Suplementação de cálcio na prevenção de pré-eclâmpsia: uma revisão sistemática de ensaios clínicos aleatorizados

Abstract

Background: Preeclampsia is a multisystem disease that occurs mainly in the second half of pregnancy, is characterized by hypertension and proteinuria, affecting approximately 10% of pregnancies, being the main cause of maternal and perinatal mortality. Studies show an increase in its incidence in populations with low calcium intake, however, there is little evidence in the scientific literature about the effectiveness of calcium in preventing pre-eclampsia. Objective: efficacy and effectiveness of the effect of calcium supplementation on the manifestation of preeclampsia and perinatal outcomesin pregnant women. Method: Systematic review of randomized clinical trials. Controlled vocabulary from the "National Library of Medicines" was used through "Medical Subject Headings" (MESH). PubMed; Cochrane; LILACS and registries included Clinical Trials, Current Controlled Trials () and World Health Organization nternational Trials Registry. There was no time limit forthe search and it was completed on June 31, 2021. The qualityof evidence was assessed using the GRADE approach. Results: Thirty RCTs were eligible for this review. A total of 9,544 women used only calcium or calcium plus anothertype of supplement. Of these, 6556 participants used only calcium. Nine RCTs were classified as high or moderate quality. The average adherence rate was 78% in the intervention group and 69% in the control group. Fifteen RCTs that used calcium supplementation in pregnant women versus placebo showed statistically significant values in reducing the incidence of PE. Themain findings were: blood pressure levels, incidences of preeclampsia, prematurity, neonatal morbidity and mortality, maternalmorbidity and mortality, neonatal admissionto the intensive care unit, uterine artery Doppler scan, and stillbirth. Conclusion: Calcium appears to be associated with the prevention of PE, regardless of dosages, initiation of treatment and associations tested. Future studies should mainly considerthe sample size calculation based on the risks of developing PE in subgroups ofpatients, and the measurement of therapeutic adherence through validated methods capable of determining behavioral aspects of pregnant women.www.controlled-trials.com/isrctn/) and World Health Organization International Trials Registry. Therewas no time limit for the search and it was completed on June 31, 2021. The quality of evidence was assessed using the GRADE approach. Results: Thirty RCTs were eligiblefor this review. A total of 9,544 women used only calcium or calcium plus another type ofsupplement. Of these, 6556 participants used only calcium. Nine RCTs were classified as high or moderate quality. The average adherence rate was 78% inthe intervention group and 69% in the control group. Fifteen RCTs that used calcium supplementation in pregnant women versus placebo showed statistically significantvalues in reducing the incidence of PE. The main findings were: blood pressure levels, incidences of preeclampsia, prematurity, neonatal morbidity and mortality, maternal morbidity and mortality, neonatal admission to the intensive care unit, uterine artery Doppler scan, and stillbirth. Conclusion: Calcium appears to be associated with the prevention of PE, regardless of dosages, initiation of treatment and associations tested. Future studies should mainly consider the sample size calculation based on the risks of developing PE in subgroups of patients, and the measurementof therapeutic adherence through validated methods capable of etermining behavioral aspects of pregnant women.