Estudo de custo-efetividade da suplementação de cálcio em baixa dose durante a gravidez para prevenir a pré-eclâmpsia em Manaus

Abstract

Introduction:Pre-eclampsia causes the death of 42 thousand pregnant women annually in the world. The mortality rate is high in developing countries. Of these deaths, 94% would be preventable according to the World Health Organization (WHO), and an alternative to this hypertensive disorder is dietary calcium supplementation for pregnant women. Objective: To verify the cost-effectiveness of administering calcium (500mg/day) in pregnant women to prevent hypertensive disorders and pre-eclampsia from the 16th week of pregnancy onwards in users of the Unified Health System (SUS) in Manaus. Methodology: The economic evaluation study with cost-effectiveness analysis carried out from data of pregnant women recruited in Basic Health Units (UBS) linked to the health system of Manaus, whose maternal and perinatal outcomes were obtained from hospital records of parturients and newborns in maternity hospitals accredited by the SUS. A total of 1020 pregnant women were collected, 510 supplemented with calcium 500 mg/day and 510 without supplementation, with the inclusion criteria being gestational age between 16 and 20 weeks and delivery in public maternity hospitals in Manaus. The perspective of the SUS was adopted, considering the costs practiced in the public system, costs that involve expenses with the acquisition of medicines, supplies and procedures, were calculated in BRL 2022 stock value by the consumer price index (IPCA). A decision tree with alternative and/or decision with supplementation and without supplementation of calcium was elaborated, with the scenarios: with hypertensive disorders, without hypertensive disorders and pre-eclampsia. In the probabilistic sensitivity analysis, the Monte Carlo model was used with 10,000 simulations and threshold analysis to identify the cost of the technology, keeping other parameters unchanged. Regarding static analyses, normality was verified with the Shapiro-Wilk test (P>0.05). Pearson's correlation was observed between total cost and group and maternal diagnosis, the significance was p< 0.05. Result: Supplementary calcium is effective in reducing hypertensive disorders with a lower average cost per patient compared to non-supplemented pregnant women. The average cost of the supplemented group was R$1,729.26 and the non-supplemented group was R$1,800.95. If designed for 100,000 pregnant women, it would generate savings of R$ 7,2 million. The

incremental effectiveness of avoided hypertensive disorders observed between the calcium- supplemented and non-supplemented groups occurred in 99.95% of the 10,000 Monte Carlo

simulations, a positive result that totaled R$ 20.1 million for disorders effect, indicating that calcium supplementation may be a cost-effective alternative. Conclusion: A negative cost (R$ - 86.18) was observed for the consumption of calcium supplementation and a positive effect for the reduction of hypertensive disorders and pre-eclampsia compared to the standard of care without interaction, in comparison to the benefits produced by the calcium consumption to the standard of care that showed a slight increase in effect and cost. a positive result that totaled R$ 20.1 million for disorders, indicating that calcium supplementation can be a cost-effective alternative. Conclusion: A negative cost (R$ -71,69) was observed for the consumption of calcium supplementation and a positive effect for the reduction of hypertensive disorders and pre-eclampsia compared to the standard of care without interaction, in comparison to the benefits produced by the calcium consumption to the standard of care that showed a slight increase in effect and cost. a positive result that totaled R$ 20.1 million for disorders, indicating that calcium supplementation can be a cost-effective alternative. Conclusion: A negative cost (R$ -86.18) was observed for the consumption of calcium supplementation and a positive effect for the reduction of hypertensive disorders and pre-eclampsia compared to the standard of care without interaction, in comparison to the benefits produced by the calcium consumption to the standard of care that showed a slight increase in effect and cost.