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1.
Artigo em Inglês | MEDLINE | ID: mdl-37861203

RESUMO

OBJECTIVES: We aimed to estimate the age-related risk of ALS in first-degree relatives of patients with ALS carrying the C9orf72 repeat expansion. METHODS: We included all patients with ALS carrying a C9orf72 repeat expansion in The Netherlands. Using structured questionnaires, we determined the number of first-degree relatives, their age at death due to ALS or another cause, or age at time of questionnaire. The cumulative incidence of ALS among first-degree relatives was estimated, while accounting for death from other causes. Variability in ALS risk between families was evaluated using a random effects hazards model. We used a second, distinct approach to estimate the risk of ALS and FTD in the general population, using previously published data. RESULTS: In total, 214 of the 2,486 (9.2%) patients with ALS carried the C9orf72 repeat expansion. The mean risk of ALS at age 80 for first-degree relatives carrying the repeat expansion was 24.1%, but ranged between individual families from 16.0 to 60.6%. Using the second approach, we found the risk of ALS and FTD combined was 28.7% (95% CI 17.8%-54.3%) for carriers in the general population. CONCLUSIONS: On average, our estimated risk of ALS in the C9orf72 repeat expansion was lower compared to historical estimates. We showed, however, that the risk of ALS likely varies between families and one overall penetrance estimate may not be sufficient to describe ALS risk. This warrants a tailor-made, patient-specific approach in testing. Further studies are needed to assess the risk of FTD in the C9orf72 repeat expansion.


Assuntos
Esclerose Lateral Amiotrófica , Demência Frontotemporal , Humanos , Idoso de 80 Anos ou mais , Demência Frontotemporal/genética , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Expansão das Repetições de DNA/genética , Proteínas/genética
2.
Hum Reprod ; 32(12): 2506-2514, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121269

RESUMO

STUDY QUESTION: Does a reduced FSH dose in women with a predicted hyper response, apparent from a high antral follicle count (AFC), who are scheduled for IVF/ICSI lead to a different outcome with respect to cumulative live birth rate and safety? SUMMARY ANSWER: Although in women with a predicted hyper response (AFC > 15) undergoing IVF/ICSI a reduced FSH dose (100 IU per day) results in similar cumulative live birth rates and a lower occurrence of any grade of ovarian hyperstimulation syndrome (OHSS) as compared to a standard dose (150 IU/day), a higher first cycle cancellation rate and similar severe OHSS rate were observed. WHAT IS KNOWN ALREADY: Excessive ovarian response to controlled ovarian stimulation (COS) for IVF/ICSI may result in increased rates of cycle cancellation, the occurrence of OHSS and suboptimal live birth rates. In women scheduled for IVF/ICSI, an ovarian reserve test (ORT) can be used to predict response to COS. No consensus has been reached on whether ORT-based FSH dosing improves effectiveness and safety in women with a predicted hyper response. STUDY DESIGN SIZE, DURATION: Between May 2011 and May 2014, we performed an open-label, multicentre RCT in women with regular menstrual cycles and an AFC > 15. Women with polycystic ovary syndrome (Rotterdam criteria) were excluded. The primary outcome was ongoing pregnancy achieved within 18 months after randomization and resulting in a live birth. Secondary outcomes included the occurrence of OHSS and cost-effectiveness. Since this RCT was embedded in a cohort study assessing over 1500 women, we expected to randomize 300 predicted hyper responders. PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with an AFC > 15 were randomized to an FSH dose of 100 IU or 150 IU/day. In both groups, dose adjustment was allowed in subsequent cycles (maximum 25 IU in the reduced and 50 IU in the standard group) based on pre-specified criteria. Both effectiveness and cost-effectiveness were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: We randomized 255 women to a daily FSH dose of 100 IU and 266 women to a daily FSH dose of 150 IU. The cumulative live birth rate was 66.3% (169/255) in the reduced versus 69.5% (185/266) in the standard group (relative risk (RR) 0.95 [95%CI, 0.85-1.07], P = 0.423). The occurrence of any grade of OHSS was lower after a lower FSH dose (5.2% versus 11.8%, RR 0.44 [95%CI, 0.28-0.71], P = 0.001), but the occurrence of severe OHSS did not differ (1.3% versus 1.1%, RR 1.25 [95%CI, 0.38-4.07], P = 0.728). As dose reduction was not less expensive (€4.622 versus €4.714, delta costs/woman €92 [95%CI, -479-325]), there was no dominant strategy in the economic analysis. LIMITATIONS, REASONS FOR CAUTION: Despite our training programme, the AFC might have suffered from inter-observer variation. Although strict cancellation criteria were provided, selective cancelling in the reduced dose group (for poor response in particular) cannot be excluded as observers were not blinded for the FSH dose and small dose adjustments were allowed in subsequent cycles. However, as first cycle live birth rates did not differ from the cumulative results, the open design probably did not mask a potential benefit for the reduced dosing group. As this RCT was embedded in a larger cohort study, the power in this study was unavoidably lower than it should be. Participants had a relatively low BMI from an international perspective, which may limit generalization of the findings. WIDER IMPLICATIONS OF THE FINDINGS: In women with a predicted hyper response scheduled for IVF/ICSI, a reduced FSH dose does not affect live birth rates. A lower FSH dose did reduce the incidence of mild and moderate OHSS, but had no impact on severe OHSS. Future research into ORT-based dosing in women with a predicted hyper response should compare various safety management strategies and should be powered on a clinically relevant safety outcome while assessing non-inferiority towards live birth rates. STUDY FUNDING/COMPETING INTEREST(S): This trial was funded by The Netherlands Organization for Health Research and Development (ZonMW, Project Number 171102020). SCO, TCvT and HLT received an unrestricted research grant from Merck Serono (the Netherlands). CBL receives grants from Merck, Ferring and Guerbet. BWJM is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. FJMB receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV and Merck Serono for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics (Switzerland) and for a research cooperation with Ansh Labs (USA). All other authors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number: NTR2657. TRIAL REGISTRATION DATE: 20 December 2010. DATE OF FIRST PATIENT'S ENROLMENT: 12 May 2011.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/fisiologia , Ovário/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Coeficiente de Natalidade , Criopreservação , Feminino , Fertilização in vitro/economia , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Infertilidade/terapia , Variações Dependentes do Observador , Síndrome de Hiperestimulação Ovariana , Reserva Ovariana/efeitos dos fármacos , Indução da Ovulação/métodos , Segurança do Paciente , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
3.
Hum Reprod ; 32(12): 2496-2505, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121326

RESUMO

STUDY QUESTION: Does an increased FSH dose result in higher cumulative live birth rates in women with a predicted poor ovarian response, apparent from a low antral follicle count (AFC), scheduled for IVF or ICSI? SUMMARY ANSWER: In women with a predicted poor ovarian response (AFC < 11) undergoing IVF/ICSI, an increased FSH dose (225/450 IU/day) does not improve cumulative live birth rates as compared to a standard dose (150 IU/day). WHAT IS KNOWN ALREADY: In women scheduled for IVF/ICSI, an ovarian reserve test (ORT) can predict ovarian response to stimulation. The FSH starting dose is often adjusted based on the ORT from the belief that it will improve live birth rates. However, the existing RCTs on this topic, most of which show no benefit, are underpowered. STUDY DESIGN, SIZE, DURATION: Between May 2011 and May 2014, we performed an open-label multicentre RCT in women with an AFC < 11 (Dutch Trial Register NTR2657). The primary outcome was ongoing pregnancy achieved within 18 months after randomization and resulting in a live birth. We needed 300 women to assess whether an increased dose strategy would increase the cumulative live birth rate from 25 to 40% (two-sided alpha-error 0.05, power 80%). PARTICIPANTS/MATERIALS, SETTING, METHODS: Women with an AFC ≤ 7 were randomized to an FSH dose of 450 IU/day or 150 IU/day, and women with an AFC 8-10 were randomized to 225 IU or 150 IU/day. In the standard group, dose adjustment was allowed in subsequent cycles based on pre-specified criteria. Both effectiveness and cost-effectiveness of the strategies were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 511 women were randomized, 234 with an AFC ≤ 7 and 277 with an AFC 8-10. The cumulative live birth rate for increased versus standard dosing was 42.4% (106/250) versus 44.8% (117/261), respectively [relative risk (RR): 0.95 (95%CI, 0.78-1.15), P = 0.58]. As an increased dose strategy was more expensive [delta costs/woman: €1099 (95%CI, 562-1591)], standard FSH dosing was the dominant strategy in our economic analysis. LIMITATIONS, REASONS FOR CAUTION: Despite our training programme, the AFC might have suffered from inter-observer variation. As this open study permitted small dose adjustments between cycles, potential selective cancelling of cycles in women treated with 150 IU could have influenced the cumulative results. However, since first cycle live birth rates point in the same direction we consider it unlikely that the open design masked a potential benefit for the individualized strategy. WIDER IMPLICATIONS OF THE FINDINGS: Since an increased dose in women scheduled for IVF/ICSI with a predicted poor response (AFC < 11) does not improve live birth rates and is more expensive, we recommend using a standard dose of 150 IU/day in these women. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Netherlands Organisation for Health Research and Development (ZonMW number 171102020). T.C.T., H.L.T. and S.C.O. received an unrestricted personal grant from Merck BV. H.R.V. receives monetary compensation as a member on an external advisory board for Ferring pharmaceutical BV. B.W.J.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. F.J.M.B. receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV (the Netherlands) and Merck Serono (the Netherlands) for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics on automated AMH assay development (Switzerland) and for a research cooperation with Ansh Labs (USA). All other authors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number NTR2657. TRIAL REGISTRATION DATE: 20 December 2010. DATE OF FIRST PATIENT'S ENROLMENT: 12 May 2011.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Folículo Ovariano/fisiologia , Ovário/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Coeficiente de Natalidade , Criopreservação , Feminino , Fertilização in vitro/economia , Hormônio Liberador de Gonadotropina/administração & dosagem , Humanos , Infertilidade/terapia , Reserva Ovariana/efeitos dos fármacos , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
4.
Hum Reprod ; 32(12): 2485-2495, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29121350

RESUMO

STUDY QUESTION: Is there a difference in live birth rate and/or cost-effectiveness between antral follicle count (AFC)-based individualized FSH dosing or standard FSH dosing in women starting IVF or ICSI treatment? SUMMARY ANSWER: In women initiating IVF/ICSI, AFC-based individualized FSH dosing does not improve live birth rates or reduce costs as compared to a standard FSH dose. WHAT IS KNOWN ALREADY: In IVF or ICSI, ovarian reserve testing is often used to adjust the FSH dose in order to normalize ovarian response and optimize live birth rates. However, no robust evidence for the (cost-)effectiveness of this practice exists. STUDY DESIGN, SIZE, DURATION: Between May 2011 and May 2014 we performed a multicentre prospective cohort study with two embedded RCTs in women scheduled for IVF/ICSI. Based on the AFC, women entered into one of the two RCTs (RCT1: AFC < 11; RCT2: AFC > 15) or the cohort (AFC 11-15). The primary outcome was ongoing pregnancy achieved within 18 months after randomization resulting in a live birth (delivery of at least one live foetus after 24 weeks of gestation). Data from the cohort with weight 0.5 were combined with both RCTs in order to conduct a strategy analysis. Potential half-integer numbers were rounded up. Differences in costs and effects between the two treatment strategies were compared by bootstrapping. PARTICIPANTS/MATERIALS, SETTING, METHODS: In both RCTs women were randomized to an individualized (RCT1:450/225 IU, RCT2:100 IU) or standard FSH dose (150 IU). Women in the cohort all received the standard dose (150 IU). Anti-Müllerian hormone (AMH) was measured to assess AMH post-hoc as a biomarker to individualize treatment. For RCT1 dose adjustment was allowed in subsequent cycles based on pre-specified criteria in the standard group only. For RCT2 dose adjustment was allowed in subsequent cycles in both groups. Both effectiveness and cost-effectiveness of the strategies were evaluated from an intention-to-treat perspective. MAIN RESULTS AND THE ROLE OF CHANCE: We included 1515 women, of whom 483 (31.9%) entered the cohort, 511 (33.7%) RCT1 and 521 (34.4%) RCT2. Live births occurred in 420/747 (56.3%) women in the individualized strategy and 447/769 (58.2%) women in the standard strategy (risk difference -0.019 (95% CI, -0.06 to 0.02), P = 0.39; a total of 1516 women due to rounding up the half integer numbers). The individualized strategy was more expensive (delta costs/woman = €275 (95% CI, 40 to 499)). Individualized dosing reduced the occurrence of mild and moderate ovarian hyperstimulation syndrome (OHSS) and subsequently the costs for management of these OHSS categories (costs saved/woman were €35). The analysis based on AMH as a tool for dose individualization suggested comparable results. LIMITATIONS, REASONS FOR CAUTION: Despite a training programme, the AFC might have suffered from inter-observer variation. In addition, although strict cancel criteria were provided, selective cancelling in the individualized dose group (for poor response in particular) cannot be excluded as observers were not blinded for the FSH dose and small dose adjustments were allowed in subsequent cycles. However, as both first cycle live birth rates and cumulative live birth rates show no difference between strategies, the open design probably did not mask a potential benefit for the individualized group. Despite increasing consensus on using GnRH antagonist co-treatment in women predicted for a hyper response in particular, GnRH agonists were used in almost 80% of the women in this study. Hence, in those women, the AFC and bloodsampling for the post-hoc AMH analysis were performed during pituitary suppression. As the correlation between AFC and ovarian response is not compromised during GnRH agonist use, this will probably not have influenced classification of response. WIDER IMPLICATIONS OF THE FINDINGS: Individualized FSH dosing for the IVF/ICSI population as a whole should not be pursued as it does not improve live birth rates and it increases costs. Women scheduled for IVF/ICSI with a regular menstrual cycle are therefore recommended a standard FSH starting dose of 150 IU per day. Still, safety management by individualized dosing in predicted hyper responders is open for further research. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Netherlands Organisation for Health Research and Development (ZonMW number 171102020). AMH measurements were performed free of charge by Roche Diagnostics. TCT, HLT and SCO received an unrestricted personal grant from Merck BV. AH declares that the department of Obstetrics and Gynecology, University Medical Centre Groningen receives an unrestricted research grant from Ferring pharmaceutics BV, The Netherlands. CBL receives grants from Merck, Ferring and Guerbet. BWJM is supported by a NHMRC Practitioner Fellowship (GNT1082548) and reports consultancy for OvsEva, Merck and Guerbet. FJMB receives monetary compensation as a member of the external advisory board for Ferring pharmaceutics BV (the Netherlands) and Merck Serono (the Netherlands) for consultancy work for Gedeon Richter (Belgium) and Roche Diagnostics on automated AMH assay development (Switzerland) and for a research cooperation with Ansh Labs (USA). All other autors have nothing to declare. TRIAL REGISTRATION NUMBER: Registered at the ICMJE-recognized Dutch Trial Registry (www.trialregister.nl). Registration number: NTR2657.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Reserva Ovariana , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Hormônio Antimülleriano/metabolismo , Coeficiente de Natalidade , Análise Custo-Benefício , Feminino , Fertilização in vitro/economia , Custos de Cuidados de Saúde , Humanos , Folículo Ovariano/patologia , Síndrome de Hiperestimulação Ovariana , Ovário/fisiologia , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas/economia , Fatores de Tempo , Resultado do Tratamento
5.
BMC Med Res Methodol ; 16(1): 163, 2016 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-27881078

RESUMO

BACKGROUND: Ten events per variable (EPV) is a widely advocated minimal criterion for sample size considerations in logistic regression analysis. Of three previous simulation studies that examined this minimal EPV criterion only one supports the use of a minimum of 10 EPV. In this paper, we examine the reasons for substantial differences between these extensive simulation studies. METHODS: The current study uses Monte Carlo simulations to evaluate small sample bias, coverage of confidence intervals and mean square error of logit coefficients. Logistic regression models fitted by maximum likelihood and a modified estimation procedure, known as Firth's correction, are compared. RESULTS: The results show that besides EPV, the problems associated with low EPV depend on other factors such as the total sample size. It is also demonstrated that simulation results can be dominated by even a few simulated data sets for which the prediction of the outcome by the covariates is perfect ('separation'). We reveal that different approaches for identifying and handling separation leads to substantially different simulation results. We further show that Firth's correction can be used to improve the accuracy of regression coefficients and alleviate the problems associated with separation. CONCLUSIONS: The current evidence supporting EPV rules for binary logistic regression is weak. Given our findings, there is an urgent need for new research to provide guidance for supporting sample size considerations for binary logistic regression analysis.


Assuntos
Viés , Modelos Logísticos , Método de Monte Carlo , Tamanho da Amostra , Simulação por Computador , Humanos , Reprodutibilidade dos Testes
6.
Med Decis Making ; 35(2): 183-95, 2015 02.
Artigo em Inglês | MEDLINE | ID: mdl-24739535

RESUMO

The intervals between screens for the early detection of diseases such as breast and colon cancer suggested by screening guidelines are typically based on the average population risk of disease. With the emergence of ever more biomarkers for cancer risk prediction and the development of personalized medicine, there is a need for risk-specific screening intervals. The interval between successive screens should be shorter with increasing cancer risk. A risk-dependent optimal interval is ideally derived from a cost-effectiveness analysis using a validated simulation model. However, this is time-consuming and costly. We propose a simplified mathematical approach for the exploratory analysis of the implications of risk level on optimal screening interval. We develop a mathematical model of the optimal screening interval for breast cancer screening. We verified the results by programming the simplified model in the MISCAN-Breast microsimulation model and comparing the results. We validated the results by comparing them with the results of a full, published MISCAN-Breast cost-effectiveness model for a number of different risk levels. The results of both the verification and validation were satisfactory. We conclude that the mathematical approach can indicate the impact of disease risk on the optimal screening interval.


Assuntos
Análise Custo-Benefício , Detecção Precoce de Câncer , Modelos Teóricos , Idoso , Biomarcadores Tumorais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/economia , Simulação por Computador , Detecção Precoce de Câncer/economia , Feminino , Humanos , Incidência , Mamografia/economia , Pessoa de Meia-Idade , Medicina de Precisão , Anos de Vida Ajustados por Qualidade de Vida , Fatores de Risco , Sensibilidade e Especificidade , Suíça , Fatores de Tempo
7.
Fertil Steril ; 100(2): 319-27, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23905708

RESUMO

Alongside the debate around clinical, scientific, and ethical aspects of assisted reproductive technology (ART), there exists a parallel debate around the economics of ART treatment and what is the most appropriate funding framework for providing safe, equitable, and cost-effective treatment. The cost of ART treatment from a patient perspective exhibits striking differences worldwide due to the costliness of underlying health care systems and the level of public and third-party subsidization. These relative cost differences affect not only who can afford to access ART treatment but how ART is practiced in terms of embryo transfer practices; in turn significantly impacting the health outcomes and costs of caring for ART conceived children. Although empirical evidence indicates that ART treatment is "good value money" from a societal and patient perspective, the challenge remains to communicate this to policy makers, primarily because fertility treatments are not easily accommodated by traditional health economic methods. Furthermore, with global demand for ART treatment likely to increase, it is important that future funding decisions are informed by what has been learned about how costs and economic incentives influence equity of access and clinical practice. In this review we provide an international perspective on the costs and consequences of ART and summarize key economic considerations from the perspective of ART patients, providers, and society as a whole in the coming decade.


Assuntos
Efeitos Psicossociais da Doença , Custos de Cuidados de Saúde , Infertilidade/economia , Infertilidade/terapia , Aceitação pelo Paciente de Cuidados de Saúde , Técnicas de Reprodução Assistida/economia , Criança , Análise Custo-Benefício , Países Desenvolvidos/economia , Feminino , Humanos , Recém-Nascido , Gravidez
8.
Circ J ; 77(3): 717-24, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23196719

RESUMO

BACKGROUND: In cardiovascular disease, numerous evidence-based prognostic models have been created, usually based on regression analyses of isolated patient datasets. They tend to focus on one outcome event, based on just one baseline evaluation of the patient, and fail to take the disease process in its dynamic nature into account. We present so-called microsimulation as an attractive alternative for clinical decision-making in individual patients. We aim to further familiarize clinicians with the concept of microsimulation and to inform them about the modeling process. METHODS AND RESULTS: We describe the modeling process, advantages and disadvantages of microsimulation. We illustrate the concept using a hypothetical 60-year-old patient, with several cardiac risk factors, who is hospitalized for myocardial infarction. By using microsimulation, we calculate this patient's probability of death. In our example, this particular patient's estimated life expectancy turns out to be 8.9 years. While calculating this life expectancy, we were able to account for multiple outcome events and changing patient characteristics. CONCLUSIONS: Microsimulation takes into account the dynamic nature of coronary artery disease by estimating most likely outcomes regarding a broad range of clinical events. Moreover, microsimulation can be used to evaluate treatment effects by estimating the event-free life expectancy with and without treatment. Hence, microsimulation has several advantages compared to modeling techniques such as regression.


Assuntos
Simulação por Computador , Doença da Artéria Coronariana/complicações , Tomada de Decisões , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Humanos , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Modelos Estatísticos , Prognóstico , Análise de Regressão , Fatores de Risco , Taxa de Sobrevida
9.
BMC Womens Health ; 12: 29, 2012 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-22989359

RESUMO

BACKGROUND: Costs of in vitro fertilisation (IVF) are high, which is partly due to the use of follicle stimulating hormone (FSH). FSH is usually administered in a standard dose. However, due to differences in ovarian reserve between women, ovarian response also differs with potential negative consequences on pregnancy rates. A Markov decision-analytic model showed that FSH dose individualisation according to ovarian reserve is likely to be cost-effective in women who are eligible for IVF. However, this has never been confirmed in a large randomised controlled trial (RCT). The aim of the present study is to assess whether an individualised FSH dose regime based on an ovarian reserve test (ORT) is more cost-effective than a standard dose regime. METHODS/DESIGN: Multicentre RCT in subfertile women indicated for a first IVF or intracytoplasmic sperm injection cycle, who are aged < 44 years, have a regular menstrual cycle and no major abnormalities at transvaginal sonography. Women with polycystic ovary syndrome, endocrine or metabolic abnormalities and women undergoing IVF with oocyte donation, will not be included. Ovarian reserve will be assessed by measuring the antral follicle count. Women with a predicted poor response or hyperresponse will be randomised for a standard versus an individualised FSH regime (150 IU/day, 225-450 IU/day and 100 IU/day, respectively). Participants will undergo a maximum of three stimulation cycles during maximally 18 months. The primary study outcome is the cumulative ongoing pregnancy rate resulting in live birth achieved within 18 months after randomisation. Secondary outcomes are parameters for ovarian response, multiple pregnancies, number of cycles needed per live birth, total IU of FSH per stimulation cycle, and costs. All data will be analysed according to the intention-to-treat principle. Cost-effectiveness analysis will be performed to assess whether the health and associated economic benefits of individualised treatment of subfertile women outweigh the additional costs of an ORT. DISCUSSION: The results of this study will be integrated into a decision model that compares cost-effectiveness of the three dose-adjustment strategies to a standard dose strategy. The study outcomes will provide scientific foundation for national and international guidelines. TRIAL REGISTRATION: NTR2657.


Assuntos
Fertilização in vitro/métodos , Hormônio Foliculoestimulante/administração & dosagem , Infertilidade Feminina/terapia , Adulto , Protocolos Clínicos , Análise Custo-Benefício , Técnicas de Apoio para a Decisão , Esquema de Medicação , Cálculos da Dosagem de Medicamento , Feminino , Fertilização in vitro/economia , Hormônio Foliculoestimulante/economia , Humanos , Infertilidade Feminina/economia , Análise de Intenção de Tratamento , Modelos Logísticos , Análise Multivariada , Países Baixos , Folículo Ovariano/fisiologia , Gravidez , Taxa de Gravidez , Modelos de Riscos Proporcionais , Resultado do Tratamento
10.
BMC Womens Health ; 12: 22, 2012 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-22873367

RESUMO

BACKGROUND: In in vitro fertilization (IVF) and intracytoplasmatic sperm injection (ICSI) treatment a large drop is present between embryo transfer and occurrence of pregnancy. The implantation rate per embryo transferred is only 30%. Studies have shown that minor intrauterine abnormalities can be found in 11-45% of infertile women with a normal transvaginal sonography or hysterosalpingography. Two randomised controlled trials have indicated that detection and treatment of these abnormalities by office hysteroscopy after two failed IVF cycles leads to a 9-13% increase in pregnancy rate. Therefore, screening of all infertile women for intracavitary pathology prior to the start of IVF/ICSI is increasingly advocated. In absence of a scientific basis for such a policy, this study will assess the effects and costs of screening for and treatment of unsuspected intrauterine abnormalities by routine office hysteroscopy, with or without saline infusion sonography (SIS), prior to a first IVF/ICSI cycle. METHODS/DESIGN: Multicenter randomised controlled trial in asymptomatic subfertile women, indicated for a first IVF/ICSI treatment cycle, with normal findings at transvaginal sonography. Women with recurrent miscarriages, prior hysteroscopy treatment and intermenstrual blood loss will not be included. Participants will be randomised for a routine fertility work-up with additional (SIS and) hysteroscopy with on-the-spot-treatment of predefined intrauterine abnormalities versus the regular fertility work-up without additional diagnostic tests. The primary study outcome is the cumulative ongoing pregnancy rate resulting in live birth achieved within 18 months of IVF/ICSI treatment after randomisation. Secondary study outcome parameters are the cumulative implantation rate; cumulative miscarriage rate; patient preference and patient tolerance of a SIS and hysteroscopy procedure. All data will be analysed according to the intention-to-treat principle, using univariate and multivariate logistic regression and cox regression. Cost-effectiveness analysis will be performed to evaluate the costs of the additional tests as routine procedure. In total 700 patients will be included in this study. DISCUSSION: The results of this study will help to clarify the significance of hysteroscopy prior to IVF treatment. TRIAL REGISTRATION: NCT01242852.


Assuntos
Fertilização in vitro , Histeroscopia , Infertilidade Feminina/terapia , Doenças Uterinas/diagnóstico , Útero/anormalidades , Protocolos Clínicos , Análise Custo-Benefício , Feminino , Humanos , Histeroscopia/economia , Infertilidade Feminina/diagnóstico por imagem , Infertilidade Feminina/economia , Infertilidade Feminina/etiologia , Análise de Intenção de Tratamento , Modelos Logísticos , Análise Multivariada , Países Baixos , Preferência do Paciente , Gravidez , Taxa de Gravidez , Modelos de Riscos Proporcionais , Método Simples-Cego , Injeções de Esperma Intracitoplásmicas , Resultado do Tratamento , Ultrassonografia , Doenças Uterinas/complicações , Doenças Uterinas/diagnóstico por imagem , Doenças Uterinas/economia , Útero/diagnóstico por imagem
11.
Hum Reprod ; 27(2): 444-50, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22114108

RESUMO

BACKGROUND: We recently reported that treatment with intrauterine insemination and controlled ovarian stimulation (IUI-COS) did not increase ongoing pregnancy rates compared with expectant management (EM) in couples with unexplained subfertility and intermediate prognosis of natural conception. Long-term cost-effectiveness of a policy of initial EM is unknown. We investigated whether the recommendation not to treat during the first 6 months is valid, regarding the long-term effectiveness and cumulative costs. METHODS: Couples with unexplained subfertility and intermediate prognosis of natural conception (n=253, at 26 public clinics, the Netherlands) were randomly allocated to 6 months EM or immediate start with IUI-COS. The couples were then treated according to local protocol, usually IUI-COS followed by IVF. We followed couples until 3 years after randomization and registered pregnancies and resources used. Primary outcome was time to ongoing pregnancy. Secondary outcome was treatment costs. Analysis was by intention-to-treat. Economic evaluation was performed from the perspective of the health care institution. RESULTS: Time to ongoing pregnancy did not differ between groups (log-rank test P=0.98). Cumulative ongoing pregnancy rates were 72-73% for EM and IUI-COS groups, respectively [relative risk 0.99 (95% confidence interval (CI) 0.85-1.1)]. Estimated mean costs per couple were € 3424 (95% CI € 880-€ 5968) in the EM group and € 6040 (95% CI € 4055-€ 8125) in the IUI-COS group resulting in an estimated saving of € 2616 per couple (95% CI € 385-€ 4847) in favour of EM. CONCLUSIONS: In couples with unexplained subfertility and an intermediate prognosis of natural conception, initial EM for 6 months results in a considerable cost-saving with no delay in achieving pregnancy or jeopardizing the chance of pregnancy. Further comparisons between aggressive and milder forms of ovarian stimulation should be performed.


Assuntos
Fertilização , Infertilidade/terapia , Inseminação Artificial Homóloga , Indução da Ovulação , Adulto , Redução de Custos/economia , Análise Custo-Benefício , Feminino , Fertilização in vitro/economia , Seguimentos , Custos de Cuidados de Saúde , Humanos , Infertilidade/diagnóstico , Infertilidade/economia , Infertilidade/fisiopatologia , Inseminação Artificial Homóloga/economia , Análise de Intenção de Tratamento , Masculino , Países Baixos/epidemiologia , Indução da Ovulação/economia , Gravidez , Taxa de Gravidez , Prognóstico , Índice de Gravidade de Doença , Fatores de Tempo
12.
Fertil Steril ; 96(4): 889-94, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21868001

RESUMO

OBJECTIVE: To compare the cost effectiveness of ovarian reserve testing in in vitro fertilization (IVF). DESIGN: A Markov decision model based on data from the literature and original patient data. SETTING: Decision analytic framework. PATIENT(S): Computer-simulated cohort of subfertile women aged 20 to 45 years who are eligible for IVF. INTERVENTION(S): [1] No treatment, [2] up to three cycles of IVF limited to women under 41 years and no ovarian reserve testing, [3] up to three cycles of IVF with dose individualization of gonadotropins according to ovarian reserve, and [4] up to three cycles of IVF with ovarian reserve testing and exclusion of expected poor responders after the first cycle, with no treatment scenario as the reference scenario. MAIN OUTCOME MEASURE(S): Cumulative live birth over 1 year, total costs, and incremental cost-effectiveness ratios. RESULT(S): The cumulative live birth was 9.0% in the no treatment scenario, 54.8% for scenario 2, 70.6% for scenario 3 and 51.9% for scenario 4. Absolute costs per woman for these scenarios were €0, €6,917, €6,678, and €5,892 for scenarios 1, 2, 3, and 4, respectively. Incremental cost-effectiveness ratios (ICER) for scenarios 2, 3, and 4 were €15,166, €10,837, and €13,743 per additional live birth. Sensitivity analysis showed the model to be robust over a wide range of values. CONCLUSION(S): Individualization of the follicle-stimulating hormone dose according to ovarian reserve is likely to be cost effective in women who are eligible for IVF, but this effectiveness needs to be confirmed in randomized clinical trials.


Assuntos
Técnicas de Apoio para a Decisão , Fertilização in vitro/economia , Cadeias de Markov , Ovário/fisiologia , Adulto , Estudos de Coortes , Análise Custo-Benefício , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Taxa de Gravidez/tendências , Estudos Prospectivos , Adulto Jovem
13.
BJU Int ; 104(1): 41-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19500328

RESUMO

OBJECTIVE To determine how good microsatellite analysis (MA) markers in voided urine samples should be to make a surveillance procedure cost-effective in which cystoscopy is partly replaced by MA for patients with non-muscle-invasive urothelial carcinoma (NMI-UC). PATIENTS AND METHODS We constructed a semi-Markov model with a time horizon of 2 years, and a man aged 65 years as reference case. Data were used from a randomized trial (including 448 patients with NMI-UC from 10 hospitals), and from other data sources. The costs and effects (probability of being in a specific health state) were compared for two surveillance strategies: (i) cystoscopy of the urinary bladder every 3 months (conventional arm), and (ii) semi-automated MA of voided urine samples to identify loss of heterozygosity every 3 months, with a control cystoscopy at 3, 12 and 24 months (test arm). Various sensitivity analyses were used to determine the sensitivity, specificity, and costs of MA of urine for which the test arm was as cost-effective as the conventional arm. RESULTS The probability of being without recurrence after 2 years of surveillance was similar (86.6% conventional arm vs 86.3% test arm) with currently available MA markers (sensitivity of 58% and specificity of 73%). However, the test arm led to higher costs ($4104 vs $3433 per head). The test arm would be as effective and cost the same as the conventional arm if the sensitivity of the currently available MA markers was increased at > or =61%, had a specificity of 73%, and decreased the costs of the MA test per follow-up sample from $158 to <$70. CONCLUSIONS Over 2 years, surveillance in which cystoscopy is partly replaced by currently available urinary MA to reduce patient burden can only provide a cost-effective alternative to the conventional surveillance if the MA urine test had a slightly higher sensitivity and its costs could be reduced.


Assuntos
Cistoscopia/economia , Repetições de Microssatélites/genética , Recidiva Local de Neoplasia/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Análise Custo-Benefício , Métodos Epidemiológicos , Humanos , Perda de Heterozigosidade/genética , Invasividade Neoplásica , Recidiva Local de Neoplasia/economia , Qualidade de Vida , Neoplasias da Bexiga Urinária/economia
15.
Fertil Steril ; 89(2): 331-41, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17662286

RESUMO

OBJECTIVE: To provide detailed information about costs of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment stages and to estimate the cost per IVF and ICSI treatment cycle and ongoing pregnancy. DESIGN: Descriptive micro-costing study. SETTING: Four Dutch IVF centers. PATIENT(S): Women undergoing their first treatment cycle with IVF or ICSI. INTERVENTION(S): IVF or ICSI. MAIN OUTCOME MEASURE(S): Costs per treatment stage, per cycle started, and for ongoing pregnancy. RESULT(S): Average costs of IVF and ICSI hormonal stimulation were euro 1630 and euro 1585; the costs of oocyte retrieval were euro 500 and euro 725, respectively. The cost of embryo transfer was euro 185. Costs per IVF and ICSI cycle started were euro 2381 and euro 2578, respectively. Costs per ongoing pregnancy were euro 10,482 and euro 10,036, respectively. CONCLUSION(S): Hormonal stimulation covered the main part of the costs per cycle (on average 68% and 61% for IVF and ICSI, respectively) due to the relatively high cost of medication. The costs of medication increased with increasing age of the women, irrespective of the type of treatment (IVF or ICSI). Fertilization costs (IVF laboratory) constituted 12% and 20% of the total costs of IVF and ICSI. The total cost per ICSI cycle was 8.3% higher than IVF.


Assuntos
Custos e Análise de Custo , Fertilização in vitro/economia , Injeções de Esperma Intracitoplásmicas/economia , Técnicas de Laboratório Clínico/economia , Criopreservação/economia , Transferência Embrionária/economia , Feminino , Fertilidade , Humanos , Masculino , Recuperação de Oócitos/economia , Indução da Ovulação/economia , Gravidez , Testes de Gravidez/economia
16.
J Heart Valve Dis ; 15(1): 100-6; discussion 106-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16480020

RESUMO

BACKGROUND AND AIM OF THE STUDY: Concern exists regarding progressive root dilatation after the modified Ross procedure. The present prospective echocardiographic study aimed to provide further insight into neo-aortic regurgitation (nAR) and neoaortic root dimensions over time in adult Rotterdam Ross root patients, and to study potential risk factors for nAR and dilatation. METHODS: All Rotterdam Ross patients aged > or = 16 years at surgery were subjected to a prospective biennial standardized echocardiographic protocol. Analysis over time of nAR according to the jet length and jet diameter method, autograft annulus and sinotubular junction (STJ) diameters was carried out using a multilevel linear model in 90 patients who had two or more echocardiographic measurements (mean 5; range 2-9; total 458) up to 14 years (mean 7 years) after surgery. RESULTS: The mean (+/- SE) initial postoperative jet length nAR was grade 0.9 +/- 0.09, and the annual increase 0.1 +/- 0.02 (p < 0.001). Initial annulus and STJ diameters were 25 +/- 0.5 mm and 36 +/- 0.6 mm, while annual increases were 0.4 +/- 0.07 mm and 0.5 +/- 0.09 mm, respectively (p < 0.001). Patients who eventually underwent an autograft reoperation (n = 10) had significantly greater initial nAR and greater progression of nAR, and a greater initial annulus diameter. The annual annulus and STJ diameter increase was greater in patients who underwent autograft reoperation. Compared to freestanding root replacement, patients with inclusion cylinder aortic root replacement had smaller initial annulus and STJ diameters that did not increase over time. Female gender was associated with a greater initial jet length and jet diameter nAR and a greater increase over time in jet diameter nAR. Preoperative aortic regurgitation or combined aortic stenosis and regurgitation were associated with greater initial annulus and STJ diameters. Neither bicuspid valve disease, patient age, preoperative ascending aorta aneurysm, prior aortic valve surgery nor hypertension had an effect on initial or progression of nAR, annulus, and STJ diameter. CONCLUSION: The annual increase in nAR and root dimensions is small, but persistent, after autograft aortic root replacement in adults, and further reoperations should be anticipated. Use of the inclusion cylinder root replacement technique seems to prevent neo-aortic dilatation.


Assuntos
Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Ecocardiografia , Implante de Prótese de Valva Cardíaca , Adolescente , Adulto , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/cirurgia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reoperação , Projetos de Pesquisa , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento
17.
Hum Reprod ; 20(10): 2830-7, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16006473

RESUMO

BACKGROUND: Conventional treatment in normogonadotrophic anovulatory infertility (WHO 2) consists of clomiphene citrate (CC), followed by exogenous gonadotrophins (FSH) and IVF. Response to these treatments may be predicted on the basis of individual patient characteristics. We aimed to devise a patient-tailored, cost-effective treatment algorithm involving the above-mentioned treatment modalities, based on individual patient characteristics. METHODS: Sixteen prognostic groups are defined, according to the presence or absence of: age >30 years, amenorrhea, elevated androgen levels and obesity. The chances of response with each of the three treatments were calculated using prediction models. Treatment costs were based on the data of 240 patients visiting a specialist academic fertility unit. Outcome was an ongoing pregnancy within 12 months after initiation of treatment. The costs per pregnancy of three different strategies were compared, with a threshold for cost-effectiveness of 10 000. RESULTS: The strategy CC + FSH + IVF compared with FSH + IVF generated more pregnancies against lower costs. Compared with CC + IVF, it also produced more pregnancies, but at higher costs. For <30 years of age with normal androgen levels, costs per pregnancy were less than 10 000. For women >30 years old, costs per pregnancy were 25 000 and over 200 000, when presenting with normal or elevated androgen levels, respectively. CONCLUSIONS: The conventional treatment protocol is efficient for women aged <30 years with normal androgen levels. For women >30 years old with elevated androgen levels, FSH may be skipped.


Assuntos
Anovulação/terapia , Clomifeno/uso terapêutico , Fertilização in vitro/métodos , Hormônio Foliculoestimulante/uso terapêutico , Infertilidade Feminina/terapia , Infertilidade/terapia , Indução da Ovulação/economia , Medicina Reprodutiva/economia , Adulto , Fatores Etários , Algoritmos , Amenorreia/diagnóstico , Androgênios/biossíntese , Estudos de Coortes , Análise Custo-Benefício , Feminino , Humanos , Análise Multivariada , Obesidade/diagnóstico , Gravidez , Resultado da Gravidez , Prognóstico
18.
Hum Reprod ; 20(10): 2672-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15979991

RESUMO

The current approach of the basic fertility work-up has been questioned recently in this journal. Based on new data on human fecundity, the authors advocated starting the fertility work-up after just 6 months of trying to conceive instead of the usual 12 months. In women younger than 39 years and with a regular cycle, there are several arguments why the basic fertility work-up should not be done earlier than after 12 months of child wish. Firstly, 50% of couples who have tried to conceive for 6 months without success will conceive in the next 6 months without any treatment. Secondly, the prevalence of fertility diseases is lower in couples who have been trying to conceive for 6 months as compared with those who have been trying for 12 months. Performance of a fertility work-up at this stage will lead to an increase in false-positive diagnoses compared with performing them at 12 months of subfertility. Thirdly, fertility treatment will have fewer additional effects in couples with good spontaneous conception prospects (6-12 months child wish), compared with subfertile couples who have poor prospects. At present, none of the available fertility treatments have success rates comparable with no intervention in these women, and postponement of treatment in such couples will prevent complications such as ovarian hyperstimulation syndrome and multiple pregnancies. We argue that the fertility work-up should not be offered to couples with a duration of child wish of <12 months, except for women with ovulation disorders and women of 39 years and older.


Assuntos
Infertilidade Feminina/diagnóstico , Infertilidade Feminina/economia , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/economia , Medicina Reprodutiva/métodos , Adulto , Coeficiente de Natalidade , Custos e Análise de Custo , Feminino , Fertilização , Humanos , Masculino , Reprodução , Medicina Reprodutiva/economia , Fatores de Tempo , Resultado do Tratamento
19.
Med Decis Making ; 25(2): 168-77, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15800301

RESUMO

The value of a dichotomous diagnostic test is often described in terms of sensitivity, specificity, and likelihood ratios (LRs). Although it is known that these test characteristics vary between subgroups of patients, they are generally interpreted, on average, without considering information on patient characteristics, such as clinical signs and symptoms, or on previous test results. This article presents a reformulation of the logistic regression model that allows to calculate the LRs of diagnostic test results conditional on these covariates. The proposed method starts with estimating logistic regression models for the prior and posterior odds of disease. The regression model for the prior odds is based on patient characteristics, whereas the regression model for the posterior odds also includes the diagnostic test of interest. Following the Bayes theorem, the authors demontsrate that the regression model for the LR can be derived from taking the differences between the regression coefficients of the 2 models. In a clinical example, they demonstrate that the LRs of positive and negative test results and the sensitivity and specificity of the diagnostic test varied considerably between patients with different risk profiles, even when a constant odds ratio was assumed. The proposed logistic regression approach proves an efficient method to determine the performance of tests at the level of the individual patient risk profile and to examine the effect of patient characteristics on diagnostic test characteristics.


Assuntos
Serviços de Diagnóstico/normas , Indicadores Básicos de Saúde , Funções Verossimilhança , Modelos Logísticos , Valor Preditivo dos Testes , Angiografia , Teorema de Bayes , Tomada de Decisões , Serviços de Diagnóstico/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Obstrução da Artéria Renal/diagnóstico por imagem , Obstrução da Artéria Renal/epidemiologia
20.
Eur J Endocrinol ; 152(4): 611-7, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15817918

RESUMO

OBJECTIVE: To assess whether the addition of metformin to gonadotrophin ovulation induction in insulin-resistant, normogonadotrophic, anovulatory women alters ovarian responsiveness to exogenous FSH. DESIGN: Placebo-controlled double-blind assessment in an academic hospital. RESULTS: After a progestagen withdrawal bleeding, patients were randomised for either metformin (n = 11) or placebo (n = 9) treatment. In cases of absent ovulation, exogenous FSH was subsequently administered to induce ovulation. Only during metformin treatment did body mass index and androgen (androstenedione and testosterone) levels decrease, whereas FSH and LH levels increased significantly. In the metformin group, a single patient ovulated before the initiation of exogenous FSH. Significantly more monofollicular cycles and lower preovulatory oestradiol concentrations were observed in women receiving FSH with metformin compared with FSH alone. CONCLUSIONS: Metformin co-treatment in a group of insulin-resistant, normogonadotrophic, anovulatory patients resulted in normalization of the endocrine profile and facilitated monofollicular development during the FSH induction of ovulation.


Assuntos
Anovulação/tratamento farmacológico , Hormônio Foliculoestimulante/administração & dosagem , Metformina/administração & dosagem , Indução da Ovulação/métodos , Adolescente , Adulto , Gonadotropina Coriônica/administração & dosagem , Método Duplo-Cego , Estradiol/sangue , Feminino , Humanos , Placebos
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