Cost-effectiveness analysis of medical management versus conservative surgery for early tubal pregnancy.

STUDY QUESTION: Is conservative surgery (laparoscopic salpingotomy) cost-effective, using fertility as the endpoint compared with medical management (Methotrexate) in women with an early tubal pregnancy? SUMMARY ANSWER: Conservative surgery appeared slightly, but not statistically significantly, more effective than medical management but also more costly. WHAT IS KNOWN ALREADY: Women with an early tubal pregnancy treated with medical therapy (Methotrexate) or conservative surgery (laparoscopic salpingotomy) have comparable future intrauterine pregnancy rates by natural conception. Also, cost-minimisation studies have shown that medical therapy was less expensive than conservative surgery, but there is no cost-effectiveness study comparing these two treatments with fertility as the endpoint. STUDY DESIGN, SIZE, DURATION: A multicentre randomised controlled trial-based (DEMETER study) cost-effectiveness analysis of conservative surgery compared with medical therapy in women with an early tubal pregnancy was performed. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: Included women had an ultrasound that confirmed an early tubal pregnancy. They were randomly allocated to conservative surgery or to medical therapy. The study clinical outcome was the intrauterine pregnancy rate. The payer's perspective was considered. Costs of conservative surgery and medical therapy were compared. The analysis was performed according to the intention-to-treat principle. Missing variables were imputed using the fully conditional method. To characterise uncertainty and to provide a summary of it, a non-parametric bootstrap resampling was executed and cost-effectiveness accessibility curves were constructed. MAIN RESULTS AND THE ROLE OF CHANCE: At baseline, costs per woman in the conservative surgery group and in the medical therapy group were 2627€ and 2463€, respectively, with a statistically significant difference of +164€. Conservative surgery resulted in a marginally, but non-significant (P = 0.46), higher future intrauterine pregnancy rate compared to medical therapy (0.700 vs. 0.649); leading, after bootstrap, to an incremental cost-effectiveness ratio of 1299€ (95% CI = -29 252; +29 919). Acceptability curves showed that conservative surgery could be considered a cost-effective treatment at a threshold of 3201€ for one additional future intrauterine pregnancy. LIMITATIONS, REASONS FOR CAUTION: A limitation was that monetary valuation was carried out using 2016 euros while the DEMETER study took place from 2005 to 2009. Anyway, the results would not have been very different given the marginal changes in the health insurance reimbursement tariffs during this period. WIDER IMPLICATIONS OF THE FINDINGS: Conservative surgery can be considered a cost-effective treatment, if the additional cost of 3201€ per additional future intrauterine pregnancy is an acceptable financial effort for the payer. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: NCT 00137982.

The response of Leuconostoc mesenteroides to low external oxidoreduction potential generated by hydrogen gas.

AIMS: The physiological consequences of low external oxidoreduction potential in Leuconostoc mesenteroides were investigated. METHODS AND RESULTS: Leuconostoc mesenteroides was grown under two initial oxidoreduction potential conditions (Eh7: +200 mV and -400 mV) using nitrogen and hydrogen as reducing agents. Growth was affected by Eh7; the lag phase increased from 1 h at an initial Eh7 of +200 mV to 6 h at an initial Eh7 of -400 mV; the maximum specific growth rate at -400 mV was 68% of the one observed at +200 mV. The NADH/NAD+ ratio and (NADH + NAD+) pool were independent of the external Eh7. CONCLUSIONS: This study shows that changing the external oxidoreduction potential from +200 to -400 mV has a strong effect on the Leuc. mesenteroides physiology. The constancy of the maximum carbon and energetic fluxes (qglu, qATP) under the two Eh7 conditions accompanied by the decrease of YX/S and YATP suggested the existence of an uncoupling phenomenon, namely that some catabolized glucose and hence ATP was not associated with biomass production. SIGNIFICANCE AND IMPACT OF THE STUDY: This paper demonstrates the usefulness of taking into account, the effect of the oxidoreduction potential on the growth of Leuc. mesenteroides in the fermentation process.