2012

2012, ETS CN, Informes

Expanded newborn screening of congenital errors of metabolism using tandem mass spectrometry

Full title: Cost-effectiveness of the expanded newborn screening of congenital errors of metabolism using tandem mass spectrometry

Authors: Castilla I, Arvelo-Martín A, Valcárcel-Nazco C, Linertová R, Serrano-Aguilar P, Ruiz-Pons M, Posada M, Dulín-Íñiguez E, Espada M, Zubizarreta R.

Contact person: Iván Castilla Rodríguez (ivan.castillarodriguez@sescs.es)

Summary

Introduction

The incorporation of tandem mass spectrometry to neonatal screening for inborn errors of metabolism has opened the door for expanding those screening programs since, potentially, a large number of diseases may be efficiently screened. However, for many of these diseases, the evidence of the benefit of early detection is still scarce or nonexistent.

Objectives

To determine the efficiency of incorporating five new diseases to a screening program that already uses tandem mass spectrometry for the early detection of MCADD and PKU. These new congenital conditions are homocystinuria, LCHADD, maple syrup urine disease, isovaleric acidemia and glutaric aciduria type 1.

Method

We have developed a decision tree model with two main branches. The first branch incorporates a new pathology to the screening program, whereas the second branch assumes that this condition is not being screened. The same model is used sequentially to estimate the efficiency in terms of cost-effectiveness of incorporating new pathologies, each time adding the accumulated cost and effectiveness of previous pathologies. The analysis incorporates the social perspective, presenting the lifetime costs and effects for the newborns studied. The measure of effectiveness is life-years gained, which have been discounted, as the costs, at a rate of 3%. Costs were expressed as 2012 euros. We performed a multivariate and stochastic sensitivity analysis by means of Monte Carlo simulations, allowing us to compute the acceptability curves and the expected value of perfect information.

Results

The implementation of a screening program for PKU and MCADD using tandem mass spectrometry has an incremental cost of € 3.93 [confidence interval 95%: € 3.02, € 4.71] and an incremental effectiveness of 0.00017 life-years gained [0.00011, 0.00026] by newborn, resulting an incremental cost-effectiveness ratio of 22,774.96 €/AVG [11,734.34, 44,517.73]. Incorporating five new pathologies to this screening program involves an incremental cost of € 11.62 [€ 6.04, € 17.23], and an incremental effectiveness of 0.00042 LYG [0.00028, 0.00057], resulting an incremental cost-effectiveness ratio of 27,607.38 €/AVG [10,567.35, 62,628.36].

Conclusions

The expanded newborn screening program to the five selected pathologies is efficient, on average, for a willingness to pay of 30,000 €/LYG. However, the high uncertainty surrounding the results points to the desirability of further research to reduce the variability in the parameter estimates and increase the robustness of the findings.

PDF (in spanish)

2012, ETS CN, Informes

Cost-effectiveness of the newborn screening of sickle cell disease

Full title: Cost-effectiveness of the newborn screening of sickle cell disease

Authors: Castilla I, Valcárcel-Nazco C, Vallejo-Torres L, Cela E, Posada M, Dulín-Íñiguez E, Espada M, Rausell D, Mar J, Arrospide A, Serrano-Aguilar P.

Contact person: Iván Castilla Rodríguez (ivan.castillarodriguez@sescs.es)

Summary

Introduction

Neonatal screening for sickle cell disease allows the introduction of prophylactic treatments to reduce the incidence and the morbi-mortality associated with the most severe complications of this disease. However, being a rare disease, the cost-effectiveness of this secondary prevention strategy should be carefully assessed.

Objectives

To determine the efficiency of incorporating the early detection of sickle cell disease to neonatal screening programs already implemented in Spanish regions.

Method

A discrete event simulation model has been developed that compares two alternatives: implementing newborn screening for sickle cell disease in a given population that already has a neonatal screening program; or continuing with the clinical detection of this pathology. The model follows the newborns for 10 years, reflecting the impact of preventive treatments that can be established through early detection. The perspective of the analysis was that of the National Health System, taking into account the direct healthcare costs, expressed as 2013 euros. The effectiveness of the intervention was measured by using life expectancy and health related quality of life. Both the costs and effectiveness were discounted at 3%. We performed a probabilistic sensitivity analysis using 2nd order Monte Carlo simulations, which allowed the calculation of acceptability curves and the expected value of perfect information.

Results

Given the estimated birth prevalence in Spain (1:5591), there is a difference in effectiveness of 0.00005 LYGs per infant that favors HbS screening if a time horizon of 10 years is considered. By keeping costs per screened newborn at or below 1 €, neonatal screening for HbS saves costs for the same period. Screening is still efficient, for a willingness to pay of € 30,000 / LYG, if costs per screened newborn are below 2.5 €, incurring a global additional cost of 1.27 € per screened newborn, and obtaining an ICER of € 24,495.72 / LYG (€ 25,343.37 / QALY).

Conclusions

Given the estimated birth prevalence of sickle cell disease in Spain, neonatal screening of this disease is cost-effective for a time horizon of 10 years and setting a willingness to pay of € 30,000 / QALY if the cost per screened newborn does not exceed 2.5 €. The uncertainty surrounding this decision is quite high, being the probability of the screening to be cost-effective not higher than 50% in any of the scenarios assessed.

PDF (in spanish)

2012, ETS CN, Informes

Cost-effectiveness of the newborn screening of cystic fibrosis in Spain

Full title: Cost-effectiveness of the newborn screening of cystic fibrosis in Spain

Authors: Valcárcel-Nazco C, Oliva Hernández C, Velasco González V, Cuéllar-Pompa L, Castilla I, Vallejo-Torres L, Serrano-Aguilar P.

Contact person: Cristina Valcárcel Nazco (cristina.valcarcelnazco@sescs.es)

Summary

Introduction

CF is the autosomal recessive genetic lethal disease most common between white people. It affects many vital organs, being lung disease the responsible for most of deaths. Its incidence in Spain is estimated between 1/6.496 and 1/4.500 newborns per year so CF is included among rare disease.

During the last two decades each Spanish autonomous community has decided the inclusion of newborn screening programs, such as CF neonatal screening, requiring neither prior technology assessment reports nor consensus within the NHS.

Objectives

To determine the cost-effectiveness ratio of each of the main strategies for neonatal screening for cystic fibrosis in Spain.

Method

We have performed a full economic evaluation that compares the cost-effectiveness ratio of each of the main CF newborn screening strategies that are currently being carried out in Spain: IRT/IRT, IRT/DNA, IRT/IRT/DNA and IRT/DNA/IRT versus no screening. We have developed a decision tree with five main branches representing each strategy to be evaluated and the option of not screening the disease. The measures of effectiveness used were LYGs and QALYs. Both cost and effects were discounted at a rate of 3%. A WTP of € 30,000/LYG and € 30,000/QALY was considered. Costs were expressed in euros of 2013.

A probabilistic sensitivity analysis was performed by means of Monte Carlo simulations, allowing us to compute the acceptability curves and the expected value of perfect information.

To determine the parameters that caused greater variability in the model results, ANCOVA models were applied to Monte Carlo simulations.

Results

Results of the economic evaluation model show that newborn screening for CF is an efficient alternative. The IRT+IRT+DNA screening strategy has a lower ICER compared with no screening (8,801.46 €/LYG and 4,024.85 €/QALY). The screening strategy with higher ICER is IRT+DNA+IRT (16,394.59 €/LYG y 7,497.14 €/QALY).

Conclusions

CF neonatal screening is an efficient alternative in terms of cost-effectiveness from the perspective of the NHS, resulting in a profit on health outcomes of patients in both LYG and QALY.

PDF (in spanish)