P3815Cost and burden of poor control of the level of anticoagulation in patients with non-valvular atrial fibrillation treated with vitamin K antagonist in the Spanish National Health Service

Introduction

Poorly controlled non-valvular atrial fibrillation (NVAF) patients treated with vitamin K antagonists (VKA) experience higher rates of clinical events compared to well controlled patients. In Spain a high percentage of NVAF patients present an inadequate control of anticoagulation therapy, whose economic impact has not been reported yet.

Purpose

To estimate the impact on resource consumption, clinical events and mortality of poorly controlled NVAF patients≥65 years treated with VKA in Spain.

Methods

A cost-consequence analytic model was developed to estimate differences on clinical events and cost between poorly controlled (TTR<65%) and well controlled (TTR≥65%) NVAF patients treated with VKA over 1 year. A hypothetical cohort of NVAF patients was estimated by using local epidemiological studies. Anticoagulation control rates, as measured by Rosendaal method, were retrieved from a literature review of Spanish real-world studies.

Clinical event rates (ischemic stroke-IS-, hemorrhagic stroke-HS-, major bleeding-MB-, systemic embolism-SE- and death for any cause) were derived from a post-hoc analysis of SPORTIF III/V trials. A sensitivity analysis (SA) was performed by using event rates from a prospective single-center study carried out in Spain.

Societal and National Health Service (NHS) perspectives were considered. Total annual costs (€ 2018) included clinical event direct, non-direct healthcare cost and indirect-costs. Potential life years lost (PLYL) were calculated to report impact on mortality. An expert panel composed by a cardiologist, a haematologist and general practitioners validated the model inputs.

Results

The target population comprised 594,855 NVAF patients treated with VKA (mean age 73.2 years, 49.4% women, 74.1% CHADS≥2). Poorly controlled anticoagulated patients accounted for 48.3% of the cohort. The inadequate control of anticoagulation was associated with a higher incidence of clinical events compared to well controlled patients within a year (additional 2,143 IS, 390 HS, 201 SE, 6,190 MB and 6,856 deaths). From NHS perspective, the incremental total annual costs associated to poorly controlled patients were €46,685,756.60 (€173.96/patient-year). When considering the societal perspective, the incremental total annual costs of inadequate anticoagulation control reached €97,787,872.59 (€367.51/patient-year). Mortality due to poorly anticoagulation control implied 80,830.65 PLYL (0.136 PLYL/patient-year). The SA confirmed the base case results.

Conclusions

In the Spanish NHS, around 50% of NVAF patients ≥65 years treated with VKA present an inadequate control of the anticoagulation therapy (287,089 patients), which is associated with the increase of clinical events, mortality and costs (up to €100 million). The results of this study highlight a call to action to increase the awareness of the consequences of a poor anticoagulation control and emphasize the need for a better clinical of patients receiving anticoagulation.

Acknowledgement/Funding

BMS and PFIZER contributed to finance the no conditioned to the results of this work.

Long-term fiscal implications of funding assisted reproduction: a generational accounting model for Spain

The aim of this study was to assess the lifetime economic benefits of assisted reproduction in Spain by calculating the return on this investment. We developed a generational accounting model that simulates the flow of taxes paid by the individual, minus direct government transfers received over the individual's lifetime. The difference between discounted transfers and taxes minus the cost of either IVF or artificial insemination (AI) equals the net fiscal contribution (NFC) of a child conceived through assisted reproduction. We conducted sensitivity analysis to test the robustness of our results under various macroeconomic scenarios. A child conceived through assisted reproduction would contribute €370,482 in net taxes to the Spanish Treasury and would receive €275,972 in transfers over their lifetime. Taking into account that only 75% of assisted reproduction pregnancies are successful, the NFC was estimated at €66,709 for IVF-conceived children and €67,253 for AI-conceived children. The return on investment for each euro invested was €15.98 for IVF and €18.53 for AI. The long-term NFC of a child conceived through assisted reproduction could range from €466,379 to €-9,529 (IVF) and from €466,923 to €-8,985 (AI). The return on investment would vary between €-2.28 and €111.75 (IVF), and €-2.48 and €128.66 (AI) for each euro invested. The break-even point at which the financial position would begin to favour the Spanish Treasury ranges between 29 and 41 years of age. Investment in assisted reproductive techniques may lead to positive discounted future fiscal revenue, notwithstanding its beneficial psychological effect for infertile couples in Spain.

Willingness to pay and conjoint analysis to determine women's preferences for ovarian stimulating hormones in the treatment of infertility in Spain

BACKGROUND

Despite many advances in assisted reproductive techniques (ART), little is known about preferences for technological developments of women undergoing fertility treatments. The aims of this study were to investigate the preferences of infertile women undergoing ART for controlled ovarian stimulation (COS) treatments; to determine the utility values ascribed to different attributes of COS treatments; and to estimate women's willingness to pay (WTP) for COS.

METHODS

A representative sample of ambulatory patients ready to receive, or receiving, COS therapies for infertility were recruited from seven specialized private centres in six autonomous communities in Spain. Descriptive, inferential and conjoint analyses (CA) were used to elicit preferences and WTP. Attributes and levels of COS treatments were identified by literature review and two focus groups with experts and patients. WTP valuations were derived by a combination of double-bounded (closed-ended) and open questions and contingent ranking methods.

RESULTS

In total, 160 patients [mean (standard deviation; SD) age: 35.8 (4.2) years] were interviewed. Over half of the participants (55.0%) had a high level of education (university degree), most (78.8%) were married and half (50.0%) had an estimated net income of >€1502 per month and had paid a mean (SD) €1194.17 (€778.29) for their most recent hormonal treatment. The most frequent causes of infertility were related to sperm abnormalities (50.3%). In 30.6% of cases, there were two causes of infertility. The maximum WTP for COS treatment was €800 (median) per cycle; 35.5% were willing to pay an additional €101-€300 for a 1-2% effectiveness gain in the treatment. Utility values (CA) showed that effectiveness was the most valued attribute (39.82), followed by costs (18.74), safety (17.75) and information sharing with physicians (14.93).

CONCLUSIONS

WTP for COS therapies exceeds current cost. Additional WTP exists for 1-2% effectiveness improvement. Effectiveness and costs were the most important determinants of preferences, followed by safety and information sharing with physicians.

Synthesis of ecteinascidin ET-743 and phthalascidin Pt-650 from cyanosafracin B

An efficient new process is described for the synthesis of ecteinascidin ET-743 (1) and phthalascidin (2), starting from readily available cyanosafracin B (3).

A comparative study of the structure of the rDNA intergenic spacer of Lens culinaris Medik., and other legume species

As part of a project on lentil molecular genetics, the sequence of the 18S-25S ribosomal RNA gene intergenic spacer (IGS) of Lens culinaris Medik. was determined. DNA was cloned after polymerase chain reaction (PCR) amplification. The spacer of 2939 bp was composed of nonrepetitive sequences and four tandem arrays of repeated sequences, named A to D. C and D arrays were formed by the repetition of very short consensus sequences. Similarity was found between lentil and other legume species, in particular those of the Vicieae tribe. A transcription initiation site, putative sites of termination and processing, and promoter-enhancer sequences were detected by computer-aided searches. These sites resemble motifs conserved in the IGS sequences of other plant species. The conservation of motifs in the otherwise highly variable plant IGS sequences points to the relevance of these motifs as functional sequences.

Patterns of variation in the intergenic spacers of ribosomal DNA in Drosophila melanogaster support a model for genetic exchanges during X-Y pairing

Detailed analysis of variation in intergenic spacer (IGS) and internal transcribed spacer (ITS) regions of rDNA drawn from natural populations of Drosophila melanogaster has revealed contrasting patterns of homogenization although both spacers are located in the same rDNA unit. On the basis of the role of IGS regions in X-Y chromosome pairing, we proposed a mechanism of single-strand exchanges at the IGS regions, which can explain the different evolutionary trajectories followed by the IGS and the ITS regions. Here, we provide data from the chromosomal distribution of selected IGS length variants, as well as the detailed internal structure of a large number of IGS regions obtained from specific X and Y chromosomes. The variability found in the different internal subrepeat regions of IGS regions isolated from X and Y chromosomes supports the proposed mechanism of genetic exchanges and suggests that only the "240" subrepeats are involved. The presence of a putative site for topoisomerase I at the 5' end of the 18S rRNA gene would allow for the exchange between X and Y chromosomes of some 240 subrepeats, the promoter, and the ETS region, leaving the rest of the rDNA unit to evolve along separate chromosomal lineages. The phenomenon of localized units (modules) of homogenization has implications for multigene family evolution in general.

A race-specific insertion of transposable element IS801 in Pseudomonas syringae pv. phaseolicola

The isolation and cloning of a random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) band specific for Pseudomonas syringae pv. phaseolicola race 1 allowed us to design a pair of primers that amplify 1.2-kb race 1-specific and 2.7-kb race 2-specific fragments, providing a rapid method for the identification of races by standard PCR methods. Restriction analysis revealed identical endonuclease sites in both fragments but the race 2 fragment contains a 1.5-kb insertion, identified as transposable element IS801 by sequence comparison. One complete and one partial open reading frame (ORF), each with a high probability of encoding a protein, have been identified in the 1.2-kb fragment common to both race 1 and race 2 sequences. As IS801 disrupts the partial ORF in the race 2 fragment, the complete sequence of this ORF has been obtained as well as its promoter region. The possibility that it may encode an avirulence gene is discussed as well as the role of transposable elements in pathogen evolution.

Multigene family of ribosomal DNA in Drosophila melanogaster reveals contrasting patterns of homogenization for IGS and ITS spacer regions. A possible mechanism to resolve this paradox

The multigene family of rDNA in Drosophila reveals high levels of within-species homogeneity and between-species diversity. This pattern of mutation distribution is known as concerted evolution and is considered to be due to a variety of genomic mechanisms of turnover (e.g., unequal crossing over and gene conversion) that underpin the process of molecular drive. The dynamics of spread of mutant repeats through a gene family, and ultimately through a sexual population, depends on the differences in rates of turnover within and between chromosomes. Our extensive molecular analysis of the intergenic spacer (IGS) and internal transcribed spacer (ITS) spacer regions within repetitive rDNA units, drawn from the same individuals in 10 natural populations of Drosophila melanogaster collected along a latitudinal cline on the east coast of Australia, indicates a relatively fast rate of X-Y and X-X interchromosomal exchanges of IGS length variants in agreement with a multilineage model of homogenization. In contrast, an X chromosome-restricted 24-bp deletion in the ITS spacers is indicative of the absence of X-Y chromosome exchanges for this region that is part of the same repetitive rDNA units. Hence, a single lineage model of homogenization, coupled to drift and/or selection, seems to be responsible for ITS concerted evolution. A single-stranded exchange mechanism is proposed to resolve this paradox, based on the role of the IGS region in meiotic pairing between X and Y chromosomes in D. melanogaster.

The structure of the rDNA intergenic spacer of Avena sativa L.: a comparative study

The sequence of the 18S-25S ribosomal RNA gene intergenic spacer (IGS) of Avena sativa was determined. DNA was cloned after polymerase chain reaction amplification of the IGS. The spacer of 3980 bp is composed of non-repeated sequences and five tandem arrays of repeated sequences, named A to E. Homology between oats IGS and other grass species was found. Tandem arrays D and E seem to be originated by duplication from single-copy sequences in related species. A transcription initiation site and putative sites of termination, processing and methylation were detected by computer-aided search. These sites resemble motifs conserved in the IGS of plant species.