resolved during continued follow-up. None of the patients showed clinical signs of hepatotoxicity. CONCLUSION: Under continued monitoring of liver functions hepatotoxicity during leflunomide use does not seem to be a major problem in our population.
Adult↗
A pharmacoeconomic comparison of the efficacy and costs of pantoprazole and omeprazole for the treatment of peptic ulcer or gastroesophageal reflux disease in The Netherlands.
BACKGROUND: The focus of treatment of patients with peptic ulcer or gastroesuphageal reflux disease has changed during the last 15 years, with a shift from histamine2-receptor antagonists to proton-pump inhibitors (PPIs). From 1993 to 2000, expenditures for omeprazole (90% of total market share of PPIs) increased in The Netherlands from 68 million euros to 230 million euros. In 1999, expenditures for pantoprazole accounted for the majority of the rest of the market share for PPIs. OBJECTIVE: The objective of this study was to compare the efficacy and costs of treatment with pantoprazole and omeprazole in The Netherlands. METHODS: First, we reviewed clinical studies that compared the efficacy of different dosages of omeprazole and pantoprazole. Second, we analyzed data from a nationwide database of drug prescriptions to determine the dosages used in daily practice in 1999. The data were based on a representative sample of approximately 40% of the Dutch community pharmacies. Third, we modeled the outcome of potential substitution of pantoprazole for omeprazole and the corresponding scenarios for nationwide cost savings using the prescription information from the nationwide database. Potential savings within the Dutch health care system were estimated. RESULTS: The 1999 prescription data indicated that pantoprazole treatment cost a mean 1.59 euros/d, compared with 2.12 euros/d for omeprazole (1.00 euro = 1.0487 US dollars). The mean cost per defined daily dose of omeprazole was 1.65 euros, compared with 1.59 euros for pantoprazole. Following the summary of product characteristics, treatment with pantoprazole appeared to be less costly for all indications. The projected annual cost savings for substituting pantoprazole for omeprazole on 90% of treatment days were estimated at 40.8 million euros. However, these projected savings may be offset by the costs of switching and the costs of upward dose adjustments that some patients may require. CONCLUSIONS: Based on the available documentation about effectiveness and costs of omeprazole and pantoprazole, pantoprazole may provide a more favorable pharmacoeconomic profile than omeprazole. However, this is only true if the substitution of omeprazole by pantoprazole can be achieved without loss of efficacy or tolerability.
2-Pyridinylmethylsulfinylbenzimidazoles↗