Patients with Down’s syndrome have developmental delay and abnormalities in their biological system. Most of the patients cannot take care of themselves. They must have long term treatment which is quite expensive. Currently there is no curative therapy for Down’s syndrome. Screening and prenatal diagnosis to detect abnormalities of Down’s syndrome can help physicians and mothers to make the final decision in pregnancy termination. This can be done in the first or second trimester of pregnancy. However, there are several types of prenatal screening and diagnosis. Each type is different in terms of sensitivity, selectivity, cost, availability and risk. This study aims to compare the costeffectiveness of possible prenatal screening and diagnosis for Down’s syndrome in pregnant women with the application of a health economic evaluation.
Objective: To compare the cost-benefit analyses of prenatal Down syndrome screening and diagnosis of four scenarios in Thailand.
Methods: Decision-analysis modeling was employed, and four scenarios were compared: 1) do nothing (base case), 2) amniocentesis for pregnant women aged > 35 years, 3) prenatal screening and amniocentesis for pregnant women of all ages whose screening test positive, and 4) prenatal screening for pregnant women aged < 35 years and amniocentesis for pregnant women aged > 35 years. Prenatal screening refers to six screening techniques: 1) first trimester serum screening test, 2) combined test, 3) triple test, 4) quadruple test, 5) serum integrated test, and 6) fully integrated test. The societal and government perspectives were used; therefore, costs included direct medical costs, direct nonmedical costs and indirect costs. The outcomes were assessed in terms of resources saved and willingness-to-pay from averted Down syndrome babies. Oneway and probabilistic sensitivity analyses were applied.
Results: Compared to the base case scenario (do nothing), the 3rd scenario yeilded the best value for money. The benefit-to-cost ratio was 1.03 – 1.24 and 73 - 623 baht saved per pregnant woman. The expected number of live births with Down syndrome decreased by half under this scenario. The findings also showed that all screening techniques appeared good value for money under this hypothetical circumstance.Although the anticipated workload of amniocentesis exceeds Thailand’s current capacity, it is possible increase the capacity in the near future. The 2nd scenario also demonstrated good value for money; however, the expected number of live births with Down syndrome decreased slightly. In addition, the amniocentesis workload is far beyond the existing capacity. The 4th scenario generated more costs than benefits and also caused an immense burden on the current amniocentesis capacity.
Conclusion: Prenatal Down syndrome screening and confirm with amniocentesis for every positive test result was the most appropriate financial and practical option. Every screening technique was worthwhile. However, there were several conditions which should be taken into account when selecting the most suitable screening technique, for example, laboratory capacity, gestation age, budget, and the number of capable health personnel who can perform the particular screening test. Some negative consequences needed to bear in mind, for instance, abortions of normal babies due to false positive and risk of miscarriage from amniocentesis procedure.
